The critical management points in beef herds are aimed at protecting young stock from infection and reducing the pathogen load in the environment to reduce risk of transmission to young cattle. Identification and removal of infected animals may be more important in the beef herd because separation of young calves from adults is not practical.
Critical management points for control of Johne’s disease:
Reduce infections by manure management (all manure is suspect).
Reduce exposure to the organism for newborns.
Avoid a manure build up in pastures and corrals where late gestation cows are kept. Clean calving area, keep cow density low, avoid overcrowding. Move new cow/calf pairs to clean pasture as soon as bonding occurs. Avoid keeping high risk or sick cows in common calving area.
Provide clean feed for all cattle.
Avoid manure contamination of feed by using feed bunks and/or hay racks. Do not allow young stock and infected adults to use the same feed, pasture, or water sources. Consider forage crops that had fresh manure applied as fertilizer during the current growing season as a feed risk to young stock. Use separate equipment to handle manure and feed.
Provide clean water for young stock and mature animals.
Supply clean water, not contaminated by potentially infected animals. Use troughs or panels to restrict access to streams and ponds. Divert manure runoff from water sources.
Keep manure from mature animals separate from young stock.
Raise weaned young stock in separate facilities, or pastures not recently used by adult cattle. Prevent transporting bacteria to young stock by people, runoff and equipment. Transport cattle in clean trucks.
Reduce infections by colostrum management.
Feed “low risk” colostrum.
When certain calves need a colostrum supplement, collect from healthy cows, negative on recent tests. Thoroughly clean the udder and teats before collection to avoid fecal contamination. Consider using quality commercial colostrum supplement products.
Reduce infections by management of infected animals (critical for beef herds).
Identify and remove clinical and late stage animals immediately.
Watch for and confirm diagnosis of Johne’s-suspect animals early. Cull test- positives immediately, or segregate them from calving area and young stock. Consider culling or segregating all offspring of these infected dams.
Test to manage subclinical animals and define herd status.
Develop a test strategy to identify subclinically infected animals. Cull, segregate, or manage them to reduce pathogen exposure to others. Strongly consider keeping replacement animals only from test-negative cows. Schedule herd-testing to provide optimal information for herd management, i.e., testing at herd pregnancy examination or herd vaccination time.
Be aware of disease risks when adding animals.
Know the risk in the source-herd for infections one may bring in, i.e., Johne’s, Salmonella, BVD or Cryptosporidia, etc. Consider pretesting, including the source herd, where appropriate. Isolate, observe and test new arrivals before adding to herd, then integrate them into the routine test program
Critical management points for prevention of Johne’s disease:
Prevent infections by closing the herd to animals with an unknown Johne’s infection status.
Purchase from a test-negative herd.
The owner has individual cow/calf records.
The owner uses the critical management points against Johne’s disease.
Pretest mature cow and bull additions.
Recommended only when animals are acquired from an outside source of unknown infection status. Test them two or three times at six to twelve month intervals, depending on the level of assurance desired. Tests will not detect Johne’s in early stages of the disease.
Secure replacements, recipients and additions from herds that are at low risk for Johne’s disease.
Obtain from a herd with negative Johne’s history.
Owner and veterinarian can document Johne’s disease monitoring and the herd has had no cases for past five years.
Acquire from a herd with low Johne’s incidence.
Animals have tested positive for Johne’s disease but herd history and test results indicate a low incidence.
Purchase from a herd that tested negative on a sub-sample of the herd.
Confidence in actual Johne’s disease prevalence will depend on sub-sample size.
Pre- and post-test adult animal additions
Keep them isolated until cleared by tests. Test them two to three times at six to twelve month intervals for increased confidence in their negative status.