Experts say it was bound to happen: The H5N1 bird flu that ravaged dairy herds in 13 states was inevitably going to arrive in California. But exactly how it happened is still being investigated by the state. However, Anja Raudabaugh — the chief executive of Western State Dairies, a trade organization for California dairy farmers — was able to confirm one of the stories that has been circulating.
7 million dairy cows. According to the USDA, on Jan. 1 this year, there were roughly 5.1 million cows, steer, bulls and calves in the state. Ray Souza, a former dairy farmer in Turlock, Calif., who once oversaw a farm with more than 1,000 cattle before retiring in 2015, said he moved cows frequently. Depending on milk production, he might have moved old cows off and new cows on every day, or every week. It all depended on productivity.