Effect of particle size and enzyme supplementation of diets based on dehulled peas on the nutritive value for broiler chickens

The effect of diets based on dehulled peas on live weights, cumulative feed intake, feed conversion ratio and apparent ileal nutrient digestibility was studied in broiler chickens. The diets consisted of 700 g kg−1 of milled or crushed dehulled peas with or without pectinase or α-galactosidase supplementation. The high inclusion level of raw dehulled peas was well tolerated by the chickens. Supplementation with α-galactosidase to the milled diets gave the highest cumulative feed intake whereas no effect was seen for the crushed diets with larger particle size. Pectinase supplementation significantly increased cumulative feed intake on the 10th day for both the milled and the crushed diets, compared to the unsupplemented diets. Live weights and feed conversion ratios were statistically unaffected by the different diets. Dry matter content of ileal digesta was significantly higher for the crushed diets, whereas apparent ileal digestibility of organic matter, starch, crude protein, crude fat and ash was significantly lower for the crushed than the milled diets. Enzyme supplementation had no effect on apparent ileal digestibility. Dietary fibre polysaccharide residue digestibility was low or negative, but the solubility of dietary fibre polysaccharide residues increased with pectinase supplementation.