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

Eunjoo Kim; Natalie K Morgan; Amy F Moss; Lily Li; Peter Ader; Mingan Choct

doi:10.1016/j.aninu.2021.09.011

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

Anim Nutr. 2022 Mar;8(1):153-159. doi: 10.1016/j.aninu.2021.09.011. Epub 2021 Oct 20.

Authors

Eunjoo Kim¹, Natalie K Morgan¹, Amy F Moss¹, Lily Li², Peter Ader³, Mingan Choct¹

Affiliations

¹ School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia.
² BASF, South East Asia, 038987, Singapore.
³ BASF SE, 68623, Lampertheim, Germany.

Abstract

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 < 0.05), with the reverse being true for water-soluble NSP (P < 0.001). On average, 84 g/kg crude protein, 79 g/kg insoluble NSP and 9 g/kg oligosaccharides remained in the excreta at 35 d of age. At this time period, accumulation of feed in the gizzard was noted for birds offered both diets, but was more pronounced in those offered the maize-based diet (P < 0.001). Birds offered the maize-based diet demonstrated improved utilisation of oligosaccharides compared to those fed the wheat-based diet at both d 12 and 35 (P = 0.087 and P = 0.047, respectively). Protein utilisation in the jejunum and ileum was greater in birds offered the wheat-based diet compared to those fed the maize-based diet (P = 0.004 and P < 0.001, respectively). Thus, while both diets supported standard growth performance of birds, the degree and flow of nutrient disappearance along the gastrointestinal tract was influenced by cereal type and bird age.

Keywords: Broiler chicken; Nutrient digestibility; Undigested dietary component.