饲粮物理结构对杜寒公羊育肥及屠宰性能的影响

Effects of Feed Physical Structure on Fattening and Slaughter Performance of Dorper and Thin-Tailed Han Crossbred Rams

本试验旨在研究饲粮物理结构对杜寒公羊育肥及屠宰性能的影响。选择体重(27.00±3.75)kg的2月龄健康杜寒公羊24只为试验动物,随机分为2组(每组3个重复,每个重复4只羊)。将2组羊分为全混合粉料型饲粮组(对照组)和全混合颗粒型饲粮组(试验组)。2组饲粮配方相同,育肥110 d,其中预试期10 d,正试期100 d。结果表明:试验组平均日增重和饲料转化率显著高于对照组(P<0.05),而平均日采食量显著低于对照组(P<0.05)。试验组净肉率、肌肉的亮度(L^(*))和红度(a^(*))值显著高于对照组(P<0.05),羊肉中粗蛋白质、碳水化合物、钙、镁含量显著高于对照组(P<0.05),骨肉比、内脏器重比显著低于对照组(P<0.05),pH 45 min、滴水损失率、失水率显著低于对照组(P<0.05)。屠宰率、GR值、眼肌面积提高趋势,但差异不显著(P>0.05)。试验结果表明,粉料型饲粮制作成颗粒型饲粮可以显著提高杜寒公羊育肥性能、净肉率、饲料转化率、羊肉新鲜度,也可以显著提高羊肉中粗蛋白质、碳水化合物、钙、镁含量,延长羊肉保鲜时间,提高羊肉品质。综上所述,饲粮物理结构显著影响杜寒公羊的育肥性能、屠宰性能及肉品质。

This experiment was conducted to study the effects of feed physical structure on fattening and slaughter performance of Dorper and thin-tailed Han crossbred rams.Twenty-four 2-month-old crossbred rams with the initial body weight of(27.00±3.75)kg were randomly divided into two groups(3 replicates per group,4 sheep per replicate).Rams in control group were fed powdered total mixed ration,while rams in experimental group were fed pellet total mixed ration.The two groups had the same formula diet.The experiment lasted for 110 days with 10 days for adaptation and 100 days for sampling.The results showed that compared with control group,rams supplemented with pellet total mixed ration had a greater average daily gain(ADG)and feed conversion ratio(P<0.05),while average daily feed intake(ADFI)significantly decreased(P<0.05).The net meat rate,muscle brightness value(L^(*)),redness value(a^(*)),contents of crude protein,carbohydrate,calcium and magnesium were higher for rams fed pellet total mixed ration than those fed powdered total mixed ration(P<0.05).Compared with control group,pellet total mixed ration could tend to increase slaughter rate,GR value and loin eye muscle area(P>0.05).The visceral weight and bone-muscle ratio were significantly lower compared with control group(P<0.05).Meat quality results showed that the pH 45 min,drip loss rate and water loss rate were significantly lower than those of control group(P<0.05).The results show that when the powdered total mixed ration is converted into pellet total mixed ration,the fattening performance,meat net percentage,feed conversion rate and mutton freshness are significantly improved,and the contents of crude protein,carbohydrate,calcium and magnesium in mutton are also significantly increased,and the fresh-keeping time of mutton is prolonged,and the quality of mutton is improved.In conclusion,dietary physical structure significantly affects fattening performance,slaughter performance and meat quality of Dorper and thin-tailed Han crossbred rams.