SkeptiVet

How to investigate wildlife (or cryptozoology) sightings.

2011-12-01T15:23:00.001-08:00

In light of the recent Jaguar sighting in southern Arizona, I thought it was interesting to get this email from the Arizona Game and Fish Department on how they investigate reports of rare and/or endangered species. Note that eyewitness sightings need to be corroborated with other forms of evidence for such sightings to be officially confirmed. Good quality photographs or video, or other physical evidence are required to confirm these sightings. It is interesting that animals as small as domestic cats are often mistaken for lager cats, and that reports from the public go up dramatically after a sighting, confirmed or not, is reported in the media.
(Click on the email for a larger view)

New Jaguar sighting in southern Arizona.

2011-11-23T18:26:00.001-08:00

The Arizona Game and Fish Department and The Arizona Daily Star are reporting a new sighting of a Jaguar in Arizona. This is the first sighting since the tragic case of Macho B back in February of 2009. It is good to see that Jaguars are still making their way into Arizona despite all the border issues which are potentially getting in their way.

More genetic information on dog breeds, their relationships and possible effects.

2011-11-13T12:12:00.001-08:00

     A recent genetic study in PLoS Genetics has some interesting implications relating to claims made by some dog breeders and many practitioners of alternative veterinary medicine. As our ability to collect and analyze large amounts of genetic data improves, we can learn a lot about how genetics affect the susceptibility of dogs and humans to various diseases. The genetic history of the domestic dog is at least 15,000years, and possibly as much as 100,000 years. Over most of this time, dogs were used for a variety of work including hunting, herding, guarding, and as pets, but breeding practices were haphazard and mixing between types of dogs and even back to wolves as common.

     Basically all modern breeds have been developed in the last 200 years, with many deliberate (small founding populations) and inadvertent (low numbers of dogs during social and political upheavals such as the two world wars) genetic bottlenecks. The history of the Irish Wolfhound is a good example-claims that the breed as it exists today is the same as hounds used in ancient times are not supported by any solid evidence. While it is certain that large sight hounds existed thousands of years ago in the British Isles, the modern breed is the creation of Victorian fanciers who "recreated" the breed in the mid to late 1800's based on their ideas about how the breed should look and on current Victorian ideas of "improving" animals through selective and "pure" breeding.

   While these genetic studies are still preliminary, they are starting to identify gene sequences which have been strongly selected for in the process of creating these breeds. These sequences often contain mutations with major effects on both the phenotype of the dogs and on their health. The diseases which some breeds are very susceptible to are often similar to diseases which also occur in humans, and knowledge of dog genetics is applicable to human health as well. As the specific portions of the genome which affect disease susceptibility are identified, we will learn more about how to avoid many of these health problems in the future. Unfortunately for many of the alternative medicine crowd, claims that diseases like cancer are product of vague "toxins" and modern industrial society are unsubstantiated by the evidence. While it is true that pets can develop cancer due to exposure to specific, known toxins such as secondhand smoke, these exposures are fairly well known and documented in both animals and humans, and are often related to the owner's lifestyle choices more than any generic effect of modernity. While avoiding known toxins such as tobacco smoke is always a good idea, trying to improve our chances with supplements or "superfoods" generally does not work the way we would wish it did.

     The more we learn about the interaction of our genes with the environment, the more we know that disease is often a result of genetic influences which we can control to some extent in domestic animals.
Claims that cancer and autoimmune diseases are caused by specific diets, vaccines, or undefined toxins remain unsubstantiated, and support for them is getting weaker as we learn more about the genetics of dogs and other species.

Arizona Black Rattlesnake

2011-08-02T20:33:00.000-07:00

This little (approximately 18inches long) rattlesnake was hiding in the raspberry bushes along the top of the Mogollon Rim last weekend. It rattled when we got close to warn us away. This is a subspecies of the Western Rattlesnake (Crotalus viridus subspecies cerberus) They tend to occur at relatively high elevations (this one was at about 7500feet above sea level). Some people think that the black color is an adaptation to high altitude that allows the snake to absorb more heat from the sun, although the leaf/needle litter in their habitat also tends to be quite dark. The dark color may serve as good camouflage as well as helping the snake warm up after cool mountain nights. Most rattlesnakes will assume a defensive position such as this, and usually will not strike unless a person or animal steps on them or persists in approaching within striking distance or tries to handle or contact the snake. This snake rattled a little to warn us and retreated into the raspberry patch. Venomous snakes in the wild should be left alone to fill their place in the ecosystem and to avoid injury. See my previous post for information on first aid and treatment of rattlesnake bites.

Buying influence in the early stages of veterinary careers.

2011-06-16T21:16:00.000-07:00

I found a commentary in the latest issue of JAVMA by a second year veterinary student at Colorado State University who is also a lawyer. The commentary addresses the wide variety of free goods, pet foods, medications and industry sponsored seminars provided to veterinary students. When I attended Colorado State 20 years ago, I remember a handful of pharmacy company sponsored seminars and a few coupons for free dog food over the entire 4 years. The seminars were unusual occurrences and there was usually some post-seminar commentary by faculty discussing where the company line may have diverged from the scientific evidence. It would appear things have changed drastically since then.

Here is Michelle Dally's description of the flow of swag that starts the first day of freshman year;

Every first-year veterinary student at Colorado State
University is assigned a small desk in a dingy warren
in the Anatomy building affectionately known as
“the cubes.” These desks are unremarkable in all ways
but one: when students first arrive, they find their desks
piled high with a variety of freebiespens, notepads,
backpacks, notebooks, highlighters, academic calendars,
pet treats, pet food bowls, reference books, and
more—all emblazoned with pet food, pharmaceutical,
and other corporate brand names from across the veterinary
industry. And that is only the beginning.
As the year unfolds, students discover that they are
entitled to free and sharply discounted dog, cat, and
horse food; free heartworm preventative; a free laboratory
coat; and a free clipboard for use in their gross
anatomy laboratory.

In addition to all of the gifts, students are also invited to "work" as student representatives for many of these companies, often for fairly significant amounts of money;

Soon, first-year veterinary students
are receiving e-mails through the official veterinary college
e-mail distribution list encouraging them to apply
to be corporate student representatives for a variety of
companiespositions that typically involve little more
than distributing additional freebies to their classmates
and organizing one or two free lunchtime lectures. In
return for their efforts, these student representatives are
generally paid between $750 and $2,000 per semester.
Some companies employ as many as two student representatives
in each of the 4 veterinary college classes,
whereas others employ only a single representative for
each class or a single representative for the entire college.
Regardless, the upshot is that there are typically
one or two corporate-sponsored free lunches each week
for veterinary students, and the corporate presence in
the veterinary college is palpable.

In addition to the conscious and unconscious effects these gifts and sponsorships may have on students ideas and practices far beyond veterinary school (which is discussed well in the commentary) it leaves the profession as a whole open to other criticisms. Often one of the first accusations used to defend alternative practices or denigrate any science-based treatment which is produced by a pharmaceutical company is that veterinarians are just shills for "big pharma" or "big pet food". The same companies often sponsor veterinary conferences and seminars for veterinarians as well. The alternative veterinary industry really should not throw this particular stone, as their conferences are sponsored by supplement manufacturers and other companies to a similar extent.

The things that I found particularly disturbing about the commentary were the discussion of how these practices are tacitly and actively supported by the veterinary school with very little time spent educating the students on how they may be influenced by them. This is yet another way that veterinary schools are failing to teach their students critical thinking skills and how to evaluate evidence. This type of corporate influence may be even more insidious than teaching alternative practices which are not evidence based in a credulous manner. Students really should be taught how to critically analyze the claims of all of the players in the veterinary industry, from the pharmaceutical companies to the promoters of supplements and alternative treatments. Increasing the access companies have to students as described in this commentary really does open the door for legitimate criticism, as well as giving charlatans something to point to to distract from their own lack of evidence.

I commend Michelle Dally for her commentary and for drawing attention to this topic.

Citation;

Journal of the American Veterinary Medical Association

June 15, 2011, Vol. 238, No. 12, Pages 1551-1554

doi: 10.2460/javma.238.12.1551

Ethical considerations raised by the provision of freebies to veterinary students

Michelle Dally, JD

College of Veterinary Medicine and Biomedical Sciences. Colorado State University, Fort Collins, CO 80523. (Dally)

Ms. Dally was a second-year veterinary student at the time of submission.

Cancer, Autoimmune disease and MHC diversity-should we blame vague toxins and food or inbreeding and closed registries?

2011-05-29T21:29:00.000-07:00

It is common among proponents of certain types of diets and supplements (raw diets, the "evolution" diet, and many types of herbal supplements) to claim that cancer and autoimmune diseases are caused by unidentified "toxins" in commercial foods, vaccines or simply toxins from the environment. Unfortunately, some breeders and even some veterinarians, particularly the "CAVM" crowd, have bought into these ideas, and sometimes try to require new puppy owners to feed specific foods, delay or avoid vaccinations and sometimes avoid certain types of exercise in an attempt to avoid problems that have a strong genetic basis.

Many ideas about breeding dogs date back to the Victorian era when little to nothing was known about genetics and their relationship to the function of the immune system, and ideas of pure blood and avoiding undesirable mixing of different breeds were considered to be the appropriate way to "improve" dogs and other animals. Unfortunately, these ideas were institutionalized and perpetuated through kennel clubs and many breed clubs in the form of policies that allow and even encourage inbreeding (often called "line breeding") and specifically prohibit out-crosses for any reason. The only way to try to eliminate a problem under this system is to eliminate individuals carrying the undesirable genes, which may remove one problem, but is likely to further constrict the gene pool and cause other problems at the same time. While the "holistic" veterinary medicine crowd tries to blame toxins and vaccines, and the large kennel clubs do their best to ignore the underlying problems with their policies, scientists have been working hard to identify the reasons why some breeds are so much more susceptible to certain types of cancer and autoimmune diseases than other dogs or less inbred dogs are.

The underlying genetics associated with susceptibility to several autoimmune diseases and cancers have been discovered in the last few years. While we have known that certain breeds have much higher incidences of certain diseases than others for years (some diseases are named for the breeds which they occur in most frequently), the complexity of the immune system and the genetics associated with it means that only recently have we started to unravel how this affects the health of our pets. There are two main types of Major Histocompatability Complex (MHC) genes in vertebrates-which are also one of the most polymorphic sets of genes in vertebrates-which are involved with identifying different proteins (antigens) and presenting them to the immune system as "self" or "non-self". This is how the immune system regulates which things to attack and remove (bacteria, cells infected by viruses, cancer cells, etc.) and which things to leave alone (normal cells, harmless proteins from food and the environment). In general, having a larger number of diverse MHC genes means that the immune system is better equipped to identify and distinguish good and bad antigens in the body.

In the last few years, researchers have identified varying MHC diversity in different dog breeds. Although it is probably still quite early to use MHC haplotype testing to test for suceptiblity to most diseases, such testing is starting to become available. Many studies have been done identifying specific problems and relationships of specific MHC haplotypes with specific diseases. Some examples include; Autoimmune Hemolytic anemia, Hypothyroidism, Canine Masticatory Myositis, Toller arthritis (a disease similar to Lupus), Canine chronic superficial keratitis, and Doberman Hepatitis. These are just a few of the heritable autoimmune diseases which occur in dogs, and active research continues. MHC diversity is also important for detecting and eliminating cancers, and a lot of research has been done into transmissible tumors in an attempt to discover a way to fight
Devil facial tumor disease in Tasmanian Devils. This research is helping to show how many types of tumors in addition to transmissible tumors evade the immune system. Some inheritable diseases have unsurprisingly been discovered to be unrelated to the MHC genes as well.

This body of research is providing both a broad knowledge of how limited gene pools increase the risk of autoimmune disease and cancer, and which specific genes affect susceptibility to specific diseases. While this line of research will result in specific tests for many of these diseases, eliminating carriers from the population may further restrict genetic variability and is very likely to cause other problems. It would be a much better idea to try to increase diversity in HLA haplotypes first, before eliminating undesirable genes. In some cases, this may mean outcrosses from other breeds to introduce the desirable genetic diversity. In the rare casees that this has been tried, the kennel clubs and breed organizations have not reacted positively. Another problem is that often kennel clubs and breed organizations fund genetic research on purebred dogs, which may deter criticism from organized veterinary medicine.Even worse, the "holistic" or CAVM crowd enthusiastically promote a wide variety of diets, supplements, and even antivaccine nonsense while ignoring the growing body of evidence of genetic problems in purebred dogs. "Holistic" indeed.

For further discussion of these issues in dogs and other animals, see these thoughtful posts;
Pedigree dogs Exposed-How to breed dogs with stronger immune systems.
Border Wars-Inbred Mistakes.
Desert Wind Hounds-MHC, DLA, WTF?
Retrieverman-Misunderstanding the concept of inbreeding tolerance.

Veterinary Homeopaths don't like criticism.

2011-04-14T09:02:00.000-07:00

Please see this post over at The SkeptVet blog; witin 24 hours it is recieving threatening comments from one of the veterinary homeopath's through the North American Veterinary Conference, who should know better. Please repost if you can.

Evidence for using caution with herbal medications in cats.

2011-04-10T20:37:00.000-07:00

photobucket

Veterinarians have known for a long time that cats do not handle certain drugs as well a dogs and other animals do. Drugs such as aspirin, acetaminophen, and other NSAIDs can be much more toxic to cats than to other animals. If we give them to cats at all, they are given in very low, infrequent doses (aspirin) or not at all (acetaminophen). We have known for a long time that cats have much lower levels of the liver enzymes which humans and other animals use to metabolize these drugs. Cats are considered "hypercarnivores", meaning they are adapted to a diet that is 70% or more animal matter. Since most drugs are quite recent inventions, it is obvious that these enzymes did not evolve in response to the drugs which they metabolize but to something else.

A recent paper on PLoS One has worked out the genetics behind this enzyme difference in cats (and a few other animals). These enzymes (Glucuronyltransferases) have developed over many millions of years to deal with toxins found in plants used for food. In species such as cats that do not eat many plants, there is no selective pressure to maintain this type of enzyme function, and mutations can cause the genes coding for them to become inactive. This is what has happened in cats with these particular enzymes, with the result that certain drugs that are chemically similar to some types of plant toxins are much more toxic to cats than they are to other species. This type of issue with drug metabolism is known as a "species defect". While the specific difference in metabolism being discussed here is one of the best known and documented of these species defects, other less well documented differences occur as well.

This has important implications for not only the use of pharmaceuticals of known and controlled dosages, but even more importantly for the use of herbal medications in different species. The problems with herbal medicines are best described in David Colquhoun's Patients Guide to Magic Medicine as "Herbal medicine: giving patients an unknown dose of an ill-defined drug, of unknown effectiveness and unknown safety." The bit about unknown safety is especially applicable in the case of the types of species defects in metabolism that we are discussing here. While some of them are well known, giving an herbal medication that has many different chemical compounds in it may increase the risk of adverse reactions. In addition, the actual dose of active ingredients in herbal products is often very variable, so a product that seems safe when taken once may be toxic the next time. Just because herbs are natural does not mean they are safe, and animals have evolved a lot of natural variability in sensitivity to plant compounds, as this paper documents.

More evidence that acupuncture does not really work.

2011-03-27T22:00:00.000-07:00

There have been several new developments in the evidence base for the effectiveness of acupuncture recently. The first, and more important is a recent systematic review of the evidence for the effectiveness of acupuncture for pain. The Skept Vet has addressed this review in detail here. In short, the review found that the evidence for pain relief in general was contradictory and weak, with the possibility of rare but serious side effects to consider as well. As The Skept Vet points out this type of mild, patient expectation-related effect (placebo effect) may not exist in our animal patients, and any perceived effect may be due more to owner and clinician expectation and observation bias than to any real effect felt by the patient.

Another human study was published recently on the effects of acupuncture on nausea in humans being treated for cancer. This study is interesting because it is one of the few studies which included not only a standard care control group, but also had a sham acupuncture group in addition to the acupuncture group. The sham group involved both a telescopic sham needle and a sham acupuncture point to help control for both patient perception and any effect possibly related to the specific acupuncture point used. The sample sizes in this study were not huge, but were better than many other acupuncture studies, with 62 (standard treatment), 88 (acupuncture) and 95 (sham acupuncture) patients completing the study. The participants in the study were also interviewed top measure their expectations related to the treatment.

The results of the study showed that both the acupuncture and sham acupuncture groups had lower levels of nausea and vomiting than the standard care group, and that this effect was strongly correlated to patient expectations. While the therapists applying the acupuncture were not blinded, the results between the two groups were not significantly different. This study is better controlled than most acupuncture studies in the past have been despite the lack of double blinding. This reinforces the view that many skeptics have that the apparent effects of acupuncture on subjective symptoms such as the perception of pain and nausea may be due to patient expectation rather than any specific physiological effect of the acupuncture itself. Veterinarians claiming that acupuncture is effective should be very careful-their patients may be experiencing some discomfort or pain related to the acupuncture, without any benefit of expectation of improvement, while the veterinarian and owner may believe they see improvement because of their own expectations and desire to help. While an argument may be made that inducing positive expectations in human patients may be useful for managing problems such as pain and nausea, this should be done without misleading the patient or exposing them to risks of serious side effects. In the case of animal patients, it is probably unrealistic to assume that they have the same type of expectation of benefit, and we should be doubly careful to be sure the treatments we use have good evidence of effectiveness.

Pedigree dogs-many health problems are genetic, despite what some say.

2011-02-14T19:25:00.000-08:00

A short video well worth watching if you are not familiar with the problems associated with breed standards and the inbreeding allowed and even encouraged by the large kennel clubs. Unfortunately, many breeders do not understand these problems well enough either and often blame (often with the encouragement of holistic vets) vaccines, ill defined "toxins", commercial dog food, and sometimes the owners for problems that quite clearly have strong genetic components, even when not entirely genetic diseases. These problems have not really received enough attention from organized and science and evidence-based veterinarians, but the alternative and integrative veterinarians seem to be exploiting them without any mention of the responsibility the kennel clubs and breeders hold for creating so many health problems in the first place.

