选取20只40日龄、体重8.49 kg±0.51 kg的小尾寒羊公羔,随机分为5组(每组n=4),分别添喂不同剂量的气溶胶OT(0.0、0.4、0.8、1.2、1.6 g/kg日粮),以研究添喂气溶胶OT对羔羊自由采食量和生长性能的影响。同时选取采食量和生长性能最佳的试验组,以无添喂羔羊为对照组,分别在70-80日龄、110-120日龄和170-180日龄,进行3次消化代谢试验,以研究气溶胶OT对羔羊消化代谢的影响,并在240日龄,对以上2组羔羊进行屠宰测定,以研究添喂气溶胶OT对羔羊屠宰性能的影响。结果表明:添喂0.8 g/kg日粮气溶胶OT对羔羊生长和消化代谢的作用效果最好,40-240日龄期间羔羊自由采食量提高15.1%(P〈0.01),日增重增加15.6%(P〈0.01);3期消化代谢试验日粮干物质、有机物、粗蛋白、纤维素和总能的平均表观消化率分别提高19.2%(P〈0.01)、17.5%(P〈0.01)、32.8%(P〈0.01)、19.7%(P〈0.01)和17.9%(P〈0.01),氮、钙和磷平均保留量分别增加29.8%(P〈0.01)、17.5%(P〈0.01)和18.2%(P〈0.01);240日龄羔羊活体重、胴体重、屠宰率、胴体净肉重、胴体瘦肉重和眼肌面积分别增加12.9%(P〈0.01)、22.6%(P〈0.01)、8.6%(P〈0.05)、24.2%(P〈0.01)、32.3%(P〈0.01)和14.0%(P〈0.01),而饲料转化效率(体增重/耗料)不受影响。由试验得出结论:给羔羊添喂适量的气溶胶OT,可以提高羔羊的自由采食量,提高粗蛋白和纤维素的消化率,增加氮保留,改善羔羊的屠宰性能,因而具有较高的潜在应用价值。
20 male Small-tailed Han sheep lambs of 40 day's old,with the body weight of 8.49 kg±0.51 kg,were randomly divided into 5 groups(n=4 in each group),and were supplemented with different doses of aerosol OT(AOT)(0.0,0.4,0.8,1.2 and1.6 g/kg of diet,as DM basis)respectively. The effects of supplemental of aerosol OT on the voluntary intake and growth performance of lambs were studied. Meanwhile,the group with optimum intake and growth performance was selected as experimental group,with the control group(AOT free),to carried on the digestion and metabolism experiment at 70-80,110-120 and 170-180 day's old respectively. And at the age of 240 days,the slaughter performance of the lambs of the two groups was tested.The results showed that the supplement of AOT with 0.8 g/kg of diet had the best effect on growth,digestion and metabolism of lamb,at which the voluntary intake and the daily gain increased by 15.1%(P〈0.01)and 15.6%(P〈0.01)respectively;the apparent digestibility of dietary DM,OM,CP,cellulose and total energy averagely increased by 19.2%(P〈0.01),17.5%(P〈0.01),32.8%(P〈0.01),19.7%(P〈0.01)and 17.9%(P〈0.01)in three period of experiments respectively;the retained amounts of nitrogen,calcium and phosphorus increased by 29.8% (P〈0.01),17.5%(P〈0.01)and 18.2%(P〈0.01)respectively;the live weight,carcass weight,slaughter rate,carcass net meat weight,carcass lean meat weight and loin eye area at the age of 240 days increased by 12.9%(P〈0.01),22.6%(P〈0.01),8.6%(P〈0.05),24.2%(P〈0.01),32.3%(P〈0.01)and 14.0%(P〈0.01)respectively. However,the feed efficiency(body gain/feed consumption)were not affected. It is concluded that a given supplement of OT to lamb may increase the voluntary intake,the digestibility of the crude protein and cellulose,the nitrogen retention,and improve the slaughter performance of lamb,therefore it has a higher value for its potential application.