Phenotypic correlations between egg quality traits, albumen pH and ovalbumin levels in four varieties of Japanese quail (Coturnix coturnix japonica)

This study aimed to reveal phenotypic correlations of some internal and external egg quality traits between egg white (albumen) pH and ovalbumin levels in four different varieties of Japanese quail. A total of 480 eggs were used belong to gray, white, golden and black plumage color Japanese quail obtained from a commercial quail breeding company. Each group consisted of 120 eggs collected from the birds which were same age. After determined the external traits, all eggs were broken, albumen and yolk separated and internal traits were examined. Albumen pH was measured after the separation process. SDS-PAGE was applied for determining the ovalbumin level. A positive correlation was observed between egg weight and albumen (0.838) and yolk weight (0.599). There was a negative correlation determined between egg weight and albumen pH (-0.431). The percentage of yolk and albumen pH had a moderately significant positive correlation (0.350). We observed significant correlation between yolk color and albumen pH as well as between genotype of birds (P<0.01). The ovalbumin level high positively correlated with only the birds’ genotype (0.814). Black plumage color (67.69%) had the highest ovalbumin level amongst golden (64.76%), white (49.28%) and gray (46.84%) plumage colors, respectively. The novel data is presented in this study about ovalbumin level comparing in four varieties of Japanese quail. The ovalbumin level is not affected by any quality features except for the genotype. The studies need to be conducted under different storage conditions for revealing more accurate phenotypic correlations between egg quality traits and albumen pH.