Nutrient utilization in sheep fed sorghum stover-based diets supplemented with cellulase and xylanase.

摘要

An experiment was conducted on 12 male lambs (6-8 months of age, 20.14+or-1.76 kg body weight) fed sorghum stover as sole roughage source in total mixed ration (TMR) (roughage: concentrate, 50:50) to study the effect of supplementing exogenous fibrolytic enzymes (EFE) comprising of 38400 cellulase and 25600 xylanase IU/g DM(dry matter) stover on nutrient utilization. The required amount of EFE was added to concentrate mixture of TMR diet before blending with chopped stover. The animals were randomly allotted to 2 dietary groups i.e., sorghum stover based TMR and the TMR supplemented with EFE. They were fed with respective diets for a preliminary period of 21 days followed by 7 days collection period. Supplementation of EFE improved the digestibility of organic matter, nitrogen free extract, cell contents, neutral detergent fiber and cellulose in sheep, with no effect on crude fiber and ether extract digestibilities. Though non-significant, crude protein digestibility lowered with EFE supplementation resulting in lower digestible crude protein content of diet. The total digestible nutrient and metabolic energy content improved with EFE supplementation. No effect of EFE supplementation was observed on calcium and phosphorus balances. The lower nitrogen intake with EFE supplementation resulted in lower nitrogen balance, but when expressed as per cent intake, the nitrogen balance did not vary. The results of this study indicated the fibrolytic enzymes supplemented to sorghum stover-based rations at concentration of 38400 IU cellulase and 25600 xylanase IU/g DM stover improved the nutrient digestibility and TDN content.