本试验旨在研究饲粮锌水平对育成期蓝狐生长性能、营养物质消化率及氮代谢的影响。选取8周龄平均体重为(2.21±0.49) kg的健康蓝狐90只,分成5组,通过方差分析调整各组间体重差异不显著(P>0.05),每组18只,公母各占1/2。各组饲粮锌水平分别为39.75(Ⅰ组)、60.00(Ⅱ组)、80.00(Ⅲ组)、100.00(Ⅳ组)、120.00 mg/kg (Ⅴ组)。预试期7 d,正试期60 d。结果表明:1)公狐平均日增重各组间差异不显著(P>0.05);母狐Ⅱ组平均日增重极显著高于Ⅴ组(P<0.01)。2)公狐干物质消化率Ⅱ组极显著高于Ⅰ组和Ⅳ组(P<0.01),显著高于Ⅲ组和Ⅴ组(P<0.05);脂肪消化率Ⅱ组极显著高于Ⅰ组、Ⅲ组和Ⅳ组(P<0.01);蛋白质消化率Ⅱ组极显著高于Ⅰ组、Ⅳ组和Ⅴ组(P<0.01)。3)公狐食入氮Ⅰ组和Ⅳ组极显著高于Ⅱ组(P<0.01);粪氮Ⅰ组、Ⅳ组和Ⅴ组极显著高于Ⅱ组(P<0.01)。母狐尿氮Ⅲ组和Ⅴ组显著高于Ⅱ组(P<0.05);氮沉积Ⅰ组和Ⅱ组极显著高于Ⅴ组(P<0.01),显著高于Ⅲ组(P<0.05);净蛋白质利用率Ⅰ组和Ⅱ组极显著高于Ⅴ组(P<0.01),显著高于Ⅲ组(P<0.05);蛋白质生物学价值Ⅱ组极显著高于Ⅴ组(P<0.01),Ⅰ组和Ⅱ组显著高于Ⅲ组和Ⅴ组(P<0.05)。综合试验结果得出,育成期蓝狐饲粮锌水平为60.00 mg/kg时,可获得较好的生长性能,提高蛋白质利用率,有效减少粪氮和尿氮的排出量。

This experiment was conducted to study the effects of dietary zinc level on growth performance, nutrient digestibility and nitrogen metabolism of growing blue foxes. Nighty 8-week-old healthy blue foxes with an average body weight of (2.21±0.49) kg were divided into 5 groups with 18 foxes per group, each group had 9 male foxes and 9 female foxes, and the average body weight of each group showed no significant difference (P>0.05). The blue foxes were fed the diets with dietary zinc levels of 39.75 (group Ⅰ), 60.00 (group Ⅱ), 80.00 (group Ⅲ), 100.00 (group Ⅳ) and 120.00 mg/kg (group Ⅴ), respectively. The pre-test lasted for 7 days and the trial period lasted for 60 days. The results showed as follows: 1) there was no significant difference in the average daily gain of male foxes among all groups (P>0.05); the average daily gain of female foxes in group Ⅱ was significantly higher than that in group Ⅴ (P<0.01). 2) The dry matter digestibility of male foxes in group Ⅱ was significantly higher than that in groups Ⅰ and Ⅳ (P<0.01), and was significantly higher than that in groups Ⅲ and Ⅴ (P<0.05); the fat digestibility in group Ⅱ was significantly higher than that in groups Ⅰ, Ⅲ and Ⅳ (P<0.01); the protein digestibility in group Ⅱ was significantly higher than that in groups Ⅰ, Ⅳ and Ⅴ (P<0.01). 3) The nitrogen intake of male foxes in groups Ⅰand Ⅳ was significantly higher than that in group Ⅱ (P<0.01); the fecal nitrogen in groups Ⅰ, Ⅳ and Ⅴ was significantly higher than that in group Ⅱ (P<0.01). The urine nitrogen of female foxes in groups Ⅲ and Ⅴ was significantly higher than that in group Ⅱ (P<0.05); the nitrogen deposition in groups Ⅰ and Ⅱ was significantly higher than that in group Ⅴ (P<0.01), and significantly higher than that in group Ⅲ (P<0.05); the net protein utilization in groups Ⅰ and Ⅱ was significantly higher than that in group Ⅴ (P<0.01), and significantly higher than that in group Ⅲ (P<0.05); the biological value of protein in group Ⅱ was significantly higher than that in group Ⅴ (P<0.01), and the biological value of protein in groups Ⅰand Ⅱ was significantly higher than that in groups Ⅲ and Ⅴ (P<0.05). In conclusion, dietary zinc level at 60.00 mg/kg can improve the growth performance and net protein utilization, and decline the drain of fecal nitrogen and urine nitrogen.