Requirement of non-phytate phosphorus in broiler breeder diet
S.K. BHANJA*, V.R. REDDY, A.K. PANDA*, S.V. RAMA RAO*
AND R.P. SHARMA*
Department of Livestock Production and Management
College of Veterinary Science
* Project Directorate on Poultry
Rajendranagar, Hyderabad - 500 030
An experiment was conducted to study the laying performance, shell quality, bone mineralisation, hatchability of eggs, performance of progeny (weight at day one and 14d of age, P content in day old chick, leg score and survivability of chicks) of broiler breeders fed different levels of non-phytin phosphorus (NPP). Six levels of NPP (1.2, 1.8, 2.4, 3.0, 3.6 and 4.0g/kg diet) at a constant calcium (Ca) level (30g/kg) in maize-soya-deoiled rice bran based diet were tested. Levels of dicalcium phosphorus, shell grit and deoiled rice bran were adjusted to arrive at the desired levels of NPP and Ca. Each level of NPP was fed with weighed quantity of feed (160g/b/d) to 40 female broiler breeders from 25 to 40 weeks of age housed in individual cages. Each bird was considered as a replicate. Egg production, feed/egg mass, body weight, egg weight, shell weight, shell thickness, egg specific gravity, serum Ca content and tibia breaking strength were not influenced (P > 0.05) by the variation in dietary NPP levels tested. Increasing the dietary levels of NPP did not influence the hatchability of eggs, phosphorus (P) contents both in egg yolk and day old chick, chick body weight at day one and 14d of age, leg score and survivability of chicks up to 14d of age. Maximum response (P <0.01) in shell breaking strength, tibia ash and serum inorganic P contents were observed at NPP levels of 2.09, 2.25 and 3.50g per kg diet, respectively. The retention of Ca increased, while the P retention decreased (P <0.01) with increasing dietary levels of NPP. Though maximum response in shell breaking strength, bone ash and serum inorganic P were observed at NPP higher than 1.2g/kg diet, the broiler breeder performance in terms of egg production, shell quality, hatchability of eggs and progeny performance and their survivability were not influenced by dietary NPP concentrations. It is concluded that broiler breeders maintained in cages do not require more than 1.2g NPP/kg diet with a daily intake of 192mg NPP/b/d.