Frequência de lesões macroscópicas em carcaças de bovinos reagentes ao teste tuberculínico

Abstract

RESUMO:O objetivo deste trabalho foi analisar a frequência de lesões macroscópicas sugestivas de tuberculose em carcaças de bovinos reagentes ao teste intradérmico de tuberculose. Os animais do estudo foram provenientes de rebanhos de exploração leiteira, localizados nos municípios de Perdizes, Patos de Minas, Lagoa Formosa e Uberlândia, Minas Gerais. Foram avaliadas 140 carcaças de bovinos positivos no teste cervical comparativo. Durante o abate sanitário foi realizada inspeção post mortem das carcaças, e as lesões macroscópicas sugestivas de tuberculose foram registradas. Foram avaliados os linfonodos mediastínicos, fígado, pulmão e carcaça. Dos 140 bovinos examinados, 78 (55%) apresentaram algum tipo de lesão macroscópica sugestiva de tuberculose, 38 (49%) ocorreram exclusivamente nos linfonodos mediastínicos, 22 (28%) no fígado e 11 (14%) no pulmão; 5 (6%) carcaças apresentaram lesões no fígado, pulmão e linfonodo mediastínico, e 2 (4%) tiveram lesões no pulmão e linfonodo. Concluem-se que as lesões não visualizadas em bovinos reagentes ao teste tuberculínico podem ocorrer e estariam relacionadas principalmente ao estágio de evolução da doença, tempo insuficiente na inspeção post mortem para detecção, bem como reações inespecíficas para outras micobactérias. PALAVRAS-CHAVE: ABSTRACT:The aim of this study was to analyze the frequency of macroscopic lesions suggestive of tuberculosis in cattle reacting to the tuberculin test. Cattle of this study were from dairy herds located in the cities of Perdizes, Patos de Minas, Lagoa Formosa and Uberlândia, Minas Gerais, Brazil. We evaluated 140 cattle carcasses positive to the cervical comparative intradermal tuberculin test. During the slaughter a post-mortem inspection of carcasses was done, and the lesions suggestive of tuberculosis were recorded. We evaluated the mediastinal lymph nodes, liver, lung and carcass. Of the 140 cattle examined, 78 (55%) carcasses had some kind of macroscopic lesions suggestive of tuberculosis, 38 (49%) occurred only in the mediastinal lymph nodes, 22 (28%) in the liver and 11 (14%) in the lungs; 5 (6%) carcasses showed lesions in liver, lungs and lymph node, and 2 (4%) showed lesions in lung and lymph nodes. We concluded that lesions that were not visualized in bovine tuberculin skin test reagents may occur and are related mainly to the stage of the disease, insufficient time to detect the lesions, and nonspecific reactions to other mycobacteria.

Epidemiological analysis of bovine tuberculosis in the southern region of Rio Grande do Sul from 2000 to 2015

“…In the present study, regarding the 228/331 cases of BTB, the lymph node was the only organ referred to the laboratory, and in 86/331 cases besides lymph nodes, fragments of other organs, such as lung and liver, were obtained. Souza et al (2014) evaluated the slaughtering of 140 cattle and among animals, it could be noted that 78 animals presented some type of macroscopic lesion suggestive of tuberculosis infecction, and in 38 cases, the lesions occurred exclusively in the mediastinal lymph nodes, 22 only in the liver, 11 in the lung and seven carcasses presented concomitant lesions in lymph nodes and liver and/or lung. The significant role of lymph nodes in fighting infections is related to the main pathway of mycobacterial infection (respiratory tract).…”

“…These samples were sent to the LRD-UFPel when the macroscopic lesion did not present typical features of tuberculosis. Slaughterhouses are considered "epidemiological sentinels" in disease control (Baptista et al 2004), but regarding tuberculosis, only 47% of lesions are macroscopically detected during post mortem inspection (Corner 1994), due to different stages of the disease and no time for inspection (Souza et al 2014). The histopathological examination has high sensitivity and specificity in the diagnosis of tuberculosis, being a reliable and fast tool that can help post mortem examination in the diagnosis (Pinto et al 2004, França et al 2013, furthermore, it is important to note the differentiation of other diseases detected in macroscopic lesions, such as actinobacillosis (Andrade et al 1991, Uzal et al 2016.…”

Tuberculosis and Cysticercosis in Brazil: A Review

“…Macroscopic findings are characterized by granulomatous nodular lesions, called tubercles, which develop in any type of organ or tissue. They may lie in any lymph node, although usually in bronchial, retropharynx and mediastinal ones [26] [29] [39], and in other organs, such as the liver, spleen and mesenteric lymph nodes [26] [38]. In the case of lesions in the lungs, miliary abscesses occur.…”