Nonsense On Stilts by Massimo Pigliucci

2011-02-13T21:23:00.000-08:00

Nonsense on Stilts, Massimos Pigliucci's most recent book is and interesting read for anyone interested in distinguishing science from pseudoscience, or from "bunk". The author also discusses the book on the Rationally Speaking podcast, produced by the New York City Skeptics.

While the book does not directly address CAM, it is an interesting and detailed look at the development of science from an historical and philosophical viewpoint that provides a lot of insight into what makes a subject or field scientific, proto-scientific, or just plain nonsense. It includes interesting discussions of what the differences and similarities are between different fields of science (physics and biology, for example) and how something like SETI may not be currently considered science due to it's lack of evidence, but could become scientific if such evidence is found. Some types of alternative medicine clearly fit into the bunk category (homeopathy, reflexology, Reiki, traditional chinese acupuncture) due to the lack of evidence for effectiveness and the complete lack of plausible mechanisms for action. Other things such as herbal medicine can be scientific or not depending on how they are approached by the people pursuing them.

The book is well worth reading for anyone interested in a deeper understanding of how science can be understood as a process practiced by humans, and how it has developed over time. It will give you a better understanding of what science is and how to evaluate claims about different topics.

Dr. Palmquist continues to abuse science on HuffPo.

2010-12-30T20:44:00.000-08:00

I wrote last summer about Dr. Richard Palmquist's first post on Huffington Post, and how his idea of science does not match science as most people understand it. He continues to rely heavily on emotional anecdotes, confuses correlation with causation, and lists a lot of scientific sounding references which usually are of poor quality or do not support his conclusions. In his most recent post, he continues the pattern he established with his first post, but this time promoting the homotoxicolgy ideas he is fond of as scientific advances.

He begins his post with a description of an old cocker spaniel with multiple benign skin tumors that is about to have surgery to remove the masses. As in his other posts, Dr. Palmquist presents these anecdotes in such a dramatic and emotional fashion that it is difficult to tell if he is describing the case accurately, exaggerating, or just making up a good story. That said, I don't know that I have seen a 13 year old cocker spaniel that did not have multiple sebaceous adenomas. Sebaceous adenomas, cysts and other benign masses on or just under the skin are very common in older dogs, and are even more prevalent in certain breeds such as cocker spaniels. I am not sure why anyone thought it was necessary to remove all of the adenomas-as small benign tumors it is fairly common to leave them alone and simply monitor them for problems like inflammation, infection or bleeding. If benign masses like sebaceous adenomas are stable and not causing any problems, most veterinarians will not insist on removing them surgically, and sometimes they will resolve on their own. Often they will bother the animal's owner more than the animal, which is one reason to remove them, and since they are usually fairly small, superficial skin tumors, they can often be removed fairly easily using a reversible sedative, local anesthetics, and a few days of fairly safe pain relievers, so Dr. Plamquist's representation of the surgery as quite painful, seems like an exaggeration, as well as the impression that not doing the surgery is some kind of revolutionary idea on his part. Where He really goes off the rails however, is in his representation to the owner that the adenomas, which very likely have a genetic component to their development because of their high incidence in certain breeds, are caused by ill-defined "toxins" and should be treated with a variety of homeopathic preparations. If the adenomas really resolved on their own as Dr. Palmquist describes, it is more likely to be a result of inflammation related to the previous biopsies (described as "special testing" in the post) or simply a coincidence than due to the homeopathic remedies he provided. Some of the remedies made by Heel are low dilutions, so there is the possibility that there was some active ingredient in the treatment, but the dose was still likely to be very small. Amusingly, the one mass that did not resolve on it's own is explained away as being on an acupuncture point. Somehow the point or the tumor magically "knows" something and is trying to tell us the dog needs it there to maintain circulation to the brain and cognitive ability. There are some Chinese studies that claim to demonstrate this type of benefit, but unfortunately nearly all studies of acupuncture from china are positive, suggesting publication and other biases, which make it difficult to evaluate such studies. There has not been any research replicating these findings elsewhere. Because of this magical location on an acupuncture point, they decided to watch the tumor, which has been stable for years. As I said before, many veterinarians will do the same thing with no need to come up with magical rationalizations for it.

These ideas come from a early to mid 20th century offshoot of homeopathy called "homotoxicolgy". Hans-Heinrich Reckeweg, the inventor of homotoxiclogy, denied the germ theory of infectious disease and included vaccines and pharmaceutical treatments in the "toxins" which he thought needed to be removed from the body. Heel, the company founded by Reckeweg, has been in trouble in the past for fraudulent claims and marketing of it's products, and a review of randomized trials of Heel products by Edzard Ernst and K. Schmidt revealed serious flaws in the studies and a lack of evidence supporting their use. For a self-proclaimed "research geek", the references Dr. Palmquist supplies to support his views seem to be accepted credulously and uncritically, and perhaps with the expectation that nobody will actually check to see what the references actually say. Most of the studies are in-vitro, preliminary and published in questionable journals such as Medical Hypotheses or alternative medicine journals which are often uncritical of poor studies and biased toward promoting their particular modality. One of the references has been thoroughly discussed by Dr. Rachie and Orac, (shockingly, the 87% alcohol used as diluent for the remedies is toxic to cancer cells in vitro!) the Cochrane review provides very weak support despite being authored by homeopaths. the authors concluded;

"This review found preliminary data in support of the efficacy of topical calendula for prophylaxis of acute dermatitis during radiotherapyand Traumeel S mouthwash in the treatment of chemotherapy-induced stomatitis. These trials need replicating. There is no convincingevidence for the efficacy of homeopathic medicines for other adverse effects of cancer treatments. Further research is required."

The one study of companion animals published in a more mainstream journal (Neumann S, Stolt P, Braun G, Hellmann K, Reinhart E. 2010. Effectiveness of the Homeopathic Preparation Zeel Compared with Carprofen in Dogs with Osteoarthritis. J Am Anim Hosp Assoc. Dec 16. [Epub ahead of print]) was uncontrolled, unblinded, and has other problems, including an average age difference of nearly 3 years between the two treatment groups, with the younger group recieving the homeopathic remedy. This study was also funded by Heel, the producer of the homeopathic remedy.

Finally, Dr. Palmquist describes how he thinks medicine should "work", by which he means new therapies should be developed. Unfortunately, the order of investigation he describes is somewhat backward. Plausibility should be the first test for any treatment, and his statement that homeopathic remedies have been proven to work and have understandable mechanisms flies in the face of our understanding of basic physics and chemistry, and is only accepted by true believers in homeopathy. Anecdotal evidence for effectiveness is not a reliable way to discover new treatments and is only a very preliminary way to start to investigate a new treatment. Exceedingly implausible treatments like homeopathy are probably not worth studying further, as preliminary weakly positive results are likely to be the result of bias, coincidence and random chance. These type of preliminary positive results seem to always disappear in better designed trials of homeopathy. While I am sure Dr. Palmquist means well, he is a poster child for demonstrating how cognitive errors and wishful thinking can lead us down a path full of dead ends and useless therapies. Unfortunately, his influence as president of the AHVMA and a member of AAHA gives him an undeserved platform to promote his delusions. In this case, no harm was done to the patient, but sometimes the result is not so good.

Life and Death in the winter snow.

2010-12-30T16:09:00.000-08:00

I noticed feathers falling past my front window this afternoon and looked outside to find this Sharp-Shinned Hawk eating a small bird in the Ponderosa Pine tree in the front yard. The temperature outside was 13 degrees Fahrenheit. A small bird needs to consume a lot of calories to survive in these temperatures.

Twisting facts to suit "theory". How smart people can fool themselves.

2010-12-08T19:54:00.000-08:00

“It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories instead of theories to suit facts.”
Sir Arthur Conan Doyle

It often seems strange how frequently smart, well educated people seem to fall for pseudoscience. Doctors and Veterinarians are certainly no exception, and it is not unusual to see veterinarians recommending poorly evidenced treatments or even treatments with evidence against their effectiveness. People often ask how a trained medical professional can fall for such things and then promote them. In addition to regression to the mean, selection bias and other cognitive errors, we are all prone to the illusion of control. A recent paper in the British Journal of Psychology (discussion by Ben Goldacre here as the entire paper is behind a paywall) helps to demonstrate how this illusion can develop in medical professionals and suggests some ways to avoid it. Unfortunately, many veterinary school curricula and continuing education rely heavily on a fairly authoritarian presentation of information and rote memorization that do not help students to learn to evaluate claims critically and understand the evidence base behind various treatments.

In recent comments on The SkeptVet Blog, several different people have suggested that skeptics should not criticize alternative treatments until they have tried them.This advice is given without an awareness of how easily we all make cognitive errors and how those errors can give us an illusory view of the effectiveness of our treatments. To be fair, we are all just as susceptible to this type of cognitive error no matter what type of treatment we are using, and we should always be wary of misdiagnosis or inappropriate treatment selection, situations in which these types of cognitive errors are common in both evidence based and alternative medical treatments. It underlines the importance of blinded, controlled trials, and the evaluation of the strength of the evidence supporting any treatment in as objective a way as possible. "Trying it for yourself" is just a good way to fool yourself, and the more confident you are in your experience and ability, the more likely you are to believe that an ineffective treatment works. This new psychological paper just demonstrates the idea again in a relevant way.

Bad Science

2010-10-21T22:33:00.000-07:00

An excellent read, with well written descriptions of how ineffective treatments can seem to work, and how smart people can believe that they do. Recently released in the US, so pick one up if you are interested.

Discovering a new species; what kind of evidence is good enough?

2010-10-14T19:06:00.000-07:00

Well, the actual animal in hand is usually sufficient. Scientists are still discovering new species (unknown to science, if not to the local residents) on a regular basis. For some reason, it is biologists making these finds, not cryptozoologists, who seem to spend more time either chasing after or perpetrating hoaxes rather than finding real evidence for unknown animals. While a large primate living in North America would be an amazing discovery, the fact that no one has found any definitive evidence in the form of a body, bones, DNA, or even fossil evidence would seem to indicate that the probability of it's existence is close to zero. The real animals still being discovered are fascinating enough.

Photo credit; Durrell Wildlife Conservation Trust

An Anti-vaccine Veterinarian-an interesting mix of pseudoscience, faith, and nonsense.

2010-09-25T21:44:00.000-07:00

A particularly egregious example of an anti-vaccine veterinarian was brought to my attention recently (hat tip to Terrierman). Dr.Patricia Jordan has published online a poster she presented at the 5th annual joint North American Homeopathic Conference this year. Her personal website (titled "Mark of The Beast-hidden in plain sight-the case against vaccinations" by which she appears to mean that vaccinations are the mark of the beast) also reveals similar ideas which add up to an interesting mix of misinterpreted and misrepresented science, what appears to be the influence of evangelical style christian creationism, big-pharma and government conspiracy theories, and just plain making things up to suit her ideology. This type of ridiculous reasoning is one of the things that makes me very skeptical of information coming from alternative medicine professional organizations such as the American Holistic Veterinary Medical Association or Homeopathic associations-all to often they seem to accept ideas such as Dr. Jordan's uncritically.

From the Curriculum Vitae page on her website, it would appear that Dr. Jordan had a distinguished undergraduate and veterinary school career in the 1980's with several externships and even some type of award for epidemiology. Since the late 1990's it would seem that she has not found a variety of alternative medicine she does not like, including Reiki, homeopathy, acupuncture, traditional Chinese medicine, spinal manipulation and "pulse diagnosis". The legitimate scientific veterinary conferences and seminars she has attended in that time appear to consist mostly of vaccine related events, which she has apparently interpreted as evidence that vaccines are the cause of nearly all disease and some kind of spiritual menace. She conveniently ignores the fact that many vaccine preventable diseases in animals and humans have huge costs in mortality and morbidity by orders of magnitude over any evidence for adverse effects of vaccinations. It makes me wonder if she has ever seen a case of canine distemper, parvovirus or Rabies, or any of the other viruses we routinely prevent with vaccination.

To be fair, there has been a legitimate scientific debate over vaccination of pets over the last 10-20 years which has resulted in some significant changes in vaccination protocols for pets. All Rabies vaccines were changed to killed virus vaccines in the 1980's when it was found that the modified live virus vaccines could, in rare cases, cause rabies. In cats, this had the unintended result of causing malignant tumors in some cats (1). This can also happen in dogs, but is much more rare than it's incidence in cats, which has been reported between one in 1,000 to one in 10,000 cats. Other adverse effects of vaccination are primarily acute and delayed allergic reactions, with very little evidence that other diseases, such as autoimmune disease, other types of cancer, neurological or behavioral diseases are caused by vaccination. For a detailed analysis of these issues, visit The SkeptVet here. While vaccinations can trigger allergic reactions and on rare occasions various autoimmune diseases, this is not proof that the vaccination causes these problems. The greatly varying incidence of allergies and autoimmune disease among different breeds would suggest underlying genetic susceptibilities, and any naturally acquired infection or allergen exposure is as likely or more likely to trigger an outbreak as a vaccination is. As evidence has accumulated about the duration of immunity from vaccination, most veterinarians have switched from annual vaccination protocols to 3-4 year protocols for most vaccines, and I would not be surprised if some of these were extended even more as more evidence is accumulated for longer duration of immunity. Despite this active scientific evaluation of animal vaccination over the past decade or so, Dr. Jordan seems to have decided for ideological reasons that all vaccinations are bad. Lets look at some of the claims she makes and compare them with the science.

This paragraph from Dr. Jordan's poster illustrates many of the distortions and errors which she makes;

Only vaccinated individuals were found to develop auto antibodies in a landmark study done at Perdue University. Auto antibodies are made with the vaccines from the viruses, from the microbial antigens, from the aluminum and mercury and other ingredients that would mutate or disrupt the pathogen. The increase of molecular mimicry increases with vaccines and these examples of pathways to increase the number of auto antibodies formed the trigger necessary to promote genetic expression of autoimmune disease. Certainly, autoimmune disease expression is one step closer to genetic disease and that handicap will transfer vertically to the next generation in many instances. The important understanding is that the adulteration of the genome came in via the injection of vaccine.

It is true that several scientists at Purdue have done a lot of work evaluating the efficacy and potential adverse effects of vaccination in dogs (examples of their work in references 2, 3, and 4). However, auto antibodies are antibodies which react to normal tissues in the body, and may be formed by exposure to animal protein contaminants of vaccines, and occasionally from injuries to tissues such as the lens of the eye, not normally from viral or bacterial antigens, or by exposure to the small amounts of aluminum or mercury present in some vaccines. Let's see what they have to say from reference 3;

To date, routine vaccination of these Beagles has not caused any overt signs of clinical disease. However, the blood of all the vaccinated dogs contains significantly elevated concentrations of antibodies directed against proteins that are present in commercial vaccines as contaminants of the production process. None of the unvaccinated control dogs has had a similar increase in these antibodies. These proteins are typically of bovine origin since fetal calf serum is used to grow the viruses for vaccine production. The close similarity in structure of the bovine proteins to dog proteins results in a situation whereby the antibodies produced by the vaccinated dogs may cross-react with dog tissue proteins in a process similar to autoimmunity. Experiments in other animal species suggest that these autoantibodies might eventually cause diseases in the vaccinated animals, but these
Beagle dogs will need to be followed longer to determine if this is the case. In addition, the pattern of individual responses of the immune system to vaccination in this study suggests a possible genetic predisposition to autoimmunity.

(this paper appears to have been published online and is no longer available at Purdue's website-this extract was taken from a breeder's website). These results are much more preliminary than Dr. Jordan or some breeders make them out to be, and while they are cause for concern and may be reason to change vaccine production methods, there is no mention of the vaccine directly causing mutations. I have not been able to find any evidence that vaccines cause "adulteration of the genome" which is transferable to the next generation. Perhaps one of the most insidious results of this type of reasoning is that some breeders use it to blame problems caused by inbreeding on vaccination instead. The Purdue paper seems to be commonly misused in this way on many breeder's and "holistic" veterinarian's websites. Unfortunately Dr. Jordan and others are taking a legitimate scientific controversy and distorting it beyond all recognition and far beyond the actual evidence. This quote from Dr. Jordan's personal website's mission statement illustrates in her own words how she has abandoned evidence and science for the ideologically based view she prefers;

It was a decade out of medical school before I clearly saw that the beliefs of modern medicine were simply beliefs and not in alignment with the innate wisdom of the body. Vaccines and drugs are at odds with the intelligence of the almighty design and getting back to the garden means getting back to the natural form and using the optimal nutrition, energetic repair and right relationship of living.

There are many more examples of distorted ideas about evolution and the immune system in Dr. Jordan's poster and website. Since she does not list any references(there are no references on the poster and the references and resources pages on her website are blank), it is difficult to discover where she gets most of her ideas. Many probably come from her own head, and others are from sources I was unable to track down.
In any case, following ideas such as these would be extraordinarily dangerous for pets and humans, indeed far more dangerous than vaccinations have ever been. For an excellent discussion of the relative risks and consequences of antivaccine movements on the human side, see Prometheus' recent post here. It is sad that Dr. Jordan seems more interested in fear mongering and selling books than rationally evaluating the evidence.

