| Popis: |
A total of 90day – old Hypeco broiler chicks were used in a choice-feeding trial to investigate whether meat-type chicken could select adequate nutrients that would support fast growth rate from a choice of imbalanced diet and feed ingredients. Three diets were used: a control diet (diet A= 200g/kg CP, 3031 kcal/kg ME) and two test diets; a low protein, high-energy diet (diet B=166g/kgCP, 3021 kcal/kg ME) and a low-protein, low-energy diet (diet C=168g/kgCP, 2838 kcal/kg ME). The diets were fed singly. The test diets were also used in a choice-feeding with ground maize and soya-bean meal (SBM). The study lasted for 5weeks and the response criteria included growth performance, carcass and organ characteristics, and economics of production. Weight gain and feed conversion ratio were significantly (P < 0.01) and (P < 0.001 respectively) influenced. Birds on the control diets had the highest weight gain and best feed conversion ratio. Birds on the low-protein, high-energy diet had performances not significantly (P > 0.05) lower than the control. The low-protein, low-energy diet depressed performance. Feeding the imbalanced diets (diets B and C) singly produced better performances than feeding them with a choice of dietary ingredients. Birds exhibited selection potentials by selecting the ground maize and SBM to compensate for deficiencies in the imbalanced diets but not at a level adequate enough to improve performances. Only the relative chest weight was significantly (P < 0.05) influenced amongst the carcass and organ weights measured. It decreased with decreasing feed quality. Economics of production showed that low quality and cheaper priced feeds do not necessarily give higher income and profit. The benefits of feeding single balanced diets and the possibility of decreasing the protein content of broiler finisher diets without compromising profits were revealed. It was suggested that broiler chicken appeared to select nutrients for maximize economic performance and that feed quality control should be enforced. |
