Authors:O. Olowofeso and M. A. Adeleke
Egypt. Poult. Sci. Vol (32) (II): (259-262)
Abstract
Coefficient of repeatability (r) for numbers of eggs laid by Harco Black and Bovan Nera layer strains in the first two phases of laying were computed using whole eggs produced between 20 and 28 weeks of age (Phase I) and 29 and 36 weeks of age (Phase II) in both strains. In phase I, mean numbers of eggs laid by Bovan Nera and Harco Black were 98.00±1.97 and 106.00±2.05, and in phase II, it was 110.88±2.28 and 114.38±1.63 for Bovan Nera and Harco Black, respectively. Using the weekly results in both phases and for each layer strain, coefficient of repeatability estimated was 0.37 for Harco Black and 0.50 for Bovan Nera, indicating that ‘r’ for this economic trait (numbers of eggs laid) ranged from moderate to a high value in Harco Black and Bovan Nera layer strains, respectively. The results also suggest that while this trait of importance was moderately repeatable in Harco Black, it was highly repeatable in Bovan Nera strain. Results of this trial therefore show that coefficient of repeatability for a given trait is not fixed and varies from population to population.