Researchers Aid Efforts to Identify TB in Michigan DeerBy
Agricultural Research Service animal
health experts are helping federal and state officials investigate the source
and extent of tuberculosis in white-tailed deer in Michigan.
The ARS scientists have joined USDA's Animal
and Plant Health Inspection Service (APHIS), the
Michigan State Department of Agriculture
and the Michigan Department of Natural
Resources in the study. Five Michigan counties have reported wild
white-tailed deer infected with Mycobacterium bovis, the organism that
causes cattle tuberculosis. TB can spread from animals to humans.
Until now, no recognized wildlife reservoir for tuberculosis has existed in
the United States, according to Diana L. Whipple, a microbiologist at the ARS
National Animal Disease Center in
Ames, Iowa. The outbreak of tuberculosis among Michigan deer and elk threatens a
successful cattle TB eradication program that began in the United States in
Currently used skin tests do not detect all of the animals with TB. A blood
test for diagnosis of TB in deer and elk also misses infected animals and is
quite expensive. The primary means of detection of TB in cattle is carcass
inspection after slaughter, but not all infected cattle show signs of disease.
For a successful eradication program, other tests must be developed and used in
conjunction with meat inspection.
In a few months, ARS researchers will evaluate a new blood test for deer
developed by Australian researchers. In the meantime, they recommend more
efficient use of tools to detect cattle TB. More infected cattle can be detected
by using both the skin and blood tests than by using either test alone.
Regulatory officials also recognize the importance of minimal handling while
administering these tests. Humans don't get tuberculosis from eating or drinking
milk from infected animals because pasteurization and appropriate cooking
temperatures kill the M. bovis organism.
Scientific contact: Diana L. Whipple, ARS
National Animal Disease Center,
Ames, Iowa, phone (515) 239-8377, fax (515) 239-8458,