本文旨在研究不同饲喂水平对20~35 kg杜寒杂交公羔的生长性能、屠宰性能和器官指数的影响。采用单因素完全随机区组试验设计,将21只平均体重为(19.14±2.37) kg公羔随机分为3组,按照自由采食(AL组)、自由采食量的70%(IR70组)和自由采食量的40%(IR40组)3个水平饲喂,每组7只羊,每只羊为1个重复。当AL组的试验羊体重达到35 kg时进行屠宰试验,测定生长性能、屠宰性能及重要内脏器官的重量和发育情况。试验期66 d。结果表明:不同的饲喂水平对净增重、平均日增重和干物质采食量有显著的影响(P<0.05),生长性能和部分屠宰指标表现为相同的变化规律,即AL组>IR70组>IR40组,3组之间差异显著(P<0.05);屠宰率、净肉率和胴体净肉率组间无显著性差异(P>0.05);AL组瘤胃重占复胃总重比例最高,为67.08%,与IR70组差异不显著(P>0.05);肝脏重占宰前活重比例以AL组最高,显著高于IR70和IR40组(P<0.05)。结果提示,饲喂水平对肉用绵羊生长性能、复胃的重量与发育、主要生理器官的发育具有不同程度的影响;本试验结果与NRC(2007)肉羊的饲养标准有一定的差距。

This experiment was conducted to investigate the growth performance, slaughter performance and organ indexes of Dorper譙mall Tail Han sheep crossbred male lambs from 20 to 35 kg of live weight. Twenty-one lambs were randomly assigned to three groups with one group fed ad libitum (AL group), and the other two groups fed either 70% (IR70 group) or 40% (IR40 group) of ad libitum. A slaughter trial was performed after the lambs in the AL group reached 35 kg of live weight. The experiment lasted for 66 d. The results showed as follows: different feeding levels had significant effects on net gain, average daily gain and dry matter intake, and partial slaughter indexes among three groups (AL>IR70>IR40) (P<0.05); no significant differences were found in dressing percentage, net meat percentage and net meat percentage of carcass among three groups (P>0.05); in the AL group, the ratio of rumen weight to total complex stomach weight was the highest (67.08%) and no obvious difference was found between AL group and IR70 group (P>0.05). Besides, the ratio of liver weight to live weight in the AL group was higher than that in the other two groups (P<0.05). The results indicate that feeding level has different effects on growth performance, weight and development of complex stomach and other main organs of mutton sheep. Results of growth, slaughter performance and organ indexes of Dorper譙mall Tail Han sheep crossbred male lambs are different from the data reported by NRC (2007).