THE EFFICIENCY OF PROTEIN UTILIZATION IN DIFFERENT BROILER STRAINS

Abstract

The objective of this work was to study the protein utilization and protein turnover of different broiler strains and was carried out in completely randomized design. One hundred and forty four sexed doc from each strain (Cobb =A, Ingham = B and Steggels = C) were divided into a factorial arrangement (three dietary protein, two sexes and three strains). Two regimens of composite mixes of a summit and dilution diet and a free choice between these two diets. Diets were changed weekly, with notional crude protein levels at one day-old of 240g/kg for all chickens, and at 42 days of age of 120 or 180 g/kg in the low and high protein. Protein utilization efficiency (PRE) was measured from 39-42 d of age. PRE increased with the increasing of dietary protein in strains A and C and had much higher response than in strain B. The moisture: protein ratios were 2.51, 2.65 and 2.58 in strains A, B and C, indicating strain B contained higher moisture and body fat and less protein. Involvement of genetic controls as the selection effect seems to increase the capacity of chickens in improving nutrient utilization. Keywords: Summit Dilution, Strains, Protein