关键词: 泰和乌骨鸡, 硒, 黑色素, 生产性能

Abstract: 【Objective】The objective of this study was to investigate the effects of dietary selenium (Se) supplementation on the growth performance and melanin content in tissues of Taihe Silky Fowls and to preliminarily explore the mechanism underlying the effects of selenium on melanin biosynthesis.【Method】A total of 450 one-day old Taihe Silky Fowls were randomly allotted into 6 groups with 5 replicates of 15 birds each. Each group was fed the basal diet supplemented with 0.00, 0.10, 0.30, 0.50, 0.70 or 0.90 mg·kg-1 Se to 4 weeks of age, respectively. At the end of 4 weeks of age, average daily gain (ADG) and feed to gain ratio (F/G) were calculated, and glutathione peroxidase (GSH-Px) activity, tyrosinase (TYR) activity, melanin content in tissues were determined.【Result】Se supplementation in the basal diet significantly improved the growth performance of Taihe Silky Fowls (P＜0.05), and the maximum performance was obtained when Se supplementation level was 0.30 mg·kg-1. GSH-Px and TYR activities in serum, liver, kidney, pectoral muscle and skin were significantly improved and the melanin contents in these tissues were also increased (P＜0.05) when the diets were supplemented with 0.10-0.70 mg·kg-1 Se. Remarkable quadratic curve relationship between Se supplemental levels and ADG, F/G, GSH-Px, TYR activities and melanin content in tissues was observed (P＜0.05). Melanin content in tissues was positively correlated with GSH-Px and TYR activity (P＜0.05), respectively. The optimal Se supplementation level for obtaining maximum melanin content in tissues was higher than for obtaining maximum ADG.【Conclusion】Dietary supplementation with Se could improve growth performance and stimulate melanin biosynthesis of Taihe Silky Fowls, and the optimum Se requirement for melanin deposition in tissues was higher than for maximal growth. The stimulating effect of selenium on melanin synthesis may be related to the increased antioxidant capacity of body exerted by Se.

Key words: Taihe silky fowls, selenium, melanin, growth performance