Friday, March 04, 2005

Tb in Michigan: "If we pull away and do nothing, it would get worse"

In this post we have trawled up problems from across the pond. Compare and contrast, the attitude taken to the eradication of tb in Michigan to the latest 'offering' - a 'Framework' and a new 'Committee' from our very own comedy duo - Beckett and Bradshaw.
Michigan is using PCR diagnostic technology as well.

"If we pull away and do nothing, it would get worse".

Prophetic words in 2001 from Michigan State University scientists and vets, attempting a balancing act between hunters and tourism on one side and dairy and beef farmers on the other. The results from a two pronged attack on mycobacterium bovis have now shown fewer Tb cases for the second consecutive year.

In 1995, a hunter discovered lesions in the carcass of a whitetail deer, which were confirmed as Tb. During that winter 20 more infected deer were found. And during a USDA Tb check in Michigan during 1998, the disease was also found in the cattle. This was a huge surprise to the farmers as Tb had been virtually eradicated from the country during the 1970's. By 2001, twenty cases had been discovered by routine intradermal skin testing the cattle herds and eleven of those had opted for 'depopulation' - whole herd slaughter.

Farmers and scientists blamed the cross contamination or transmission of this infectious bacteria on the feeding and 'baiting' of the deer populations. Hunters were sustaining larger deer populations by supplementary feeding during the winter, and then drawing them out of the woodland cover, by using sugar beet, carrots and corn for 'close shots' in the autumn.

This close contact of the deer at communal feeding, the scientists felt encouraged the spread of Tb within the deer population, and sustained by this extra feeding, the over populated deer then spilled out into the cattle pastures. Any residues of infected saliva etc. on the remains of the 'bait' was then available to cattle.

The two pronged appraoch adopted by Michigan involved reducing the population of whitetail deer drastically, and they banned the feeding and 'baiting' of the animals in some areas. The number of infected deer carcasses fell. More hunters' licenses were granted - less deer meant less tb, and the compensation for slaughtered cattle was increased to $4000 per head.

Michigan scientist Dr. Mitch Palmer suggested that they were breaking new ground, because "The established dogma was that you couldn't maintain Tb in a wildlife population" .
His partner is concentrating on studying transmission of the disease via the feed piles laid out to encourage the deer in range of the hunters' rifles.
"The only way to control Tb in the wild is to rely on the hunters."

Like the UK, farmers in Michigan dread finding Tb in the herds. When one animal tests positive, the whole herd and the farmer's livelihood can be destroyed. This calls into question the management of the wildlife source - the whitetail deer. Farmers point out that the ban on supplementary feeding and 'baiting' the deer is only applied rigourously in one corner of the State, but allowed to continue 'at a reduced level' else where.

"They have to do away with ALL baiting. It's like being a little bit pregnant - it ain't gonna work", said one farmer.

That view is also held by the Michigan Farm bureau, representing 17,000 cattle farmers. A one sided policy will not work, but to help Michigan farmers, cattle compensation has been increased (to $4000) and the State covers all testing and veterinary checks. USDA stresses the importance of regaining and retaining its Tb free trading status'.

In 2001, Michigan had tested 39,200 white tailed deer and found a total of 285 with confirmed tb. The Department of Agriculture has conducted 156,674 tb tests on cattle, goats and bison and 8,400 privately owned cervids. IOWA University warned in 1996 of the folly of countries (like the UK) who allowed a wildlife reservoir of tb to flourish, pointing out that such actions were putting at risk decades of eradication work on the disease. The Tb eradication project in Michigan involves a multi-agency team of experts including the Department of Agriculture, Community Health, Natural Resources, Michigan State University and the US Department of Agriculture. Co-ordinator of the project is Bob Bender, an ex dairy farmer who served 13 years with the State Legislature.

"This is a hugely expensive project to save livestock and wildlife", said Bob Schmitt, a vet with the Department of Natural Resources, "but if we pull away and do nothing, it will get worse".

More on this story and Michigan's use of the PCR at:

www.freep.com/news/health/tb29-20010129.htm
www.maes.msu.edu/articles/bovine2005.pdf
.

1 comment:

DICKFORTH said...

If you do nothing ,nothing will happen but in the case of TB it will get worse, we have allways known the USA is pro-active in helping its own, prehaps next time Tony Blair ram`s his nose up Bush`s
arse and think`s he is the next President of the UK a pro-active help your own country policy will rub off. At least the Yanks know how to kick ass!!