Abstract
Thirty-three pigs were investigated which were diagnosed with the localized-type of mycobacteriosis. The gross lesions (caseous necrosis) were recognized only in mesenteric and/or mandibular lymph nodes during routine meat inspection of all cases. Lymph nodes from seven locations, including the mesentery and mandible, and organs (lungs and spleen) were examined; and lesion and bacteria distributions were histopathologically and bacteriologically surveyed. These methods authenticated only 8 animals (15.2%) as proven instances of the localized-type.Mycobacterium avium (M. avium) and/or granulomatous lesions were demonstrated in the lungs and the tracheobronchial and digestive lymph nodes of 21 animals (63.6%). Neither lesions norM. aviumwas demonstrated in the spleen of any animal. These results indicate the possibility thatM. aviumspreads over the lungs through the respiratory tract. Granulomatous lesions in the iliac and inguinal lymph nodes orM. aviumisolates from these organs were recognized only in female pigs, indicating the suspection of sexual influence onM. aviumdistribution differences.
