Resumo
Campylobacter coli is an important species involved in human cases of enteritis, and chickens are carriers of the pathogen mainly in developing country. The current study aimed to evaluate the transmission of C. coli and its pathogenic effects in chicken embryos. Breeder hens were inoculated intra-esophageally with C. coli isolated from chickens, and their eggs and embryos were analyzed for the presence of bacteria using real-time PCR and plate culture. The viability of embryos was verified. In parallel, SPF eggs were inoculated with C. coli in the air sac; after incubation, the embryos were submitted to the same analysis as the embryos from breeder hens. In embryos and fertile eggs from breeder hens, the bacterium was only identified by molecular methods; in the SPF eggs, however, the bacterium was detected by both techniques. The results showed no relationship between embryo mortality and positivity for C. coli in the embryos from breeder hens. However, the presence of bacteria is a cause of precocious mortality for SPF embryos. This study revealed that although the vertical transmission is a possible event, the bacteria can not grow in embryonic field samples.
Resumo
Campylobacter sp is a microaerophilic, thermotolerating Gram negative bacterium, known to be one of the main causes of food-borne human infections. Among the foods that carry these microorganisms, the chicken is outstanding. In Brazil, a large chicken exporting country, few researches are conducted about their prevalence in breeder hens and the transmission through eggs. The aim of this research was to verify the presence of Campylobacter sp in the shells and within the eggs from positive cloacal swab breeder hens. Microbiological analyses were made on cloacal swabs of 140 weighed breeder hens. The positive breeder hens were set aside and in a total of 244 of their eggs, Campylobacter sp was present in macerated shells and yolk contents during 7 weeks. Out of the 140 researched breeder hens, 25 (17.8%) were positive from cloacal swabs, however the eggs were not positive. The physiological characteristics of the birds, their eggs and Campylobacter sp favor the bacterium entering and surviving in the eggs, but in this study, no positive result was found in macerated shells or in the yolks, indicating that vertical transmission is probably an unusual event.
Campylobacter sp é reconhecida como uma das principais causas de gastrenterite humana de origem alimentar. Dentre os alimentos veiculadores desses microrganismos, a carne de frango tem sido a mais implicada. Os estudos existentes sobre a transmissão vertical da Campylobacter são escassos e não conclusivos. O objetivo desse estudo foi verificar a presença de Campylobacter sp na casca e interior de ovos de matrizes positivas em swabs cloacais e a possibilidade de transmissão vertical. Foram analisados swabs cloacais de 140 matrizes pesadas e seus ovos colhidos para análise durante 7 semanas consecutivas. Dos 244 ovos colhidos, 129 foram fumigados e 115 analisados sem tratamento. Foram analisados o macerado da casca e a gema. Das 140 matrizes pesquisadas, 25 (17,8%) foram positivas em swabs cloacais. Não houve positividade em nenhuma das amostras de ovos, independente da fumigação ou período de coleta. Apesar das características fisiológicas das matrizes, dos ovos e da Campylobacter sp serem favoráveis à entrada e sobrevivência da bactéria nos ovos, nesse estudo, nenhuma positividade foi encontrada, tanto no macerado da casca quanto na gema dos ovos, indicando que a transmissão vertical é possivelmente um evento raro.