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bison which have wandered into Idaho have been immobilized
with Carfentanil, a drug in the opiate family. This drug is
administered in conjunction with the sedative, Xylazine. Both
drugs can exhibit extreme side effects in animals, possibly
resulting in death. This drug combination is also used within
the YNP for immobilizing bison when biologists collect samples
for research.
Carfentanil is the most potent drug and is potentially toxic
and lethal to humans. It is recommended that any game animal
which has been drugged should not be consumed for at least
45 days. However, the literature states that it probably not
wise under any circumstances to consume animals that have
been immobilized with Carfentanil. There have been reports
of humans developing symptoms of drug toxicity from consuming
animals given immobilizing drugs. As little as 20 ug (micrograms,
an almost invisible drop) of Carfentanil is lethal to humans.
There are several major side effects which bison may suffer
from this drug, respiratory depression, hyperthermia (increased
body temperature) and "recycling". This "recycling"
occurs because Carfentanil has an affinity for fatty tissues
and is stored there. It also has a longer half life than the
antidote (or antagonist) Naltrexone. Once the Naltrexone has
been completely metabolized and cleared from the body, Carfentanil
can be released from the fatty tissue and recirculate though
the animal causing a renarcotization event. This event could
occur several hours to days after the intitial immobilization.
If there are no trained personnel watching over the animal
when this occurs, it could suffer injury or death as a result.
Xylazine can exhibit major side effects such as hypotension
(abnormally decreased blood pressure), bradycardia (slowed
heart rate), and disruptions in body temperature regulation.
Respiratory depression may also occur, especially when used
in conjunction with drugs such as Carfentanil.
Bloat and decreased gastrointestinal mobility can occur with
these drugs particularly in ruminants such as bison. It is
recommended that bison and other ruminants who have been immobilized
be placed either in a sternal position or on their right side
to prevent this. Bloat is caused when excess gas resulting
from normal fermentation accumulates in the rumen of ungulates.
This causes the rumen to enlarge and and compress the diaphragm
and lungs resulting in respiratory impairment.
BFC volunteers were able to document abuse and disrespect
of immobilized bison. Several Idaho law officials each took
a turn posing for pictures while sitting atop a bull and holding
his head up by his horns, trophy style. We did not witness
any monitoring of vital signs or medical attention as recommended
in the literature. Nor was much attention paid to body position,
critical for bison.
Although we have allowed to witness and document the immobilization
of bison in Idaho, we have been prevented by law enforcement
and park personnel from witnessing the recovery and release
of these bison within YNP. The disposition of a particular
bull was especially suspicious as we had been given conflicting
information regarding his recovery. And, one week after his
release a grizzly sow and her cubs were seen feeding on a
large bison bull carcass near the area where he had been susposedly
released.
The safety of Carfentanil use in bison is debated even among
the experts. BFC is concerned that bison immobilized with
this drug have not been properly monitored and may have suffered
fatal outcomes. We are also concerned that tribes might receive
meat from bison who were administered this drug without any
precautions or warnings.
What are park officials trying to hide when they prevent our
volunteers from witnessing the release of these bison after
immoblization? And is it safe for endangered predators such
as grizzly bears and eagles to consume these bison carcasses
after they've been drugged? The government agencies involved
in this activity have declined to comment. BFC will continue
their efforts to monitor and document all actions perpetrated
upon migrating bison.
Sources
Aiello, Susan E. (1998). "The Merck Veterinary Manual",
Eighth Edition. Merck & Co., Inc., 1680-1681.
Bistner, Stephen I., Ford, Richard B., Raffe, Mark R. (--)
"Handbook of Veterinary Procedures and Emergency Treatment",
Seventh Edition. 12-13, 224-225, 854-857, 942-943, 946-947,
956-957.
Jenkins, Stephen H. (1995) "Carfentanil, Bison, and Statistics:
The Last Word?", Letter to the Editor, Journal of Wildlife
Disease, 31(1) 104-105.
Kreeger, Terry J. (1997) "Handbook of Wildlife Chemical
Immobilization". International Wildlife Veterinary Services,
Inc. 11, 26-28, 33-34, 36-37, 47-49, 51-54, 82-83, 86-87,
127.
Plumb, Donald C. (--) "Veterinary Drug Handbook",
Second Edition. Iowa State University Press / Ames. 345-348,
427-428, 636- 640.
Roder, Joseph D. (--) "Veterinary Toxicology". Butterworth
/ Heinemann. 316-317, 322-323. |
