Examination of Mycobacterium avium subsp. avium distribution in naturally infected hens by culture and triplex quantitative real time PCR

Abstract

Mycobacterium avium subsp. avium (MAA) is the etiologic agent of avian tuberculosis, a chronic contagious disease described in a wide variety of domestic and wild bird species. The aims of this study were to assess the advantages of triplex quantitative real time PCR (qPCR) in comparison with culture testing for distribution of MAA in the organs of hens displaying varying degrees of clinical symptoms of the disease. From one small flock of ten hens and one cock with a history of weight loss, 98 tissue samples were examined in total. Pathological lesions were observed in six hens from which two were clinically ill. A total of 12 samples were positive by culture and 16 were positive by IS901 and IS1245 qPCR, confirming MAA infection. In conclusion, qPCR was a faster and more reliable alternative method in comparison with conventional culture analysis. Due to the detection of MAA in the muscle tissue of one hen, consumption of under cooked meat originating from infected fowl could pose a threat to immunosuppressed individuals.