ABSTRACT The objective of this study was to analyse the impact of dietary vitamin E supplementation on laying performance, serum reproductive hormones concentration and gene expression in ovary and follicles of anti-season breeding goose. A total of 210 anti-season breeding geese were divided into seven treatments with six replications. Each group was supplied with diets containing different vitamin E (DL-α-tocopherol acetate) contents (0, 10, 20, 40, 80, 160, 320mg/kg). We observed that the egg production and laying rate improved significantly at doses of 10 and 80 mg/kg, while the highest egg weight appeared in the 320 mg/kg group. Meantime, 80 mg/kg of vitamin E supplementation significantly improved the concentration of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and estradiol (E2) in serum (p<0.05). Dietary vitamin E supplementation significantly enhanced mRNA expression of FSHR, LHR and ESR1 at a dose of 80mg/kg, while PRLR increased at doses of 10 and 20mg/kg (p<0.05). It was found that the mRNA expression of Dicer increased at doses of 40 and 80 mg/kg of vitamin E supplementation in the ovary, SWF, LWF and SYF, respectively. Thence, Dietary vitamin E supplementation could improve egg laying performance, plasma reproductive hormones and the mRNA expression of reproductive hormone receptor genes in ovary, as well as the mRNA expression of Dicer in ovary, SWF, LWF and SYF. It was supposed that 80 mg/kg of vitamin E supplementation in dietary was appropriate to improve the fertility of anti-season breeding Xingguo grey goose.

ABSTRACT Myostatin (MSTN) is a negative regulator of skeletal muscle growth. In order to investigate whether there is a correlation between MSTN polymorphisms and chicken production performance, in this study, single nucleotide polymorphisms (SNPs) in MSTN gene were examined across 180 Daheng broilers by direct sequencing of PCR product, and the correlations between the genotype and body weight at the age of 1-10 weeks and carcass traits at the age of 73 day were analyzed. Five SNPs (rs313622770, rs313744840, rs316247861, rs314431084, rs317126751) of MSTN gene were identified across Daheng broiler samples, and four haplotypes were reconstructed based on the five SNPs. Results of association analysis showed that four (rs313622770, rs313744840, rs316247861 and rs317126751) of these SNPs had significant association with some growth traits (p<0.05), but there were no significant effect on carcass traits and the four SNPs were strong linkage. For rs314431084, there was no significant correlation between different genotypes and growth or carcass traits. The AA genotype of rs313622770, GG genotype of rs313744840, CC genotype of rs316247861, TT genotype of rs317126751 were good for chicken growth. Diplotypes were significantly associated with chest muscle and leg muscle weight (p<0.05). Overall, these results provide evidence that polymorphisms in MSTN gene are associated with growth traits in chicken. The SNPs in MSTN gene could be utilized as potential markers for marker-assisted selection (MAS) during chicken breeding.