Tuberculosis in brood sows and pigs slaughtered in Iowa.

Mycobacterium avium was isolated from 21 of 23 lymph nodes with lesions collected from 23 brood sows and from 17 lymph nodes with lesions of 17 pigs slaughtered at an abattoir in north central Iowa. Mycobacterium avium serotype 2 accounted for more than 65% of the isolations in sows and in pigs. Granulomas with acid-fast bacilli were found in 15 of 23 tissues from brood sows and in 13 of 17 lymph nodes from pigs. Similar microscopic lesions were observed in the sows and pigs.