California officials diagnosed seven cows from three Fresno County herds and one cow from a San Bernardino County herd with bovine TB in 2008. By late 2009, California had TB-tested approximately 419,000 cattle. Two herds were depopulated and over 8,000 cattle killed in the investigation. Two affected herds were put on a test-and-removal program.
In September 2008, California was classified as Modified Accredited Advanced (MAA). That status requires veterinarians and producers to check the TB requirements of receiving states when moving cattle out of California.
Texas detected an affected dairy herd during private testing to sell the herd in 2009. Six infected cows were identified, with the strain type matching that detected in old roping steers of Mexican origin recently slaughtered from a nearby feedlot.
Nebraska detected an affected cervid herd and an affected beef herd, both through slaughter surveillance, in 2009. Because they have different TB strain types, the infections were not related.
Minnesota has detected 12 affected beef herds since 2005, and 25 infected free-ranging white-tailed deer. It received split-state status in September 2008 with a Modified Accredited (MA) zone around the affected herds and an MAA zone for the rest of the state.
Michigan has detected 49 affected cattle herds and four cervid herds since 1998, says Bridget Patrick, risk management specialist for the Michigan Department of Agriculture. The state has three zones: the infected area classified as MA; the Upper Peninsula, which is TB-free; and the rest of the state, classified as MAA. Infected free-ranging white-tailed deer continue to be detected, and infection has been found in several other wildlife species. In late April, federal officials decreased the number of Michigan counties classified as MA “because we have a good program in place and more counties were eligible to move up in status,” Patrick says. Michigan is the only state, she adds, that requires every cow to have an electronic identification ear tag when it leaves the farm.
New Mexico detected one new TB herd in 2008. The state has split-state status: an MAA zone around Curry and Roosevelt counties and the rest of the state TB-free. Although there are no herds with TB at this time, federal rules require New Mexico to maintain its split-state status until next year, says Bobby Pierce, deputy director of the New Mexico Livestock Board.
Indiana detected three infected cervid herds through slaughter surveillance in 2009. An investigation into a beef cow located two miles away infected with the same TB strain did not identify an affected herd.
New York detected and depopulated a captive deer herd after a routine test was positive for TB in 2008.