Influence of dwarf gene on egg production of ‘Narmada-XL’ egg layer, dwarf and normal Broiler pullets
Indian Journal of Animal Science
Jan 1, 1983
Core Idea
This 1983 companion study looks at how the dw (dwarf) gene affects egg production and egg quality in three pullet genotypes, 'Narmada-XL', dwarf broilers, and normal broilers, finding that despite laying fewer defective eggs, dwarf-gene pullets actually produced significantly more eggs overall than their normal-bodied counterparts.
Audience
Practising veterinarians, veterinary students, Researchers.
Key Takeaways
01
Dwarf-Gene Pullets Outperformed on Egg Production
'Narmada-XL' pullets laid 79.6 eggs on average during 21-40 weeks of age, notably higher than dwarf broiler (66.2) and normal broiler (64.7) pullets, a statistically significant genotype effect. This challenges the assumption that the dw gene is purely a production drawback, since well-managed dwarf genetics actually laid more eggs here.
02
Defective Egg Rates Were Lowest in Dwarf Genotypes
Normal broiler pullets produced notably more defective eggs (5.25%) than dwarf broilers (0.68%) and 'Narmada-XL' (0.37%). Double-yolked eggs were the biggest contributor to defects across all genotypes, concentrated early in the production period, while soft-shelled and membranous eggs became more common later, linked to rising shed temperatures.
03
Early Maturity and High Early Body Weight Predicted Better Egg Output
Genetic correlation analysis showed egg production was positively linked to 20-week body weight but negatively linked to 40-week body weight and age at sexual maturity. In practical terms, this means pullets that matured earlier and were heavier early on, rather than later, tended to lay more eggs overall.