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Your veterinarian can be an excellent resource for identifying management practices that help keep the infection out of your herd and keep it from spreading. Many veterinarians in the country have been trained to complete a Johne’s disease “risk assessment” and to provide resources to design a herd management plan specifically for you.
There are many factors to consider when designing an effective control program. The program should be designed to meet the specific requirements and resources of each producer. Thus programs need not look the same since they reflect:
- The reason
the goats are being raised
- The estimated
herd prevalence of Johne's disease
- The owner's perception of the importance of Johne's disease control relative to other husbandry/health issues
- The ability of an owner to act on diagnostic test results
- The resources available to make management changes to limit the spread of the infection
- The speed with which the owner wants to achieve control of Johne's disease, and whether the goal is to control vs. eradicate the infection.
Critical to any control program’s success is blocking the spread of the infection. This means keeping the most susceptible age group (kids) from being exposed to potentially contaminated manure, feed and water. Ways to help accomplish this include:
- Segregating the herd by level of infection risk so that likely-uninfected kids are not exposed to adults with a higher risk of infection
- Preventing fecal pellets from contaminating feeders and waterers
- Conducting kidding in clean, manure-free areas
- Kidding good condition, healthy (perhaps test-negative) does in a separate location from thin (perhaps test-positive) does
- Cleaning with a phenolic-based disinfectant since M. paratuberculosis is believed resistant to many disinfectants such as chlorine bleach, etc.
- Hand-rearing kids
(Since an effective program should closely reflect the particular resources and requirement of each individual goats operation, the following is meant to provide a general framework only.)
If M. paratuberculosis infection has been confirmed in one goat in a herd, it is likely that other goats are infected as well. The next step should be to decide how aggressive the herd manager needs/wants to be to address these other potential cases and prevent the spread of the infection in the herd.
Not all producers need to test their animals, but to most quickly reduce the prevalence in an infected herd each infected animal must be identified. Test-positive animals should be culled or segregated from the herd; test-positive does should not be bred given the risk of transmission to her kids in utero or via milk/colostrum.
Since a single round of testing may not identify all infected animals, the manager should begin longer term surveillance of the herd to include if feasible:
- Regular assessment and recording of body condition to include weighing or palpation of ribs/spine at least annually.
 Annual AGID or fecal culture of the goats exposed to manure from the confirmed case. - More frequent testing for any offspring of the confirmed case(s) and animals exhibiting weight loss or diarrhea. Segregate of these animals until a diagnosis explaining these clinical signs is reached.
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