Efeitos das diferentes relações cálcio:fósforo disponível e fitase sobre o desempenho produtivo, qualidade dos ovos e tecido ósseo de poedeiras de ovos de casca marrom

Abstract

Two experiments were conduced to the effect of relationship between calcium and phosphorus available (8/1; 11/1 and 14/1) in diets based on maize and soybean meal. Each experiment used 144 brown egg layer (UFSM V and UFSM P strain) from 28Th to 36Th weeks of age. The evaluated parameters had been body weight, fed intake, fed efficiency, egg production, albumen height, eggs mass, specific gravity of eggs, Haugh Unit and percentage of calcium, phosphorus and ash of the tibia. Each experiment was in a factorial design 3x2, with tree relationship between calcium and phosphorus available (8/1; 11/1 and 14/1) and two phytase levels (0 and 300FTU/kg), with six replicates with four layers hens each. The external quality of eggs based on specific gravity, were positively affected (P<0.026), by interaction between calcium and phosphorus available relationship and phytase, in the last studied period, of UFSM-P strain, when the specific gravity improved with the increase of the calcium and phosphorus available relations and phytase. The productive parameters and the internal quality of eggs were not affected by the studied factors, however, the bone quality, based on ash, calcium and phosphorus in the tibias, were lower when dietary calcium and phytase levels were decreased.