Influence of Genotype and Hen Age on the Egg Shape Index

摘要

Shape index was a good indicator to characterize species as well as for egg quality. It seems that shape index affected by genetic and environment factors. In this study, the aim was to determine the influence of genotype and age on the shape index. A total of 789 eggs were collected from four genetic lines (Black, Black with brown neck, White Shank feather and White non-Feathering shank) of the Kurdish Chickens when the hens 52 - 65 week-old. Results indicated that significant differences were observed between the four genetic lines in shape index. White non-feathering shank (WNFS) followed by Black with brown neck (BBN) significantly (P ≤ 0.05) had higher shape index compared with Black (B) and White shank feather (WSF). Moreover, shape index did not significantly affected by interaction between different breeds and different period’s age (week) due to the uniform of egg shape and because it falls within the normal range.