Effect of Dietary Crude Fibre Levels and Enzyme Supplementation on Balance of Nutrients in Broilers

The effect of dietary crude fibre levels (5, 7, 9 and 11%) and enzyme supplementation on dry matter metabolizability, nitrogen, calcium and phosphorus retention and energy metabolizability were studied. Dry matter metabolizability ranged from 59.60±0.59 (11% CF, unsupplemented) to 64.55±0.59 (7% CF, enzyme supplemented). The DM metabolizability was significantly (P<0.05) low in higher CF levels. The nitrogen retention also ranged from 57.71±0.50 (11% CF, unsupplemented) to 62.63±0.53 (9% CF, enzyme supplemented), the differences being statistically significant. Calcium retention was not significantly affected due to crude fibre levels. Enzyme supplementation also did not affect calcium retention significantly. Phosphorus retention ranged from 53.16±0.41(11% CF, unsupplemented group) to 58.80±0.37 (9% CF, enzyme supplemented). The results indicated significantly higher (P<0.05) phosphorus retention due to enzyme supplementation. Nitrogen corrected metabolizable energy (Kcal/kg) was significantly higher in T₇ (9% CF, enzyme supplemented group) and T₈ than their counterparts T₃ and T₄. In T₅ and T₆ there was non-significant improvement as compared to unsupplemented groups T₁and T₂. Gross energy metabolizability (%) also showed same trend. The results indicated significant decrease (P<0.05) in gross energy metabolizability with increasing crude fibre levels and enzyme supplementation resulted significant improvement.