A study at CornellUniversity examined how long infected animals shed Salmonella into the environment. “Only 5 percent of the calves had observed shedding for more than 30 days,” says Daryl Nydam, veterinarian and epidemiologist at Cornell. Cows appear to shed the organism longer. In the study, 30 percent of the cows shed for more than a month after they had recovered.

“Salmonellosis can be a dose-dependent infection, so shovel stuff up,” Nydam stressed to participants at a recent calf-care workshop in Wisconsin. “Keep the dose in the environment as low as possible.” It also is a good reminder to isolate calves from older animals.