Passive immunity in cattle against enterotoxigenic Escherichia coli: serologic evaluation of a bacterin containing K99 and F41 fimbriae in colostrum of vaccinated females and calf serum

Abstract

A bacterin from enterotoxigenic Escherichia coli (ETEC), containing fimbriae K99 and F41, was produced and its capacity to induce anti-K99 and anti-F41 antibodies in colostrum of vaccinated cows and in calf serum, and the persistence of these antibodies in neonates were determined. Three experiments were performed on two commercial farms. In all experiments animals were allotted randomly to the blocks, each block consisting of two pregnant females (a vaccinated one and a control one) and their respective calves. In experiment A (farm 1), comprised of 18 blocks, the animals received a vaccine dose 30 days before delivery. In experiment B (farm 1), consisted of 26 blocks, the animals received two vaccine doses (60 and 30 days before delivery). In experiment C (farm 2), consisted of 22 blocks, the animals received two vaccine doses (60 and 30 days before delivery). In experiments A and B pregnant cows and heifers were used and colostrum and serum from 24-to 36-hour-old calves were collected. In experiment C, pregnant embryo-recipient heifers were used and colostrum and sera from calves at 7, 14, 28 and 42 days of age were collected. Anti-K99 and anti-F41 antibodies were detected by ELISA using purified K99 and F41 fimbrial antigens. In experiment A no difference between treated and control groups was observed for the concentration of anti-K99 and anti-F41 antibodies in colostrum and calf serum. In experiment B a difference (P<0.001) was observed for colostrum of vaccinated females and for serum of their calves. In experiment C, difference between vaccinated and control animals was observed for colostrum and calf serum at 7, 14, 28 (P<0.001 in all cases) and 42 days of age (P= 0.003). The results showed the efficiency of the bacterin to induce detectable humoral immune response.Keywords: calf, enterotoxigenic Escherichia coli, vaccine, diarrhea, K99, F41 (P= 0,003). A bacterina utilizada foi eficiente para a indução de resposta imune humoral detectável. diarréia, Escherichia coli enterotoxigênica, K99, F41, vacina RESUMO Produziu-se uma bacterina de Escherichia coli enterotoxigênica (ETEC) contendo as fímbrias K99 e F41 e avaliaram-se a capacidade de indução de anticorpos anti-K99 e anti F-41 no colostro de vacas vacinadas e no soro de bezerros e a persistência dos anticorpos nos neonatos. Três experimentos foram realizados em duas fazendas comerciais. Os animais foram aleatoriamente alocados em blocos, de duas fêmeas prenhes (uma vacinada e outra controle) e seus respectivos bezerros. No experimento A (fazenda

Diarreia em bezerros: etiologia, tratamento e fatores imunológicos / Diarrhea in calves: etiology, treatment and immunological factors

“…Outro estudo efetuado por Figueiredo et al, (2004) também demostrou eficácia na resposta imune de vacas vacinadas contra as fímbrias K99 e F41 da Escherichia coli enterotoxigênica (ETEC) e a transferência da imunidade passiva através da colostragem. Apesar de ter sido identificada a eficácia da vacinação e a produção de imunoglobulina pelas matrizes, é importante observar o momento e a forma do fornecimento do colostro aos bezerros, pois apenas um colostro de boa qualidade não é fator determinante para uma adequada transferência de imunidade passiva (NEIVA et al, 2015).…”

Kolostrum almış buzağılarda bağışıklığın, büyüme, hastalık insidansı ve yaşama gücü üzerine etkisi

“…Neonatal dönem, doğumla başlayıp 28. güne kadar devam eden ve buzağı kayıplarının en fazla olduğu dönemdir (4). Güç -prematüre doğum, hipotermi, diare ve septisemi bu dönemde en fazla mortaliteye neden olan problemlerdir (8,10). Neonatal dönem sonrası ise (6 aylığa kadar) solunum sistemi hastalıkları mortalitenin en önemli nedeni olmaktadır.…”