Johne’s disease is a persistent and debilitating bacterial disease that affects the intestines of ruminant animals. The common routes of infection are via ingestion of colostrum or milk contaminated by infected cows. For this reason, Johne’s prevention strategies revolve around calf management and herd testing.

Infection can also occur when feed contaminated with manure containing the MAP pathogen is eaten, particularly by youngstock. For this reason, manure application to forages is a potential source of infection.