Penn State tests dairy herd for avian influenza
Cows not symptomatic, but testing is important for disease detection, officials said
24 July 2024
3 minute read
By: Animal health experts in Penn State’s College of Agricultural Sciences have announced that — out of an abundance of caution — they will test the University’s dairy herd for highly pathogenic avian influenza, or HPAI, under a voluntary state testing program, according to a news release from the university.
The announcement comes amidst an outbreak of bird flu that has affected dairy cattle in more than a dozen states since March. As of July 19, the virus had not been found in Pennsylvania dairy herds, according to the US Department of Agriculture and state animal health authorities.
The Pennsylvania Department of Agriculture has encouraged all dairy farms in the state to enroll in its Lactating Dairy Cow Health Monitoring Program. The voluntary program is aimed at providing critical data on the status of dairy herds in Pennsylvania and detecting HPAI as quickly as possible should it arrive in the commonwealth.
“The state herd monitoring program calls for conducting a weekly test of milk from a farm for three weeks,” said extension veterinarian Ernest Hovingh, who is also a clinical professor of veterinary and biomedical sciences and director of Penn State’s Animal Diagnostic Laboratory. “If all tests are negative and no clinical signs of the disease are observed, the herd is considered ‘unaffected.’ At that point, weekly testing would continue, to ensure that the herd remains free of the virus.”
He noted that unaffected herds are cleared for interstate transport of animals without any additional testing. For herds that do not participate in the monitoring program, Department of Agriculture regulations require testing of animals prior to movement across state lines.
“Because Penn State does not move dairy cows across state lines, our herd has not been subjected to testing so far,” Hovingh said. “But participating in this program will allow us to determine if our herd is in fact HPAI-free, as strongly expected, and also will provide additional data to inform state and national surveillance efforts.”
The chances of getting a positive test result are very remote, he added, but if that happens, Penn State and state officials will immediately investigate further.
Penn State attending veterinarian Jacob Werner, who oversees the health and well-being of all University livestock, said he and managers at the Penn State dairy barns have seen no signs to suggest that the virus is present in the herd, but it will be good to have testing data to confirm those observations.
“We have a biosecurity plan in place to minimize the chances of bringing any diseases, including HPAI, into our herd, and we screen for sick cows regularly and consistently,” Werner said. “Drops in feed intake and milk production are two hallmark signs of most affected herds, and we monitor closely for those symptoms. We also don’t import any animals into our herd, which appears to be the biggest risk factor for introducing HPAI infection to dairy herds.”
Even in the unlikely event that the testing of Penn State’s herd brings back a positive result, Hovingh pointed out that in accordance with the U.S. Food and Drug Administration’s Pasteurized Milk Ordinance, milk from sick cows does not leave the dairy and, therefore, does not enter the food supply.
“In addition, all milk from Penn State cows is pasteurized before being sold for human consumption,” he said. “Numerous studies have shown that pasteurization inactivates pathogens such as avian flu viruses, and the Food and Drug Administration has confirmed that pasteurized milk and milk products are safe for human consumption.”
Penn State will release the HPAI status of its dairy herd after the initial series of three weekly tests is completed, Hovingh said.
