补充外源性氨基酸对生长育肥羊增重效果的影响

随机选择健康无病的3月龄萨福克羊(♂)与小尾寒羊(♀)的杂交一代羔羊36只,按照单因子随机设计,随机分成3组,每组12只,分别饲喂含不同氨基酸水平的补饲料,研究氨基酸对羔羊生长和增重的影响。结果表明:使用含0.5%赖氨酸和蛋氨酸预混料羔羊组(试验Ⅰ组)平均日增重216.89 g,含0.25%赖氨酸和蛋氨酸预混料羔羊组(试验Ⅱ组)平均日增重199.78 g,均高于不含氨基酸的羔羊组(对照组175.56g)(P<0.05)。2组羔羊只均获利分别比对照组高21.76元和11.64元,经济效益显著。

云上黑山羊生长育肥公羊能量需要量研究

本试验旨在研究云上黑山羊生长育肥公羊能量需要量。选择体况良好、体重相近(约为30 kg)的云上黑山羊生长育肥公羊50只,随机分为5组,每组10只羊。各组分别饲喂代谢能(ME)水平为8.01(1组)、8.70(2组)、9.39(3组)、10.07(4组)、10.75 MJ/kg(5组)的试验饲粮。预试期15 d,正试期30 d。结果表明:1)3组的平均日增重(ADG)显著高于其他各组(P<0.05),3组的干物质采食量(DMI)显著高于1、2、5组(P<0.05),3组的料重比(F/G)显著低于其他各组(P<0.05)。2)3组的粗蛋白质表观消化率显著高于其他各组(P<0.05),1组的磷表观消化率显著低于其他各组(P<0.05),2、3组的粗灰分表观消化率显著高于1组(P<0.05),5组的中性洗涤纤维和酸性洗涤纤维表观消化率显著高于1组(P<0.05)。3)3、4、5组的总能摄入量、甲烷能、消化能和ME显著高于1、2组(P<0.05),5组的总能表观消化率显著高于1组(P<0.05)。4)对云上黑山羊生长育肥公羊的ADG、ME和代谢体重(W^(0.75))进行回归分析,得到ME需要量回归模型:ME=0.275 W^(0.75)+0.0486 ADG(R^(2)=0.8245)。综上结果得出,云上黑山羊生长育肥公羊的维持ME需要量为0.275 MJ/(kg W^(0.75)·d),每增重100 g的ME需要量为8.385 MJ/d。

Growth Performance and Carcass Traites of F1 Crossbreds from Afshari x Zandi and Fashandi x Zandi Sheep under Feedlot Condition

In order to evaluate the effect of crossbreeding on growth performance and carcass traits, Afshari and Fashandi rams crossed with Zandi ewes. 45 Afshari x Zandi and 30 Fashandi x Zandi lambs recorded in a period of 100 days feedlot. Daily weight gain and dry matter intake significantly affected by crossbreeding which were the highest in Afshari x Zandi group （0.180 ± 0.004 and 1.415 ±0.025, respectively）, but it had no effect on feed conversion ratio. The genetic group affected final feedlot weight, empty body weight, warm carcass weight and carcass efficiency which Afshari ± Zandi group had higher amounts （44.70 ± 1.25 kg, 38.85 1.05 kg, 22.63 ± 0.95 kg and 58.63 ±0.77%, respectively）. The breed of ram lambs had no significant effect on the percentage of thigh, loin, shoulder＇, brisket, fat tail, tallow and total removal fat; however the percentage of thigh was different between two crossbred groups. Lean and fat percentage was higher in Fashandi x Zandi crosses.