Genetic characterization of layer germplasm evolved by AICRP on poultry breeding

The study was carried out to evaluate White Leghorn lines (IWH, IWI, IWK and layer control-LC) and to genetically characterize IWH and LC lines for production traits. Body weight at 20 weeks was significantly higher in LC, IWH and IWK lines as compared to IWI. Similarly, body weight at 40 weeks of age was also significantly higher in LC as compared to IWK, IWH and IWI. Among selected lines, it was significantly higher in IWK than that in IWH and IWI. The ASM was significantly lesser in IWH followed by IWI, IWK and LC. Egg weight at 28 weeks was significantly higher in LC followed by IWK, IWI and IWH. However, egg weight at 40 weeks was significantly higher in IWK followed by LC, IWI and IWH. Similarly, egg weight at 52 weeks of age was significantly higher in IWK followed by LC, IWH and IWI. Egg mass at 40 weeks of age was significantly higher in IWH, IWI and IWK as compared to LC. Egg mass at 52 weeks of age was also significantly higher in IWH as compared to IWK, IWI and LC. However, this trait was significantly higher in IWK and IWI as compared to LC. Heritability estimates on sire component of variance were high for all the traits except for ASM (moderate) in IWH while, they were high for all the traits except for body weight at 40 weeks of age (moderate) in LC. The study concluded that despite the continuous selection, these lines differ for many of the production traits and considerable genetic variation exists for many of the traits in IWH and LC, and IWH line could continue to be improved for production traits.