Sunday, May 30, 2010

Acupuncture still does not work very well.

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.

Thursday, May 20, 2010

The sad case of Macho B

 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.


Sunday, May 16, 2010

Signs of Spring in the mountains.

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.