Subsequent growth performance and digestive physiology of broilers fed on starter diets containing spray-dried porcine plasma as a substitute for meat meal

Abstract

A 4 × 2 factorial experiment was conducted to investigate the effect of inclusion of spray-dried porcine plasma (SdPP), in lieu of meat meal, in the starter diet on performance and digestive physiology of broiler chickens between hatch and 35 d of age. Four levels of SdPP (0, 5, 10 or 20 g/kg) were included in the starter diets in lieu of meat meal on either wheat- or maize-based diets. Over the first 10 d, and throughout the 35-d experimental period, birds gained more body weight with increasing concentrations of SdPP regardless to the type of grain used. Inclusion of SdPP in the starter diet markedly improved feed per gain in the starter phase and across the 35-d study. There was no significant effect of the type of grain and its interaction with SdPP on the body weight gain and feed per gain for the two assessed periods. At d 10, the relative weight of the gizzard+proventriculus, spleen and liver increased with increasing concentrations of SdPP. At 24 d of age, the grain and SdPP inclusion significantly interacted, depressing the weight of bursa and spleen in birds that received the highest concentration of SdPP in the maize-based diet. Birds fed on the maize-based diets had higher relative weight of pancreas than those on the wheat-based diets. Increasing concentrations of SdPP in the starter diet improved the activities of maltase, sucrase and alkaline phosphatase at 24 d of age. The interaction of grain and SdPP concentration was significant for sucrase activity in birds on the wheat-based diets. Chickens on maize-based diets had higher alkaline phosphatase and maltase activities than those on wheat-based diets. Chicks that were offered SdPP-containing starter diets had longer villi, deeper crypts and lower villi/crypt than the control at 24 d of age regardless of the grain type used. Furthermore, longer villi and larger villi/crypt were found in chicken groups fed on wheat-based diets than those on maize-based diets. Chickens on maize-based diets had higher dressing percentage and relative breast weight than those on wheat-based diets at 35 d of age. It can be concluded that supplementation of starter diets with SdPP would be beneficial to the long-term growth of broiler chickens. The effect of the basal grain used in the diet is minimal.