Abstract:
The influence of feed enzymes, viz., cellulose or protease supplemented at levels of 0.06 or 0.02 per cent respectively, on nutrient availability and on production performance was evaluated in a standard and a less dense layer ration using one hundred IWN strain of Single Comb White Leghorn pullets of 20 weeks of age for an experimental period of 20 weeks. A standard layer ration was formulated as per BIS, 1993. With 18 per cent crude protein and 2600 kcal of ME per kg of feed and a less dense layer ration with 16 per cent crude protein and 2500 kcal of ME per kg of feed. A few feed ingredients such as jowar, deoiled rice bran, wheat bran and undecorticated sunflower cake were included in both rations. A numerical improvement was noticed in percentage hen – housed and hen – day egg production in enzyme treated groups, however, the increase in egg number was not statistically significant. Egg weight and egg quality characteristics such as yolk and albumen indexes, Haugh unit scores and shell thickness were not affected by enzyme treatment. A positive influence of the enzymes on feed intake by birds was observed in as much as the feed intake with less dense ration supplemented with enzymes was not different statistically from those with the control ration. There was positive enzyme effect on feed per egg in treatment groups on standard layer ration with both enzymes and in less dense ration with protease. Feed efficiency for egg production (egg number) was significantly higher in birds fed standard layer ration with cellulose and protease than those on other treatments (P < 0.05). There was improvement in digestibility of crude protein and utilisation of energy, even though the differences noted were not significant statistically. The enzyme treatment of rations reduced moisture content of excreta. The microbial load on the surface of eggs was comparatively low in enzyme treated groups. The intestinal viscosity was reduced with enzyme addition in feed mixtures. The cost – benefit analysis indicated that but for the prohibitive enzyme cost, the feed enzymes were nutritionally beneficial. Based on the present investigation it is concluded that there is tremendous scope for enzymes in feed industry, especially at the present context of feed shortages and the emphasis for the utilisation of alternative feed resources in poultry rations.
