Abstract: 【Objective】The Huoyan breed of geese which possesses a good laying performance, is a precious native poultry resource of China. As the breed characteristics of Huoyan goose, they need to be studied about the inheritance patterns of Huoyan trait. The purpose of this study was, by establishing the goose-F₂ resource group with Huoyan trait records, combined with the phenotypic analysis, to test the hypothesis that the allele that determines Huoyan trait demonstrates recessive inheritance, so as to understand the genetic mechanism of Huoyan trait. Our findings of the study will lay a theoretical basis for utilization of Huoyan goose genetic resource.【Method】Twenty males and 100 females of Huoyan geese were chosen to generate the F₁ generation of Huoyan goose pure line by random mating, and Huoyan appearance and segregation ratio in F₁ were observed. By F₂-design of outbreed populations, the resource population with Huoyan trait records was established, in which the 3 males and 15 females of Huoyan geese were crossed reciprocally with the 3 males and 15 females of Sichuan White geese, and inter se matings in F₁ were carried out to generate the F₂ population without inbreeding. Huoyan appearance and segregation ratio in F₁ and F₂ were observed.【Result】① Huoyan and normal eyelid phenotype in F₁ generation of Huoyan goose pure line by random mating was 89% (n=444) and 11% (n=444), respectively. The real ratio of Huoyan vs normal eyelid phenotype of males was 7﹕1(n=238), which was no significant with the theoretic value (χ²=2.09＜χ²_0.05(1)=3.84), and the real ratio of Huoyan vs normal eyelid phenotype of females was 10﹕1(n=206), which was no significant with the theoretic value (χ²=0.06＜χ²_0.05(1)=3.84). It indicated that the hypothesis of the allele that determines Huoyan trait demonstrates recessive inheritance is correct, and that Huoyan trait may be determined by two loci, one influences the formation of eyelid, and another modifies the penetrance of the Huoyan phenotype. ②All of the males and females in reciprocal cross F₁ populations of female Huoyan goose crossed with Sichuan White goose ganders were normal eyelid. It indicated that the Huoyan trait exhibits recessive heredity to normal eyelid trait. ③ In F₁ populations of Huoyan goose gander crossed with female Sichuan White goose, 100% (n=71) of the males were normal eyelid, as well as the females with Huoyan and with normal eyelid phenotype were 83% (n=76), 17% (n=76), respectively. The real ratio of Huoyan vs normal eyelid phenotype of females was 5﹕1(n=76), which was of no significance with the theoretic value by the χ² test (χ²=3.51＜χ²_0.05(1)=3.84). It indicated that the Huoyan trait demonstrates sex-linked inheritance. ④ In F₂ populations of Huoyan goose ganders crossed with female Sichuan White goose, the real ratio of Huoyan vs normal eyelid phenotype of males and females were 5﹕8 (n=102), 2﹕3 (n=94), respectively, by the χ² test, and they were of no significance with the theoretic value (χ²=0.36, 0.02＜χ²_0.05(1)=3.84). Meanwhile, in F₂ populations of reciprocal cross, the real ratio of Huoyan vs normal eyelid phenotype of males and females were 0﹕1(n=61), 5﹕7(n=60), respectively, by the χ² test, they were of no significance with the theoretic value (χ²=0.02＜χ²_0.05(1)=3.84). The separation results of Huoyan phenotype in F₂ populations reciprocally further proved that the Huoyan trait demonstrates recessive sex-linked inheritance【Conclusion】The Huoyan trait exhibits recessive heredity to normal eyelid trait, and demonstrates sex-linked inheritance. The Huoyan trait is determined by two loci, one gene is on the Z chromosome, and another modifier gene exists on the autosome.

Key words: Huoyan trait, recessive inheritance, sex-linked inheritance, goose-F₂ resource population, Huoyan goose