不同饲养标准对杜寒杂交肉用绵羊生产和屠宰性能的影响

本试验通过比较不同饲养标准杜寒杂交肉用绵羊增重、器官发育、屠宰性能及肉品质的差异,确定适宜的饲养标准。采用单因素试验设计,选取体重为(28.30±0.86)kg的杜寒杂交F1代肉羊600只,随机分为4组,每组3个重复,每个重复50只。4组分别饲喂按照以下饲养标准配制的饲粮:本实验室(中国农业科学院饲料研究所农业部饲料生物技术重点实验室)提出的杜寒杂交肉用绵羊饲养标准、美国NRC(2007)、英国AFRC(1993)以及我国农业行业标准的《肉羊饲养标准》(NY/T 816—2004),分别记为CARS、NRC、AFRC和HB。试验期81 d,每3 d记录1次采食量,每20 d进行1次称重,当CARS组羊只的平均体重达到44 kg时,每组选取10只羊进行屠宰,测定其屠宰性能、组织器官重量和肉品质等指标。结果表明:不同组羊只的实际干物质采食量,NRC组AFRC组CARS组HB组,其中NRC组与CARS和HB组间差异显著(P0.05),其他组间差异均不显著(P0.05);平均日增重和胴体重,CARS、HB、AFRC组间差异均不显著(P0.05),且均显著高于NRC组(P0.05);饲料转化率各组间存在显著差异(P0.05),CARS组HB组AFRC组NRC组;屠宰率,CARS组显著高于NRC组(P0.05),与HB、AFRC组间差异均不显著(P0.05);CARS组羊只的心脏、肝脏、肾脏重量占宰前活重比例显著高于其他组(P0.05);背最长肌失水率、肌肉色亮度、红度和黄度值,各组间均无显著性差异(P0.05)。结果提示,杜寒杂交肉羊在不同饲养标准下的实际日增重200~220g,从增重和屠宰性能上来看,CARS制订的饲养标准与国外饲养标准相比具有明显优势。

Effects of Different Feeding Standards on Growth and Slaughter Performance of Dorper×Thin-Tailed Han Crossbred Meat Lambs

In order to provide the basis for determination of appropriate feeding standard, this experiment com?pared the effects of different feeding standards on weight gain, organ development, slaughter performance and meat quality of Dorper×thin?tailed Han crossbred meat lambs. Six hundreds Dorper×thin?tailed Han crossbred male lambs (28.30±0.86) kg of body weight] were randomly assigned into 4 groups with 3 replicates in each group and 50 lambs per replicate in a single factor experimental design. The experimental diets were for?mulated according to the following four feeding standards: feeding standard established by our laboratory ( key laboratory of feed biotechnology of the ministry of agriculture, feed research institute, Chinese academy of ag?ricultural sciences) based on the study of nutrient requirements of Dorper×thin?tailed Han crossbred sheep ( ab?breviated to ‘CARS’ ) , NRC ( 2007, USA) , AFRC ( 1993, UK) and Feeding Standard OF Meat?Produ?cing Sheep and Goats of Chinese agricultural industry standards ( HB, NY/T 816—2004 ) . The experiment lasted for 81 d, feed intake was recorded every 3 days and lambs were weighed every 20 days. Ten lambs in each group were slaughtered to determine slaughter performance, tissue and organ weight and meat quality after the lambs in CARS group reached 44 kg of average body weight. The results showed as follows: actual dry matter intake showed NRC group>AFRC group>CARS group>HB group, and significant differences were ob?served between NRC group and CARS or HB groups ( P<0.05) , but there was no significant difference among the other groups ( P>0.05) . For average average daily gain and carcass weight, no significant differences were observed among CARS, HB and AFRC groups (P>0.05), but these groups were significantly higher than NRC group ( P<0.05) . There were significant differences of feed conversion ratio among groups ( P<0.05) , and CARS group0.05) . The percentages of heart, kidneys and liver weight of live weight before slaughter in CARS group were significantly higher than those in the other three groups ( P<0.05) . Water losing rate and meat col?or’ s L?, a? and b?values of the longissimus were not significantly different among all groups ( P>0.05) . In conclusion, the actual average daily gain of Dorper × thin?tailed Han sheep crossbred meat lambs is 200 to 250 g; From weight gain and slaughter performance aspects, the standard of CARS has advantages over for?eign feeding standards.