References;

1.Journal of the American Veterinary Medical Association

June 1, 2005, Vol. 226, No. 11, Pages 1821-1842

doi: 10.2460/javma.2005.226.1821

The current understanding and management of vaccine-associated sarcomas in cats

2.Journal of the American Veterinary Medical Association

July 1, 2007, Vol. 231, No. 1, Pages 94-100

doi: 10.2460/javma.231.1.94

Adverse events after vaccine administration in cats: 2,560 cases (2002–2005)

George E. Moore, DVM, PhD, DACVPM, DACVIM; Andrea C. DeSantis-Kerr, DVM; Lynn F. Guptill, DVM, PhD, DACVIM; Nita W. Glickman, MPH, PhD; Hugh B. Lewis, BVMS, DACVP; Lawrence T. Glickman, VMD, DrPH

3.Effects Of Vaccination On The Endocrine And Immune Systems of Dogs, Phase II Purdue University, November 1, 1999
Drs. Harm HogenEsch and Larry T. Glickman

‌

4.J Am Vet Med Assoc. 2002 Aug 15;221(4):515-21.

Evaluation of antithyroglobulin antibodies after routine vaccination in pet and research dogs.

Scott-Moncrieff JC, Azcona-Olivera J, Glickman NW, Glickman LT, HogenEsch H.

Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.

"Heads I win, Tails You Lose"

2010-08-24T10:04:00.000-07:00

This is an excellent article by Richard Wiseman on psi research and how studies are poorly designed, statistics are misused, and results are distorted to support psi research. Many of these problems are also common to many types of CAM research and unfortunately, sometimes other medical researh as well, so this is a useful article to keep in mind when evaluating medical claims. Basically, it illustrates many things which pseudoscience and sometimes just bad science does which should be kept in mind when critically evaluating claims.

Raw Milk; the myths and the evidence.

2010-08-09T21:28:00.000-07:00

I wanted to draw attention to a new website dealing with the scientific evidence relating to human consumption of raw milk. There are many claims that raw milk is better than pasteurized milk, most of which are based on anecdotes and testimonials, and not on stronger evidence. On the other hand, there is a lot of evidence that bacterial contamination of raw milk can cause serious illness and even death in humans, especially in susceptible people such as very young children, the elderly, and anyone with a suppressed immune system. While some of the bacteria which commonly occurred in raw milk (bovine tuberculosis and Brucella) have been eliminated from livestock in the United States and much of Europe, there are still several types of bacteria that can cause serious illness, especially in high risk groups. This is important because some of the claims made for raw milk relate specifically to health claims about children which are based on poor or no evidence. Raw milk may be an especially serious risk to urban or suburban children who may have no previous exposure to these bacteria. In contrast, children raised on farms probably receive some passive transfer of immunity from their mothers, and may also be constantly exposed to similar bacteria, allowing them to develop immunity. This does not mean that farm children never experience these illnesses, but the immune resistance of children who live away from a farm environment may be lower to these livestock related bacteria.

Real Raw Milk Facts is a new website written by veterinarians, food scientists and epidemiologists which provides the evidence for claims relating to raw milk and the risks of consuming raw milk products. It has an extensive list of scientific references relating to raw milk related disease. If you or someone you know is considering giving yourself or especially children or other susceptible persons raw milk, make sure that you understand that the evidence for benefits from raw milk is poor to non-existent, and the risks of exposure to dangerous bacteria are much higher than they are with pasteurized dairy products.

The Rabies battle continues, in my backyard and yours.

2010-07-28T20:33:00.000-07:00

I have posted about the new strain of rabies virus associated with bats but also capable of causing outbreaks in other species such as foxes and skunks a couple of times. There have not been many cases reported in carnivores this year, probably due to the wildlife vaccine program which they did last year. This program involves oral vaccines distributed for foxes, coyotes and raccoons, and a trap and vaccinate program for skunks (unfortunately the oral bait vaccine is not effective in skunks for some reason). The dedicated personnel of the USDA wildlife services rabies management program get the lovely job of trapping and vaccinating skunks in Northern Arizona again this summer to prevent the spread of rabies virus from bats into terrestrial animals again.
Currently they are vaccinating skunks in my neighborhood. I found a trap about 100yards away from my house today, complete with a small skunk hiding in the brush near the trap waiting for darkness before traveling away from cover again.

This skunk was very calm and sleepy during the middle of the day, waiting for nightfall to resume it's normal foraging.

The ear tags indicate that this skunk has been vaccinated against Rabies.

This program is an interesting example of how science based veterinary medicine can improve the lives of both humans and animals. Eliminating terrestrial rabies would reduce the risk of exposure for both wild and domestic animals and humans as well. If you have a program like this going on in your area, be sure to express your appreciation of the sometimes unpleasant and nearly always under appreciated work that these people are doing on your behalf.

A new resource for information on stem cell therapies.

2010-07-26T21:23:00.000-07:00

There was a very good NPR story this morning on Morning edition on both the scientific potential of stem cell therapies and the false hope and outright quackery being offered to desperate people by stem cell clinics, especially overseas in places like China. The story did an unusually good job of reporting on the current use of stem cell therapies and the unscientific, premature, and possibly even fraudulent clinics that have erupted all around the world in recent years. They also mentioned a new website started by the International Society for Stem Cell Research that does a good job explaining the state of the science of stem cell therapy, and more importantly has a place for people to submit the names of clinics and stem cell therapy claims for evaluation by experts in the field of stem cell research. This site seems to be oriented toward human stem cell therapies, but could still be useful for veterinary information due to overlap between human and veterinary medicine. The premature and fraudulent use of stem cell therapies in human medicine is a far larger problem than it is in veterinary medicine, but these researchers may also have knowledge of veterinary applications of stem cell research. Once the initial evaluations of human clinics are done, I hope they will look into the veterinary claims as well. The site should be a valuable resource for science-based information in any case and will be worth keeping an eye on as evaluations of clinics are published.

The Monsoon along the Mogollon Rim.

2010-07-18T19:46:00.000-07:00

The Mogollon Rim in north central Arizona rises suddenly to an elevation of about 7-8,000 feet above sea level. This sudden elevation change means that the rim gets more snow in the winter and more rain during the summer monsoon than anywhere but the highest mountains in the state. The area was made famous to the rest of the world by General Crook's campaigns against the Apache in the 1870's, and Zane Grey's writing in the 1920's. The rim has been an important summer hunting and gathering ground for thousands of years. The combination of high altitude and the resulting increased moisture means that water and a variety of plant and animal foods are available on the highlands above the rim when the desert below is sweltering in temperatures well over 100 degrees Fahrenheit. The berries we usually pick are not quite ripe yet, but should be within a week or so, and other interesting plants and animals are active.

A view of the Mogollon Rim from it's crest.

A mountain tree-frog Hyla eximia, one of two tree-frog species in Arizona.

This is the first time I have ever seen one, and I would have missed it among the green leaves if it had not moved when we walked by.

The first edible wild mushrooms of the year.

Oyster mushrooms are fairly easy to identify, and do not really have any toxic lookalikes.

Always be cautious collecting and eating wild mushrooms-consult 2-3 references and someone with experience first.

An unsuccessful attempt to dig a red squirrel out of it's refuge.

New developments with Dr. Alson Sears' NDV treatment of Canine Distemper, and more worrying signs of quackery.

2010-07-05T21:18:00.000-07:00

I posted about Dr. Alson Sears' treatment for canine distemper last year, and there have been some interesting developments since then that I thought should be addressed. There is at least one new person involved who I believe genuinely cares about animals and who seems to be convinced that the treatment of canine distemper involving Newcastle disease vaccine is actually effective. Unfortunately, there is not any better evidence that the treatment is effective, despite two different groups collecting donations to support their efforts to have more dogs infected with distemper treated. Ed Bond, the journalism teacher is still promoting the treatment with his own website and a facebook group, and now someone named Jane, who has her own shelter/rescue operation and writes her own blog and a blog on the Houston Chronicle website is now collecting donations for "Project Hope" which is dedicated to producing Dr. Sear's serum using Newcastle's Disease Vaccine administered to dogs and treating distemper cases with it. While I am still convinced that everyone involved in promoting this unproven treatment means well, and that they truly believe that it works, there are some disturbing signs of "mission creep" in the diseases which they claim to be able to treat, and the attempts to prove the treatment effective look inadequate to provide the kind of proof which they would like. At this time, they are selling DVD's and taking donations to provide what is at best an unproven and experimental treatment, while presenting it as something that is a proven treatment. This raises some serious ethical and legal concerns as most of the dogs involved are coming from shelters, and in some jurisdictions it is not legal to experiment on shelter animals, and spending money on an unproven and possibly risky treatment may not be the most effective use of limited funds.

To review my last post, canine distemper is a viral disease that affects domestic and wild canines and some other wild species such as raccoons and mustelids and large cats such as lions and tigers (cats in the genus Felis-domestic cats, and small wild cats also including american mountain lions are not susceptible to canine distemper). The vaccine is very effective, and despite some problems with effectiveness about 20 years ago (1, 2, 3), canine distemper is very rare in vaccinated, well cared for dogs and puppies. It can be a serious problem in large populations of young, unvaccinated dogs, such as shelter populations. There seems to be an ongoing outbreak in shelters in the area in which I live, and there are apparently similar problems in other areas as well, which may be one reason people are looking for treatment options right now. The course of the disease in an infected dog varies depending on a variety of factors depending on the dog's age, immune/vaccine status, and the strain of virus causing the infection. Young puppies are most susceptible, especially during the period when their maternal antibodies are declining but before they have time to develop their own immune response from vaccination. The highest risk period is from 6-16 weeeks, but unvaccinated dogs can be infected at any age. Older dogs tend to have somewhat less severe infections and a higher survival rate. Once dogs do develop immunity, it is long lasting, 3-4 years at least (1, 2, 3). Severely infected dogs are susceptible to secondary, fatal infections such as bacterial pneumonia, and some dogs develop neurological complications that can cause seizures, paralysis and death. Sometimes these problems can occur months or even years after apparent recovery from the infection, and are caused by damage the immune system does in the nervous system while trying to get rid of the virus. It is difficult to predict when or if a dog with a mild or moderate case of distemper will develop neurologic symptoms.

Diagnosing distemper definitively can be more difficult than we would like. Indirect tests such as looking for distinctive inclusion bodies in cells collected from various locations are good, and PCR testing for viral antigen is better, but the standard PCR test does not distinguish between the modified vaccine virus and the wild strains, and it is unknown how often the vaccine virus causes inclusion bodies in cells. This means that vaccination can cause a positive test result for up to three weeks after vaccination. I don't doubt that most of the dogs being treated by these well-meaning people do have distemper, but it is certainly possible that some of the dogs who recover quickly have other types of infections and test positive because of vaccination. Most shelters vaccinate puppies as soon as they enter the shelter in an attempt to avoid problems, so many of these puppies may have both vaccine and wild virus in their systems at the same time. Other infections like bacterial respiratory infections, canine influenza, and other viruses can all cause similar symptoms. Symptoms consistent with distemper and positive tests make it very likely that these dogs do have distemper, but specialized viral testing would be required to definitively prove that the dogs who recover did in fact have distemper and that the treatment actually killed the virus as Dr. Sears claims. This type of testing is normally only done in some virology research labs and at places like the CDC, where they analyze new strains of influenza and serious, unknown outbreaks of disease. Specialized immunology labs would also be required to confirm that the newcastle disease vaccine is having the effect Dr. Sears claims it has, which is stimulating a strong immune reaction in the donor dogs, such that a few milliliters of serum is enough to kill all the virus in an infected puppy.

There seem to be signs that the proponents of the treatment are using some selection bias when reporting the results of the treatment, and overstating the number of dogs which survive. I will provide some quotes from their sites that seem to illustrate this. Project Hope is named after a puppy that did not survive the treatment, and there seem to be quite a few similar cases when I searched through the discussion pages of the facebook group;

The serum treatment for distemper is nearly 100 percent--I don't know of any cases that failed but in medicine, there is never 100 percent of anything.
(May 5th, 2010 Jane's blog)

This is almost 6 months after "Hope" died despite treatment, and after other failures;

SaveDogs FromDistemper Sadly all 5 Croatian puppies died, but the adult with neurologic symptoms has recovered. They are calling it a miracle.
(December 19, 2009 at 7:17am Facebook Group)

There are others as well when you scroll through the discussion pages.

Since distemper is such a serious disease, dogs who recover often have an extended recovery. Despite claims that the Newcastles treatment is so effective, they have many cases where the dogs take a long time to recover. This (and their failures) is blamed on the secondary infections, or the treatment coming "too late", which is unfortunately something which happens all too often in defense of many unproven treatments.

She is a Project Hope serum puppy. Three weeks ago, after being diagnosed with distemper at her vet, Brindy received Dr. Sears' NDV-induced serum, a treatment for distemper. She had an advanced case of distemper--green crusty nose, green crusty eyes, pneumonia...and she had a skin condition of some sort. The distemper was dead in 24 hours according to Dr. Sears. The other issues have yet to be cured.
(Feb. 15, 2010 Jane's blog)

Skin problems can be caused by distemper as well.

It will take some weeks or even months (4 weeks to 4 months is what Dr. Sears tells me is a good rule of thumb) for the damage that was done to repair itself. (March 19, 2010 Jane's blog)

They are also starting to make claims that the treatment works for a wide variety or other dieseases, with apparently no evidence whatsoever. Occasionally they contradict themselves, as Dr. Sears says at one point in a video clip that the serum does nothing against parvovirus, but claims otherwise elsewhere.

Dr. Sears is now including the NDV-induced serum in protocols to treat not only canine distemper, but parvo and herpes as well as several other diseases. The first puppy testing positive with parvo had serum and within just several days, her fever went down and her recovery seems to be rapid. This is making me think some.

First of all, having the serum is like having a life-insurance policy for our dogs/puppies. As long as we act fast enough, and don't waste weeks with other vets getting ineffective treatments, the serum is very close to miraculous. If I didn't know that serum was in Houston, I would be very nervous about the outbreaks of distemper and parvo.
(April 3, 2010 Jane's blog)

What is fascinating, is that this same disease model--what Dr. Sears' is using to treat distemper--can be used to eliminate human diseases like MS and maybe even cancer. Yes, this is huge--and we have to do a little bit each day. What we are learning and teaching, thanks to Dr. Alson Sears, will make a difference in this world.
(Feb 15, 2010 Jane's blog)

Those are pretty remarkable claims, and I am sure Jane really hopes and believes they are true, but it does not seem to bode well for the scientific attitude toward the treatment they are promoting.
They seem to want to prove that the treatment is effective, which is a good thing, but they don't seem to have anyone with any scientific training working on it. Their claims of ties to Texas A&M seem to be limited to sending their diagnostic tests to the lab there. At this point there is no indication of involvement of the veterinary school there in researching this treatment.

This will be a publicly-funded project (donation-sponsored) and the serum will then be free to those who need it--and agree to participate in the screenings for distemper which are being sent to, and tested by, Texas A & M. It is our intention to get a peer-review article for vets all over to learn from what we are doing. How often do we get a chance in our lives to do something that can change the world?

(February 28, 2010 Jane's blog)

In conclusion, the evidence of their own websites, and the fact that they seem to be using the donations they receive honestly, indicates that Ed Bond, Jane, and others involved in this are honestly trying to help sick animals. Unfortunately, after 40 years of using this treatment, Dr. Sears still has nothing more than anecdote and testimonial to prove that the treatment works. While he has managed to convince some well meaning laypeople, the evidence is still inadequate to non-existent, and of all the people involved in this, he is the one who should understand this. Apparently he does not. If this treatment is ineffective, the effort and money they are spending could be much better used elsewhere. I would be happy to be wrong about this, but so far they have not presented anything to convince me that I am. If they really want to show that the treatment is effective, they need to establish that the treated dogs all actually had wild strains of distemper, and their tests are not being interfered with by vaccine strains of virus. Ideally, they could run a blinded, controlled trial to be sure that treated dogs survive distemper at a higher rate than dogs given standard, supportive care. They also need to keep meticulous and honest records of both positive and negative outcomes. It might be difficult to convince everyone involved to do this, since the primary promoters of the treatment already seem convinced that it works, and may be reluctant to not treat some dogs in a trial. However, if they really want to know if this treatment is effective, and produce evidence that other veterinarians would accept, that is what they need to do, even if the results are disappointing in the end. It is possible that the treatment is a false hope, which would be worse than the small hope available now to owners of severely infected puppies. If the treatment is ineffective, as I suspect it may be, then they can concentrate on helping dogs in more effective ways.

Addendum; 7/28/10;
For those who might be interested in another, science-based resource on shelter medicine and issues such as distemper problems in shelter animals, the UC Davis Koret shelter medicine program has an excellent website with a page on canine distemper. Related to the outbreak local shelters are experiencing, the use of the relatively new recombinant distemper vaccine produced by Merial can be useful as it does not cause false positive PCR tests. The use of this vaccine by those trying to demonstrate efficacy of Dr. Sears' treatment would be one thing that would help to increase the validity or their results.

Flagstaff Summer Film Festival

2010-07-02T22:11:00.000-07:00

For anyone in Northern Arizona, or anyone who would like to spend a little time in the beautiful summer weather of Flagstaff, Arizona this August, here is an idea; The first annual Flagstaff (Summer) Film Festival.
The founder has chosen a lot of interesting independent films (partial list available here) many of which have themes relating to science or skepticism, including alternative medicine, border and immigration issues, and other topics.

Hope to see you here!

Veterinary Nonsense on the Huffington Post.

2010-06-09T21:46:00.000-07:00

The Huffington Post is home to some of the most ridiculous and idiotic writing on human alternative medicine, and now, not to be left out, the have a veterinarian writing on "integrative" veterinary medicine. A recent post by Dr. Richard Palmquist brings veterinary integrative medicine into the world of woo that is the medical and lifestyle pages of the Huffington Post.

He begins with a statement of his scientific background;

My parents were science-based people: my mother was a dental educator and my father was a microbiologist. Many of my friends were children of members of the medical community. These people were my heroes and not one of them did "crazy, voodoo crap like acupuncture, homeopathy, herbs or reiki." These people did "modern medicine," which came from science and used the best of our knowledge to help people. I was, and still am a science guy.

