饲用甜高粱青贮对肉羊养分利用的影响

Effect of forage sweet sorghum silage on nutrient utilization in mutton sheep

为研究饲用甜高粱(Sorghum dochna)和全株玉米(Zea mays)裹包青贮对杜泊羊和小尾寒羊养分利用的影响,本研究选取杜泊羊[(38.0±0.65)kg,♀]、小尾寒羊[(29.8±0.94)kg,♀]各14只,将同一品种试羊按体重相近原则等数分为两组,分别饲喂裹包青贮(玉米青贮或饲用甜高粱青贮);各组自由采食青贮料,所有动物根据体重的1%及0.5%饲喂精料补充料和苜蓿颗粒,日投喂量分两次饲喂。结果显示,1)饲用甜高粱青贮组肉羊的酸性洗涤纤维(ADF)、中性洗涤纤维(NDF)的表观消化率与玉米青贮组差异不显著(P>0.05),除此之外,前者粪氮损失极显著低于后者(P<0.01);2)玉米青贮组肉羊的养分摄入量、干物质(dry matter,DM)、有机物(organic matter,OM)的表观消化率显著高于饲用甜高粱青贮组(P<0.05)。综合分析,在本研究条件下,饲用甜高粱青贮可以安全地饲喂肉羊,在肉羊育肥中饲用甜高粱青贮比例较高时,应适当降低非蛋白氮的比例、补充可利用的蛋白及可溶性碳水化合物,以此提高氮的利用率。

This study investigated the effects of forage sweet sorghum silage and whole corn silage on the nutrient utilization of sheep.According to the principle of similar weight,fourteen Dorper sheep（38.00±0.65 kg,♀）and fourteen small-tailed han sheep（29.83±0.94 kg,♀）formed the two study groups,respectively.They were free to consume wrapped silage（corn silage or forage sweet sorghum silage）,the concentrate supplements and alfalfa granules were fed twice according to 1% and 0.5% of their body weight.The results revealed the following.1）The apparent digestibility of ADF（acid detergent fiber）and NDF（neutral detergent fiber）in the forage sweet sorghum silage group was not significantly different from those in the corn silage group（P〉0.05）.Furthermore,the loss of fecal nitrogen of the forage sweet sorghum silage group was significantly lower than that of the corn silage group（P〈0.01）.2）The nutrient intake,dry matter（DM）,and organic matter（OM）of corn silage group were significantly higher than those of the forage sweet sorghum silage group（P〈0.05）.It was concluded that under the experimental condition,the proportion of non-protein nitrogen was low,while the proportion of available protein and soluble carbohydrates were high in the forage sorghum silage used for the fattening of sheep.Therefore,the forage sweet sorghum can be used as silage for safe and effective feeding.