关键词: 羽色性状, 隐性遗传, 伴性遗传, 豁眼鹅

Abstract:

【Objective】The Huoyan breed of geese is a famous white goose breed in China, 1-day-old gosling of the Huoyan goose are yellow or light yellow. In the offspring of the free mating group, 20% of 1-day-old goslings were found to have a light brown variation during Huoyan goose breeding process, and the ratio of male to female is obviously different (the ratio of male to female is close to 1﹕3), it is speculated that there is a sex-linked inheritance tendency in goose plumage color trait. Using the light brown male geese and yellow female geese as the parents, the hybrid experiment was used to test whether the phenotype of the gosling downy feathers conformed to the Mendelian inheritance law, so as to understand the genetic mechanism of goose plumage color trait. The study on the inheritance and mechanism of feather color traits of goose is of great significance for the breeding of new breeds or strains of goose and the goose specialized line cultivation of auto-sexing by feather color. 【Method】40 males and 200 females of Huoyan geese were chosen to generate the G₁ generation of Huoyan goose pure line by random mating, and plumage color appearance and segregation ratio in G₁ were observed. 4 light brown males and 20 white feather color females of Huoyan geese were chosen to generate the F₁ generation, and plumage color appearance and segregation ratio in F₁ were observed. 【Result】① In the random mating G₁ generation of the Huoyan goose, the proportion of light brown downy feather trait individuals was 19.5%. Among them, the ratio of light brown individuals between male and female chicks is relatively large, the proportion of light brown in male chicks is about 10%, and 30% of females are light brown. According to Hardy-Weinberg’s law, the allele frequency of the color traits of the downy feather is calculated as follows: The ratio of light brown individuals in the female goslings is the frequency of the light brown trait alleles in the Huoyan goose population, in this experiment, 29.8% of the female are light brown, so the frequency of the light brown trait allele is about 0.3. At the same time, the ratio of the light brown individual in the male goslings can also calculate the frequency of the light brown allele, in this case, 10% of the male are light brown, so the frequency of the light brown trait allele is about 0.3. Correspondingly, the frequency of the yellow downy feather trait allele is about 0.7. ②Among the F₁ populations, 81 were yellow feathers, accounting for 50%; 79 were light brown, accounting for 50%. And the yellow feathers are all male, and the light brown feathers are all female. The results showed that the light brown traits were associated with sex-linked inheritance. It has been confirmed that silver feather (S*S) and imperfect albinism (S*AL) are controlled by a pair of alleles located on the Z chromosome, and the imperfect albinism gene AL is recessive to the silver feather gene S. Therefore, based on the results of the hybridization test, it can be concluded that the light brown and yellow are the results determined by the multiple allele of one locus, and the light brown color is recessive inheritance for the yellow trait.【Conclusion】In this experiment, the separation of 1-day-old goslings feather phenotypes was analyzed by downy feather color matching hybridization and random mating test. The results showed that the light brown downy feather color trait of Huoyan goose exhibits recessive heredity to the yellow, and demonstrates sex-linked inheritance. The downy feather color of the Huoyan goose is mainly controlled by the Z chromosome silver feather locus. The variation site of the allele controlling the locus is associated with the corresponding appearance.

Key words: plumage color trait, recessive inheritance, sex-linked inheritance, Huoyan goose