Productive and physiological performance of two local strains of chickens at early period of laying as affected by enzyme supplementation under summer conditions of Egypt 2- avizyme1500 enzyme

A total of 360 pullets at 22 weeks of age from two local strains (Mandarah and Dokki-4) 180 birds each, were used to study the effect of dietary Avizyme 1500 supplementation on productive and physiological performance of two local strains of chickens during early period of laying under summer conditions. The experiment continued for 12 weeks from 22 up to 34 weeks of age. The birds were randomly distributed into six treatments each of two replicates (fifteen of each strain). Two corn-Soybean basal diets formulated to provide normal ME (2,890 cal/kg) or low ME (2,805 kcal/kg) were combined with or without three levels of Avizyme 1500 supplementation (0,1 and 2 g/kg diet).The experimental treatments were in 2(Stains) x 2 (ME levels) x 3 (Avizyme 1500 levels) factorial design. Egg production, egg quality, plasma Ca, P, cholesterol, total protein, albumin and globulin were studied. The results indicated that: Enzyme supplementation had a significant positive effect on feed conversion and body weight gain. Hens- fed 2,890 kcal/kg diets supplemented with Avizyme 1500 (1 or 2 g/kg of diet) gave higher body weight gain (BWG) and significantly improved feed conversion (FC) as compared with the hens fed 2,890 or 2,805 kcal/kg diets without enzyme supplementation. - Enzyme supplementation significantly affected egg production (EP) in each strain. Mandarah hens laid eggs of greater weight when fed normal ME diets compared with eggs from the Dokki-4, which were heavier from hens on the low ME diet. Hens fed 2,890 kcal/kg diets supplemented with Avizyme 1500 (1 or 2 g/kg of diet), showed significant (P¡Ü 0.05) increase in egg weight, egg mass and an improvement in some egg quality parameters in Mandarah strain compared to Dokki-4 strain. However, hens fed 2,890 kcal/kg diets performed better than those fed 2,805 kcal/kg diets for egg production and feed conversion. - Enzyme supplementation had a significant positive effect on nitrogen, calcium and phosphorus retention but no effect was obtained on AME or digesta viscosity. - Hens of the two strains, fed 2,890 kcal/kg diets supplemented with Avizyme 1500 (1 or 2 g/kg of diet), showed an increase in plasma calcium, phosphorus, total protein, albumin and globulin, but there was a decrease in plasma cholesterol as compared with other groups. In conclusion, Mandarah and Dokki-4 laying hens fed low ME diet, whether supplemented or not with Avizyme 1500 performed less efficiency for egg production and feed conversion than those fed the 2,890 kcal/kg diets supplemented with Avizyme 1500.Additionally, it would appear that Mandarah laying hens had better performance than Dokki-4 laying hens irrespective to energy or enzyme levels