本试验旨在研究饲粮中添加桑叶对育肥猪生长性能、脂肪代谢和肉品质的影响。试验选用初始体重 基本一致的健康"杜×大×长"三元杂交肥育猪63头,随机分为3组,每组3个重复,每个重复7头,分别饲喂基础饲粮、含10%桑叶饲粮、含20%桑叶饲粮,试验期65 d。结果表明:1)和基础饲粮相比,饲粮中添加10%桑叶对育肥猪生长速度影响不显著(P>0.05),板油率和背膘厚度显著降低(P<0.05),平均日增重、眼肌面积、料重比和胴体率差异不显著(P<0.05);2)和基础饲粮相比,饲粮中添加10%桑叶可减缓肌肉pH下降速度,显著提高肌肉肌苷酸和脂肪含量(P<0.05);3)和基础饲粮相比,饲粮中添加20%桑叶显著抑制血清脂肪酶、小肠蔗糖酶活性和降低育肥猪血脂含量(P<0.05),显著提高胰腺、板油脂肪酶活性(P<0.05);饲粮添加10%桑叶显著激活育肥猪肝脏己糖激酶、丙酮酸激酶活性(P<0.05),显著降低肝脏丙酮酸含量(P<0.05)。由此得出,饲粮中添加10%桑叶,不影响育肥猪生长速度,可降低猪板油率和背膘厚度,提高肌肉肌苷酸、脂肪含量,作用机理是通过调控育肥猪蔗糖酶、脂肪酶及肝脏糖代谢酶活性达到对脂肪代谢和沉积的调控。

This experiment was conducted to investigate the effects of dietary mulberry leaves on the growth performance, fat metabolism and meat quality of finishing pigs. Sixty-three finishing pigs with the same body weight of (55.85?1.37) kg were randomly divided into three groups with three replicates in every group and seven pigs in every replicate. Pigs in the three groups were fed a basal diet, the basal diet containing 10% mulberry leaves and the basal diet containing 20% mulberry leaves, respectively. The experiment lasted for 65 days. The results showed as follows: 1) compared with the basal diet, the growth rate of finishing pigs treated with the basal diet containing 10% mulberry leaves was not significantly change (P>0.05), the average daily gain, eye muscle area, feed gain ratio and carcass percentage were also not significantly different (P>0.05), but the leaf lard percentage and back fat thickness were significantly decreased (P<0.05); 2) the 10% mulberry leaves could slow down the decrease speed of pH, and significantly increased the contents of inosinic acid and fat in muscle; 3) the 20% mulberry leaves evidently decreased the activities of serum lipase, small intestine sucrase (P<0.05) and the contents of serum lipid, but the activities of lipase in pancreas and leaf lard were increased significantly (P<0.05); the 10% mulberry leaves could activated the hexokinase and pyruvate kinase activities in liver (P<0.05), and the content of pyruvic acid was decreased evidently (P<0.05). In conclusion, the basal diet containing 10% mulberry leaves can not affect the growth rate of finishing pigs, it can decrease the leaf lard percentage and back fat thickness, increase the contents of inosinic acid and fat in muscle, and the mechanism of effects may be that mulberry leaves can regulate the fat metabolism and deposition through regulating the activities of sucrase, lipase and glucose-metabolizing enzymes in liver.