ABSTRACT
To investigate the prevalence of Mycobacterium paratuberculosis [M avium subsp paratuberculosis infection among cattle slaughtered in Ahvaz abattoir, samples were taken from 250 cattle. Before slaughter. sex and age were assessed. Thereafter, samples were taken from ileocecal valve, rectum mucosa, ileocecal lymph node and stool. All smears which taken from these samples were stained by Ziehl-Neelsen method and examined by light microscopy. At first, ileocecal samples were examined; other samples were examined when ileocecal sample was positive. Out of the 250 cattle, 5 [2%] were positive. With the exception of one sample in which the organism was observed in both ileocecal valve and ileocecal lymph nodes in other positive samples the bacteria was observed in only ileocecal valve smear