本试验旨在研究棉籽低聚糖对水貂生长性能、营养物质消化代谢、肠道菌群和免疫的影响。试验选择50只健康的雄性水貂,随机分为5组,每组10个重复,每个重复1只水貂。对照组饲喂基础饲粮,试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组分别饲喂在基础饲粮中添加0.5、1.0、2.0、4.0 g/kg棉籽低聚糖的试验饲粮。试验期为45 d。结果表明:饲粮添加棉籽低聚糖对水貂的平均日采食量、平均日增重、料重比均无显著影响(P>0.05),但对平均日采食量和平均日增重有提高的趋势。饲粮添加棉籽低聚糖对水貂各营养物质消化代谢指标以及器官(肝脏、脾脏和肾脏)指数无显著影响(P>0.05)。各试验组肠道中大肠杆菌数量均低于对照组,但差异不显著(P>0.05)。饲粮添加棉籽低聚糖对肠道中乳酸杆菌数量无显著影响(P>0.05)。饲粮添加0.5 g/kg棉籽低聚糖可显著提高水貂肠道中双歧杆菌数量(P<0.05)。各组水貂血清中总蛋白、白蛋白、球蛋白、补体3、补体4、免疫球蛋白M、总甲状腺素和总三碘甲状腺原氨酸的含量均差异不显著(P>0.05)。与对照组相比,饲粮添加0.5 g/kg棉籽低聚糖组血清中免疫球蛋白A含量极显著升高(P<0.01),饲粮添加2.0 g/kg棉籽低聚糖组血清中免疫球蛋白G含量显著降低(P<0.05)。综合各项试验指标,水貂饲粮中棉籽低聚糖适宜的添加量为0.5 g/kg。

This experiment was conducted to investigate the effects of raffinose on growth performance, nutrient digestion and metabolism, intestinal microflora and immune function of minks. Fifty healthy male minks were randomly divided into 5 groups, and each group had 10 replicates and each replicate had 1 mink. The minks in control group was fed a basal diet, and the minks in test groups Ⅰ, Ⅱ, Ⅲ and Ⅳ were fed the experimental diets supplemented with 0.5, 1.0, 2.0 and 4.0g/kg raffinose, respectively. The experiment lasted for 45 days. The results showed as follows: raffinose supplementation had no significant effects on average daily feed intake (ADFI), average daily gain (ADG) and feed/gain (P>0.05), but there had a trend to improve ADFI and ADG. Raffinose supplementation had no significant effects on indices of nutrient digestion and metabolism, and organ (liver, spleen and kidney) indices (P>0.05). The number of intestinal Escherichia coli in the test groups was lower than that in the control group, but the difference was not significant (P>0.05). The number of intestinal Lactobacillus was not significantly affected by raffinose supplementation (P>0.05). The supplementation of 0.5 g/kg raffinose improved the number of intestinal Bifidobacterium bifidum (P<0.05). No significant differences were found in the contents of total protein, albumin, globulin, complement 3, complement 4, immunoglobulin M, total thyroxine (TT₄) and total triiodothyronine (TT₃) in serum among all groups (P>0.05). Compared with the control group, serum immunoglobulin A content in the group supplemented with 0.5 g/kg raffinose was significantly increased (P<0.05), while serum immunoglobulin A content in the group supplemented with 2.0 g/kg raffinose was significantly decreased (P<0.05). Considering above all indices, the optimal level of raffinose in diets for minks is 0.5 g/kg.