本试验旨在研究维生素C对育成期水貂生长性能、养分消化率及氮代谢的影响。试验选用60日龄育成期水貂120只，随机分为6组，每组20只（10只公貂、10只母貂）。Ⅰ组（对照组）饲喂基础饲粮，Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ组分别在基础饲粮中添加25、50、100、200和400 mg/kg维生素C。预试期7 d，正试期58 d。结果表明：1）Ⅳ组公貂的平均日采食量极显著高于Ⅰ和Ⅲ组（P<0.01），显著高于Ⅱ、Ⅴ和Ⅵ组（P<0.05）；Ⅲ组公貂的料重比显著低于Ⅰ、Ⅱ和Ⅵ组（P<0.05）。Ⅳ组母貂的平均日采食量极显著高于Ⅰ和Ⅱ组（P<0.01），Ⅰ、Ⅱ、Ⅲ、Ⅳ组母貂的料重比显著低于Ⅵ组（P<0.05）。2）Ⅲ组公貂的粗蛋白质消化率显著高于Ⅱ、Ⅴ组（P<0.05），Ⅲ、Ⅳ、Ⅴ、Ⅵ组公貂的钙消化率极显著高于Ⅰ、Ⅱ组（P<0.01）。Ⅳ组母貂的粗蛋白质消化率显著高于Ⅰ、Ⅱ组（P<0.05）。3）Ⅳ、Ⅴ、Ⅵ组公貂的尿氮显著低于Ⅰ组（P<0.05），Ⅳ组公貂的沉积氮显著高于其余各组（P<0.05），Ⅲ、Ⅳ、Ⅵ组公貂的蛋白质生物学价值显著高于Ⅱ组（P<0.05）。综上所述，在水貂饲粮中添加适量的维生素C能够提高水貂的生长性能、养分消化率和氮代谢水平。育成期水貂饲粮中维生素C适宜添加水平为50~100 mg/kg。

This experiment was conducted to study the effects of vitamin c on growth performance, nutrient digestibilities and nitrogen metabolism of growing minks. One hundred and twenty 60-day-old growing minks were randomly divided into 6 groups with 20 minks in each group (10 male minks and 10 female minks). Minks in group Ⅰ (control group) were fed a basic diet, and others in groups Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ were fed basic diets supplemented with 25, 50, 100, 200 and 400 mg/kg vitamin C, respectively. The pre-experimental period lasted for 7 days, and the experimental period lasted for 58 days. The results showed as follows:1) the average daily feed intake of male minks in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅲ (P<0.01), and significantly higher than that in groups Ⅱ, Ⅴ and Ⅵ (P<0.05); the feed to gain ratio of male minks in group Ⅲ was significantly lower than that in groups Ⅰ, Ⅱ and Ⅵ (P<0.05). The average daily feed intake of female minks in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅱ (P<0.01), and the feed to gain ratio of female minks in groups Ⅰ, Ⅱ, Ⅲ and Ⅳ was significantly lower than that in group Ⅳ (P<0.05). 2) The crude protein digestibility of male minks in group Ⅲ was significantly higher than that in groups Ⅱ and Ⅴ (P<0.05), and the calcium digestibility of male minks in groups Ⅲ, Ⅳ, Ⅴ and Ⅵ was significantly higher than that in groups Ⅰ and Ⅱ (P<0.01). The crude protein digestibility of female minks in group Ⅲ was significantly higher than that in groups Ⅰ and Ⅱ (P<0.05). 3) The urine nitrogen of male minks in groups Ⅳ, Ⅴ and Ⅵ was significantly lower than that in group Ⅰ (P<0.05), the nitrogen deposition of male minks in group Ⅳ was significantly higher than that in the other groups (P<0.05), and the biological value of protein of male minks in groups Ⅲ, Ⅳ and Ⅵ was significantly higher than that of group Ⅱ (P<0.05). In conclusion, dietary appropriate amount of vitamin C can improve the growth performance and nutrient digestibilities of minks, and improve the nitrogen metabolism level. The suitable dietary supplemental level of vitamin C of growing minks is 50 to 100 mg/kg.