Effect of the duration of prefeeding on amino acid digestibility of wheat distillers dried grains with solubles in broiler chicken

The objective of this study was to determine the effect of the duration of prefeeding on prececal amino acid (AA) digestibility of wheat distillers dried grains with solubles (DDGS) in broilers. The experimental diets with DDGS at levels of 0, 10, and 20% were offered ad libitum for 7, 5, and 3 d, starting on 14, 16, and 18 d of age. Titanium dioxide was used as an indigestible marker. Six pens of 10 birds were allocated to each treatment. Digesta was sampled on a pen basis from the distal two-thirds of the intestine section between Meckel's diverticulum and 2 cm anterior to the ileo-ceca-colonic junction. Ingested and digested amounts of AA were determined for each pen. Digestibility of AA in the diets was not significantly affected by the duration of prefeeding but was significantly reduced by inclusion of DDGS. Digestibility of AA in DDGS was determined by using a linear regression approach. The digestibility of AA in DDGS ranged from 76% (Arg, 5 d of feeding) to 33% (Asp, 3 d of feeding). There was no significant effect of prefeeding time on AA digestibility of DDGS. Lysine digestibility of DDGS was 72%. The mean digestibility of the AA Arg, Cys, Ile, Leu, Lys, Met, Phe, Thr, and Val of DDGS across the 3 prefeeding times was 66%. This study gave evidence that 3 d of prefeeding a diet is sufficient in studying prececal AA digestibility in broilers when low-digestible feeds are used.