PSI-B-28 Breed effect on weight gain of broilers

Abstract Poultry production as an aspect of livestock production is important to the biological needs, economic and social development of the people in any nation. Broiler birds are specifically bred for rapid growth to attain mature body size within 7–10 weeks depending on the strain, sex and management. This study was carried out in the humid tropics of Southwestern Nigeria. The experimental units were derived from four commercial broiler breeds namely Arbor Acre, Cobb, Marshall and Ross. Each breed had 76 chicks totaling 304 across the four breeds. On arrival, each chick was tagged by breed and identification number, and the initial weight of the chicks were recorded. Each of the breeds were thereafter randomly selected and randomly assigned to four experimental plots as replicates of the same treatment. The broiler birds were reared for 10 weeks and their weight taken and recorded at weekly intervals. All statistical analyses were conducted using boxplot, descriptive statistic and general linear models of Minitab® 16. After exploratory analysis to check for normality and outliers, a total of 217 birds were used in the final analyses. Except for the Marshall breed that had a highly significantly (P < 0.01) lower weight at hatching, other breeds had fairly similar weight (Table 1). However, there was no statistical (P > 0.05) difference in mean initial weight across the four replicates. While breed alone accounted for 37.81% of the total variation in initial weight, it only accounted for 30.07% of the difference in weight gain. The effect of breed on weight gain was only significant (P < 0.01) in Marshall, while the other three breeds were not statistically different (P >0.05). It can be deduced from this study that performance in terms of weight gain of most of the commercially available breeds in Nigeria are similar with the exception of Marshall.