February 20, 2006

 

Bovine TB threatens cows in US state

 

Farmers in the US state of Minnesota have one more thing to worry about on top of current mad cow concerns haunting the US beef industry.

 

The USDA removed Minnesota's TB Free status in January, saying it would allow the state to reapply for TB Free status two years after the last infected herd has been depopulated.

 

Five beef cattle herd in two counties tested positive for bovine TB. Four of the herds were connected; three have bordering pastureland while the owner of the fourth purchased cattle from the first TB infected herd about two and a half years ago.

 

One wild buck also tested positive for bovine TB late in December 2005.

 

Bovine TB is a chronic respiratory disease affecting cows. The bacteria survive for a long time in moist, cool environments, according to Steve Just, a federal district veterinarian with the Minnesota Board of Animal Health.

 

Infected cattle release the TB organism in sputum, feces and respiratory aerosols and symptoms may take years to develop in cattle.

 

It is unknown where the disease came from. Further laboratory testing is underway to understand how it arrived in Minnesota.

 

Five infected animals were found on the first farm in Roseau County which has since been depopulated, cleaned, disinfected and quarantined, Just said.

 

The Board of Animal Health has been charged to trace all the herds each infected herd owner bought cattle from. The agency has to also investigate all the herds that had contact with each infected herd.

 

This means tracking down information that goes back a number of years, said Just.

 

With a Modified Accredited Advanced status, Minnesota cattle owners have new rules to follow when shipping cattle out of the state.

 

After two years, USDA will reassess the bovine TB situation in Minnesota. If no more cases of TB are found and the federal agency determines that Minnesota has tested enough cattle, the state can be given back its TB Free status.

 

To obtain the certification, the herd owner must test their cattle that are 18 months of age or older. The TB test must be completed again in nine to 15 months, and then annually after that.