Apparently he forgot to pay attention to his heroes, and in science class as well, because he proceeds to interpret anecdotes, testimonials and possibly outright fraud as scientific proof that various alternative medicine techniques actually work. He also discusses bias in a twisted way. It is true that prejudices can lead to premature judgments, but it does not mean we should accept anything based on the kind of evidence he presents in his article. being open minded is a good thing, being so open minded that you stop thinking critically, or even stop thinking at all is just as bad as any other bias that can affect our thinking. He goes on to present several anecdotes to prove his point, but to anyone who does utilize critical thinking, the flaws in these stories are fairly obvious.

The first anecdote is about a discussion he had with an alternative practitioner;

I said, "I understand you cure cancer." I knew this question would expose him for the fraud I knew him to be. He responded, "No, absolutely not. We don't cure cancer. Frankly we don't even treat cancer. What we do is support individual patients' immune systems and sometimes remarkable things happen."

This is pretty remarkable; the veterinarian admitted that he did not treat cancer, but then makes the fairly meaningless claim, common to many evidence-free treatments, of "supporting the immune system". Mark Crislip has an excellent post about supporting or boosting the immune system here .
He then proceeds to discuss cases where he thinks cancer was cured by alternative methods.

Then he presented a case complete with documentation from the top referral small animal hospital in New York. This case was a cat with a massive brain tumor diagnosed with state of the art brain imaging and found to be too severe for treatment. The cat was blind and semi-comatose on presentation to his office. After receiving dietary therapy the cat regained its sight and later had new x-rays taken only to reveal the tumor was 50 percent smaller. I had never seen anything like that before.

Top hospital or not, Dr. Palmquist knows that an image, no matter how high-tech, of a mass is not a diagnosis of a tumor. It is a picture of something which may be a tumor, an infection, or even an artifact that only looks like a mass. Either he is leaving out many details (was the mass biopsied, was the cat treated with any other evidence-based treatments, etc.) or he is not asking the scientific questions he should be asking.
The next anecdote is another cat with a tumor;

On Monday I went to his clinic to observe him work. The first case was a terrible oral tumor that was recovering after receiving cryosurgery -- freezing the tumor to kill it. I had not seen this type of surgery for this kind of disease before and was amazed at how well the cat was doing. I also noticed the intensely honest communication and loving connection he had with both the people and then cat. My heart melted a bit.

This is another common tactic of alternative practitioners; co-opting science based treatments and calling then alternative. Cryosurgery has been used to treat many different types of tumors and other lesions for many years. It may be true that Dr.Palmquist had not seen it used to treat oral tumors, but it really should not have been such a surprise. Cryosurgery was commonly used for many years before Dr. Plamquist's epiphany. Honest (debatable) and loving communication is also not limited to alternative practitioners. The next case also should raise some red flags, but apparently by this time Dr. Palmquist was so ready to believe anything that he fainted;

The next case was a paralyzed German shepherd dog which was treated by top specialists. The dog was carried in on a stretcher and a neurological exam showed the dog to be
non-functional. I knew after such a long time that euthanasia or hopeless surgery was the only option, but the "likable quack" began applying acupuncture needles to the dog. The dog lay there happily, and then the needles were removed at which point the patient simply got up and walked over to the owners.

Extraordinary claims require extraordinary evidence. Either Dr. Palmquist was cruelly played, or he is again using weasel words to imply more that what actually happened. If the dog was really non-functional and was "cured" so quickly using acupucture, that really would have been remarkable. Again, what does "non-functional" really mean? The story sounds amazing, but many questions need to be answered before we accept the claims made here.

Since Dr. Plamquist's conversion to integrative medicine, he has apparently published many case reports, which are really just formalized anecdotes, and are not scientific proof of much of anything, and has written a textbook on integrating alternative medicine into veterinary practice. He is apparently a proponent of the pseudoscience of homotoxicology, and is the president elect of the American Holistic Veterinary Medical Association. The kind of fuzzy thinking Dr. Palmquist has demonstrated in his post does not inspire confidence in the scientific rigor of his association.

Addendum; Steve Novella has an excellent post today demonstrating the harm that can come from honest, caring and well-meaning quackery.

Battlefield Ridge-a microcosm of Arizona nature and history

2010-06-07T19:31:00.000-07:00

Battlefield Ridge extends north from the Mogollon Rim for about 8 miles, and ends between East Clear Creek and Bear Canyon, one of many canyons in the East Clear Creek watershed. The ridge is named for the Battle of Big Dry Wash, which happened on July 17th, 1882, and was the last battle between members of the Apache tribal groups and the U.S. Army on Arizona soil. (Most online accounts of the battle appear to repeat errors in the timing and sequence of events of the battle-the most accurate and well-referenced description is in Dan Thrapp's book; Al Sieber, Chief of Scouts which is unfortunately out of print, but is available in many libraries.) One Cavalry trooper was killed, one apache scout was killed, possibly by friendly fire, and approximately 20 "renegade" apaches were killed in the battle.
The Canyon was later dammed, forming Blue Ridge Reservoir, which serves as a water source for the mines in Globe. Ironically, exploitation of mineral deposits in places like Globe and Jerome were one of the major reasons that the Apache were being forced onto reservations and off their traditional hunting, farming, and raiding lands in the 1870's and 1880's.

In the last century this area has been grazed, logged, and natural fires have been suppressed, resulting in a denser forest of smaller trees instead of the open, park like pine forest that covered most of the area in the 1880's. In spite of this many of the rugged canyons in the area are in fairly pristine condition, and still have most of their original flora and fauna.

The pictures below are from the area where the battle occurred, and illustrate the traces of the battle still remaining, and the natural beauty that persists in the area to this day. (click for full sized versions)

The front side of the monument.

The back side of the monument, listing the troopers and Apache scouts present.

The only grave at the battlefield is Pvt. Joseph McLernon's. The Apaches who died in the battle were not buried, and were left where they fell. There is no record of what happened to the Scout who was killed.

The lower end of the ridge where the Apaches made their stand now lies under the waters of Blue Ridge Reservoir, which is often this green color due to algal blooms.

The view across the side canyon. The initial army positions were here, and the Apache group was on the ridge that is now barely visible through the trees.

This columbine, Aquilegia desertorum grows in the limestone crevices and ledges of the area

A small bird bolted from under the rock just under this fence as I approached.

The nest, eggs, and first hatchling are hidden underneath.

Crackerbox canyon, about a mile southwest of the battlefield is named because of the empty hardtack boxes the army left here when they camped after the battle.

A cow elk or wapiti grazing on the lush growth of the creek bottom.

At least one bear has been foraging on the early growth as well.

A dead pine and a red-tailed hawk are the only sentinels now.

The bears may soon have wild strawberries to eat.

Acupuncture still does not work very well.

2010-05-30T18:54:00.000-07:00

As Harriet Hall, the SkepDoc likes to say,

Studies have shown that acupuncture releases natural opioid pain relievers in the brain: endorphins. Veterinarians have pointed out that loading a horse into a trailer or throwing a stick for a dog also releases endorphins. Probably hitting yourself on the thumb with a hammer would release endorphins too, and it would take your mind off your headache.

Ed Yong has an excellent post about the latest science relating to acupuncture. While there is a physiological response locally and in the central nervous system when the skin is punctured or stimulate with needles, there is still very little evidence that these effects have any positive effect on the progression of any disease. It is troublesome that acupuncture is still being promoted by veterinarians as an effective form of pain relief for everything from surgery to arthritis. Since our animal companions cannot really tell us if they want or enjoy acupuncture, we should be very cautious with dramatic but probably ineffective interventions like acupuncture
that may have more effect on the psyche of the owner than on the patient. The acupuncture archive at science-based medicine is also well worth a read if you have not already.

The sad case of Macho B

2010-05-20T21:45:00.000-07:00

AZ Game and Fish

This story has received quite a bit of attention in Arizona over the last year or two, (here, here, here and here are some examples in chronological order, also here) but may not be that well known outside Arizona. There is also a veterinary issue I would like to address that has not really been mentioned yet but that relates to this case and potentially many others. There are also some political issues that relate to large wildlife migration and border issues (fences, patrols, and other human activity), but may relate to the motivations of some of those involved. Political resistance to consideration of endangered species use of borderlands and impacts of things such as security fences on endangered species may have contributed to bypassing federal regulations in this case.

In summary, Macho B, an older adult male Jaguar was known to be living in an area of southern Arizona, and was "inadvertently" trapped Feb. 18th, 2009, and collared as part of an ongoing study of bears and mountain lions. 12 days later data from the collar showed that Macho B was not moving as much as he should be, and he was recaptured and taken to the Phoenix Zoo for evaluation. Blood tests done at that time suggested kidney failure (elevated BUN and Creatinine) and the Jaguar was euthanitzed that day. Pathology results from necropsy indicated that he may have been suffering from fairly severe dehydration rather than renal failure, and the decision to euthanize may have been precipitous and premature. Later investigations showed that the initial capture was not accidental, as several people knew that female jaguar scat had been placed at several snares to attract Macho B. This was done without the proper permits from or knowledge of federal or state wildlife agencies. Since then, one state game and fish officer has been fired, last week Emil McCain, the biologist from the Borderlands Jaguar Detection Project plead guilty to intentionally trapping the Jaguar in violation of the Endangered Species Act, and charges have been filed against another technician. It also appears that Emil McCain has been involved in several other capture related jaguar deaths in Mexico and Central America, which raises questions as to his competence in anesthetizing big cats.

The veterinary related issue I would like to address is the way many biologists and some veterinarians are trained to immobilize wild animals, and a problem which seems to be more severe, if not unique to the United States and/or the Americas, which is the lack of utilization of veterinarians when wildlife is anesthetized, and possibly a general lack of cooperation between wildlife biologists and veterinarians. While practices vary from state to state (some state wildlife agencies have veterinarians on staff while others do not, and someone working on a research project may work for a university, or various state or federal agencies that have varying policies and availability of personnel) it seems to be very common for wild animals to be anesthetized without direct veterinary supervision by people of varying training, experience and competence. Anesthesia always carries a risk, and anesthetizing a wild animal where exact weight and health status are unknown increases the risk of adverse effects. Sometimes this risk is justifiable-for example, wildlife may wander densely populated areas where they could pose a danger to people or are in danger themselves, and game wardens may need to immobilize an animal and move it in a hurry. On the other hand, planned captures for scientific studies or preplanned management activities do not justify the same level of risk to the animals. In Macho B's case, the people involved were already ignoring regulations and will pay the price, but there are fairly frequent cases of animals dying during immobilization. While "bad reactions" can happen, true allergic or other adverse reactions to anesthetic drugs are actually fairly rare, and saying an animal had a bad reaction may be due to human error such as an error in dose, or failure to recognize common problems such as low blood pressure, respiratory arrest, dehydration, and hyper or hypothermia. While a biologist is certainly capable of learning and practicing wildlife anesthesia, and veterinarians certainly can make the same mistakes, calculating doses and recognizing and dealing with complications benefit from both double checking and practice. Training programs for animal control, wildlife managers and biologists are often very short, and may not involve any supervised practical experience after the training session. In contrast, veterinary students spend many more hours learning relevant physiology and pharmacology, usually a couple of weeks of classroom instruction specifically relating to anesthesia, and usually several weeks at least of supervised practice on living, client owned animals in veterinary teaching hospitals. Veterinary anesthesiologists spend another 3-4 years to become board certified specialists. While a weekend course might be acceptable for animal control officers and game wardens who are only going to use chemical immobilization as a last resort in emergency-type situations, more training and some level of competence should be expected when animals are immobilized or anesthetized for less urgent reasons.

The other aspect of this topic that may relate to attitudes and problems in cooperation is the relationship between basic scientists (wildlife biologists, etc) and veterinarians at some universities seems to be slightly strained. While I was in veterinary school, there seemed to be an attitude that anyone with only a PhD was not qualified to teach veterinary students anything, and conversely veterinary instructors did not want to teach students outside the veterinary program. I have also seen biologists at other universities who seemed not to recognize or even resent the contributions veterinarians could make to their research. I have no idea how widespread this type of attitude is, but I suspect it may contribute to problems with immobilizing and anesthetizing wildlife. In Macho B's case, the initial capture was unfortunately carried out illegally and inappropriately. It lead to a series of events that probably also included veterinary errors that resulted in the animal's premature death. Perhaps better cooperation between veterinarians and wildlife biologists could help to prevent unfortunate outcomes in the future.

Signs of Spring in the mountains.

2010-05-16T18:59:00.000-07:00

We had a little snow last week, but it is actually warming up enough for the plants and wildlife to start coming alive again. Here are a few pictures of harbingers of spring in the mountain west.

The hummingbirds show up as soon as there are few flowers (currants and gooseberries this time of year). Amazing that they survive the subfreezing nighttime temperatures we are still experiencing at night.

Bullock's Orioles are another visitor to the hummingbird feeders, and nest in the neighborhood.

Canyon tree frogs breeding in temporary pools.

Canyon tree frog habitat.

The Elk are shedding last year's antlers in preparation for growing a new set.

Snakebite Fact and Fiction

2010-04-24T21:54:00.000-07:00

http://www.flickr.com/photos/28113115@N00/ / CC BY-NC 2.0

With spring in the northern hemisphere, the warming weather brings the rattlesnakes out of hibernation. According to Arizona poison control, they have received 11 calls this April for Rattlesnake bites, four of which were dogs. I thought it might be an appropriate time to discuss snakebite fact and fiction, especially relating to first aid and animal treatments which might be found on the internet. Venomous snakebite is a fairly common occurrence around the world, and often happens in remote, inconvenient locations. This has resulted in the development of many first aid techniques and remedies that may be ineffective or dangerous. In addition, the sporadic, variable, and serious nature of snakebite makes controlled studies of even science-based treatments difficult. I will attempt to review the basic science of envenomation and what first aid and preventative treatments may be reasonable, which are not, and what treatments are effective and reasonably science-based.

There are over 600 species of venomous snakes around the world, and there is a lot of variation in the toxicity or venom between species, and even between snakes of the same species. Venoms are a complex mixture of proteins and peptides that act as enzymes that damage tissues and blood, interfere with blood clotting, and act as neurotoxins to immobilize and kill prey. (The evolution of and variation in venom is an interesting topic on it's own.) The primary purpose of venom is to immobilize, kill, and help digest relatively small prey such as small mammals, fish, amphibians and other reptiles. The toxic effects are painful and debilitating enough to larger animals that the venom also creates a good defense. Many venomous snakes have some type of warning display (distinctive colors, rattles, hoods, etc) to warn and deter predators or other large animals that might stumble upon the snake. Unfortunately, many snakes such as most pit vipers are often well camouflaged and do not always rattle or otherwise warn of their presence. Because of this, even dogs that are "snake trained" can still accidentally step on a quiet snake and be bitten. Snake training for hunting dogs and dogs that live or enter snake habitat may be useful when done by experienced trainers, but is no guarantee that the dog will never be bitten.

Several aspects of snakebite have the potential to make various first aid measures look more effective than they may be. The fact that the patient survives or recovers quickly is not evidence that many first aid measures are effective. While all venomous snakebites have the potential to be deadly, most victims in North America survive (some species such as most elaphids like many Australian snakes, cobras, and coral snakes have more neurotoxic venoms than most vipers such as rattlesnakes, which tend to have more cytotoxic venoms this can affect the mortality rate for snakebite drastically in different parts of the world). Most of the deaths from snakebite in the United States relate to delays in seeking or receiving treatment. There are several reasons many snakebites are not as deadly as they are often perceived to be. The first is that many snakes inject little or no venom when they bite. Snakes "want" to escape and save their venom for catching and consuming prey, and if a warning dry bite will allow them to escape, then that is what they will do. A second reason is that there is quite a bit of variation in the toxicity of venom between different species of snakes and even between individuals of the same species because of age, size, and other factors. Also, some non-venomous or mildly venomous snakes mimic venomous species and will bite, but do not have very toxic venom or any venom at all. This means that some snake bites may be misidentified as venomous when they are not. It is often not advisable to attempt to catch or kill a suspected venomous snake as this can result in another bite. Because of misidentified bites, and bites that are from venomous snakes, but the snake releases very little or no venom, a significant number of snakebites are not as serious as they might first appear, and these bites can make first aid measure look more effective than they are.

Medical treatment;
The primary medical treatment for envenomation is treatment with antivenom (also spelled antivenin) and supportive care to treat the shock and complications caused by the venom and sometimes allergic reactions to the antivenom. Antivenom is produced by injecting small amounts of venom intravenously into an animal (usually horses, or sheep). over time and many injections, the animal develops antibodies to the proteins and peptides that make up the toxins in venom. Serum is collected and the antibodies are freeze dried for use as antivenom. Antibodies to the venom from a specific species are the most effective for treating bites from that species, but often antivenom is made using venom from several species. This is called polyvalent antivenom. In North America antivenom is usually polyvalent crotalidae antivenom, which is made with venom from several species of rattlesnake from north and central america and is effective for treating any species of rattlesnake bite. There is some variation in venom, and snakes such as the Mohave rattlesnake have more neurotoxic venom than most other rattlesnakes, and may not respond as well to polyvalent antivenom as well as bites from some other species. Crofab antivenom approved by the FDA in 2001 is made using mojave rattlesnake venom and is more effective against mojave venom than older antivenoms. Crofab is very expensive and is rarely used by veterinarians. The situation is different in different parts of the world. In Australia, a test is available to confirm if venom is present and what type of venom. This allows the use of antivenom specific to the bite, and conserves the more expensive polyvalent antivenom.

