Uso de antibiótico associado a vacinação in ovo rendimento de incubação e parâmetros zootécnicos de pintos de corte

Abstract

The use of antibiotics concomitantly with in ovo vaccination has been carried out routinely in industrial hatcheries. However, research on the implications of this procedure is scarce. A large-scale experiment was carried out to evaluate the effects of using the antimicrobial gentamicin associated with Marek's vaccination in ovo on the incubation performance, quality and morphophysiology of newly hatched chicks. Eggs from 35-week-old Cobb® breeders were divided into two treatments, based on whether or not the antibiotic was applied at the time of in ovo vaccination. The study was divided into two experimental phases. In the first phase, analyzes of the quality of hatchable eggs and incubation performance were carried out. In the second phase, the quality and physiological parameters of 1-day-old chicks were evaluated. The hatchability of fertile eggs was not affected by the inclusion of antibiotics in ovo (P>0.05), nor was there any change in embryonic mortality (P>0.05). Chicks that received antibiotics had higher quality variables such as weight, YFBM and length (P<0.05) when compared to chicks that did not receive antibiotics. However, the navel score showed no significant difference. In relation to the weight of the organs, the embryos that received the antimicrobial had higher (P<0.05) absolute weights of the heart, liver and lung. Glucose, lactate and uric acid were the biochemical parameters analyzed and the results suggest that chicks from eggs inoculated with antibiotics mobilize less muscle protein during the hatching process. It was concluded that the use of the antibiotic gentamicin associated with in ovo vaccination at a dose of 0.20mg/egg does not alter incubation performance and produces better quality day-old chicks. In-depth studies on the use of antibiotics in ovo must be carried out during the raising and slaughtering of birds to elucidate the zootechnical and food safety impacts of this practice.