为了研究香芹酚对绵羊瘤胃体外养分降解率、发酵特性及体外产气量的影响，在瘤胃液中分别添加0、100、250、500、1 000 mg/L不同浓度的香芹酚，瘤胃发酵48 h后测定养分降解率、发酵参数及总产气量。结果表明，添加250 mg/L试验组的中性洗涤纤维降解率(NDFD)和酸性洗涤纤维降解率(ADFD)显著高于添加500 mg/L、1000 mg/L试验组和对照不添加香芹酚(P ＜ 0.01)。添加250 mg/L试验组的干物质降解率(DMD)显著高于其他试验组(P ＜ 0.01)，而对照的DMD显著低于其他试验组(P ＜ 0.01)。添加1000 mg/L试验组的pH显著高于其他组(P ＜ 0.01)。添加250 mg/L试验组的乙酸浓度显著高于其他试验组(P ＜ 0.01)、丙酸浓度显著高于其他试验组(P ＜ 0.01)。香芹酚含量的增加均显著降低了丁酸的浓度(P ＜ 0.01)。综上所述，在绵羊瘤胃体外培养液中加入香芹酚有助于增加饲草的营养降解量，调整瘤胃发酵作用特点，从而减少总产气量。体外条件下的香芹酚，加入总量不应超过250 mg/L。

The purpose of the experiment was to study the effects of carvacrol on nutrient degradation rate， fermentation characteristics and in vitro gas production in sheep rumen. This time， a single-factor completely randomized trial design was adopted， and rumen fluid was added with 0(control group)， 100， 250， 500 and 1 000 mg/L， respectively. Nutrient degradation rate， fermentation parameters and total gas production were determined after rumen fermentation for 48 h. The results showed that the neutral detergent fiber degradation rate(NDFD) and acid detergent fiber degradation rate(ADFD) in 250 mg/L group were significantly higher than those of experiments in 500 mg/L and 1 000 mg/L group and control group(P ＜ 0.01). Dry matter degradation rate (DMD) in 250 mg/L group was significantly higher than that of the other groups (P ＜ 0.01)， while the DMD of the control group was significantly lower than that of the other groups (P ＜ 0.01). The pH value of 1 000 mg/L group was significantly higher than that of other groups(P ＜ 0.01). The concentration of acetic acid in 250 mg/L group was significantly higher than that of other groups(P ＜ 0.01)， and the concentration of propionic acid was significantly higher than that of other groups(P ＜ 0.01). The concentration of butyric acid was significantly decreased with the increase of carvacrol content(P ＜ 0.01). In conclusion， the addition of carvacrol to the in vitro rumen culture medium of sheep can improve the nutrient degradation rate of the feed， adjust the rumen fermentation characteristics， and reduce the total gas production. Under in vitro conditions， the total amount of carvacrol added should not exceed 250 mg/L.

S816

中央高校本科生科研创新项目(1012021XBMU21107)；西北民族大学人才引进项目(Z20066)；国家民委专项(31929210004)；甘肃省青年科技基金计划(21JR1RA213)。