Principal Component Analysis of Egg Parameters in Yoruba Ecotype, Sussex and Their Cross Bred Chickens

Abstract

The egg parameters of Yoruba Ecotype Chicken (YEC), Sussex (SS) and their cross-bred chickens in the humid tropical region of Nigeria were assessed using principal component analysis. The study used 223 eggs, of which 124 YEC and 99 Sussex eggs were collected. Weekly data on the internal and external egg qualities of the hens were gathered using a vernier caliper, measuring tape and digital scale balance. The data acquired by dimension reduction with factor analysis were subjected to principal component analysis and the SPSS statistical package version 21 was also used to correlate the parameters pertaining to egg qualities. The strains' positive correlation with the traits related to egg quality indicated that PC 1 accounted for the largest portion of the overall variation in the characteristics of eggs. In YEC × YEC, 3PCs with high positive loading for egg width, egg number, egg length and shell thickness best described the characteristics of the egg quality. The characteristics of external quality (egg weight, egg width, shell thickness and shell weight) best characterized strain SS × SS. Comparably, strain SS × YEC was characterized by its external traits, whereas strain YEC × SS was characterized by its internal and external traits related to egg quality. It is concluded from this study that crossbreeding of YEC and SS can introduce variation, leading to a mix of internal and external quality characteristics of eggs. This information can be valuable for breeders who can select breeding pairs based on desired egg quality traits.