摘要
[目的]旨在探讨不同粗饲料组合对肉牛生长性能、干物质消化率及血清生化指标的影响,从而为肉牛育肥过程中合理使用粗饲料提供依据。[方法]试验采用完全随机化设计,将28头平均1.5岁、体重相近(319.86±37.46)kg的健康利木赞×安格斯×西门塔尔三杂公牛随机分为4组,每组7头。对照组粗料饲喂全株青贮(100%),试验I组粗料饲喂青贮玉米(40%)和黄贮玉米(60%),试验II组粗料饲喂青贮玉米(40%)和象草(60%),试验Ⅲ组粗料饲喂黄贮玉米(40%)和象草(60%),精料均为5kg/头·天,试验期每周按头测定一次精料和粗料采食量,全部试验牛栓系饲养并自由饮水。试验期70天,预饲期5天,正试期65天,试验前后空腹称重,记录初重和末重并计算日增重、料重比和经济效益等指标;试验结束前四天,用全收粪法测定干物质消化率;最后一天空腹采集血样测定血清指标。[结果]试验I组的平均日增重最高,为1.198kg/d,试验Ⅲ组最低,为1.106kg/d,但各组之间差异不显著(P>0.05);干物质采食量以试验I组最高,显著高于对照组(P<0.05),但与其它两组差异不显著;粗料采食量各组间无差异,但精料采食量以对照组为最低,试验Ⅲ组最高(P<0.01);对照组干物质消化率显著高于其它三个试验组(P<0.05),以试验Ⅲ组为最低。料重比以试验Ⅲ组最高,对照组最低,但各组之间差异不显著(P>0.05);经济效益以试验I组最高,但各组差异不显著(P<0.05)。血液生化指标除血清中尿素氮水平试验I组显著低于对照组外(P<0.05),其它各血液指标均差异不显著(P>0.05)。[结论]全株青贮玉米作为育肥期肉牛的优质粗饲料,本研究表明其与黄贮玉米组合后相比单独饲喂全株青贮或低质的黄贮玉米与象草组合,提高了肉牛采食量、日增重、饲料转化效率及经济效益,发挥了粗饲料间的组合效应并对精料和粗料的组合效应有促进作用,对南方低质粗饲料的合理利用具有指导意义。
[Objective] The aim of this study was to examine the effect of different roughage combina- tions on growth performance, dry matter digestibility （DMD） and blood biochemical parameters of beefcattle, which would provide a basis for the optimum use of roughage for beef cattle fattening. [-Method] The trial was designed with a randomized complete block. Twenty--eight healthy crossbred Simmental bulls with 319.86±37.46 kg initial live weight and approximately 15--month old were randomly allocated in 4 experimental group randomly, and each group has 7 cattle. Four experimental roughage of diets were. （1）the cattle in the control group was fed 100% corn silage （2） the cattle in the group I was fed 40% corn silage and 60% yellow--corn straw （3） the cattle in the group II was fed with 40% corn silage and 60% elephant grass （4） the cattle in the group HI was fed with 40% corn straw silage and 60% elephant grass, respectively. Each cattle were fed with 5kg every day of concentrate. All experimental cattle were tied and felt free to drink. The experiment period were 70 days which including 5 days pre--trail period and 65 days formal trial period. Concentrate and roughage feed intake were measured once per week. Beef cattle were weighed at first day and last day of the trial, then average daily gain （ADG）. Feed to gain ratio （F/G） and economic benefit were calculated. DMD was measured by collecting full excrement method during the last four days of the experiment. Blood samples were taken at the last day of the experiment to measure serum parameters. [-Result] Results showed ADG was the highest （1. 198 kg · d- 1） in group I and the lowest （1. 106 kg · d-1） in group III, while there were no significant differences in ADG among the four groups （P〉0.05） ; DM intake of group I was the highest and was significantly higher than that of control group （P〈0.05）, but there were no difference with other two groupsl There were no differences in forage in take among groups, but concentrate intake was the lowest in control group and highest in groupⅢ （P〈 0.05） Dry matter digestibility of control group was significantly higher than that of other three groups （P〈0.05）, and it was the lowest in groups Ⅲ Feed to gain ratio （F/G） was the lowest in control group and the highest in group Ⅲ, but there were no significant difference exist among four groups （P〉0.05） Economy benefit was the highest in group I, but no difference was detected among groups; There were no significant differences in blood serum parameters among groups （P〈0.05）, while serum urea nitrogen was greatly decreased in group I compared with the control group （P〈0.05）. [-Conclusion] Corn silage, a high quality roughage for fattening cattle, could improve feed intake, ADG, F/G ratio and economy benefit af ter combined with corn straw silage and elephant grass, and it exerted combing effect of different roughage and improved combing effects of forage and concentrate, which would be significant important to properly utilize low quality forage in south China.
出处
《中国牛业科学》
2017年第4期21-26,共6页
China Cattle Science
基金
南宁市科技开发项目重大科技专项(20162007-1)
关键词
肉牛
青贮玉米
生长性能
血清生化指标
beef cattle
silage maize
growth performance
serum biochemical indices
