摘要
本试验将体外瘤胃发酵试验与动态产气实时记录技术相结合,分析了高精料全混合日粮中产朊假丝酵母(Candida utilis,CU)添加水平对体外瘤胃发酵特性和纤维降解的影响。试验用瘤胃液采自5头泌乳期荷斯坦奶牛。试验分为6组,各组CU添加水平分别为0(对照组)、0.53×106、1.07×106、1.60×106、2.13×106、2.67×106CFU/mL。测定72 h累计产气量、产气动力学参数和瘤胃发酵特性指标。结果表明,随CU添加水平的升高,底物的营养物质(干物质、中性洗涤纤维、酸性洗涤纤维)体外消失率、各时间点产气量、72 h累积产气量、产气动力学参数(理论最大产气量和达到1/2理论最大产气量的时间)、微生物蛋白质与总挥发性脂肪酸浓度以及丙酸、戊酸与支链脂肪酸含量均显著或极显著升高(P<0.050或P<0.001),而乙酸、丁酸含量以及甲烷生成量则极显著降低(P<0.001)。因此,添加CU可提高瘤胃微生物纤维降解与发酵效率。此全混合日粮条件下,CU最适添加水平为2.67×106CFU/mL。
In vitro ruminal fermentation test and real-time gas production recording technique were combined to determine effects of Candida utilis （CU） supplemental level in high concentrate total mixed ration on in vitro ruminal fermentation characteristics and fiber degradation. Ruminal fluid was collected from five lactating Hol- stein cows. The CU was supplemented at levels of 0 （ control group）, 0.53 × 10^6, 1.07 ×10^6, 1. 60 × 10^6, 2. 13× 10^6 and 2.67 × 10^6 CFU/mL, respectively. The indices of 72 h accumulative gas production, kinetic parameters of gas production and ruminal fermentation characteristics were determined. The results showed as follows ： with the increase of CU supplemental level, in vitro disappearance rates of nutrients （ dry matter, neu- tral detergent fiber and acid detergent fiber） in the substrate, gas production at different time points, 72 h accu- mulative gas production, kinetic parameters of gas production （ theoretical maximum gas production and time of reaching 1/2 of it） and microbial protein and total volatile fatty acids concentrations as well as propionic acid, valeric acid and branch-chain fatty acids contents were significantly increased （P 〈 0. 050 or P 〈 0. 001 ）, whereas acetic acid and butyric acid contents and methane production were significantly decreased （ P 〈0. 001 ）. In summary, the supplementation of CU can increase degradation and fermentation of fiber by ruminal microbes. Under conditions of the present total mixed ration, the optimal supplemental level of CU is 2.67 × 10^6 CFU/mL. l- Chinese Journal of Animal Nutrition, 2014, 26（4） ：940-9461
出处
《动物营养学报》
CAS
CSCD
北大核心
2014年第4期940-946,共7页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家重点基础科学研究计划(2011CB100801)
国家科技支撑计划项目(2012BAD12B02)
关键词
产朊假丝酵母
体外瘤胃发酵
产气动力学参数
全混合日粮
Candida utilis
in vitro rumen fermentation
kinetic parameters of gas production
total mixed ra-tion
