Characterisation of undigested components throughout the gastrointestinal tract of broiler chickens fed either a wheat- or maize-based diet

This study was to characterise the undigested nutrients present along the gastrointestinal tract of birds offered common wheat- or maize-based diets, with the goal of optimising utilisation of enzymes to enhance digestive efficiency. Wheat- and maize-based diets were offered to 240 mixed-sex broilers (10 birds/pen; n = 12) from 1 to 35 d post–hatch. Digestibility of dry matter, starch, crude protein and non-starch polysaccharides (NSP) were measured in the crop, gizzard, duodenum, jejunum, ileum, caeca and excreta at d 12 and 35 post–hatch. Analysis of nutrient levels in the excreta presented that more than 30% of nutrients provided in the feed was wasted, irrespective of wheat or maize diet type. On average, 92 g/kg crude protein, 92 g/kg insoluble NSP and 14 g/kg oligosaccharides were not utilised by birds at d 12 post–hatch. The quantity of water-insoluble NSP in the small intestine at d 12 was lower in birds offered the wheat-based diet compared to those fed the maize-based diet (P