应用体外产气和体外消化法评定国外大叶型白三叶营养价值

Evaluation of nutritional values of foreign large-leave white clovers by gas production in vitro and digestion techniques in vitro

试验旨在评定7种国外大叶型白三叶品种盛花期的营养价值。利用常规化学成分分析、体外消化技术和体外发酵产气技术测定7种国外大叶型白三叶主要营养成分、体外消化率和瘤胃微生物发酵产气量。结果表明,7种国外大叶型白三叶品种间粗蛋白质含量存在差异,其中克罗迪克白三叶的CP（粗蛋白）含量最高（16.77%）,胡依阿粗蛋白含量仅为12.15%;中性洗涤纤维（NDF）含量在38.01%~44.42%之间,酸性洗涤纤维（ADF）含量变化范围为15.31%~18.62%。国外不同大叶型白三叶干物质体外消化率（DMD）存在差异,考拉DMD最高（84.21%）,而胡依阿DMD最低（78.53%）;中性洗涤纤维体外消化率（NDFD）在54.76%~64.77%之间,酸性洗涤纤维体外消化率（ADFD）变化范围为13.27%~17.69%,其中胡依阿ADFD最低。7种国外大叶型白三叶间产气量参数变化趋势与体外消化率变化趋势相同,各品种24 h内的产气量占总产气量的90%以上,表明瘤胃微生物对7种国外大叶型白三叶的降解速度快,易于被反刍动物消化利用。

Seven foreign variety of white clover（Trifolium repens L.）, which were Susi, Karina, Bulger,Huia, Kopu, Koala, and Croatico, were evaluated in the present study for their chemical composition,in vitro digestibility and gas production in vitro parameters. The content of crude protein（CP） was sig-nificantly different between varieties（P〈0.05）, and the CP content of Croatico was the highest（16.77%）,Huia was the lowest（12.15%）. The content range of neutral detergent fiber（NDF） and acid detergent fi-ber（ADF） was 38.01%~44.42% and 15.31%~18.62%, respectively. The digestibilities in vitro of drymatter（DM）, NDF, and ADF were significantly different among all varieties（P〈0.05）. The highest ofdigestibility in vitro of DM（DMD） was found in Koala（84.21%）, and lowest in Huia（78.53%）. The di-gestibility in vitro of NDF（NDFD） was from 54.76% to 64.77% among varieties, and digestibility in vi-tro of ADF（ADFD） ranged from 13.27% to 17.69%, the ADFD of Huia was the lowest. The variationtendency of gas production parameters was in line with that of digestibility in vitro among the varietiesof white clover. Gas production between 24 h was accounted for more than 90% of total gas productionwhich means that foreign white clovers were easilydegraded by rumen microorganism and utilizedby ruminant.