本试验旨在研究饲粮烟酸添加水平对产蛋期种鹅产蛋性能、蛋品质和血清生化指标的影响。选择34周龄体况相近的种鹅180只，随机分为6组，每组6个重复，每个重复5只鹅（1公4母）。各组（Ⅰ~Ⅵ组）饲粮烟酸添加水平分别为0、10、20、30、40、50 mg/kg。预试期1周，正试期10周。结果表明：1）饲粮烟酸添加水平对产蛋期种鹅平均日采食量、产蛋率、平均蛋重影响不显著（P>0.05）；但当饲粮烟酸添加水平为40 mg/kg时平均日采食量、产蛋率、平均蛋重均达到最大值。Ⅴ组的料蛋比显著高于Ⅰ和Ⅱ组（P<0.05）。2）饲粮烟酸添加水平对产蛋期种鹅蛋形指数、蛋白高度、蛋黄颜色、蛋黄比率和哈氏单位影响不显著（P>0.05）。Ⅴ组蛋壳强度显著高于Ⅰ、Ⅱ、Ⅲ组（P<0.05），Ⅴ组蛋壳厚度显著高于Ⅰ、Ⅱ组（P<0.05）。3）饲粮烟酸添加水平对产蛋期种鹅血清总蛋白、白蛋白、葡萄糖、尿酸含量及谷草转氨酶活性影响不显著（P>0.05）。Ⅳ、Ⅴ、Ⅵ组血清甘油三酯含量显著低于Ⅰ、Ⅱ组（P<0.05），Ⅲ、Ⅳ、Ⅴ、Ⅵ组血清总胆固醇含量显著低于Ⅰ组（P<0.05），Ⅰ组血清低密度脂蛋白胆固醇含量显著或极显著高于其他各组（P<0.05或P<0.01），Ⅴ、Ⅵ组血清高密度脂蛋白胆固醇含量显著或极显著高于Ⅰ组（P<0.05或P<0.01）。由此可见，饲粮添加烟酸可以降低产蛋期种鹅料蛋比，提高蛋壳厚度和蛋壳强度，降低血清中甘油三酯、总胆固醇、低密度脂蛋白胆固醇含量，提高血清高密度脂蛋白胆固醇含量。建议产蛋期种鹅饲粮烟酸添加水平为40 mg/kg，此时饲粮中烟酸总含量为69.16 mg/kg。

This experiment was conducted to study the effects of dietary niacin supplemental level on laying performance, egg quality and serum biochemical indices of breeding geese during laying period. A total of 180 thirty-four-week-old breeding geese with the similar body condition were randomly divided into 6 groups with 6 replicates per group and 5 geese per replicate (1 male and 4 female). Geese in the 6 groups (groups Ⅰ to Ⅵ) were fed experimental diets supplemented with 0, 10, 20, 30, 40 and 50 mg/kg niacin, respectively. The pre-experimental period lasted for 1 week, and the experimental period lasted for 10 weeks. The results showed as follows:1) dietary niacin supplemental level had no significant effects on the average daily feed intake, laying rate and average egg weight of breeding geese during laying period (P>0.05). When dietary niacin supplemental level was 40 mg/kg, the average daily feed intake, laying rate and average egg weight got the maximal value. The feed to egg ratio of group Ⅴ was significantly higher than that of groups Ⅰ and Ⅱ (P<0.05). 2) Dietary niacin supplemental level had no significant effects on egg shape index, albumen height, yolk color, yolk ratio and Haugh unit of breeding geese during laying period (P>0.05). The eggshell strength of group Ⅴ was significantly higher than that of groups Ⅰ, Ⅱ and Ⅲ (P<0.05), and the eggshell thickness of group Ⅴ was significantly higher than that of groups Ⅰ and Ⅱ (P<0.05). 3) Dietary niacin supplemental level had no significant effects on contents of total protein, albumin, glucose and uric acid and activity of glutamic oxaloacetic transaminase in serum of breeding geese during laying period (P>0.05). The serum triglyceride content of groups Ⅳ, Ⅴ and Ⅵ was significantly lower than that of groups Ⅰ and Ⅱ(P<0.05), the serum total cholesterol content of groups Ⅲ, Ⅳ, Ⅴ and Ⅵ was significantly lower than that of group Ⅰ(P<0.05), the serum low density lipoprotein-cholesterol content of groups Ⅰ was significantly higher than of other groups (P<0.05 or P<0.01) and the serum high density lipoprotein-cholesterol content of groups Ⅴ and Ⅵ was significantly higher than that of group Ⅰ (P<0.05 or P<0.01). In conclusion, dietary niacin can reduce the feed to egg ratio of breeding geese during laying period, improve the eggshell thickness and eggshell strength, decrease the contents of triglyceride, total cholesterol and low density lipoprotein-cholesterol in serum, improve the serum high density lipoprotein-cholesterol content. It is suggested that the dietary niacin supplemental level of breeding geese during laying period is 40 mg/kg, at present, the dietary total niacin content is 69.16 mg/kg.