No abstract

Present study was conducted with the aim of replacing dietary crude protein (CP) in poultry diet with synthetic essential amino acids and to determine its effect on growth performance, slaughter data and nutrient digestibility in broilers. Five (A, B, C, D and E) iso-caloric & iso-nitrogenous (ME 2850/2950 Kcal/kg; CP 20%/18%) starter and finisher diets were formulated respectively. In both phase diet A was standard diet, in remaining starter/finisher diets (B, C, D and E) CP level was reduced (19/17, 18/16, 17/15 and 16/14) and make them iso-nitrogenous by supplementation of synthetic amino acids. Result showed no significant (P>0.05) effect of replacing CP with synthetic amino acids on all parameters of growth performance of broilers except on feed intake during starter phase. Best FCR during starter (1.33) and finisher (1.67) phase was found in broilers fed on diet B. Similarly, highest (P>0.05) dressing percentage with lowest (P>0.05) abdominal fat was observed in birds fed on diet B while highest (P>0.05) breast meat yield was found in control group. No significant (P>0.05) effect of replacing CP with amino acids was found on nutrient digestibility in both phase, highest digestibility was found in group C (75.50%) and E (79.84%) during starter and finisher phase, respectively. It is concluded that CP of boiler diet can be replaced by synthetic amino acids up to 17 and 15% in start and finisher diet, respectively without compromising the growth performance of broilers.

The aim of the present study was to evaluate the role of zinc supplementation on growth performance, carcass traits and immune response of broilers fed antibiotic free diet. Four hundred day old broiler chicks were randomly divided into five treatments with four replicates (twenty birds/treatments). Experimental group include ZN0: control group with basic diet, ZN40: basic diet with supplemented 40 mg/kg zinc, ZN80: basic diet with supplemented 80 mg/kg zinc, ZN120: basic diet with supplemented 120 mg/kg zinc and ZN160: basic diet with supplemented 160 mg/kg zinc. The experimental diets were formulated according to the NRC standards. Results indicated that there was decline in weight gain, feed intake and FCR with increasing level of zinc above 80 mg/kg in diet. Weight gain and feed intake was higher (P<0.05) in the ZN80, whereas lower FCR as compared to other treatments. Dressing percentage was higher (P<0.05) in ZN80. ZN80 costs lower price for production per kg as compared to rest of treatments. It was concluded that supplementation of zinc 80 mg/kg above NRC recommended level improved growth and economical with lower FCR during antibody free rearing of broiler birds.