Other treatments such as intravenous fluid therapy may be used to help keep patients hydrated and to treat shock and fluid loss associated with the bite. Antibiotics may be used to treat secondary infections which may be common in bites from rattlesnakes which damage tissues. These treatments do not directly affect the venom the way antivenom does, however. Since antivenom contains animal proteins, it can cause acute or delayed allergic reactions which are treated with antihitamines and steroids. Again, these drugs are useful for complications from the antivenom, but do not affect or treat the venom itself. Some veterinarians treat snakebites with fluids, antibiotics and steroids when antivenom is not available or when it is beyond the owner's means, but the steroid portion of the treatment is probably not effective and may even be harmful in some cases. This may also be kept as part of the treatment protocol because steroids are often given to prevent reactions to the antivenom, and veterinarians who do not treat snakebite often may remember the use of steroids without remembering why they are used (for reactions to antivenom) in the heat of the moment.

Rattlesnake vaccine
There is a rattlesnake vaccine available in the United States that is provisionally licensed for use in dogs by the FDA. This is neither a treatment nor a first aid method, but is designed to stimulate antibody production to snake venom-in effect creating "anitvenom" in the dog's bloodstream prior to any bite. This vaccine has been demonstrated to produce antibodies capable of neutralizing venom in laboratory tests, but has not been tested in deliberate "challenge" trials, and probably will not be. The vaccine is produced using western diamondback venom, and provides variable effectiveness against other species. High doses of venom can still overwhelm the antibodies produced, so the vaccine is no guarantee of survival. The company claims that the antibodies produced in an average sized dog are the equivalent to 2-3 vials of antivenom, which is often enough to treat many bites. Due to the expense and sometimes limited availability of antivenom for veterinary use, this vaccine might be worth using if your dog is at high risk for rattlesnake bite. Dog that live in rattlesnake habitat or who hike or hunt in areas with rattlesnakes might be dogs that would benefit. It is certainly not necessary for dogs that never leave town and are not likely to encounter snakes. I have heard some rumors of some veterinarians charging hundreds of dollars for this vaccine-the vaccine is fairly inexpensive and should not be much more expensive than any other veterinary vaccines.

First Aid-what may work and what does not.

Tourniquet/pressure bandage;

One of the oldest first aid measures for snakebite is the use of a tourniquet to keep the venom from spreading from the site of the bite. This is not recommended for several reasons. If the tourniquet is left in place too long, the loss of blood supply can damage or kill the limb even in the absence of venom. In the case of bites from snakes such as rattlesnakes and other vipers with cytotoxic venom that damages tissue, a tourniquet can increase the damage caused by the venom, while adding damage from loss of circulation. In the case of snakes with neurotoxic venom such as elaphids (most australian snakes, cobras, coral snakes, and a few others) an immobilizing pressure bandage may be useful. If you are not sure about the type of bite, it is probably better not to use this type of bandage, especially in the North or South America, where rattlesnake bites are much more common than coral snake bites.

Suction;

picture from wikipedia snakebite page.

Another old first aid treatment is suction of the bite. Older snakebite kits such as the Cutter kit pictured above (I had one of these when I was a kid-fortunately I never had an opportunity to use it.) often contained a scalpel blade and a string tourniquet. Making incisions increases the chance of infection and runs the risk of serious bleeding from cut blood vessels, or nerve damage, and does not really help remove venom. The tourniquet has the problems discussed above. These older kits also came with the rubber suction cups pictured that did not really provide very effective suction. A newer version of this type of kit is the Sawyer Extractor. This kit has the advantage of providing much stronger suction and does not contain a scalpel blade or a tourniquet. However, it is still not very effective in bites where the venom is deeply injected below the skin surface and may cause more localized tissue necrosis. It may be difficult to use on animals due to their furred skin interfering with the suction seal. This kit is fairly cheap ($15 U.S.) and may be useful for minor injuries like bee stings, but don't count on it to remove significant amounts of venom. If you do use it, apply it within the first minute or two of the bite and don't leave it in place for more than a few minutes at a time. Also don't waste time fiddling with it if it will delay getting to the vet or hospital.

Electric shock;
One first aid method that was briefly popular in the 1980's was electric shock to the area of the bite. This usually involved shocking the area of the bite with various devices ranging from 12 volt automotive batteries to stun guns. Probably because of mild bites, there are anecdotal reports of effectiveness, but this method can result in electrical burns and damage to tissues, and does not seem to have any effect when tested under controlled conditions.

Vitamin C;
Another old treatment that has been around for a long time is the injection of large doses of vitamin C. This seems to date back to the 1930's soon after the chemical structure of vitamin C was worked out, and it was being promoted as a cure for anything from tuberculosis to cancer. It is still a popular remedy and can be found on many veterinary homeopathic naturopathic and other alternative medicine(quackery) sites. It also seems to be popular in Australia for some reason, possibly due to many farmers and pet owners living some distance from veterinary services and desiring an inexpensive and quick remedy to give. Various sites recommend giving large doses of vitamin C orally, intravenously, or intramuscularly. There is no real reason that large doses of Vitamin C should counteract snake venom, and this interesting site shows a series of cases in a goat herd, where the farmer carefully recorded the effects or lack thereof, of vitamin C injections in animals suspected of being bitten. Interestingly, several cases that survived turned out to be from non-venomous snakes, or "dry" or mild bites from venomous snakes or problems unrelated to snakebite. The animals confirmed to have serious snakebite died despite vitamin C injection. Vitamin C is acidic and is very painful when injected intramuscularly, and in at least one of the goats reported above, apparently caused sterile abscesses to form after the injections. Again, this treatment is not really any better than placebo, and may be harmful in some circumstances.

In conclusion, most first aid treatments for venomous bites are ineffective or minimally effective, and sometimes can cause injury themselves. Don't spend too much time trying to apply first aid to a victim of venomous snakebite. The best chance for humans or animals in such circumstances is getting to professional medical care as quickly as possible. As a friend of mine who is an expert in primitive desert survival techniques and wilderness first aid says, "the best first aid for snakebite is your car keys". Getting to a medical provider who can evaluate the severity of the bite and administer antivenom if necessary is the best thing to do in this unfortunate situation. Time spent trying to apply ineffective first aid, or even worse, self treating with vitamins or some other "natural" remedy can make the difference between surviving the bite and dying from it, and not in a positive way. Snake venom is natural too, and is one of the most toxic substances found anywhere.

BCA drops case against Simon Singh

2010-04-15T07:43:00.000-07:00

The BCA has finally realized how disastrous continuing their libel suit against Simon Singh is, and had dropped it. Simon will probably try to recover his costs, which have been substantial, but this is very good news for Simon and for the cause of libel reform in England.

Details here and here.

edit; and this excellent post at Quackometer.

The appeal to antiquity-a traditional fallacy.

2010-04-12T21:29:00.000-07:00

"The older a treatment the more respect it was given. The Greek historian Dordorus, who visited Egypt in the First century BC, wrote that the doctor who followed a text exactly would not be blamed if the patient died, but if he disregarded it and the patient suffered he could even be sentenced to death."

source ;Charles Freeman, Egypt, Greece and Rome, Civilizations of the Ancient Mediterranean, second edition, 2004, Oxford University Press, pp. 86.

One of the first things we learn as children is to listen to our parents and other older relatives. This is a good thing for a young child, who cannot yet understand which actions may be safe and which may be dangerous, but in the practice of medicine and science can stifle advancement and new knowledge. This is a problem with the apprenticeship/rote memorization model of veterinary medical education, but is an even greater problem in the promotion and use of many CAM treatments. While traditional medical practices are interesting, and sometimes even manage to hit upon effective treatments, they are invariably bound to pre-scientific notions which often have little relation to the actual causes of disease. The lack of real understanding of most diseases that was common to all cultures until recently led to various philosophical models of health and disease that often involve some type of vitalism-treatments are designed to bring some vital force or energy back into balance. Often this involved using plants, animal parts, or other substances which look like parts of the body or the elements of the vital force which need to be changed, or draining blood or other body fluids to adjust these perceived balances. Some of these treatments were harmful (bleeding, treatments involving heavy metals and other toxic substances, etc), some were harmless but ineffective, and a few were effective just by chance.
As I discussed here, ineffective treatments may be more likely to spread in a population than effective treatments.

Promoters of various forms of traditional alternative treatments often make the claim that the treatments they use are ancient when their relationship to actual ancient practices may be dubious. Another oft-heard claim when traditional practices are criticized is that such criticism is prejudiced and racist. This accusation relates to post-modernist beliefs that there are many, equally valid "ways of knowing". While this approach has some value in the humanities, it does not provide much value when trying to answer a scientific question such as whether a medical treatment is effective or not. Claims of racism or prejudice also minimize the contributions of scientists in varying cultures who may be studying traditional treatments such as herbal remedies for safety and effectiveness, or to discover and develop new compounds that may be useful drugs. Since so many traditional treatments are likely to be minimally effective, ineffective, or even dangerous, it is reasonable to demand strong evidence of effectiveness before adopting them, no matter which culture the remedy comes from. Equal opportunity skepticism is not racism, it is what is required to evaluate any traditional treatment.
Some traditional treatments such as bleeding, or treatments involving "magic" or the manipulation of unmeasurable energies, may be useless at best and actively dangerous at worst. Others, such as the use of Milk Thistle extracts as a liver tonic, have demonstrated some evidence of efficacy for some of it's traditional uses.

The appeal to antiquity is as old as antiquity itself, but should not be used to stifle critical evaluation of ideas.

World Homeopathy Awareness Week

2010-04-10T10:05:00.000-07:00

Does homeopathy work?

No. there is nothing but water or sugar in most homeopathic remedies. It is, however, one or the most elaborate and imaginative placebos around. Save your money and don't buy the "magic" water or sugar pills.

Any questions?

More ovaries...

2010-03-08T19:27:00.000-08:00

In a recent post I discussed a paper that claimed to show that dogs lived longer if they kept their ovaries, despite a lot of evidence to the contrary. This article got an inordinate amount of attention in the secondary literature and the blogosphere, most of it quite uncritical. With this kind of observational study, it is easy to analyze the data in a way that will give a positive result, or even to design the study in such a way that a positive result is nearly guaranteed, as discussed here, and here.

In the most recent issue of JAVMA, there is a paper that provides an interesting counterpoint to
the earlier paper. This paper discussed dogs (and two cats) that had residual ovarian tissue left after spay surgeries. Most of these animals had ovarian tissue left in the normal anatomical position for ovaries to be, indicating that failure to identify and remove the entire ovary at the time of surgery is much more common than ectopic ovarian tissue is (I have seen one cat in 20 years that had one normal ovary and no identifiable grossly visible tissue on the other side, but had a couple of weak heat cycles after surgery, then nothing). So the vast majority of these cases can be blamed on careless surgical technique, not exceedingly rare anatomic anomalies. It was also interesting that surgical experience was not a factor, again indicating that complacency and sloppiness was to blame rather than inexperienced surgeons.

This paper had a limited number of cases (19 dogs and 2 cats), so I don't want to make too much of it, but it was interesting that this small paper supported other findings that removing ovaries can prevent certain types of cancer and infections in dogs. In addition to the expected signs of estrus (which are usually not something most pet owners want to deal with) there were five ovarian tumors, seven enlarged uterine remnants, one vaginal mass and two mammary masses. On histology and culture, there were five cases of ovarian cancer, eight cases of cystic endometrial hyperplasia, and one uterine stump pyometra. It is interesting to note that this rate of ovarian tumors is much higher than that reported for sexually intact female dogs (23.8% vs 6.8%). This may be an artifact of the small sample size, but it could indicate that leaving ovaries instead of removing them during a spay could significantly increase the risk of ovarian cancer in dogs. All of this supports other evidence that early removal of the ovaries and uterus can prevent several serious types of cancer in animals and can also prevent serious infections of the uterus (pyometra).

It will be interesting to see if some of the blogs and veterinary newsletters that responded so enthusiastically to the ovaries and longevity paper also give attention to this new paper in JAVMA. I suspect that they won't, as this paper is not really very surprising, but it does relate (and contradict) to the paper about rottweilers they were so excited about a month or two ago.

Another version of the naturalistic fallacy in the quest for longevity.

2010-02-22T13:50:00.000-08:00

photo credit; national park service

It is not unusual for promoters of raw diets such as BARF and "natural" diets like the evolution diet to claim that wild animals are much longer lived than domestic animals, especially when they are fed commercial dry food. The culprits in kibble are variously claimed to be "diseased" animals, grains, or various preservatives or unnamed "toxins". Similar claims for longevity in wild animals in their natural habitats are often made by promoters of various types of "natural" medicine such as herbal and homeopathic remedies. These claims have always struck me as rather silly, so I thought it might be interesting to look at some longevity data for different species in the wild and in captivity, what they are fed in captivity, and how their longevity compares to closely related domestic animals. It might also be interesting to consider how humans and especially dogs have evolved together and how cooking and/or processing food has influenced that evolution.

It is sometimes difficult to evaluate the longevity of animals in the wild, but we do have excellent records of wild wolves in Yellowstone National Park since their reintroduction in 1995. The Yellowstone wolves have been closely monitored and studied for 15 years now, and we have data on hundreds of yellowstone wolves.
The 2008 Annual Report of the Yellowstone Wolf Project lists all known cases of mortality and the ages at mortality and the oldest surviving wolves in Yellowstone. Pup mortality has ranged from 0 to 71%, but seems to average about 50%. Periodic outbreaks of canine distemper virus seem to be responsible for years with higher pup mortality. For wolves that survive to adulthood, adults are considered "old" at greater then 5 years. At the time the 2008 report was written, wolf # 192M of the Belcher Pack was nearing 12 years of age and was the oldest known Yellowstone wolf. There were also at least two other notably old wolves alive at the time that were 11 years old. The average lifespan of a Yellow stone wolf is about 4 years. Longevity records for wolves in captivity indicate that wolves in captivity can live up to 20 years, and the oldest record in the wild is 16 years. Wild wolves die of intraspecific aggression (killed in conflict with other wolves), injuries, disease, and malnutrition. Wolves in captivity (and domestic dogs) do not tend to die of the same things-they live long enough to suffer from the diseases of old age-degenerative joint disease, cancer, etc. Wild wolves (with the exception of some endangered subspecies such as the Mexican wolf and the Red wolf) may have more genetic diversity than most domestic dogs as well, which may reduce the incidence of certain types of cancer in wolves compared to some inbred breeds of dogs independent of diet.

Since wolves in captivity live longer than wild wolves (and possibly longer than comparably sized domestic dogs) , what is the recommended diet for captive wolves? The husbandry chapters of the Nutrition Advisory Group of the American Zoo and Aquarium Association seem to recommend dry, commercial dog food as the primary source of food for captive wolves. (here, here, and here). There is also some evidence that the dental hygiene of captive wolves is better when fed commercial dry dog food then when fed a raw meat diet supplemented with bone meal and vitamin and mineral supplements. These recommendations indicate that professional zoologists and zoo veterinarians find commercial diets superior to raw meat diets for several reasons. Bones and whole prey may be given for behavioral enrichment, or to help transition wolves to predation in reintroduction projects, but ordinary dog food is perfectly adequate to maintain wolves in captivity and avoids problems associated with nutritional imbalances, bacterial contamination and spoilage.

The situation in cats is similar, although records for longevity for small cats (genus Felis) in the wild appear to be similar to the records for captivity. This may be because small cats tend to eat small prey that is not as likely to injure the predator and are not as subject to attack by neighboring cats . Average lifespans of cats in the wild are probably much lower than domestic cats due to disease, injury and starvation, despite the potential for small wild cats to live as long as their captive counterparts. Zoo standards for keeping small felines also indicate that commercial dry cat food is the preferred maintenance food in zoos, with whole prey reserved for behavioral enrichment purposes.

Finally, I would also like to address the idea that raw food is better because humans evolved eating raw food. While this is obviously true to a point,there are recent discoveries in Africa indicating use of controlled fire as early as 2 million years ago and the hypothesis that cooking made more types of food available and digestible to early human species and drastically influenced human social structure, reproduction and body size. As early humans (Homo erectus, neandertalensis and sapiens) spread out of Africa, their ability to do so and their success depended on cooking and the use of fire. It appears that dogs were domesticated much later, separating form wolves 15-30 thousand years ago. Part of this evolution probably involved wolves or early dogs scavenging waste and food scraps from trash heaps. The separation of dogs from wolves also seems to be related to the advent of agriculture, which means food surpluses in the form of grain and possibly root vegetables which need to be cooked or otherwise processed for digestion by humans and dogs. Cooked food may well have been important to both human and canine evolution and may have a lot to do with why we are human and dogs are not wolves in the first place.

The science behind human and animal nutrition, and the increasing knowledge of how cooking has influenced human evolution, first with cooking of wild foods, and later with the development of agriculture is fascinating. It stands in stark contrast to the vitalism and pseudoscience produced by the raw food supporters. Animal lifespans in the wild are generally much shorter than those of domestic or captive animals. While wild animals tend to die of injury, malnutrition or infectious disease before they get a chance to get cancer, there is no evidence that good quality commercial diets or cooked food cause disease in pets. The varying incidence of various cancers in different breeds would indicate again that many of the diseases which raw diets are supposed to prevent have a strong genetic component. Changes in kennel club breeding practices eliminating the severe inbreeding present in so many breeds is likely to benefit pet health more than a raw diet or a pseudoscientific "evolution diet" ever will. Claims that wild relatives of domestic animals live longer than the domesticated species do are demonstrably false, and the idea that raw food or some other type of "evolution" diet will extend lifespan appear groundless.

Purebred dogs and Disease. Veterinary responsibility?

2010-01-31T15:01:00.000-08:00

A couple of recent posts at Terrierman's Daily Dose makes some good points about the shared responsibility which the veterinary profession holds along with kennel clubs and dog breeders for the health problems that are all too common in many breeds, and are due to breeding (inbreeding) practices which result in horrendous problems directly related to the resulting anatomical and genetic train wrecks that define many purebred pets.
Terrierman's blog and website are worth a look for a perspective on working dogs and the few breed organizations which actively try to limit and/or discourage the type of inbreeding that is all too common, and perhaps nearly universal in kennel club "show" breeds.

