Responses of semi-scavenging F1 crossbred (Rhode Island Red male x Fayoumi female) grower and pre-layer chickens to diets of different nutrient density formulated with locally available feed ingredients

Two experiments were conducted to investigate the birds' responses to diets of varying nutrient concentrations, one with 126 eight-week old Fsub(1) crossbred (Rhode Island Red male x Fayoumi female) birds up to 20 weeks of age (growing stage) and another with ninety 20-week-old birds up to 22 weeks (pre-layer stage) under semi-scavenging condition in the poultry farm. Dietary treatments consisted of an arrangement of three diets that contained 14% crude protein (CP) and 2550kcal metabolizable energy (ME)/kg (low nutrient density ; LND), 15% CP and 2750kcal ME/kg (moderate nutrient density ; MND) and 16% CP and 2950kcal ME/kg (high nutrient density ; HND). The contents of CP, ME and calcium (Ca) in MND diet were fitted with the requirements calculated in this experiment based on five nutrient specifications in the world. All diets were formulated using locally available conventional feedstuffs and un-conventional feed ingredients employing a free software of computer program for least-cost feed formulation. The responses of grower birds to different diets showed that the highest body weight and live weight gain were achieved by the birds that received HND diet that differed significantly from those of LND diet (p0.05). Uniformity, defined in this study, at 20 weeks of age was significantly highest in birds reared on HND than those of LND and MND groups (p0.01). During the pre-1ayer period, the birds of LND diet group consumed the highest amount of feed that differed significantly from other dietary groups (p0.01). Uniformity at 22 weeks of age in all groups improved but it was still higher in MND and HND diet groups. It may be concluded that it is possible to formulate least-cost poultry diets by incorporating locally available feed ingredients and the responses of birds to HND is most favorable and therefore its nutrient specifications may be followed for formulating diets of semi-scavenging Fsub(1) crossbred (Rhode Island Red male x Fayoumi female) grower and pre-1ayer chickens.