Return to TFB Main Page
Return to Current Edition
Texas Agriculture Archive

October 17, 2003

Brucellosis found in
Henderson County herd

Animal health officials were disappointed, but not surprised in September, when they detected a cattle herd infected with brucellosis in Henderson County, breaking a 13-month stretch during which no newly infected herds were detected in Texas.

Texas and Missouri are the only states in the nation not free of this bacterial disease.

"We are closing in on the last infected herds in Texas, and after months of not finding infection, we were hopeful we might have finally eradicated the disease," commented Dr. Max Coats, deputy director for Animal Health Programs at the Texas Animal Health Commission (TAHC). "With more than 153,000 cattle herds in Texas, finding the last infected herds is like looking for the proverbial `needle in the haystack.' We still may find a few more infected herds in Texas before we join the ranks of the other brucellosis-free states in this national disease eradication program.

"Twice now, we've gone longer than a year without finding a brucellosis-infected herd in Texas," said Coats. "The first time was from July 2000 through December 2001, but soon after, we detected and depopulated four infected herds in Montgomery, Rusk, Henderson and Colorado Counties. Then, after a lull of more than a year, we detected the latest infected herd, in Henderson County, through our routine testing of adult breeding cattle being sold at livestock markets. We're in the process of testing neighboring herds and tracing cattle movement into and out of the Henderson County herd to determine if infection has spread."

Coats explained that, because cooked meat is safe for human consumption, the cows and bulls from the infected herd will be sent to slaughter. The owner will receive payment from the slaughter facility, and an indemnity from the U.S. Department of Agriculture and TAHC to help offset the loss of not only the adult cattle, but also nursing calves. Weaned steers and spayed heifers may be kept, because these animals cannot spread brucellosis, which is transmitted primarily by infected cows during abortion or calving.

"Years ago, Texas had thousands of infected herds, which often were quarantined for up to a year or longer, while we periodically tested the cattle, to ensure all infected animals were removed and slaughtered," said Coats. "During the quarantine period, animals could be sold only to slaughter, creating a hardship for the rancher. There also was the chance that infection could be spread to nearby herds during the quarantine. Now, by depopulating infected herds as soon as possible, we can stop disease spread, and the producer can be in business with new, test-negative animals within weeks."

Coats said Texas continues to apply the "tried-and-true" formula for eradicating brucellosis, which involves vaccinating heifers, testing breeding cattle prior to change of ownership and collecting blood samples from cattle at slaughter. Vaccination is now voluntary in most instances, and ranchers may have their accredited veterinarian administer RB-51 vaccine to heifers four to 12 months of age. (Bull calves do not receive the vaccine, because it can make them sterile.) RB-51 provides heifers protection against brucellosis, but unlike earlier vaccines, it does not create confusion about test results.

"To ensure infected animals are not moved from herd to herd, breeding cattle 18 months or older, or younger cows that are bred or have calved, must have a negative blood test for brucellosis before changing hands at a livestock auction or through private treaty. This 'first-point' testing of cattle has been the most effective and efficient method of finding infection," he said.