Prevalência e histopatologia de lesões sugestivas de tuberculose em carcaça de bovinos abatidos no Sudoeste da Bahia

Abstract

O objetivo deste estudo foi determinar a prevalência de lesões sugestivas de tuberculose em carcaças de bovinos abatidos na região Sudoeste da Bahia. No período de março a novembro de 2012 foram inspecionados 58.268 bovinos abatidos em um matadouro frigorífico em Vitória da Conquista-BA. A inspeção consistiu na avaliação sistemática dos gânglios linfáticos e órgãos em busca das lesões sugestivas, por meio de exame visual e tátil com posterior incisão dos gânglios linfáticos. A prevalência de animais com lesões sugestivas de tuberculose ao exame anatomopatológico foi de 0,12%. Os linfonodos mais acometidos foram os pré-escapulares (51,5%) traqueobronquiais (19,2%) e isquiáticos (11,1%). Dos linfonodos com lesões presuntivas, 60,6% apresentaram alterações histológicas sugestivas de micobactérias e 10,0% apresentaram bacilos álcool-ácido resistentes pela coloração de Ziehl-Neelsen, portanto, positivas para micobactérias. Conclui-se que prevalência de carcaças bovinas com lesões sugestivas de tuberculose no Sudoeste da Bahia é baixa, mas remete a necessidade de intensificação das ações para o controle e erradicação da tuberculose bovina no Estado da Bahia.

Isolation and identification of Mycobacterium bovis in cattle slaughtered from an abattoir in Garanhuns, Pernambuco

“…With the progression of the disease, these tubers form large areas of caseous necrosis, and posterior calcification of granuloma is typical (FRANÇA et al, 2013). Silva et al (2014) evaluated 100 carcasses with morphological lesions suggestive of tuberculosis and found that 85% and 15% were classified as caseous and calcified, respectively, corroborating the results of the present study that demonstrates macroscopy of lesions with a caseous aspect sometimes with gritty cut surface.…”

“…80% Laisse et al (2011). Similar findings about AFB location in the giant cells or necrosis area using histological sections were described in cattle (FRANÇA et al, 2013) and goats (SEVA et al, 2002). The scarce number of bacteria in the lesion in histological sections or direct smears may determine the absence of these bacilli, a characteristic observed by Andrade et al (1991), wherein only one lesion with bacilli was identified in the histological section.…”

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

“…The significant role of lymph nodes in fighting infections is related to the main pathway of mycobacterial infection (respiratory tract). The most frequent lesions occurred in the head, neck, and thoracic cavity lymph nodes (França et al 2013).…”

“…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.…”

Difficulties in diagnosis of bovine tuberculosis in suggestive lesions on post-mortem inspection in carcasses

“…In histopathological characterization by HE staining, 66.67% (32/48) were considered characteristic of tuberculosis (Figure 2A), with typical granuloma organized and, according to Arckermann (2013), this type of lesion, TH1 (tuberculoid), is commonly described in cattle, humans and non-human primates, all related to agents of the Mycobacterium tuberculosis complex, with specific epidemiological significance due to pathogenicity. Authors as Jones et al (2000) and França et al (2013) describe tuberculous lesions containing areas of caseous necrosis (with dehydrated and dense content) with central dystrophic calcification, surrounded by giant Langhans cells, mononuclear inflammatory infiltrate (macrophages and lymphocytes), and epithelioid cells. In addition, this immune complex is enveloped by a scar tissue connective capsule, which function is to contain the dispersion of the agent to other tissues.…”