Detection of Mycobacterium avium subsp. paratuberculosis in goat and sheep flocks in Mexico

The slow growth of Mycobacterium avium subsp. paratuberculosis (Map) has hindered its investigation. No data concerning the presence of paratuberculosis in Mexico are currently available. The aim of this study was to identify M. avium subsp. paratuberculosis infection in sheep and goat flocks from several states in Mexico. Twenty-two animals, all manifesting clinical signs of paratuberculosis were obtained from six different Mexican states. Of these, 14 sheep and 8 goats were serologically diagnosed and multibacillary type lesions were identified. On the basis of mycobacteria concentration technique used for ileal mucosa, Map identification was confirmed by means of PCR and bacterial culture.In addition, samples were classified according to the abundance of acid-fast bacteria (AFB) identified in the intestinal mucosa and by the final concentrate of mycobacteria and the amount of DNA obtained. All correlations concerning the abundance of AFB in tissue, AFB recovered in the final concentrate and the amount of DNA obtained were recorded. These findings will allow to predict the amount of DNA which can be obtained by referring to the abundance of acid-fast organisms found in the tissue and, therefore, define the potential of using this method for the purpose of Map characterization. The results of this study indicate that paratuberculosis is widespread among goats and sheep in Mexico.