Intercorrelation of egg productivity and promoter mutation of prolactin gene in Layar hybrid chickens

Abstract Eggs are a major nutritional resource for the global community due to their high levels of protein and essential nutrients. Preferences for egg quality traits, both interior and exterior, vary across different societies. This study aims to evaluate the productivity of a new hybrid chicken, the Layar, which is a cross between layer and Arab chickens, and to explore its relation to promoter of prolactin ( PRL ) gene mutations. The Layar chickens demonstrated promising production capabilities, although their productivity was slightly below that of pure layer breeds. However, Layar chickens have a shorter laying period (144 days) and produce eggs of excellent quality, featuring a yolk color ratio of 11.7 out of 15 and an eggshell color preferred by Asian consumers, particularly in Indonesian society. The identiJication of PRL promoter mutations conJirmed a correlation between indels and egg productivity, although these mutations were found to be irrelevant to egg quality and characteristics.