Fishmeal and maize starch inclusions in sorghum-soybean meal diets generate different responses in growth performance, nutrient utilisation, starch and protein digestive dynamics of broiler chickens

This study comprised a 2 × 2 factorial array of dietary treatments offered to male Ross 308 broiler chicks from 15 to 28 days post-hatch. The dietary treatments consisted of a sorghum-soybean meal diet in which either sorghum was partially substituted by maize starch (200 g/kg) or soybean meal was partially substituted by fishmeal (175 g/kg). Growth performance, nutrient utilisation, digesta retention times in four small intestinal segments, starch and protein (N) digestibility coefficients and disappearance rates (g/bird/day) and starch:protein disappearance rate ratios in four small intestinal segments were determined. The partial substitution of soybean meal by fishmeal had the more profound effects on the parameters assessed as fishmeal inclusions improved weight gain by 12.1% (1260 versus 1124 g/bird, P