全株青贮玉米饲喂比例对肉羊增重效果和瘤胃发酵的影响

发布时间：2018-05-15 23:01

  本文选题：全株青贮玉米 + 增重效果　； 参考：《沈阳农业大学》2017年硕士论文

【摘要】：目前全株青贮玉米对肉羊的适宜饲喂比例尚不明确,因此本试验采用单因素试验设计,配制全株青贮玉米比例为30%、40%、50%、60%和70%的五种试验日粮。选择60只平均体重30kg左右三月龄的肉羊,随机平均分成5组,分别饲喂不同全株青贮玉米比例的日粮,进行体外消化培养,通过测定羊的生长情况、营养物质瘤胃降解率和瘤胃内环境,以研究全株青贮玉米饲喂比例对肉羊增重效果和瘤胃发酵的影响,寻求最优全株青贮玉米比例,优化日粮结构。通过对肉羊的育肥,结果表明:随着全株青贮玉米比例的升高,平均干物质采食量下降;40%组增重效果最佳,经济效益最高。试验研究表明:NDF在发酵3h、9h、12h时,30%和40%组降解率显著高于其他组(P0.05);6h时,30%组显著高于其他组(P0.05)。ADF在发酵9h前,30%组、40%组、50%和60%组显著高于70%组(P0.05);在发酵12h时,40%组、50%组和60%组显著高于30%组和70%组(P0.05)。CP在发酵6h前,30%组显著高于其他组(P0.05)。9h时,30%组、40%组和50%组显著高于其他组(P0.05);12h时,30%组、40%组显著高于其他组(P0.05)。DM在发酵3～12h时,30%组、40%组、50%组和60%组显著高于70%组(P0.05)。应用ANKOM RFS系统对五种日粮发酵过程中的产气量并利用发酵12h的瘤胃液对瘤胃内环境进行检测,结果表明:40%全株青贮玉米组产气量最小。瘤胃pH、NH3-N浓度随着全株青贮玉米比例的提高,逐渐减小。乙酸浓度和乙丙比随着全株青贮玉米比例上升而逐渐增大,丙酸浓度随着全株青贮玉米比例上升而逐渐减小,丁酸浓度40%组显著高于其他组(P0.05)。总VFA40%组、50%组和60%组差异不显著(P0.05),但显著高于30%组和70%组(P0.05)。其中40%组总VFA浓度最高。50%组原虫数量显著高于其他组(P0.05),其次40%组最多。在本试验条件下,40%全株青贮玉米饲喂比例对肉羊的生产效率有促进作用。
[Abstract]:At present, the suitable feeding ratio of silage corn to meat sheep is not clear, so the single factor experiment design is adopted in this experiment, and the proportion of the whole silage corn is 30 ~ 40% and 50% and 70% respectively. Sixty meat sheep with average body weight of about three months of 30kg were randomly divided into 5 groups and fed diets with different proportion of silage corn in vitro. The growth of the sheep was measured. The effects of rumen degradation rate and rumen internal environment on the weight gain and rumen fermentation of meat sheep were studied in order to optimize the ration of whole plant silage corn and the structure of diet. Through fattening the meat sheep, the results showed that with the increase of the proportion of silage corn, the average dry matter intake decreased by 40%, the effect of weight gain was the best, and the economic benefit was the highest. The experimental results showed that the degradation rates of the 30% and 40% groups were significantly higher than those of the other groups at 6 h after fermentation for 3 h or 9 h, and 50% and 60% for 40% and 60% groups respectively, and 50% and 60% for 40% and 60% groups for 12 h, respectively, and 50% and 60% for 30% and 60% groups, respectively, at 12 h after fermentation. It was significantly higher in 30% group than in 30% group and 70% group in 30% group before fermentation for 6 h. It was significantly higher in 30% group than that in other group P0.05% group and 50% group at 9 h before fermentation. It was significantly higher in 40% group than in other group P0.05% group at 12 h after fermentation and 40% group in 30% group and in 60% group at 312h after fermenting, which was significantly higher than that of P0.05% group in other groups. The ANKOM RFS system was used to detect the gas production of five diets during fermentation and the rumen fluid for 12 h fermentation. The results showed that the minimum gas production was obtained in the whole plant silage corn group of 40%. The pH value of NH _ 3-N in rumen decreased with the increase of the proportion of silage corn. The concentration of acetic acid and ethylene-propyl acid increased with the increase of the proportion of silage corn, and the concentration of propionic acid decreased with the proportion of silage corn. The concentration of butyric acid in 40% group was significantly higher than that in other groups. There was no significant difference between 50% group and 60% group in total VFA 40%, but it was significantly higher than that in 30% and 70% groups. The number of protozoa in the 40% group with the highest total VFA concentration of .50% was significantly higher than that of the other groups (P 0.05), followed by the 40% group. Under the experimental condition, 40% silage maize feed ratio can promote the production efficiency of meat sheep.
【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S826.5
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本文编号：1894315