Genetic studies on egg production traits in IWN and IWP strains of White Leghorn chicken

Abstract

The genetic study was conducted using data generated on 669 and 718 birds of IWN and IWP strains, respectively at the Poultry Complex, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand. The traits measured were age at first egg (AFE), egg weight at 24 (EW24), 28 (EW28), 32 (EW32), 36 (EW36) and 40 weeks of age (EW40), total egg number produced up to 40 weeks of age (TEN40) and total egg mass produced up to 40 weeks of age (TEM40).The heritability estimates obtained for AFE was 0.458±0.13 and 0.179±0.09 in IWN and IWP strains, respectively. The heritability estimates for egg weight at 40 week of age was 0.367±0.12 in IWN strain and 0.100±0.07 in IWP strain, respectively. The heritability estimate for TEN40 was 0.290±0.11 and 0.122±0.07 in IWN and IWP strains, respectively. The heritability estimate for TEM40 was 0.241±0.10 and 0.074±0.07 in IWN and IWP strains, respectively. Genetic and phenotypic correlations of age at first egg with total egg number produced up to 40 weeks of age were found to be negative and high in magnitude. Negative genetic correlations were observed between age at first egg and egg weights at different ages in IWN strain. However, the positive genetic correlations were found in IWP strain in increasing trend with advancement in age.