RESUMO
A study was carried out to evaluate the effect of broiler breeder age on the development of the digestive tract of embryos and chicks. Fertilized eggs Cobb from 30 and 60 week-old broiler breeder was utilized in this experiment. The results showed that eggs from older (60 weeks of age) broiler breeders were heavier (p = 0.001) than those from younger (30 weeks of age) broiler breeder. In addition, older broiler breeder had larger (p = 0.001) embryos showing a higher yolk sac (p = 0.001) and higher gastrointestinal tract relative weight (p = 0.007) than those from younger broiler breeder. The activities of pancreatic lipase and trypsin enzymes were also higher in embryos from older broiler breeder than those from younger broiler breeder (p = 0.001 and p = 0.002, respectively). Nevertheless, at the seven-day-old chick, no difference was observed in relative weight of gastrointestinal tract or pancreatic lipase and trypsin activities between older and younger broiler breeder age. However chicks from older broiler breeder were heavier than those from younger broiler breeder (p = 0.005). These data suggest that broiler breeder age is important on grower and on the development of the gastrointestinal tract and pancreatic lipase and trypsin activities of embryo. However after one week of hatching the morphophysiological difference disappear.
RESUMO
A study was carried out to evaluate the effect of broiler breeder age on the development of the digestive tract of embryos and chicks. Fertilized eggs Cobb from 30 and 60 week-old broiler breeder was utilized in this experiment. The results showed that eggs from older (60 weeks of age) broiler breeders were heavier (p = 0.001) than those from younger (30 weeks of age) broiler breeder. In addition, older broiler breeder had larger (p = 0.001) embryos showing a higher yolk sac (p = 0.001) and higher gastrointestinal tract relative weight (p = 0.007) than those from younger broiler breeder. The activities of pancreatic lipase and trypsin enzymes were also higher in embryos from older broiler breeder than those from younger broiler breeder (p = 0.001 and p = 0.002, respectively). Nevertheless, at the seven-day-old chick, no difference was observed in relative weight of gastrointestinal tract or pancreatic lipase and trypsin activities between older and younger broiler breeder age. However chicks from older broiler breeder were heavier than those from younger broiler breeder (p = 0.005). These data suggest that broiler breeder age is important on grower and on the development of the gastrointestinal tract and pancreatic lipase and trypsin activities of embryo. However after one week of hatching the morphophysiological difference disappear.
RESUMO
This investigation was carried out in order to study the influence of glutamine supplementation in the ration on performance and on the intestinal structure development of broiler chickens. Three hundred and twenty day-old broiler chickens were used in a completely randomized experiment with two treatments and four repetitions, being T1 supplemented with 1% L-glutamine and T2 - control (not supplemented). The performance was evaluated (feed intake, body weight gain and feed conversion) at 7, 21 and 49 days of age. At the same ages birds were sacrificed and samples from different parts of the intestine were collected (duodenum, jejunum and ileum) to be submitted to morphometric studies under light microscopy using an image analysis system (Video Plan). The variables studied were villous height, crypt depth and villous:crypt ratio. It was demonstrated that 1% glutamine supplementation in the ration did not influence the broiler chicken performance (P>0.05) during the different phases of growth; however, glutamine changes the villous height (P 0.01), crypt depth and villous:crypt ratio in the duodenum, as well as the villous height in the ileum at seven days of age.
Investigou-se o efeito da suplementação de glutamina na dieta sobre o consumo de ração, ganho de peso e conversão alimentar e sobre a estrutura da mucosa intestinal de frangos. Foram utilizados 320 pintos de corte machos distribuídos em um delineamento inteiramente ao acaso com dois tratamentos e quatro repetições, sendo T1 suplementado com 1% de L-glutamina na dieta e T2 controle. Os índices de desempenho foram analisados aos 7, 21 e 49 dias de idade das aves. Aos 7 e 14 dias de idade oito aves foram sacrificadas para colheita de fragmentos de cada porção do intestino delgado para avaliação da morfometria intestinal em microscopia de luz em sistema analisador de imagens "Video Plan". As variáveis estudadas foram altura dos vilos, profundidade de cripta e relação vilo: cripta. A adição de 1% de glutamina à dieta de frangos não influenciou (P>0,05) o seu desempenho zootécnico. Entretanto, 1% de glutamina na ração foi capaz de alterar (P 0,01) a altura do vilo, a profundidade de cripta e a relação vilo:cripta no duodeno, bem como a altura de vilo do íleo de frangos no sétimo dia de idade.