Association of Prolactin Gene with Egg Production in Khaki Campbell Ducks

Abstract

Prolactin (PRL) is a polypeptide hormone with a variety of physiological functions, and the PRL gene in the duck is involved, in reproduction, ovarian follicle development and egg formation process. The objective of this study was to investigate polymorphism of the PRL gene and the relationship between PRL genotypes with egg production trait in Khaki Campbell ducks (n = 60) by Polymerase Chain Reaction technique (PCR) for 5 sites, Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) and DNA sequencing. The results showed that only intron1 region was polymorphic. A C/A mutation at the position of the 359 bp in intron1 of the PRL gene was found by DNA sequencing, and results in 3 genotypes GG, GT and TT can be detected by XbaI. The frequencies of genotype GG and allele G were the highest (0.56 and 0.74 respectively). The association analysis between the polymorphism in intron1 of the PRL gene and egg production at 300 days of age (E300D) was carried out. In the Khaki Campbell population, association analysis demonstrated that the C359A polymorphism was significantly associated with E300D (P < 0.05), GT genotype was associated with higher egg production than the GG and TT genotype (53.32, 37.50 and 36.67 eggs, respectively).