Kim Do Hyung, Lee Shin Ja, Oh Da Som, Lee Il Dong, Eom Jun Sik, Park Ha Young, Choi Seong Ho, Lee Sung Sill
Department of Animal Science, Gyeongbuk Provincial College, Yecheon 36830, Korea.
Institute of Agriculture and Life Science and University-Centered Labs, Gyeongsang National University, Jinju 52828, Korea.
Asian-Australas J Anim Sci. 2018 Oct;31(10):1635-1642. doi: 10.5713/ajas.18.0045. Epub 2018 Apr 12.
This study was conducted to evaluate the effects of Rhus succedanea extract addition on in vitro ruminal fermentation and microbial growth.
Two ruminally-fistulated steers consuming 600 g/kg timothy- and 400 g/kg cracked corn-based concentrate with free access to water and mineral block were used as rumen fluid donors. In vitro batch fermentation, with timothy as a substrate, was conducted for up to 72 h, with Rhus succedanea extracts added to achieve final concentrations of 0, 10, 30, 50, 70, and 90 mg/L.
Effective dry matter (DM) degradability rate linearly decreased (p = 0.046) depending on extract dosing levels. Total gas production after 24 to 72 h incubation tended to decrease following extract addition, beginning with 50 mg/L starting dose (significance of quadratic effects: p = 0.006, p<0.001, and p = 0.008 for 24, 48, and 72 h, respectively). Methane production decreased depending on dosing levels following 24 h (p<0.05) and 48 h (p<0.005) incubations and was the lowest with the 50 mg/L dose. The Rhus succedanea extracts increased the abundance of Fibrobacter succinogenes (p<0.05) and Ruminococcus flavefaciens (p = 0.0597) and decreased the abundance of methanogenic archaea (p<0.05) following 24 h incubation.
Rhus succedanea was shown to reduce methane production and increase cellulolytic bacteria without any signs of toxic effects and with a minor effect on DM degradability.
本研究旨在评估添加漆树提取物对体外瘤胃发酵和微生物生长的影响。
选用两头装有瘤胃瘘管的肉牛作为瘤胃液供体，它们以含600 g/kg梯牧草和400 g/kg碎玉米的精饲料为食，可自由饮水和采食矿物质块。以梯牧草为底物进行体外批次发酵，时长可达72小时，添加漆树提取物以达到最终浓度0、10、30、50、70和90 mg/L。
有效干物质（DM）降解率随提取物添加水平呈线性下降（p = 0.046）。从50 mg/L起始剂量开始，添加提取物后24至72小时的总产气量趋于下降（二次效应的显著性：24、48和72小时分别为p = 0.006、p<0.001和p = 0.008）。甲烷产量在24小时（p<0.05）和48小时（p<0.005）培养后随添加水平降低，50 mg/L剂量时最低。培养24小时后，漆树提取物增加了琥珀酸丝状杆菌的丰度（p<0.05）和黄化瘤胃球菌的丰度（p = 0.0597），并降低了产甲烷古菌的丰度（p<0.05）。
漆树被证明可减少甲烷产生并增加纤维素分解菌，且无任何毒性作用迹象，对DM降解性影响较小。