The involvement of the AKC and prominent breeders with the AVMA and some veterinary schools is another area where scientific evidence is falling short in the world of veterinary medicine. Organized veterinary medicine has been strangely silent on the problems associated with the inbreeding of pedigreed dogs. Terrierman seems to have a valid point that financial interests (support of veterinary schools, the AVMA, providing pet insurance, etc) by kennel clubs is suppressing criticism of bad breeding practices by the veterinary profession as a whole.

I think that changing current breeding practices has the potential to improve pet health more than nearly anything other than the development of effective vaccinations did. Many common problems in purebred dogs and cats have dramatically different incidences in different breeds, suggesting strong genetic influences on these diseases. Scientific veterinary medicine can and should encourage kennel clubs to change current breeding practices which result in so many unhealthy dogs being sold to the public. It is also interesting that the AKC pet insurance automatically excludes "any congential/inherited condition" from coverage, while encouraging breeding practices which lead to exactly these problems.

Another interesting aspect of this subject which seems to tie into this topic is the promotion of unproven therapies (Complementary, Alternative and Integrative medicine) by many breeders and in some of the AKC publications. I wonder if the seeming affinity of kennel clubs for CAM is a little extra smoke and mirrors to distract people from the real causes of so many of the problems in purebred pets. These therapies are indeed often promoted in publications such as Veterinary Economics as a good way for veterinarians to increase their income. While I don't agree with Terrierman 100% on his recommendations on vaccination (he goes a bit farther than current evidence would indicate, but not by a whole lot) and a few of his other medical advice, I understand where he is coming from and that his recommendations are a response to many veterinarians who make decisions on vaccine frequency, parasite control, etc. based on what is best for their income, not necessarily what the evidence supports.

I think kennel-club endorsed breeding practices are indeed an area in which the science and evidence based veterinary community could make a difference in the lives of animals and the practice of veterinary medicine.

Ovaries and Longevity? A new study and a poor report.

2010-01-28T21:45:00.000-08:00

I received my copy of Veterinary Practice News today. It is the February issue, which is not yet available online, but one of the front page articles claims that a newly published study links increased longevity to dog's which retained their ovaries for at least 6 years. The actual study is available here. To be fair, Veterinary Practice News is not peer reviewed in any way, and is mostly an excuse to sell advertising. It is sent out for free to practicing veterinarians and is published in a tabloid format with articles of interest to veterinarians. The article in question is titled Study Links Ovaries and Longevity, and claims that their canine model compares well with humans in relation to longevity. The Skept Vet has an excellent summary of the benefits and risks of neutering (click through to download the PDF) which relates to this post, and helps to explain some of the problems I have with the article and the study.

the article itself is a typically hyperbolic report that suggests veterinarians should rethink their spay/neuter practices based on the results of this one study. Unfortunately, the paper draws nearly the same conclusions.
There are a couple of confounding factors which the authors claim to have accounted for, but may not have as well as they could have.

The main problem I have with the study is that it involves only one breed, and has relatively small sample sizes. The breed use for the study was Rottweilers, and the total sample size was 100 dogs of usual longevity and 83 of exceptional longevity. Rottweilers are a breed that has a high incidence of cancer, including osteosarcoma, the incidence of which may be strongly affected by the age at which a dog is spayed or neutered (see The Skept Vet summary linked above). Other cancers in rottweilers may also be affected by reproductive hormones in this way. Indeed, when all the dogs who died of cancer (73% of the usual longevity group and 32% of the exceptional longevity group) were removed from the study, the total sample sizes decreased to 27 and 53 respectively. with these small numbers, the authors still claim that retaining ovaries for six years or longer provided a protective effect.

It would appear that retaining ovaries may protect rottweilers from certain types of cancer that are very common in that breed, but it is not clear to me that simply keeping their ovaries was the only factor which resulted in increased longevity. The exceptional longevity group also averaged 5lbs lighter and a half an inch shorter than the usual group. This could reflect a protective effect of smaller size, or a difference in breeding which resulted in smaller size and also reduced susceptibility to certain diseases. The authors do not address these potential confounders, and present no data to suggest that the difference in size and weight could have been related to the age of spaying or genetic factors.

Before any claims such as those made in this paper, and especially in the Veterinary Practice News story are taken too seriously, they should be replicated in other breeds and larger populations. At the very least, the most common cancers and other causes of death are much different in rottweilers and humans. That alone should make the authors think the rottweiler model for human longevity may have some problems.

The Immortal Life of Henrietta Lacks

2010-01-19T16:15:00.000-08:00

For those interested science and a wide variety of issues ranging from the ethics of informed consent and the abuses of patients, especially minority patients which have resulted in some of the mistrust directed toward scientific medicine, this should be an excellent discussion. Rebecca Skloot's (go Colorado State!) new book will be available early in February, and is available now for pre-order. More information at Terra Sig.

Canine Distemper-a treatment?

2010-01-02T19:04:00.000-08:00

      Along with the Rabies outbreak Arizona has experienced this year, wild and domestic animals are also suffering from a Canine Distemper virus outbreak as well. I have seen several puppies with distemper this year, when I only saw three cases in the preceding decade.Canine distemper is very rare in domestic dogs because the vaccine is very effective. Several common types of wild animals-Canids (dogs, foxes, coyotes), Mustelids (skunks and weasels) and Procyonids (raccoons and coatis)-are susceptible to canine distemper and are capable of spreading it. This is a good reason for universal vaccination of dogs, as individual immunity is probably as important as herd immunity when a wild animal reservoir for disease exists. relying on other pet owners having their pets vaccinated ignores the potential of spread from wildlife. Distemper is an RNA virus related to measles, rinderpest, and of particular interest to this discussion, Newcastle virus. All of these viruses are Paramyxoviruses. In the process of treating one of these puppies with distemper, a client asked me about a treatment invented or discovered by a retired veterinarian named Dr. Alson Sears using Newcastle virus vaccine, and primarily promoted online (several websites and a facebook group) by someone named Ed Bond, who apparently has no medical or veterinary background, but who thinks his dog was cured by Dr. Sears' treatment. this treatment is not really "alternative", but it does illustrate how clients and veterinarians can be fooled into thinking something works without taking into account possible confounding factors. At least Dr. Sears and Mr. Bond seem to be sincere and do not seem to be making much if any money on this treatment.

     Like many viral infections, many factors including varying strains of virus, and multiple host variables affect the severity and course of the disease. Young puppies 3-6 months old are the most susceptible-younger puppies have some protection from maternal antibodies acquired through the placenta, and older dogs are both less susceptible to the virus and more likely to be immune to vaccination or mild infection. Effective vaccinations have been available since the 1960's, and I cannot find any data with specific information about mortality rates. Canine distemper does have a high mortality rate in puppies, probably much greater than 50%, and dogs that survive are likely to have severe neurological complications months or years later. However, depending on factors such as age and immune status, some dog do have mild cases, and some dogs do recover completely. These cases have the potential to convince clients and veterinarians that a variety of ineffective treatments work. It is natural for owners to bond with puppies quickly, and providing supportive care to a very sick puppy is tedious and frustrating, which leads people to look for other potential treatments for the disease.

     One client this year was in just this situation, and as I mentioned above, brought my attention to Dr. Sears' "treatment" for canine distemper. I will repeat that I have no reason to think that Dr. Sears or Ed Bond are not sincere and honest in their belief that this treatment, which involves either creating serum from a donor dog or treating the infected dog directly by injecting modified-live virus Newcastle vaccine (usually used for poultry) intravenously. They also encourage vaccination, and state that the vaccine is the best way to prevent distemper. Unfortunately some of the instructions they provide on their site seem to be directed more at owners or shelter personnel than to veterinarians. They posit that the newcastle vaccine virus is better than distemper virus at inducing cytokines (a non specific term for a wide variety of proteins such as interleukins, interferons and others) and these cytokines enable or "stimulate" the dog's immune system into fighting off the distemper infection. While this idea is not impossible, there are several things about the claims on the various websites that raise red flags for me. These include; 1: claims for effectiveness with absolutely no data presented to back up those claims, 2: hints that most dogs still experience the usual complications and sequelae of the disease, 3: a lack of information about side effects or mortality from the treatment or in the dogs used as serum donors, 4: the claim on the page about Dr. Sears that he has developed treatments for a wide variety of diseases but has never published anything about these treatments, 5: finally there are several reasons to be concerned about potential problems with this treatment that are not related to it's effectiveness or lack thereof.

     1; They claim that injecting the serum or vaccine early in the disease will cure distemper within 24-48 hours. However, they do not provide anything other than a few testimonials to support this claim. They say Dr. Sears has treated hundreds of dogs, but do not provide any well documented case reports. Apparently Dr. Sears first developed this treatment in 1970, and "presented" it at a veterinary conference, but was told to sit down. Since then, he has apparently kept the treatment to himself until Ed Bond started the various websites in about 2000. Dr. Sears says he does not have money to research the treatment, but he has not, as far as I can tell, even published any case reports. A case report basically only requires good records and some time to write it up. If the evidence from the case report is compelling enough, others may do the research needed to develop further evidence. Science and medicine progress by the publication and free spread of knowledge, not by keeping things secret for decades.

     2; Statements they make on their site recommend continuing supportive care during and after the treatment, which is generally all we can do to try to help a dog make it through the infection anyway.

"Even if the treatment is successful, the disease has probably done damage to the lungs, stomach, eyes, pads of the feet, etc. You will need to treat these symptoms as needed."

3; They claim that giving the patient or donor dogs the Newcastle vaccine creates a cytokine storm;

"The Newcastle Vaccine creates a thunderstorm of activity within the dog’s immune system. We think this unleashes a previously unknown class of cytokines — proteins that create an immune response — that can enter a cell infected with distemper and kill the virus. We don’t know how or why, but it works and it works quickly, often within 24 hours."

Cytokine storms are thought to be one of the reasons certain viruses are so deadly (the 1918 flu pandemic for example). If they really are creating a cytokine storm, then at least some of the donor dogs or patient dogs should be expected to show the effects of a cytokine storm, which can include respiratory failure and death. However, they say the procedure is safe and that they have never had a donor dog die.

4; Dr. Sears claims to have developed novel treatments for several other diseases, but has never published anything about those either. Some of these diseases either have other established treatments, are preventable, or are self limiting.

"Diseases that he has developed treatments for include distemper, herpes (fading puppy syndrome), feline FUS, post-surgical cutaneous granulosum of the doxy breed, giardia, canine and feline trichomonas, babesia gibsoni and others. However, none of this has entered the veterinary literature at this time."

Why have none of these wonderful treatments entered the veterinary literature. As I mentioned before, case reports are not expensive, and while scientific criticism can be harsh, that is how progress is made, if you have the evidence to back up your claims.

5; There are several reasons to be cautious with a treatment like this. Paramyxoviruses have a nasty habit of occasionally affecting different species than usual, and a search on PubMed for zoonotic paramyxoviruses
gets 19 hits, including one on the detection of antibodies to avian viruses in humans and another potentially linking Paget's disease to canine distemper virus exposure. There are also potential concerns about recombination of live-attenuated Newcastle vaccines with other viruses. While these concerns may seem slightly far fetched, they are no less plausible than the postulated treatment itself.
Finally, there is the concern that injecting a very sick animal with an attenuated vaccine could be dagerous to the individual patient. I wonder how many patients have died under this treatment protocol? they do say procrastination means death, but provide no information about how many animals have not survived the treatment, either due to it's inefficacy or to adverse effects.

Anytime someone makes claims such as the claims that are being made for this treatment, they have an obligation to keep good records of both the positive and negative outcomes. At this point there are hints that the treatment may not be as effective as it's supporters would like, but by focusing on the positive outcomes, and minimizing the negative, there is no way to tell if the treatment is effective, ineffective or just downright dangerous. This is true for this treatment as well as many CAM treatments. When some patients get better, it is easy to attribute their improvement to whatever you did, but some dog have always survived distemper.

Known unknowns and unknown unknowns in herbal veterinary medicine.

2009-12-13T12:34:00.000-08:00

I am afraid I can't resist stealing my title from Donald Rumsfeld, because I think it describes the problems of using herbal remedies in different species quite well. What are the risks of using herbal products in animals?

There are the known problems common to herbal treatments such as unknown and.or variable concentrations of active compounds in herbs from different sources and even from the same source but harvested at different times and under different conditions. Sometimes demand for herbs or other natural products can lead to damage or even extinction to rare species used in various healing traditions. There are many examples of contamination of herbal products, and some traditional remedies that may be represented as natural or herbal may be neither. When demand for a certain herbal product rises quickly (Such as the use of Chinese Astragalous for influenza viral infections) there may be a strong motivation to use different portions of the plant than usual or to substitute other related plants or to adulterate the product with something else to make up the volume.
These types of problems are common to many if not all herbal remedies sold and are what I consider known unknowns when dealing with these types of products in veterinary medicine.

When herbal products that may have been used traditionally for humans (it is fairly common for veterinarians to use Chinese herbal medicines on their patients) unknown unknowns come into play.
Often different species absorb and metabolize the same plant or drug very differently, and sometimes unexpected toxicities can arise in different species. Even in herbivores, different species can react differently to toxic plants, and one species may be able to consume a given plant safely, while another species may not.
Once you give a carnivorous animal (especially cats) herbs other problems arise. Cats have much lower levels of some liver enzymes such as glucuronosyltransferase(1) which converts toxic metabloites of drugs such as acetaminophen to less toxic compounds. One reason cats may have lower levels of such enzymes is that cats are obligate carnivores, and eat less plant material than other carnivores such as canines and bears, and probaly have less need to metabolize plant toxins.

Cat's red blood cells are also more sensitive than those of other species to oxidative damage, and small amounts of onion or garlic can cause Heinz body anemia in cats. when I was in veterinary school in the late 1980's, it was common to syringe or tube feed sick cats baby meats. Some baby meats have onion powder added for flavor, and there were cases of cats developing heinz body anemia after a few days of feeding baby meats containing onion powder. Now special diets are available for critically ill pets and this problem is not so common. Cats are also more sensitive than dogs to plant-based insecticides such as Pyrethrins and "natural" insecticides such as essential oils. Both dogs and cats have been poisoned by the use of pennyroyal oil, a popular substitute for flea and tick control products (2).

While some of these examples are well known and documented, I call this type of problem "unkown unkowns" because these issues are often unanticipated and are discovered when someone gives their pet a product and then discovers that the animal is not responding well. Other examples of this type of discovery include grape/raisin toxicity in dogs, and Lilly toxicosis in cats (3).

Because of the variable nature of herbal remedies and the potential for unknown and unforeseen toxicity, I think veterinarians and pet owners should be very cautious when using these types of products in animals. Unfortunately, the primary reference for veterinary herbal medicine, while giving lip service to these issues, also seems to put great value in untestable concepts such as Chinese and Ayurvedic forms of vitalism, and repeats standard CAM claims that natural products are always safer and less toxic than standardized pharmaceuticals. While they do state that essential oils should be avoided, they often state that many of these products "appear to be safe", without much consideration for the variables and unknowns I have discussed here. The book does not inspire confidence in me at least.

References;

Sellon, R.K. Acetaminophen, pp. 550-558 in Small Animal Toxicology, 2nd ed. 2006, Peterson and Talcott, eds, Elsevier/Saunders, St. Louis.
Poppenga, R.H. Hazards Associated with the Use of Herbal and Other Natural Products, pp. 312-344 in Small Animal Toxicology, 2nd ed. 2006, Peterson and Talcott, eds, Elsevier/Saunders, St. Louis.
Mason, J.A., Khan, S.A. and Gwaltney-Brant, S.M. Recently Recognized Animal Toxicants pp. 138-143 in Current Veterinary Therapy XIV, 2009, Bonagura and Twedt, eds.Elsevier/Saunders, St. Louis.

Ray Comfort edition of "Origin"

2009-11-18T14:22:00.000-08:00

A local church group was handing out free copies of The Origin of Species with a special introduction by "banana man" Ray Comfort. This introduction contains many fallacious arguments that have been refuted many times, such as the idea that Darwin is directly responsible for Adolf Hitler and the holocaust, and ideas that there are no transitional forms or "missing links" in the fossil record.

It is interesting to note that the announced date of distribution was the 19th, but apparently fears of handouts of information countering the introduction from the NCSE led them to bear false witness yet again and change the date. Unfortunately typical behavior from the young earth creationist crowd.

Music with a Skeptical theme.

2009-10-13T21:01:00.000-07:00

I am a fan of traditional and folk music, and just found a new album that I have been waiting for for several months. The Darwin Song Project was sponsored by the Shrewsbury folk festival for the Bicentennial of Darwin's birth. One of the singer-songwriters who participated was one of my favorites, Karine Polwart, from the Scottish Borders. Her song "We're All Leaving" is on the album. Karine's EP "Daisy" also has songs with scientific and skeptical themes. I was not familiar with some of the other artists from both the UK and the US, but I am impressed with the results of the one week retreat where the songs were written. If you enjoy traditional/folk music, this is an enjoyable album.

2009-10-11T19:00:00.000-07:00

Last week an interesting discussion occurred on VIN and spilled over onto The SkeptVet Blog. Coincidentally, NPR's Science Friday for October 9th was about veterinary medicine, and included some discussion of Stem Cell research. Dr. Lisa Fortier is an equine surgeon who is active in research in the areas of cartilage and tissue repair. She mentioned that there is still a lot of basic research that needs to be done to answer questions about what types or stem cells will be most effective for certain treatments, and to evaluate the safety and effectiveness of stem cell treatments. She also made a good comment in response to a question about Lyme Disease regarding the difficulty of diagnosis, and the fact that the antibiotics used to treat Lyme disease can have anti-inflammatory effects that can cause improvement in lame horses that may not have had lyme disease in the first place. I thought this comment demonstrated the problem of confusing correlation and causation quite well.

