Internal Traits of Eggs and Their Relationship to Shank Feathering in Chicken Using Principal Component Analysis

Chicken eggs represent an important source of protein to the growing human population and also supply repositories of unique genes that could be used worldwide. The inheritance of shank feathering trait is dominant upon non-feathering shank trait in chicken which is based on two factors: pti-1L and pti-1B that are located on Chromosomes 13, 15, and 24. Using 185 fertile eggs collected from two genetic lines (shank feathering and non-feathering shank) of White Kurdish chicken, we found that egg weight highly (P < 0.01) correlated with yolk weight (r2=0.520, 0.704, respectively), albumen weight (r2=0.918, 0.835), and shell weight (r2=0.626, 0.225). The first two principal components explained the greatest variance in both the White with shank feathering (85.6% of total variance) and non-feathering shank (76.5%). Therefore, differences in the component traits of the eggs between the two genetic lines may be influenced by the same gene actions as shank feathering trait. According to these results, the two genetic lines of Kurdish chicken yield significant differences in the internal traits of eggs.