Use of a new bulk tank milk test to measureprevalence of Johne’s disease in Utah and the intermountain west

The objectives were estimation of dairy herd-level prevalence of Johne's disease (JD) in Utah and parts of surrounding states, and estimation of the sensitivity of a single bulk-tank milk test for detection of JD. Johne's disease is a chronic intestinal disease of dairy cattle; effects can include milk production loss, weight loss, diarrhea, death, and increased culling risk. Most US dairy farms do not test for the disease, therefore prevalence is unknown.