Microbiota bacteriana e citologia da região traqueobrônquica de bezerros no período neonatal

Abstract

ABSTRACT. - Bronchopneumonia is important for world livestock production and one of the major causes of calf mortality during the first months of life. The preventive and therapeutic measures adopted for the disease in calves in Brazil are usually based on the results of international studies; however there is not enough known which bacteria are implicated. In the first month of life calves show immaturity of their immune system, what has been little studied in regard to pneumonia. The present investigation sought to study neonate bronchopneumonia in calves, to identify which bacteria are present in the respiratory tract of healthy and, with naturally acquired pneumonia calves, to analyze the pulmonary cytological response against pathogens. For this purpose, samples of the respiratory tract were collected by tracheocenthesis. It was noted that the microflora of the tracheobronchial region of healthy and diseased calves was the same, but they were different from the one reported by international papers. The flora was constituted mainly by Staphylococcus sp., Bacillus sp., Streptococcus sp., Pseudomonas aeruginosa and enterobacteriae, allowing to infer that the prophylactic and therapeutic measures adopted internationally may not be as effective for the Brazilian condition. It was also found that newborn calves have an approximate ratio of 1:1 of macrophages and neutrophils in the tracheobronchial region when they were healthy, reaching a ratio of approximately 1:3 of macrophages and neutrophils when they were with bronchopneumonia. Probably, these profiles are characteristic of the age, a period when exists immaturity of the immune system and influenced by management factors which lead to greater inhalation of bacterial agents. RESUMO.-As broncopneumonias são afecções importantes na pecuária mundial, representando uma das principais causas de mortalidade de bezerros nos primeiros meses de vida. As medidas preventivas e terapêuticas adotadas geralmente são baseadas em resultados de estudos internacionais, não se conhecendo as bactérias implicadas nos quadros pneumônicos em animais criados no Brasil. Aliado a isso, no primeiro mês de vida, os bezerros demonstram imaturidade do sistema imune, o que tem sido pouco estudado em quadros pneumônicos. Desta maneira, objetivou--se estudar as broncopneumonias em bezerros neonatos,

Evaluation of Mollicutes Microorganisms in Respiratory Disease of Cattle and Their Relationship to Clinical Signs

“…Bovine respiratory disease was diagnosed when the animal showed ≥2 of the following clinical signs: mucopurulent or purulent nasal discharge, cough, rectal temperature >39.5°C, respiratory rate >40 breaths/min, and increased cranioventral lung sounds or crackle. 6,17,18 The limits of the lung field were 12°i ntercostal space at iliac line and 11°intercostal space at sciatic line. Two experienced veterinarians on our research team performed the physical examinations in all cattle.…”

<b>Influência etária na resposta imunológica de bezerros à vacinação intranasal</b>

“…Os neutrófilos, assim como os macrófagos, atuam na fagocitose e metabolismo oxidativo bacteriano, porém são mais eficientes que os macrófagos e liberam produtos reativos que podem causar injúrias teciduais mais intensas (FADEN;OGRA, 1986;DONNELLY;HASLETT, 1992;BURTON et al, 2005). Hoje, os neutrófilos são estudados no campo da biologia celular a fim de se conhecer melhor sua atuação no desvio da resposta imunológica a afecções e sua importância na regulação da resposta imune (TABIASCO et al, 2002;WHALE et al, 2006aWHALE et al, , 2006bGRIEBEL, 2009;KUMAR;SHARMA, 2010) (GRIEBEL et al, 2005;ACKERMANN;DERSCHEID;ROTH, 2010;GRIFFIN, 2010;BENESI et al, 2013). Diversos receptores TLR estão envolvidos em respostas a vírus, inclusive os TLR-2 e TLR-4 (BARTON, 2007;BASTO;LEITÃO, 2014;MARIN et al, 2014) Uma vez reconhecido o patógeno, estes fagócitos ativados englobam as partículas microbianas e liberam grânulos com substâncias microbicidas desencadeando o metabolismo oxidativo (BURTON et al, 2005).…”

Estudio serológico frente a los virus respiratorios en terneros en un sistema semi-intensivo y su relación con la sintomatología respiratoria

“…Se evaluaron los parámetros vitales: la hidratación y coloración de las mucosas, la presencia de exudado nasal y tos, y se realizó la percusión torácica y auscultación pulmonar. A continuación, los terneros fueron clasificadas en sanos y enfermos o con síntomas de enfermedad respiratoria, cuando presentaban al menos dos de los siguientes parámetros: temperatura alta o equivalente a 39,5; presencia de exudado nasal mucopurulento / purulento; tos; ruidos pulmonares alterados y frecuencia respiratoria por encima de 40 movimientos respiratorios por minuto (Benesi et al, 2013;Gaeta et al, 2017a). Las muestras de sangre venosa se obtuvieron a través de la punción de la vena coccígea o yugular, utilizando tubos de vacío.…”