Response of broiler chickens to different dietary crude protein and feeding regimens

Abstract

Five isocaloric (3200kcal/kg) diets were used in an experiment designed to investigate the effects of dietary crude protein (CP) and feeding regimens on broiler performance. Day-old broilers were randomly distributed into four groups using a completely randomized design. Each group was replicated three times with ten broiler chicks per replicate. The experiment lasted for eight weeks. Broilers in group 1 received 23% CP from 0 to 3 weeks, 20% CP from 3 to 6 weeks and 18% CP from 6 to 8 weeks, while broilers in group 2 received 23% CP between 0 and 6 weeks and 18% CP between 6 and 8 weeks. Besides, broilers in group 3 were fed 23% CP from 0 to 4 weeks and 16% CP from 4 to 8 weeks, whereas group 4 was given 18% CP from 0 to weeks. Water was supplied ad libitum for broilers in the different dietary groups. A metabolic trial was carried out on the third week of the experiment using a total collection method. Proximate analyses of diets and faecal samples were performed according to the methods outlined by the Association Of the Official Analytical Chemists. Results at market age showed that broiler performance with respect to feed intake, weight gain, feed to gain ratio and water intake were not significantly influenced by CP regimens (p>0.05). Furthermore, CP regimens did not significantly influence broilers liveability (p>0.05). Protein retention, fat utilization and available fiber were not significantly influenced among treatments (p> 0.05). Economic data showed that cost to benefit ratio of producing broilers was comparable among broilers for all CP regimens used in this trial (p>0.05). It was concluded that a single diet of 18% CP and 3200kcal/kg metabolizable energy would be most suitable and convenient for farmers who are engaged in on-farm feed production for broilers as compared with the standard feeding regimens of broiler starter and broiler finisher diets.