Johne’s Control Starts With Good Management

“Johne’s disease has gone from a disease nonexistent in the USA (prior to 1908) to one that affects well over half of U.S. dairy herds,” says Dr. Mike Collins with the University of Wisconsin-Madison School of Veterinary Medicine.

Johne’s is caused by Mycobacterium paratuberculosis and is a slow and untreatable disease. It typically infects calves, but animals show no clinical signs of the bacterial disease until they reach three or more years of age.

The Johne’s bacteria can survive in soil or water for more than a year, but will only replicate inside a host animal. Animals are most susceptible in the first six months of life. The initial infection occurs most commonly at birth through ingestion of fecal material, including feces present in contaminated colostrum or milk.

According to Collins, clinical symptoms of Johne’s include “persistent or intermittent diarrhea and weight loss that is non-responsive to treatment.”  A costly disease, Johne’s can often be an “invisible” issue on your farm. That’s because a majority of the herd can be infected with the disease – and spread it to other animals – while only a few exhibit clinical symptoms. That’s why it’s important to set testing and prevention protocols.

Collins suggests the first and most important way to prevent Johne’s disease is follow best management practices for calf rearing. These include:

Another method of prevention is using a Johne’s vaccination. Discuss vaccination strategies with your local veterinarian.

If your herd is infected, getting rid of Johne’s will probably not be a simple task. In fact, it could take up to five years to economically clean up a Johne’s herd.

Collins suggests that each farm have a Johne’s disease testing program. Ideally, all cows should be ELISA blood-tested at the end of the lactation. Cows labeled positive should be calved in separate maternity pens and colostrum should be tested and labeled. For cows classified as “strong positive” by the ELISA test, culling before calving may be the best option as these cows aren’t likely to survive the lactation.

Collins also reminds producers that testing and control protocols shouldn’t replace good farm management and sanitation practices. Discuss all testing, vaccination and control protocols with your veterinarian.