author(s)
Sreedhara JN, Jayanaik, Jagjiwan Ram, Malathi V, Gopinath CR, Prabhu TM and Suguna Rao

abstract
A biological trial was conducted to study the effect of phytase supplementation on fertility, hatchability and egg quality traits in Swarnadhara breeders reared from 29 to 48 weeks at the Department of Poultry Science, Veterinary College, Hebbal, Bengaluru. The trial had total 450 birds with 5 treatments and three replicates per treatment, each having 30 birds (90 birds per treatment). Control diet (T1) was formulated according to ICAR (2013) nutrient requirements and the groups T2 to T5 were formulated with changed non-phytate phosphorus levels so as to contain 0.12% in T2, 0.18% in T3, 0.12% NPP with 500 IU/kg phytase in T4 and 0.18% NPP with 500 IU/kg phytase in T5. Fertility, hatchability, albumen index, haugh unit score and yolk index are not significantly (P>0.05) affected by phytase supplementation. The addition of phytase to the diets having 0.12 % NPP significantly (P<0.05) increased the egg weight to the level on par with the control group in phase I, III and IV. NPP level of 0.12% with phytase is optimum for Swarnadhara breeders to maintain egg quality traits. There was no additional advantage, however, of increasing the NPP concentration above 0.12% or adding phytase above this level in Swarnadhara breeders.