Effect of Selenium on Hatchability and Cellular Glutathione Peroxidase mRNA Expression during Embryogenesis in Japanese Quail ( Coturnix japonica)

Cellular glutathione peroxidase has important antioxidant and detoxification functions by protecting cells from oxidative damage induced by reactive oxygen species. To investigate the expression of cellular glutathione peroxidase mRNA during embryogenesis in Japanese quail, livers were collected at day 6, 9, 12, 15 and 17 of incubation for measurement of mRNA levels by RT-PCR. The result showed that cellular glutathione peroxidase mRNA expresses in all stages during embryonic development. To observe the effect of selenium in maternal diet on the hatchability and cellular glutathione peroxidase mRNA expression in the liver of hatchlings, mother quail were fed regular diet (0.24 ppm selenium) with 0, 0.25, 0.5 or 1 ppm selenium. After 2 weeks of feeding, fertilized eggs were collected and incubated. Livers of the mothers and the hatchlings were collected for measurement of cellular glutathione peroxidase mRNA expression. The results showed that the hatchability was high in eggs from quail fed 0.25 ppm selenium, but it was decreased in eggs from quail fed 0.5 or 1 ppm selenium. Cellular glutathione peroxidase mRNA levels of female quail fed 0.25, 0.5 or 1 ppm selenium were higher than those fed regular diet. Cellular glutathione peroxidase mRNA levels of the hatchlings originating from the quail fed 0.25 ppm selenium were higher than those of the hatchlings from the quail fed regular diet. These results indicated that although selenium is important for embryonic development through antioxidant defense system by cellular glutathione peroxidase, high level of selenium in the maternal diet has an adverse effect on embryonic development.