Keeping Johnes in mind when feeding colostrum
Feeding calves at least three litres of clean colostrum from the first milking of their own dams within the first two hours of life is an essential component of successful calf rearing.
This method allows the calf to gain essential passive immunity against a range of common disease-causing bacteria and viruses.
Colostrum and milk feeding practices are also important in reducing the risk of calves becoming infected with Johnes Disease (JD).
In JD infected cows, the Johnes-causing bacterium Map can be present in colostrum and milk.
This is through both the direct excretion of the bacteria into the milk and through contamination of the milk with Map contaminated dung.
Colostrum or milk containing the bacteria is a major risk factor for calves becoming infected with JD. Therefore it is essential that calves are fed colostrum or milk which has a low risk of carrying Map.
During calf rearing the following measures should be considered:
1.Test cows individually to identify high-risk cows.