Local authorities want to know why a gray fox lay immobile
in someone’s Wisconsin backyard. The fox was
put down and its body was sent to the National Wildlife Health Center
Laboratory, in Madison,
Wisc.
There, Carol Meteyer, a wildlife pathologist at the lab,
began to unravel the fox’s mystery. On a steel table in her basement lab, she
began a necropsy, or animal autopsy, on the fox’s remains. Each of the fox’s
organs held a possible clue to what had caused the fox to act so oddly.
She drained urine from the fox’s bladder so it could be
tested for the tell-tale crystals of antifreeze poisoning. A cat and a raccoon
had died in the same area at about the same time, and antifreeze, while toxic,
tastes sweet to animals, and they will drink it if they find a puddle of it.
Meteyer did not find crystals in the fox’s kidneys, which would also occur if
the fox drank anti-freeze, so she put antifreeze poisoning lower on her list of
possible causes.
Infections tend to cause a swollen spleen, and this fox’s
spleen looked normal, Meteyer said. The fox’s stomach was empty, so other types
of poisoning dropped lower on her list as well. Poisoned animals often have a
stomach full of human food, like stew, Meteyer explained, that the poisoner has
spiked. Diarrhea is often a sign of canine parvovirus, but she found no diarrhea
in the fox’s bowel.
That left canine distemper as a likely cause. Meteyer would
look for virus inclusions, basically bumps, on the fox’s inner eyelids and
bladder. Distemper can also leave tell-tale clues in the brain, she explained.
Meteyer was part of one of four teams of researchers who
explained their work at the lab to our conference tour group. The lab deals
with all sorts of wildlife diseases, from plague to West
Nile virus to white nose syndrome in bats to monitoring for avian
influenza. These researchers not only diagnose illnesses, but sometimes they
discover new disease-causing organisms in the process. The lab’s job doesn’t
stop with diagnosis, but goes on to containment strategies, and even vaccines.
Meteyer’s work with the fox was not done by the time our
group left the building, but it offered an example of the wildlife disease mysteries explored at the National Wildlife Health Center.
Recent Comments