ISOLATION OF MYCOBACTERIUM-PARATUBERCULOSIS FROM COLOSTRUM AND MILK OF SUBCLINICALLY INFECTED COWS

Mycobacterial culture was performed on colostrum, milk, and feces from 126 clinically normal cows of a single herd with high prevalence of M ycobacterium paratuberculosis infection. Thirty-six (28.6%) cows were determined to be shedding the organism in the feces. Of the 36 fecal c ulture-positive cows, M paratuberculosis was isolated from the colostr um of 8 (22.2%) and from the milk of 3 (8.3%). Cows that were heavy fe cal shedders were more likely to shed the organism in the colostrum th an were light fecal shedders.