Diagnóstico anatomopatológico histológico de lesões macroscópicas sugestivas de tuberculose bovina

Abstract

The prominent role that Brazil currently enjoys in beef production implies that this product shows high quality and low health risk. In this sense, slaughterhouses constitute an important tool for epidemiological surveillance of diseases, especially zoonotic, among which stands out tuberculosis, due to its large economic and public health impact. The sanitary inspection in slaughterhouses makes the partial or total condemnation of carcasses with suggestive lesions of tuberculosis. However, post-mortem diagnosis is limited, since many inflammatory granulomatous process present morphological characteristics similar to those described for tuberculosis. Laboratory diagnosis, in addition to the inspection procedures would help in making health decisions, besides allowing a more accurate assessment of lesions in order to provide support to the veterinary inspector. The aim of this study was to verify the effectiviness of inspection procedures for the detection of suggestive tuberculosis lesions and determine the prevalence those lesions in cattle slaughtered in Southwestern Bahia. From March to November 2012, 58,268 slaughtered animals were inspected in a slaughterhouse in Vitoria da Conquista. The inspection consisted in a systematic evaluation of the lymph nodes and organs searching for suggestive lesions, through visual and tactile examination with subsequent incision of the lymph nodes. Seventy (0.12%) slaughtered animals presented 99 lymph nodes with suggestive lesions of tuberculosis. To histopathology, 60.6% of the samples had histological lesions characteristic of inflammatory granulomatous process, suggestive of mycobacteria. From samples stained with Ziehl-Neelsen, 10.01% had acid-fast bacilli resistant, and therefore positive for mycobacteria. In conclusion, the prevalence of cattle carcasses with tuberculosis in Southwestern Bahia is low and the procedures in routine post mortem inspection are satisfactory for detecting lesions suggestive of this zoonosis.