Impact on a dairy herd

A US study found that Johne's infected animals:

• Gave on average 4,000 kg less milk in their lifetime
• Were 5 times more likely to be lame
• Were 2 times more likely to develop mastitis / SCC problems
• Were 1.8 x more likely to develop digestive problems

_{Source: Villarano M.A. and Jordan E.R. (2005). Production effects of MAP in dairy cows. Proceedings of International Johne's conference.}