As hunters transported their kills home
last November, the heads of their deer that were collected at
highway check stations located throughout the state. In response to
concerns over bovine tuberculosis and its effect on Michigan deer,
the Michigan Department of Natural Resources asks hunters to
voluntarily leave their deer heads at the checkpoints, especially
if they hunt in the northeast part of the Lower Peninsula. The
so-called core area of the bovine TB problem, centered in Alcona,
Alpena, Montmorency and Oscoda counties, has been the focus of much
Bovine tuberculosis, an infectious disease found in white-tailed
deer, elk, and domestic livestock, has been a problem since the
19th century when it was introduced by European cattle.
According to DNR records, TB was the leading cause of death in
humans in 1917. The outbreak was initially brought about by people
drinking raw milk from infected cows. Before 1994 there were very
few known cases of infected deer, but since then, nearly 500 deer
heads have tested positive for bovine TB in Michigan. Last fall, 28
deer heads tested positive, most of which were collected in the
core area of the state.
Although other states have seen problems with the disease in
livestock, Michigan is the only place where wildlife have
endemically contracted bovine TB.
In an effort to understand and control the spread of the
disease, then-Gov. John Engler enacted the Michigan Bovine
Tuberculosis Eradication Project in 1998. The project includes the
help of experts from the Michigan departments of Agriculture,
Community Health, and Natural Resources, as well as Michigan State
University and the U.S. Department of Agriculture.
From the highway check stations, deer heads are transported by
truck to the MSU/DNR Deer Head Facility in East Lansing where
testing has been done annually for the past five years.
The heads are given a visual inspection of tooth condition to
verify age, and are matched with their corresponding bar codes in
the facility’s database. This ensures that the deer being
tested is the same deer that was supplied by a specific hunter from
a specific part of the state. Technicians then slice into the lymph
glands, located in the necks of the deer, and look for the telltale
nodules and gross lesions characteristic of bovine TB. If
suspicious samples are found, they are sent to the pathology lab at
MSU for further testing.
“The first concern is public health,” said Bridget
Patrick, a bovine TB eradication coordinator for the MDCH.
“The second is the economic viability of both the livestock
industry and travel and tourism.”
Because of modern pasteurization and meat inspection laws,
humans are not particularly at risk for contracting the disease.
But because livestock often share fence lines with wild deer, there
is a high risk of cattle becoming infected by common feeding
“It directly impacts the cattle industry and their ability
to market livestock,” Patrick added. Because the state has a
presence of bovine TB, other states and countries may be hesitant
to trade freely, or to participate in cattle breeding or
Public opinion is also a major concern when it comes to tourism;
if hunters fear the disease, the economy of northern Michigan may
suffer. There were nearly fifty thousand fewer hunters in the core
area of the state this year.
A study by the Michigan Travel, Tourism, and Recreation Center
at MSU suggests that the affected parts of northern Michigan lose
$25 million annually in hunting related income alone.
In an effort to stop inter-animal contamination, the use of food
or bait piles larger than two gallons has been banned throughout
the state. Even farmers are required to remove hay and food piles
from their fields.
Scientists at Michigan State are also checking for chronic
wasting disease, a disease similar in deer to mad cow disease in
cattle and scrapie in sheep.
Gov. Jennifer Granholm signed an executive order last year that
created a task force to monitor CWD among the wild deer
Research indicates cannot be transmitted to humans, and though
Michigan has had cases of CWD, no one is taking any chances. Two
years ago Wisconsin witnessed an outbreak, and its hunting industry
took major losses. The Wisconsin DNR offers cash awards to hunters
who bring in infected animals.
Because Michigan’s annual hunting-related income averages
between $500 and $800 million, officials are working to ensure that
bovine TB and CWD are kept in check. As the Michigan Bovine
Tuberculosis Eradication Project states, complete eradication of
bovine TB is the goal.