摘要
为研究日粮中添加不同水平杜仲叶对牦牛瘤胃液体外发酵及养分降解率的影响,采用单因素试验设计,分为6个处理组,基础日粮的精粗比为50:50,分别用0%(对照组)、1%、2%、3%、4%、5%的杜仲叶替代基础日粮中的粗料,每个处理组设4个重复。结果表明:(1)与对照组相比,基础日粮中添加杜仲叶培养72 h后,对总产气量(GP)、最大潜在产气量(b)、产气速率(c)、产气前停滞时间(L)和pH没有显著影响(P> 0.05);(2)与对照组相比,各试验组的干物质降解率(DMD)分别提高8.85%、9.15%、11.90%、15.47%、14.55%,粗蛋白质降解率(CPD)分别提高2.20%、4.11%、8.59%、10.72%、7.27%,中性洗涤纤维降解率(NDFD)分别提高5.11%、7.11%、9.50%、13.31%、6.83%,酸性洗涤纤维降解率(ADFD)分别提高11.96%、15.17%、16.57%、16.57%、18.60%、11.25%。随杜仲叶添加水平的提高,日粮中DMD、CPD、NDFD和ADFD呈二次曲线变化(P <0.01),在添加量为4%时达到最大值,添加量提高到5%时,日粮中DMD、CPD、NDFD和ADFD显著降低(P <0.05);(3)与对照组相比,各试验组的NH3-N浓度分别降低4.05%、4.73%、8.68%、11.03%、12.99%,微生物菌体蛋白(MCP)浓度分别提高104.55%、204.55%、222.73%、236.36%、236.36%。瘤胃液中NH3-N浓度随杜仲叶添加水平的提高呈线性下降(P <0.01),而瘤胃液中MCP浓度随杜仲叶添加水平的提高呈二次曲线变化,添加量为1%～3%时MCP浓度显著增加(P <0.01),当添加量为3%以上时,MCP浓度呈现平台模型。综上,日粮中添加杜仲叶可以提高日粮纤维的降解率,降低瘤胃液氨态氮浓度,提高瘤胃微生物蛋白的合成,杜仲叶适宜添加量为3%～4%。
This study aimed to investigate the effects of different levels of Eucommia ulmoides on the rumen liquid fermentation and nutrient degradation rate of yaks by in vitro rumen fermentation.This study used single factor trial design,and was divided into 6 groups with four replicates.The basic diet with the concentrate to forage ratio of 50∶50.The crude material in the basal diet was replaced by 0%(control group),1%,2%,3%,4%,5%Eucommia ulmoides leaves,respectively.The results showed as follows:(1)Compared with the control group,the basal diet supplemented with Eucommia ulmoides leaves had no influence on the total gas production(GP),asymptotic gas production(b),gas production rate(c),stagnant time before gas production(L)and pH in all groups after fermenting for 72 h;(2)Compared with the control group,the dry matter degradation rates(DMD)of treatment groups increased by 8.85%,9.15%,11.90%,15.47%and 14.55%,respectively.The crude protein degradation rates(CPD)increased by 2.20%,4.11%,8.59%,10.72%,and 7.27%,respectively.The neutral detergent fiber degradation(NDFD)increased by 5.11%,7.11%,9.50%,13.31%,and 6.83%,respectively.The acid detergent fiber degradation(ADFD)increased by 11.96%,15.17%,16.57%,16.57%,18.60%,and 11.25%,respectively.The DMD,CPD,NDFD and ADFD in the diet showed a quadratic curve(P<0.01)with the improvement of Eucommia ulmoides leaves.The DMD,CPD,NDFD and ADFD in the diet were significantly increased with the Eucommia ulmoides leaves supplementation level increased up to 4%,then significantly decreased(P<0.05);(3)The concentrations of NH3-N in the treatment groups were decreased by 4.05%,4.73%,8.68%,11.03%and 12.99%,respectively.The concentration of microbial protein(MCP)increased by 104.55%,204.55%,222.73%,236.36%and 236.36%respectively.NH3-N in rumen fluid decreased linearly with the increase of Eucommia ulmoides leaves level(P<0.01),but the concentration of MCP in rumen fluid showed a quadratic curve change with Eucommia ulmoides leaves level increased up to 3%(P<0.05),then reached a platform.In summary,the supplementation of Eucommia ulmoides leaves in the diet could improve the degradation rate of dietary fiber,reduced the ammonia nitrogen concentration in rumen fluid,and increased the synthesis of rumen microbial protein.The suitable supplementation level of Eucommia leaves was 3%~4%.
作者
严欣茹
杨尚霖
郭春华
柏雪
张正帆
万国英
YAN Xinru;YANG Shanglin;GUO Chunhua;BAI Xue;ZHANG Zhengfan;WAN Guoying(Key Laboratory of Animal Science of State Ethnic Affairs Commission,College of Life Science and Technology,Southwest Minzu University,Chengdu,Sichuan Province 610041,China;Guizhou wuxin agriculturalscience andtechnology co.,ltd,Tongren,Guizhou Province 554300,China)
出处
《中国饲料》
北大核心
2019年第9期35-40,共6页
China Feed
基金
西南民族大学研究生"创新型科研项目"硕士生重点项目(CX2018SZ51)
关键词
体外发酵
杜仲叶
牦牛
in vitro fermentation
Eucommia ulmoides
yak
