The United States Department of Agriculture has introduced a new regulation requiring a test for avian influenza on all cattle crossing state lines.
It comes after dozens of dairy cattle have been identified as infected with the virus that was previously believed to be almost exclusively spreading among birds, and in particular from migrating birds to farmed chickens and turkeys.
The government said there have been more than 1,100 outbreaks of highly-pathogenic avian influenza on poultry farms.
Under the Federal Order, dairy cattle must receive a negative test for Influenza A virus at approved laboratories before interstate movement. Positive test results must be reported to USDA APHIS (Animal and Plant Health Inspection Service) by laboratories and state veterinarians.