There was also a small animal veterinarian on the panel, Dr. Sarah Meixell from Veterinary Care of Ithaca. During the question and answer period, at about the 33minute point in the show, Dr. Meixell stated that acupuncture and Chiropractic were very effective treatments for animals, with no mention of any evidence to support the claim. Even worse, a minute or two later, someone asked about "organic" treatments and she said that there are Homeopathic vets who treat animals. When the show host Ira Flatow gently challenged this statement by saying that homeopathy might just keep the owner happy, she said "No it actually helps the pet".

I thought the show demonstrated the contrast between science and evidence-based veterinary medicine and alternative medicine in an interesting way. While the other veterinarians on the show seemed to be careful to emphasize science and evidence, Dr. Meixell boldly asserted that several CAM modalities, including homeopathy, were effective. She does not seem to practice CAM herself, at least from what I can see on the Veterinary Care of Ithaca website, but she appears to accept it's use uncritically, and gave many listeners the impression that it works.

This is exactly the type of situation that many veterinarians tend to find themselves in when trying to discuss CAM critically. If we challenge statements supporting modalities that are not supported by the evidence, we are accused of being rude, no matter how politely and discreetly the challenge. It was interesting to see the researcher involved in studying stem cells qualify her answers and explain what still needed to be discovered, while another vet seemed to accept several varieties of CAM uncritically.

More rabies information.

2009-09-21T16:40:00.000-07:00

Related to my last post is this paper on a current rabies epidemic in China, the result of low levels of rabies vaccination in dogs, and transport of infected dogs as food animals from one aea to another. Over the last 15 years the number of human rabies cases in China has risen from about 150 in 1996 to over 6000 in 2005. This is a dramatic demonstration of how effective vaccination, animal control and other public health efforts can be, and how severe the consequences are when such measures are neglected.

Rabies vaccine fears and relative risk.

2009-09-19T11:51:00.000-07:00

People are often not very good at assessing relative risks. This can be expressed as a fear of flying, even though the relative risk of dying in a car accident on the way to the airport is probably much higher than the risk of a commercial airline crash. Two papers published in the September 15th issue of JAVMA (Rabies surveillance in the United States during 2008, Blanton, et. al. and Rabies in vaccinated dogs and cats in the United States, 1997-2001, Murray, et. al.) and a post and discussion on Dolittler concerning these papers illustrates how the relative risk of side effects of a vaccine versus the risk of the disease and related consequences. The comments related to the post are particularly revealing, and I believe show how veterinarians and their clients sometimes approach an issue from different angles and can end up talking past each other, especially when a client may be mistaking the relative risks involved.

So what are the risks of vaccination versus the risk of disease as illustrated by these two papers and the discussion on Dolittler?

Risks related to vaccination mostly involve adverse effects of vaccination. Adverse effects include allergic reactions, delayed reactions such as granulomas at the injection site and then the well-known and well-publicized vaccine associated sarcomas which occur mostly in cats, but can happen very rarely in dogs.
Most of these adverse effects are treatable and/or preventable (allergic reactions) and may happen a few times in 1,000 vaccinations. More serious life threatening reactions to vaccines are very rare, and many vets may see very few in their career. Vaccine associated sarcomas in cats may happen in one in 1000 cat to 1 in 10,000 cats over their lifetimes, depending on which study you would like to read. These sarcomas can be very difficult to remove depending on the location they form in, and can be caused by inflammation not related to vaccination. There are newer vaccines for cats that do not have the adjuvants suspected of causing sarcomas to form.
Some other serious diseases and problems such as generalized allergies, autoimmune diseases and "vaccinosis" (a general term for ill health blamed on vaccines that does not have any real meaning or definition) have never been clearly linked to vaccines and are probably not directly or specifically caused by vaccines.

What is the risk of any given pet being exposed to Rabies? This risk may be higher than most people think. The first Rabies surveillance paper shows that Rabies exists in wildlife in every state except Hawaii, and that various bat strains are the most widespread type. There are also regional variations-Raccoon rabies along the east coast, several skunk variants in the midwest, southwest and California, and fox variants in the southwest. A new strain of bat rabies has recently made the jump to skunks and foxes in Arizona. Canine rabies strains have been eradicated in the U.S. due to vaccination and animal control efforts, so all cases of rabies in domestic animals come from wildlife. Any animal that goes outside at all is at risk of being exposed to rabies. Since bat rabies is so widespread, it is possible for a pet to be exposed anywhere bats occur. Rabid bats have an annoying habit of turning up in strange places, including inside homes, so keeping cats indoors is no guarantee that they will never be exposed.

Another risk of having a pet that is not vaccinated against rabies or that is not current on rabies boosters is what could happen if the pet happens to bite someone or is exposed to a rabid animal.
Animal bites treated by doctors legally have to be reported to local health departments, so that appropriate follow up and rabies preventative treatment can be done in a timely manner. In the second JAVMA paper, reports from 20 states on dogs and cats tested for rabies between 1997 and 2001 are listed. There is no way to test a live animal for rabies infection, so all of these animals were euthanised because of a bite or died of neurologic disease that raised a suspicion of rabies. During that period these stated tested 78,669 dogs and 92,318 cats for rabies. 248 dogs (0.32%) and 685 cats (0.74%) tested positive. many of these animals may have been strays, but some of them were pets that were not vaccinated. 13 dogs and 22 cats had a history of rabies vaccination, but only 2 dogs and 3 cats were classified as currently vaccinated. As with any vaccine, failures can happen, but are very rare. This also indicates that one vaccine or an extended schedule of rabies booster does increase the risk for rabies infection.
If an unvaccinated pet bites someone, the local health department can have the pet euthanised and tested for rabies if they think they need to. This is a risk to the pet that is unrelated to the actual risk of rabies infection, as shown by this study-over 99% of dogs and cats tested for rabies were negative. Other states undoubtedly tested many animals as well, but did not agree to participate in this paper, so these numbers are probably even more dramatic across the entire country.

Some of the comments on Dollittler were common arguments many veterinarians hear. "My cats never go outside, they are always in the yard, etc." These papers show that rabies is common and widespread in wildlife, and that hundreds of unvaccinated and even a few vaccinated pets do get rabies, and tens of thousands of unvaccinated pets were killed for rabies testing over a five year period. This is the perspective veterinarians are coming from when they recommend rabies vaccines. The risk to pets and humans from rabies is real and the consequences of infection are severe. Some people who do not want to vaccinate their pets consider information like this fear-mongering, but failing to inform pet owners of these risks, along with a discussion of the rare but serious side effects of vaccines would constitute negligence on the veterinarians part.
Failing to keep a pet current on it's rabies vaccination can result in the death of the pet even if it does not get rabies. This is a result of the need to ensure that humans receive appropriate treatment in a timely manner when exposed to a potentially rabid animal and is a risk that most pet owners are not aware of. Just because a client thinks their pet will never bite anyone or will never get outside, does not mean that it will never happen. It does not mean that your vet thinks you are lying, but we understand the relative risks of vaccinating versus not vaccinating in a way that the pet owner may not.

Mushroom extracts for cancer?

2009-08-16T20:25:00.000-07:00

A recent question from a client about mushroom extracts for "immune modulation" in cancer patients led me to look into the evidence for these supplements. While the idea that mushrooms could contain medically effective compounds is reasonable, (there are many active chemical compounds, including some very toxic compounds) the evidence for their use is still weak. There have been traditional uses of mushrooms in cancer treatment for centuries or longer, and preliminary testing of mushrooms and compounds in mushrooms since at least the late 1970's. As is the case with many things which fall under the DSHEA as nutritional supplements, mushroom extracts are not required to be tested for efficacy or safety before being sold.

This website is the one my client was asking about. They claim that their two supplements, K9 Immunity and K9 Transfer Factor will help to modulate the immune system which will help to prevent cancer and also help the immune system to recognize the cancer and eliminate it if it is already present. They really have no data to support these claims, and so resort to vague, nonspecific claims of "immune modulation", "detoxification" and "support". One of the videos they have produced looks like a news feature, but is really the president of the company promoting the products. He is careful in that video to avoid specific claims, and says repeatedly that pet owners should pursue appropriate treatment, but their supplements can "improve quality of life". All of the testimonials indicate that the dogs that have done well received appropriate treatment for their cancer including surgery, radiation and/or chemotherapy.
There is never any evidence presented that using the supplements changed the outcome or course of therapy for any of these pets. A paper presented on the website as evidence of effectiveness is basically a series of uncontrolled, unblinded case reports with no controls for
comparison of outcomes, and does not really address the main claims of "immune modulation"
made by the site. Some of the dogs in the report died of their disease, some needed adjustments to their treatment due to side effects, (including immune suppression) and others had progression of their disease. Their definition of cancer as a failure of the immune system to recognize aberrant cells is very simplistic, and does not account for the complexities of cancer biology.

The website seems to be named to attract people searching for information about canine cancer, and has a discussion forum and pages giving basic information about four of the most common types of cancer in dogs, but every page and nearly every paragraph leads to a link or button to order their products. As with many unproven and untested products, the people who seem to be providing such sympathetic and valuable information are really just pushing their specific products. The cost of their two supplements would be between $240 and $300 per month for a giant breed dog (120lbs). That seems like a lot to spend for an unproven and probably ineffective treatment. If they are going to support research, they could at least do a randomized, controlled trail rather than a poorly done case series.

Supplements; the sales call.

2009-08-05T20:23:00.000-07:00

Yesterday the sales rep from our major supplier of veterinary supplies and drugs stopped by with a rep from a supplement company in tow. Since it was a hot day, and no one in Flagstaff has air conditioning, we decided to sit at the table out back under an awning (this will be important later). The supplement rep (SR for the rest of this post) was very nice, and is a sales rep, not a veterinarian or scientist-she was just doing her job. I did find the methods and claims she used interesting however. Because of DSHEA, supplement makers are not required to test their products for safety or efficacy and also cannot make specific claims to diagnose or treat disease.

The first type of supplement the SR talked about was a joint support supplement containing mostly Glucosamine and MSM. The company has scientific evidence to support their claims for this product. After the sales reps left, I had time to examine these claims more closely. Two of the studies they cite are in vitro studies, shich are fine, but say noting about actual clinical effectiveness, and the third looks better as it involves a randomized, blinded study that used force plate analysis and evaluation of inflamatory factors in the synovial fluid. The problem with this study is that only a summary written by the company is available, the actual paper has not been published, so there is no way to evaluate the methods and data they used.

Next came liver support supplements. My baloney detectors were activated when the SR said that it was "completely natural, and safe, with absolutely no side effects." Apparently it can also help to "detoxify" the liver. the references for the flier on this product have a lot of studies of the pathophysiology of various liver diseases, mostly in humans, and very little or nothing on the acutal clinical effectiveness of most of the ingredients.

Most of the information provided on this company's products was written by Susan Wynn, DVM, who the sales rep said was from the University of Georgia's College of Veterinary Medicine. Actually, Dr. Wynn is the past president of The American Holistic Veterinary Medical Association, and is an adjunct (generally nonsalaried and paid per class or lecture given) professor at Georgia. She is probably paid much better by this supplement company than she is for whatever talks or classes she gives at the veterinary school. She does not have any scientific publications that I could find (there is one case report of treatment of gastrointestinal problems with herbs) and she is the author of a book on veterinary herbal medicine. No controlled trials, but lots of dicussion of the "energetics" of different herbs-yet another type of energy medicine that I was not previously aware of.

Finally, at the end of the visit, the SR said something that I was hard pressed not to laugh at.
She looked around at the backyard, which I have spent the last 10 years making as pleasant as possible (rebuilding the patio, installing a pond and vegetable garden, planting trees, etc) and said; "you have really good feng-shuei here". Feng-shuei was one thing I never considered while improving the backyard. That comment mae me think that maybe the SR was not just doing her job as trained by the company, and maybe was more of a true believer than I thought.

Apparently this sales pitch works on many veterianrians, natualistic fallacies, vague references to toxins and all. It did not inspire me to start selling any of these supplements however.

Cognitive Dissonance

2009-07-24T20:22:00.000-07:00

Recent discussions on the alternative veterinary medicine e-mail list and on Pet Connection have made me think more about Cognitive Dissonance and the other ways humans can deceive themselves. Prometheus at Photon in the Darkness coincidentally has an excellent post up about cognitive dissonance today.

Unfortunately, Narda Robinson seems to be an excellent example of cognitive dissonance as well. For those of you who are not familiar with Dr. Robinson, she is the Director of Colorado State University's Center for Integrative Pain Medicine. While she seems to be very skeptical and science based in her analysis of many alternative modalities such as homeopathy, herbal medicine, and others, she often credulously endorses Reiki and possibly therapeutic touch, and teaches a $4,400 dollar course in acupuncture at CSU. She has studied the "neuroanatomical" approach to acupucture for many years. There is no doubt that sticking needles into living bodies causes a reaction in the nervous system. This reaction seems to include an effect on nerve transmission and can cause the release of endorphins in the central nervous system. The question is, does this have any significant clinical effect? Increasingly, the answer seems to be no.
Detailed and well-referenced discussions of the scientific evidence for the efficacy of acupunture are available here, and here. The acupucture archive at Science-Based Medicine is well worth a look as well. In short, the development of sham acupucnture procedures such as placing needles in random points, the use of fake needles that do not puncture the skin but appear to and tricking patients into thinking they are being needled by using things like toothpicks to create an illusion of being needled all seem to be as effective as "real" acupucture. This would indicate that the act of inserting needles has a potent psycological effect that can induce a placebo efect in humans, and possibly animals as well. (My previous post discussing the placebo effect in animals and their owners shows how thismight happen.) People often like to do something, indeed anything to help alleviate their animal's suffering. Unforunately, using an inefective or minimally effective treatment may convince the owner and veterinarian that they are helping, but the animal may still be suffering.
This is my foremost concern with the promotion of veterinary acupuncture. It is quite common for the proponents of veterinary acupuncture to claim that acupucture can reduce the need for anesthetic drugs, or help with postoperative pain and chronic pain. This may result in the use of inadequate doses of other, effective analgesic drugs and techniques. Veterinary pain relief has come a long way in the past few decades, and acupuncture to me seems to be a step backward rather than an improvement.
The reason I think that Dr. Robinson is an excellent example of cognitive dissonance is because she tries to force unscientific isdeas into her inconsistent idea of what the evidence shows. A true scientist and skeptic will put all their ideas, no matter how treasured, to the test of the evidence. While acupuncture is more plausible than homeopathy, the results of the best trials do not show much effect. Dr. Robinson and CSU are making a lot of money from their courses in acupucture and from treating pets with acupucture and other therapies with weak evidence. It is their responsibility to produce good evidence or effectiveness or to stop deluding themselves and others.
M

Orac's Friday dose of woo.

2009-07-24T08:11:00.000-07:00

Orac has his Friday dose of woo up and it is about veterinary medicine this week. A good example of woo, which unfortunately is all too often practiced by licensed veterinarians due to the nature of veterinary practice acts in the US and UK at least.

"Not testable by science"

2009-07-20T19:54:00.000-07:00

It is very common for practitioners of many "alternative" healing modalities to claim that the energy, vibrations, or "auras" they manipulate cannot be detected by modern science. Statements like this show a depressingly weak understanding of what we already know and what we are capable of measuring. The electromagnetic spectrum has been well known for over a century, and there are not any gaps in our understanding of it (there is no room for new unknown wavelengths or particles in the range of energy that exists in living bodies). We know in great detail how nerves, muscles and other tissues create and utilize energy, both chemical and electric and are continuously learning more details, none of which suggest any new, unknown mysterious force.
Our ability to measure incredibly small amounts of electromagnetic energy has also improved past the point that the discovery of some new unknown energy or vibration having a physiologic effect is vanishingly small. We can detect light and other wavelengths that have traveled for billions of years across the universe. We can also detect the light emitted by chemical reactions in human bodies. To get these types of images requires cameras that can detect light one photon at a time. Very weak signals in all other wavelengths (radio through gamma) can also be detected.
This understanding of the electromagnetic spectrum combined with extremely sensitive detectors makes the likelihood of discovering some new type of energy affecting bodies vanishingly small. Claims by CAM practitioners that science cannot measure what they do reflect either a profound ignorance on their part or a criminal disdain for the intellect of their customers.
An interesting exercise when confronting quacks is to ask how whatever they do works. If you get vague answers, keep asking questions. Often you will find that their ultimate answer is that it cannot be measured by science. This is a strong indication that their claims are unsupported by the evidence, and are not worth risking your money or your health (or your animals health).

The problem of Prior Probability, or why controlled trials of improbable propositions are a waste of time and money.

2009-07-13T22:06:00.000-07:00

A common criticism aimed by supporters of alternative medicine modalities at those who are skeptical is that we are closed-minded and intolerant. "It can't hurt to study homeopathy, acupuncture, etc. We might find out that it actually works!" There are many studies that show that many types of CAM are at least mildly effective, but I would like to suggest that there are good reasons why a mild effect might show up in research, and why skeptics do not accept these types of results.

Some of the reasons a treatment may seem to work include the placebo effect as discussed previously, selection and observation bias, and unfortunately outright deception (this can be unintentional). This can result in studies being published that appear to show an effect. Often negative studies are not published at all (publication bias) as researchers and institutions often do not like to publish negative studies. Since the evidence-based medicine movement considers controlled trials the gold standard, reviews of CAM research can show potential mild effects or a need for further research that do not really exist. The prior probability of the modality may not be considered at all.

What is prior probability? It is simply defined as the scientific basis for something. CAM modalities such as Homeopathy, Reiki, Therapeutic Touch and other forms of "energy medicine" have extremely low prior probabilities because they either defy all known principles of physics, chemistry and biology (homeopathy) or are based on "energies" which no one can measure or demonstrate the existence of. Other types of CAM such as herbal medicine may have higher prior probabilities because they actually contain measurable amounts of chemicals that may or may not have an effect. This concept of prior probability is why skeptics say that extraordinary claims require extraoridnary evidence. An idea of how this applies can be gained from an understanding of Bayes theorem, which uses prior probability to evaluate the likelihood that a hypothesis may be true. Bayes theorem can be used in place of p-values (which can be misleading because they may not have a sound theoretical foundation). Kimball Atwood gave an excellent overview of these ideas at the Science-Based Medicine conferece jsut before TAM7 last week. His bibliography is here. This bibliography contains much more detailed discussions of these concepts than I have presented here.

