Controlling Johne’s
Disease step by step

By knowing how Johne’s is spread, milk producers can set up a program to prevent and control this costly disease.

by Dr. John H. Kirk

• Calve in a clean, dry maternity area. If you are wondering whether it is clean and dry enough, kneel down in the bedding. If your knee comes up wet and covered with manure, the maternity pen needs some work. Frequent cleaning and replacement of bedding is the key.
• Remove the newborn calf from the dam before it has a chance to nurse or even attempt to nurse. Don’t let the calf ingest milk from a manure-covered teat. Ingesting manure greatly increases the risk of Johne’s transfer.
• Avoid keeping older cows with diarrhea and weight loss in common maternity pens, as they are the high-risk cows for shedding Johne’s bacteria. Manure from cows with Johne’s contains zillions of infective bacteria.
• Have separate maternity and hospital pens to reduce exposure to newborn calves.

    Step 2: Provide clean feed for young stock and mature animals.

• Do not feed potentially contaminated feed from adult cows, including refused feed, to young stock. The risk of infection is greatest in the youngest animals, meaning that it takes a smaller dose of Johne’s bacteria to infect a young calf compared to a yearling.
• Use separate equipment to handle feed and manure. The same tractor should not be used to scrape a cow alley and then be used to push up feed. Manure is the source of infection.
• Reduce crossing cow alleys and feed aleys with vehicles. Again, moving manure from one place to another is the same as moving the Johne’s bacteria from one place to another.
• Keep adult cows and young stock in separate pastures. Provide separate sources of feed and water.

    Step 3: Provide clean water for both young and mature animals.

• Supply clean water to all animals.
• Use trough and individual waterers.
• Restrict run-off from pens or corrals, particularly run-offs from adult animals that may enter locations where young stock are housed.

    Step 4: Keep manure from mature stock from contacting young stock.

• Raise young stock in separate areas from older animals to prevent the potential exposure of Johne’s bacteria in old stock manure.
• Prevent manure run-off from mature animals from reaching young stock. Remember manure and water both run downhill, so put the young stock uphill from older animals.

Johne’s bacteria by colostrum and milk management
    Step 1: Feed “low risk” colostrum.

1) In manure. Controlling manure flow and separating calves are key.

2) By colostrum and milk. Feed calves “low risk” colostrum and milk.

3) Through infected cows. Test and manage infected animals.

• Use only colostrum from healthy cows that were negative on a recent Johne’s test.
• Give the calf only colostrum from its dam… no pooling. Pooling increases the chances of infecting many calves from a single infected dam.
• Save colostrum from “low risk” cows by freezing or refrigerating.
• Consider using colostrum supplements particularly if your herd is highly infected.

    Step 2: Feed “low risk” milk.

• Feed a milk replacer instead of unknown status milk.
• Pasteurize milk or use milk only from cows with recent negative Johne’s test.
• Thoroughly clean the udder and teats before collecting milk for calf feeding.

    The final area of consideration is the management of infected cows to reduce the chances of spreading infection to other herd-mates and young stock. Again, many of these suggestions should be included in any herd biosecurity program.

Management of infected cows
    Step 1: Identify and remove clinical and late stage animals as soon as possible.

• Watch for and confirm the diagnosis of Johne’s suspects early.
• Test-positive cows should be culled or at the very least segregated from maternity areas and young stock.
• Colostrum from test-positive cows should not be fed to any calves.
• Calves born to test-positive cows are at higher risk for Johne’s Disease so consideration should be given to selling them rather than keeping them for herd replacements.

    Step 2: Test to manage subclinical infections and define your herd status.

• Test a portion of the herd to determine the herd status. Testing as few as 30 adult cows can give an accurate prediction of the level of herd infection.
• Cull, segregate or manage the test-positive animals to reduce exposure to other animals in the herd, particularly the young stock.
• Develop a plan with your veterinarian for testing of adult cows on a regular basis.

    Step 3: Be aware of the risk when adding new animals to the herd.

• Ask your veterinarian about the risk from adding cows with Johne’s, salmonella, Strep ag, Staph aureus, BVD, mycoplasmas and footwarts.
• Consider pre-testing animals before bringing them into your herd.
• Isolate all newly arrived animals before mixing them with your herd. Delay mixing until you have tested for high-risk diseases such as Johne’s.

    This may seem like an overwhelming list of things to do just to control Johne’s Disease. By working with your veterinarian, you can break the list down to parts that can be managed. Over time you can develop a plan that will greatly reduce the risk of Johne’s Disease in your herd. 

Dr. John H. Kirk, DVM, MPVM is an Extension Veterinarian with the University of California Davis School of Veterinary Medicine. He is based at the Veterinary Medicine Teaching and Research Center in Tulare, Calif. He can be reached via email at: jkirk@vmtrc.ucdavis.edu.

More information on Johne’s Disease can be found at the U.S. Animal Health Association's National Johne’s Working Group at www.usaha.org/njwg/njwg.html or at the Johne’s Information Center at www.vetmed.wisc.edu/pbs/johnes/