Texas livestock health officials, striving to protect Texas' hard-earned cattle tuberculosis (TB)-free status, have adopted new cattle entry, testing and movement regulations that go into effect Saturday, October 13. The 13 commissioners for the Texas Animal Health Commission (TAHC) have tightened regulations, due to concerns about the recent findings of cattle TB infection in two New Mexico dairies, a Colorado bucking bull herd, and an Oklahoma beef herd. Additionally, over the past two years, at least five infected cattle herds and infection in free-ranging deer have been identified in Minnesota. For several years, Michigan also has waged war against TB in both cattle and free-ranging deer.
Texas originally achieved cattle TB-free status in 2000, only to lose it in 2002, after two infected cattle herds were detected. To regain the state's status and ability to move and market cattle without restrictions, a rigorous TB testing program was initiated to detect any remaining infection and provide proof of sufficient disease surveillance. In October 2006, Texas regained its TB-free status, after testing 342,937 cattle in the state's 818 dairies, and 128,489 head in 2,014 beef purebred and seed stock herds.
"Reclaiming TB-free status was hard work for Texas producers and veterinary practitioners who participated in the testing program, and for TAHC and U.S. Department of Agriculture staff in Texas," said Dr. Bob Hillman, TAHC executive director and Texas' state veterinarian. "It's not enough to just find and eradicate TB." He stressed that proactive measures are needed to prevent reintroducing this contagious, bacterial disease that can cause lesions on an animal's lungs, lymph nodes and other internal organs.
"We must be able to find the disease quickly if it is re-introduced and trace those animals that may be the source of infection or be exposed to TB," he said.
Dr. Hillman said the new TAHC regulations include:
* lowering the TB test-eligible age from six to two months for sexually intact dairy cattle entering Texas. These animals also must have be officially identified individually and be accompanied by a certificate of veterinary inspection stating they tested negative for TB within 60 days prior to entering Texas. Sexually intact cattle less than two months of age must have an entry permit and go to a designated facility, where the animals will be held until they are tested negative at the age of two months.
* forgoing TB testing on out-of-state dairy cattle delivered to an approved feedlot in Texas for finish feeding for slaughter only, unless the animals are from TB-infected herd. These dairy feeder animals must be identified, and have a TAHC entry permit and certificate of veterinary inspection.
* identifying all Texas dairy cattle regardless of age--with an official or TAHC-approved identification device prior to movement within the state.
* requiring TB tests for Mexican-origin (or "M"-branded) steers that are recognized as potential rodeo and/or roping stock, and entering Texas from other states. These steers must have had a negative TB test within the previous 12 months, and have a certificate of veterinary inspection issued within the previous 30 days.
Dr. Hillman explained that dairy animals are managed in close confinement and, therefore, are at greater risk for TB exposure if they have an infected herd mate. Lowering the TB test-eligible age for imported dairy cattle will help reduce the chances of introducing a TB-infected animal into a dairy.
"Imported dairy cattle fed for slaughter will not rejoin a herd," said Dr. Hillman. "Therefore, their risk to other cattle is minimal. If TB lesions are detected in the animals' carcasses at slaughter and infection is confirmed, the required identification will make it possible to identify the source of the animal. The identification also will aid in tracing the movements of the animals and assist in determining which other animals may have been exposed."
"During their lifespan, dairy animals may be moved numerous times among different production facilities. Having dairy animals identified can be a boon, if TB infection is detected," said Dr. Hillman. "Animal identification also greatly enhances our ability to trace back the movements of infected animals, so we can conduct epidemiological investigations and disease surveillance more efficiently and effectively."
"Regulations already were in place for importing steers from Mexico, requiring them to be "M"-branded, and then retested annually in Texas, if they are used for rodeo or roping activities," said Dr. Hillman. "The new regulation addresses situations in which Mexican-origin steers have been maintained in other states. Requiring these animals to be test-negative within the previous 12 months provides greater assurance that the animals will not introduce TB into Texas herds."
He advised producers to avoid commingling U.S. cattle with Mexican-origin rodeo steers or feeder cattle. Although these imported animals enter under strict TB testing requirements, he noted that TB has not been eradicated in Mexico and there is significant potential for disease exposure.
"Cattle tuberculosis infection may be a 'silent' infection. For years, the infected animal can appear healthy, and only when it is tested or slaughtered, is there evidence of infection. By then, the infected animal may have exposed many herd mates to this insidious disease," said Dr. Hillman. "We must act proactively to prevent disease introduction and ensure the ability to identify sources of the disease, in order to maintain Texas' well-deserved TB-free status."