湖羊与澳湖F1代羔羊短期育肥效果的比较

本研究以湖羊和澳湖F1代羔羊(澳洲白绵羊♂ × 湖羊♀)为研究对象,对其生长性能、屠宰性能、体组成和肌肉品质进行比较分析,综合评估湖羊与澳湖F1代羔羊育肥效果.随机选择湖羊和澳湖杂交F1代羔羊各61只,在相同的饲养环境和日粮下进行育肥和性能测定.饲养试验结束后立即屠宰,对试验羊只的生长性能、屠宰性能、体组成和肌肉品质等指标进行系统测定和比较.结果显示,湖羊和澳湖F1羔羊育肥期初始体重(0 d)、末期体重(60 d)无显著差异(P>0.05),全期平均日增重(ADG)、平均日采食量(ADFI)无显著差异(P>0.05),但在育肥前期(0～20 d)湖羊的ADG极显著高于澳湖F1代羔羊(P<0.01),而在育肥中期(20～40 d)和后期(40～60 d)澳湖F1代羔羊的ADG均显著高于湖羊(P<0.05).澳湖F1代羔羊的胴体胸围、臀围和眼肌面积显著大于湖羊(P<0.05).澳湖F1代羔羊的心脏重、肝脏重、肺脏重及其相对重(宰前活重)均极显著高于湖羊(P<0.01),但皮毛重、肾周脂重、肠系膜重、尾脂重及其相对重(宰前活重)均极显著低于湖羊羔羊(P<0.01).湖羊的熟肉率和屠宰结束后45 min肌肉pH极显著大于澳湖F1代羔羊(P<0.01),但澳湖F1代羔羊肌肉失水率、屠宰结束后24 h肉色b*2值和l*2值极显著优于湖羊(P<0.05).总体上来看,湖羊早期生长发育较快,但澳湖F1代羔羊后期生长潜力较大,且胴体性能优于湖羊,胴体脂肪沉积比湖羊少,肉用性能明显提高.

Comparative study on short-term fattening of Hu and Australian-Hu F1 lambs

In this study, the production performance, slaughtering performance, body composition, and muscle quality of Hu and Australian-Hu F1 lambs (Australian white sheep ♂ × Hu sheep ♀) were compared and evaluated. Equal numbers (61 each) of Hu and Australian-Hu F1 lambs were randomly selected and kept under the same feeding conditions and diets. Their fattening and performance were measured and they were slaughtered immediately after the fattening period. The results showed that there was no significant difference in the initial body weight (0 d) and final body weight (60 d) (P > 0.05, average daily weight gain and average daily feed intake between Hu and Australian-Hu F1 lambs over the total fattening period, although the daily weight gain of Hu lambs in the early fattening period (0～20 d) was significantly higher than that of Australian-Hu F1 lambs (P > 0.05, while the daily weight gain of Australian-Hu F1 lambs in the middle fattening period (20～40 d) and late fattening period (40～60 d) was significantly higher than that of Hu lambs (P < 0.05). There were no significant differences in carcass weight, dressing percentage, carcass grade (GR), and back fat thickness between Hu and Australian-Hu F1 lambs (P > 0.05), and the differences in carcass chest circumference, carcass hip circumference and eye muscle area in Australian-Hu F1 lambs were significantly higher than in Hu lambs (P < 0.05). Heart weight, liver weight, lung weight and its relative weight (pre-mortem weight) were all significantly (P < 0.01) higher in Australian-Hu F1 lambs than Hu lambs, but fur weight, perirenal fat weight, mesenteric weight, tail fat weight and its relative weight (pre-mortem weight) were all significantly (P < 0.01) lower than Hu lambs. The rate of meat ripening and muscle pH1 45 min were significantly higher in Hu than in Australian-Hu F1 lambs (P < 0.01), but the muscle water loss rate, meat color 24 h b*2 value and meat color 24 h l*2 value were significantly higher in Australian-Hu F1 lambs (P < 0.05). In general, the early growth and development of Hu lambs were faster, but the later growth potential of Australian-Hu F1 lambs was greater, and the carcass performance was better than Hu lambs, with less carcass fat deposition than Hu lambs and significantly improved meat performance.