Effects of high fiber ingredients on the performance, metabolizable energy and fiber digestibility of broiler and layer chicks

An experiment was conducted to evaluate the effects of feeding various fiber contents on the performance of chickens bred for egg or meat production from 1 to 21d of age. The lower fiber diet was based on a traditional corn-soybean meal (SBM) diet and the higher fiber diet was formulated by the addition of 60g/kg of both dried distillers grains with solubles (DDGS) and wheat bran in the first period of feeding and 80g/kg of both DDGS and wheat bran in the second period of feeding to the corn-SBM base. The diets were isocaloric and were formulated to meet or exceed NRC requirements. Two lines of male chicks, Ross 308 broilers and Hy-Line W36 layers, were randomly assigned to cages with 11 replicates of 8 chicks for each of the 4 treatments. The evaluation criteria consisted of average daily gain (ADG), average daily feed intake (ADFI), feed efficiency (FE), nitrogen corrected apparent metabolizable energy (AMEn) and neutral detergent fiber (aNDF) digestibility. The higher dietary fiber diet significantly reduced broiler ADG (P≤0.01) for the 1–12d and 1–21d periods but had no effect on layer chick ADG, resulting in a significant interaction. Increasing dietary fiber did not have significant effects on ADFI for the 1–12d and 1–21d periods. Neutral detergent fiber digestibility was higher in layer chicks than broiler chicks regardless of the diet (P≤0.01), and higher dietary fiber concentration resulted in increased ileal (P≤0.01) and total (P≤0.02) aNDF digestibility, across both lines. Apparent metabolizable energy was not different (P=0.96) between lines or dietary fiber content. These results suggest that layer chicks are able to better utilize feed ingredients rich in fiber content compared to broiler chicks, possibly due to decreased ADFI and increased fiber utilization.