不同营养水平全混合日粮对舍饲育肥羔羊生产性能、养分表观消化率和屠宰性能的影响

为了研究3种营养水平(A₁-0.7×NRC、A₂-0.8×NRC、A₃-0.9×NRC)全混合日粮对舍饲羔羊生产性能、养分表观消化率和屠宰性状的影响,本试验选择48只南非肉用美利奴×甘肃高山细毛羊杂交一代羔羊,随机分为3个处理组,进行为期60 d的育肥试验。结果显示,在全混合日粮饲喂技术下,饲喂A₂、A₃营养水平日粮组的羔羊全期平均日增重极显著高于A₁营养水平组(P<0.01),A₂和A₃营养水平组差异不显著(P>0.05),公羔全期平均日增重极显著高于母羔(P<0.01);A因子对钙、总磷、中性洗涤纤维、酸性洗涤纤维消化率均有极显著影响(P<0.01),性别仅对钙、总磷消化率有极显著影响(P<0.01),但营养水平与性别没有显著交互作用(P>0.05);营养水平对育肥羔羊的屠宰性能没有显著影响(P>0.05),但杂种羔羊的屠宰率、熟肉率、眼肌面积等高于甘肃高山细毛羊。以上结果表明采用0.8×NRC营养水平全混合日粮育肥南非肉用美利奴×甘肃高山细毛羊杂交一代羔羊较为适宜,在同一营养水平下,公羔生长性能优于母羔。

Effects of different nutrition levels in total mixed rations on production performance, apparent digestibility,and slaughter performance in yard feeding lambs

The effects of three nutrition levels(A1,0.7×NRC,A2,0.8×NRC,A3,0.9×NRC) in total mixed rations on production performance,apparent digestibility and slaughter performance was evaluated.Forty-eight lambs were randomly divided into three groups for a two months feeding trial.The average daily weight gains of the A2 and A3 groups were significantly(P<0.01) higher than that of the A1 group.There was no significant difference between A2 and A3.The average daily gain of ram lambs was significantly(P<0.01) higher than that of ewe lambs.Different nutrition levels had significant effects on apparent digestibility of Ca,total phosphorus(TP),neutral detergent fibre(NDF) and acid detergent fiber(ADF)(P<0.01).Sex factors had significant effects on apparent digestibility of Ca and TP(P<0.01).There were no difference in slaughter indexes(P>0.05) but the slaughter rate,cooking rate and loin eye area of hybrid lambs were significantly higher than those of Gansu alpine fine wool sheep.In summary,the 0.8×NRC nutritional level was better for fattening hybridized lambs of crossed SA Mutton Merinos,and ram lambs grew better than ewe lambs at the same nutritional levels.