A good understanding of basic statistics and of Bayes Theorem demonstrates why extraordinary evidence is required to prov extraordinary claims. When the plausibility and/or probability of a claim is exceedingly low, weak evidence is not sufficient to prove that it is true or even suficcient to justify spending further resources researching it.

The Placebo Effect in Animals, and Their Owners.

2009-07-04T20:46:00.000-07:00

A common reason people give as "proof" that various questionable therapies work is that "animals do not get placebo effects, because they don't know they are supposed to feel better".
This seems to make sense-animals do not "know" that a given treatment is supposed to do something, and I have been known to say this myself in years past. However, there are several reasons why this view may not be accurate.
One reason is conditioned responses, otherwise known as a Pavlovian response. Animals learn to respond in certain ways to actions or treatments. This response becomes automatic or subconscious. Humans are susceptible to conditioned responses just as animals are, and a conditioned response may affect our expectations or the way we perceive a given situation.
It does take time for a conditioned response to develop, but it may happen fairly quickly, sometimes over the course of a few treatments. When combined with effective treatments, regression to the mean and/or the normal healing process, the effect can seem dramatic. We (both owners and veterinarians) have a tendency to think that what we are doing is helpful because we want it to be helpful. This is a normal part of human nature, and is why randomized, blinded and controlled trials have been devised to help eliminate sources of error and bias, and why such trials are considered stronger, more reliable evidence than case reports, anecdotes, and unblinded, uncontrolled trials.
Another thing that has been demonstrated to affect both animals and humans is expectation.
It is not unusual for dogs to be more active and lively even after a simple, quick treatment like a vaccination. The dog has learned that a trip to the vet involves a brief, mildly unpleasant episode, then often a treat or car ride that the dog enjoys. The same expectation on the human owner's or veterinarian's part of improvement can also affect the way we perceive how a treatment is working.
What is the evidence that this expectation on the part of a caregiver can create a "placebo effect" in the caregiver as well as the patient? There have not really been any studies done in the veterinary field, but a some studies of preconceptions held by parents demonstrate how such an expectation may affect how caregivers can be affected by treatments. This report discusses how the common perception that sugar or other foods cause hyperactivity in young children is unfounded, and a recent review shows how parents, teachers and medical personnel can be effected by knowledge and expectation of treatment. I have seen several clients give their pets rescue remedy, a bach flower remedy which is a type of homeopathic remedy to their pets to help with anxiety just before a visit. I have always thought that the remedy seemed to calm the owner down more than the pet, and these reports help to explain why that may be.
A reasonable understanding of these effects on caregivers should instill some humility in any caregiver, and a critical analysis of how effective any treatment is. Unfortunately, such humility and critical analysis seems to be nearly entirely absent in many practitioners of alternative treatments and often in conventional practitioners as well. The difference between the effective treatments that have been developed over the last century or so and ineffective alternatives is testing and analysis by the scientific method. If someone claims that a treatment is not testable by science, or that science cannot detect the effect, that should be a red flag that the claim that the treatment works is bogus.

Spread of bat-variant rabies virus in other species.

2009-05-07T19:39:00.000-07:00

I started to hear rumors about rabies virus spreading through the air from clients today. Then I got an e-mail referencing this article from National Geographic today. Apparently the article is the source of the rumors. There are a couple of problems with the article that make it difficult for people unfamiliar with the science involved to interpret.
First, calling this a new rabies virus in the title makes people think that the current outbreak of Rabies in foxes and a few skunks in the Flagstaff area might be something new and different.
The Rabies outbreak in foxes is a bat variant rabies virus that has crossed into other species several times in the last decade in the Flagstaff area. The thing that is different about these outbreaks is that the virus seems to be better at spreading in a new species of animals than bat variants usually are.
Rabies virus has many different genetic variants that are adapted to different species. All of these variants are capable of infecting other species, and basically all mammals are susceptible to infection with rabies. Often, when an animal or human is infected with a variant of rabies from another species, the new host is considered a "dead end" because the disease is fairly rapidly fatal after the virus reaches the central nervous system and the new host may not spread the virus very efficiently. When a host is infected with a variant of rabies that is adapted to that host, it is more likely to spread to another animal. The primary mechanism of spread is by bites or scratches that are exposed to saliva from the infected animal. On rare occasions the virus can spread by oral or nasal inoculation as well. This still requires close contact with the saliva or tissues, especially nervous tissue or salivary glands of an infected animal. There are several different places around the country with different variants of rabies in their respective species.
The CDC publishes annual reports on rabies epidemiology which list the number of animals tested positive for rabies and the human cases along with the variants that caused the disease in humans. This shows that Rabies is a common disease in wild mammals, and it is not unusual for it to be spread from one species to another. It is less usual for the virus to mutate and then spread widely in the new species. Apparently the outbreaks of bat variant rabies in foxes, skunks and bobcats in Northern Arizona over the past decade is the first time that humans have observed the mutation of the virus and its spread in a new species. This has obviously happened many times in the past, hence all the different rabies variants in many different species. It is even possible that bats are the initial reservoir for all rabies viruses and occasional mutations in the virus result in new variants that are better adapted to other species of mammals.
This paper documents the original outbreak of the bat variant rabies in skunks in Flagstaff in 2001. The current outbreak in foxes is also a bat variant, and is probably the same or a similar variant as the previous outbreaks were.
The main problems I have with the National Geographic article are the author's assertion that skunks described in the paper by Leslie, et. al. were spreading the virus "passively" whatever that means. Some people in the Flagstaff area have already interpreted this to mean that rabies is being spread as an airborne virus. It is spreading in a new species, but there is no reason to suspect that the virus is not spreading through bites or very close contact just like Rabies has always spread. The other problem I have is the quote from Barbara Worgess, the head of the Coconino County Health Department that "It shouldn't be able to spread from skunk to skunk."
There is no reason that the virus cannot spread from animal to animal, it is just unusual and does create a concern for the Health Department. Unfortunately Ms Worgess seems to say things like this to the media which make it look like she really does not know what is going on.
Fortunately, this new variant of the Rabies virus can be prevented by the same Rabies vaccinations that have been available for years. The fact that bats are often carriers of Rabies is an excellent reason to keep your pets vaccinations (including cats!) up to date, and the spread of the virus in a new species is a good reason to be cautious in the woods and around any wild animal that is acting sick or agressive. People that have been exposed to Rabid foxes in the Flagstaff area have been effectively treated with standard protocols just like other exposures to other rabies variants. Any time someone has been bitten by a wild animal or exposed to a bat (bat bites can be very hard to identify due to their small size) they should seek medical attention immediately. Rabies antisera and vaccinations do not work once symptoms appear.
The Natonal Geographic article is another example of the media publishing an overly sensational, inaccurate story. No one should panic, but should take sensible precautions.

Homemade and raw pet food diets-NOT safer.

2009-04-20T19:48:00.000-07:00

Homemade and raw pet diets have gained in popularity over the last year or two, especially after the boost they gained with the melamine contamination problems in many commercial pet foods.
Raw diets for dogs and cats often use meat and organs from commercial sources and can contain harmful bacteria such as Salmonella, Campylobacter, E. Coli and Klebsiella among others. Some raw diets contain whole bones or large pieces of bone that can break teeth or cause intestinal obstruction.
A paper published last week in JAVMA last week illustrates another potential problem with this type of diet. There are several suppliers of diet mixes that are designed to be mixed with raw or cooked ingredients by the owner and then fed to the pet. Most claim to be complete diets appropiate for feeding to puppies and adult dogs, or kittens and cats.
In this case at least, the diet was profoundly insufficient in minerals and vitamins and nearly killed the puppy. The dog recovered after several months on commercial dog food. Diets should be tested and approved by the Association of American Feed Control Officials (AAFCO). Food with this approval should have the appropriate levels of nutrients for the life stage of the pet you are feeding.
The abstract of the paper is quoted below as it requires a subscription to view;

Diffuse osteopenia and myelopathy in a puppy
fed a diet composed of an organic premix
and raw ground beef
Mark B. Taylor, ma, dvm; David A. Geiger, dvm;
Korinn E. Saker, dvm, phd, dacvn; Martha M. Larson, dvm, ms, dacvr
Case Description—An 8-month-old Shetland Sheepdog was evaluated because of the
sudden onset of signs of neck pain, collapse, and inability to rise. A cursory diet history
indicated that the dog had been fed a raw meat–based diet.
Clinical Findings—Initial evaluation of the dog revealed small physical stature, thin body
condition, and signs of cranial cervical myelopathy. Radiographically, diffuse osteopenia of
all skeletal regions was identified; polyostotic deformities associated with fracture remodeling
were observed in weight-bearing bones, along with an apparent floating dental arcade.
Hypocalcemia and hypophosphatemia were detected via serum biochemical analyses. The
dog’s diet was imbalanced in macronutrients and macrominerals.
Treatment and Outcome—The dog received supportive care and treatment of medical
complications; neurologic abnormalities improved rapidly without intervention. Dietary
changes were implemented during hospitalization, and a long-term feeding regimen was
established. Following discharge from the hospital, exercise restriction was continued at
home. Serial follow-up evaluations, including quantitative bone density measurements, revealed
that dietary changes were effective. After 7 months, the dog was clinically normal.
Clinical Relevance—In the dog of this report, vitamin D–dependent rickets type I and suspected
nutritional secondary hyperparathyroidism developed following intake of a nutritionally incomplete
and unbalanced diet. The raw meat–based, home-prepared diet fed to the dog was not feedtrial
tested for any life stage by the Association of American Feed Control Officials, and its gross
nutrient imbalance induced severe metabolic, orthopedic, and neurologic abnormalities. Inadvertent
malnutrition can be avoided through proper diet assessment and by matching nutrient profiles with
patients’ nutritional needs. (J Am Vet Med Assoc 2009;234:1041–1048)

Another reason not to use the Argument from Antiquity

2009-04-19T19:42:00.000-07:00

The Argument from Antiquity is a logical fallacy that is used very commonly in support of various types of alternative medicine. The fact that a particular treatment has been used for hundreds or thousands of years says nothing about the efficacy or safety of that treatment. Treatments used before scientific understanding of biology and medicine were invented by trial and error at best and were often based on profound ignorance or misunderstanding of the processes involved. At the time they were invented, all medicine veterinary or human, was in the same category. Some of the treatments used for many years were dangerous and harmful (bleeding, treatment with toxic heavy metals, etc.). Some treatments are "safe" and cause no toxicity or side effects because they have no effect at all. Some of these treatments may have survived for exactly this reason-they were safer than some treatments simply because they had no effect other than a placebo effect.
A recent paper provides another reason to be skeptical of traditional treatments. In this paper, the authors have developed a mathematical model to show how medical treatments can spread in populations. They included variables for the efficacy of the treatment, conversion and abandonment rates for the treatment, death rate due to the disease, and other variables. When they ran the calculations, they found that ineffective treatments were often more culturally fit than effective treatments. The main reason for this is that an ineffective treatment is often demonstrated more frequently than an effective treatment. This results in a larger number of people adopting the treatment, even if many of them later abandon it. In many cases the recruitment rate was much greater for ineffective treatments and the ineffective treatments had a greater cultural fitness than effective treatments.
This model is very interesting in that it shows how ineffective treatments can develop and persist in a population often better than effective treatments do. This is not earthshaking news to skeptics, and the model does not take into account other factors such as tradition or religious ideas that can also help ineffective treatments to survive. Herbal medicines are one of the most plausible traditional medical treatments, and some traditional herbs have been developed into modern medicines (aspirin is a good example). This model shows why even plausible treatments such as traditional herbs need to be evaluated scientifically before being accepted as an effective treatment. People are likely to favor ineffective treatments. The authors were able to apply their model to both human and veterinary treatments, and even self treatment by non-human primates.

2009-04-08T20:29:00.000-07:00

I saw this press release today about genistein, a compound found in soy that has been promoted as a supplement that can prevent and treat cancer. A couple of red flags came up for me in the press release such as this;

The researchers found that a commercially available form of genistein called GCP was effective in killing canine lymphoid cells in a laboratory setting, and that GCP is "bioavailable" in canines - meaning it is absorbed into the bloodstream where it can affect cancer cells in the body. The researchers hope that their findings will lead to the use of GCP for their canine patients in conjunction with traditional cancer treatments like chemotherapy.

This by itself sounds OK, but it does not mean that the concentrations of the compound which killed the cancer cells in vitro are safe or even achievable in dogs or humans. Then comes a claim that humans use genistein as a complementary cancer therapy;

"Humans have been using soy in conjunction with traditional chemotherapy for some time as a chemo potentiator," Suter says. "This means that the GCP makes the chemotherapy work more efficiently and faster, which translates to less stress on the patient and less money spent on chemotherapy."

That is a huge leap from killing cells in a petri dish, and is not substantiated by much evidence. Indeed Genistein is know to have estrogenic effects and may actually make certain types of cancer, especially breast cancer grow more quickly.

Finally the biggest red flag in the entire press release was the last paragraph;

"Since GCP is a dietary supplement, it is harmless to patients," he adds. "Plus it's inexpensive and easy to administer in a pill form. There's really no downside here."

A product such as this is not harmless to patients, and saying so could be dangerous to patients, human or animal, who have estrogen responsive tumors. There most definitely is a downside. They have also not established any toxic effects in living animals or humans of the concentrations required to kill canine lymphoma cells.

The paper this press release is referring to was published in the February 15, 2009 issue of Clinical Cancer Research. This paper is a report of a preliminary study of Genistein that was evaluating it's effect on one specific cell type, and they were unable to achieve high enough concentrations in dogs in a 72-hour dose escalation study. The study showed a potential effect for the compound for certain cancers, but there is still a long way to go before the correct dosage is identified and genestein is proven to be a safe and effective treatment. The author's conclusions were much more modest and reasonable than the press release indicated;

The results of these studies support the notion that canine high-grade B-cell lymphoma may represent a relevant large animal model of human non-Hodgkin's lymphoma to investigate the utility of GCP in chemopreventive and/or treatment strategies that may serve as a prelude to human clinical lymphoma trials.

The press release is misleading and could be dangerous if people read it and decide that this over-the-counter product is completely safe and useful for treating or preventing any type of cancer. This is an excellent example of why dietary supplements should be regulated similarly to drugs, and not declared "harmless".

Hot Chicks

2009-04-07T20:17:00.000-07:00

New Americauna chicks to keep our backyard flock going. These will lay green-shelled eggs starting in 6 months or so. They will also keep our grasshoppers and dandelions under control this summer.

What is CAM?

2009-04-04T23:06:00.000-07:00

Complementary, Alternative, or Integrative medicine (human or veterinary) is not one particular modality or treatment. There are many treatment methods which fall under these classifications.
Ideally, there is only medicine which has been shown to be effective scientifically, and that which has not. Veterinarians tend to use more treatments that have not been proven effective by well controlled clinical trials than are used in human medicine for a variety of reasons. These reasons include research limitations-there is much less money for veterinary medical research than for human medical research-the wide variety of different species veterinarians treat, and the financial limitations of animal owners. Since veterinary critics of alternative medicine are often criticized for using treatments that are not completely proven while attacking other unproven therapies, I will define complementary, alternative or integrative medicine as treatments that may require drastic changes in what is known about science to even work (improbable or impossible mechanism of action), treatments that may possibly have an effect but have not ever been tested or shown to be effective, and treatments that may have been proven, but are often co-opted by unscrupulous practitioners to either give themselves more credibility or take the treatment and exaggerate or twist it into something which is different than it was.
Of course, there is a wide spectrum of alternative therapies which range from completely ridiculous and improbable treatments such as homeopathy or therapeutic touch, treatments like acupuncture or chiropractic which might possibly have a physiologic effect but have still not been proven, to things like physical therapy, nutrition, exercise and vitamin supplementation that are part of any 'definition of medicine but are often claimed or abused by "alternative" practitioners. Some red flags for unproven therapies can include claims that the effect cannot be measured by scientific methods, large amounts of testimonials and/or anecdotal evidence, appeals to antiquity ("acupuncture has been used for 3000 years") claims that the treatment can only be explained by quantum mechanics, or claims that their treatment is being suppressed by some sort of conspiracy by big pharma and organized medicine.
Some of the people who practice these types of unproven treatments honestly believe that they work, and some are just out to make as much money as possible from gullible patients. In either case, it is unethical for a veterinarian and unfair to our patients to subject them to treatments that probably or definitely do not work. It is equally unethical to charge for such services and to encourage delusions that the pet is benefiting from them. Sometimes such delusions can lead to great harm and unnecessary suffering. Since veterinary patients are not able to choose for themselves, veterinarians have an added responsibility to advocate for their patients and to discourage treatments that are unproven, ineffective and potentially harmful.

Introductory post

2009-04-02T20:50:00.000-07:00

When I graduated from veterinary school nearly 20 years ago, there was no "training" in alternative medicine for veterinary students. Very few licensed veterinarians practiced things such as acupuncture, herbal medicine, therapeutic touch or chiropractic. In the time since I graduated, many veterinarians have "integrated" some of these modalities into their practices, with at least the silent acquiescence of their state veterinary boards. This blog is intended to examine alternative practices in veterinary medicine and the evidence (or lack of evidence) for them.
There may be occasional rants and there will be posts on other topics such as vaccinations in veterinary medicine and the sometimes bizarre claims made about them, interesting occurrences in biology, cryptozoology and the conflict between faith and science and evidence.

I hope you enjoy the ride.