Genetic analysis of layer performances in a selected line of Rhode Island Red chicken

Abstract

The study aimed to estimate genetic parameters of layer performance traits in a selected line of Rhode Island Red (RIR) chicken maintained at this institute. The performance traits were recorded on 433 pedigreed pullet progenies, offsprings of 48 sires and 113 dams; and data were analyzed by least squares analysis of variance. Heritability and correlations were estimated using full-sib correlation method. The least squares means of age at first egg (AFE), body weights (BW20, BW40), egg weights (EW28, EW40) and egg production up to 40 weeks of age (EP40) were estimated. Almost all the traits were significantly affected by sires and hatch, whereas dam within sire could not affect any trait. Birds’ housing weight demonstrated significant regression effect on the above traits. The heritability estimates from sire component of variance ranged from 0.003 to 0.241 in different traits. The heritability estimates from dam component and sire plus dam component ranged from 0.011 to 0.670 and 0.061 to 0.379, respectively. The ranges of genetic and phenotypic correlations among the traits were 0.130 to 0.918 and 0.015 to 0.542, respectively. The varied direction of correlations revealed that selection for earlier age at first egg would favour moderately lower body weights and egg production. Again selection for heavier EW28 would favour late AFE and lower egg production. Present findings would serve as the pre-requisites for chalking out the breeding strategies for genetic improvement of RIR chicken.