Journal of Animal Science and Veterinary Medicine

Egg quality is crucial in poultry production, as it significantly impacts market value, hatchability, and profitability. Internal quality traits, such as albumen weight, yolk height, and Haugh unit, are commonly evaluated alongside egg weight. This study aimed to assess the relationship between egg weight and internal egg quality parameters in Harco Black and Isa Brown layer strains to inform strain-specific breeding and nutritional strategies. A total of 100 birds per strain were evaluated at weeks 6 and 7 of lay to minimise age-related variation. Internal egg traits measured included albumen weight and height, yolk weight, length, and height. One-way ANOVA was used to compare traits between strains, and Pearson correlation assessed relationships among variables. Significant strain differences (p < 0.05) were observed in egg weight and several internal traits. At week 6, Harco Black produced heavier eggs with higher albumen and yolk weights than Isa Brown. At week 7, Harco Black maintained superior yolk height and length. In Isa Brown at week 6, egg weight strongly correlated with albumen weight (r = 0.90) and yolk weight (r = 0.74). In Harco Black, albumen height correlated positively with albumen weight (r = 0.63). At week 7, strong correlations existed between egg weight and albumen weight (r = 0.96) in both strains. Additional significant associations were found between albumen height and weight, yolk height, and yolk length. Egg weight influences internal quality; strain-specific differences should therefore guide breeding programmes for quality improvement.