Effect of mixture of herbal plants on ruminal fermentation, degradability and gas production

ABSTRACT. Reducing livestock negative environmental impacts get great interest in last years. So, present study was carried out to determine the effect of adding different levels of mixture of thyme and celery versus salinomycin on ruminal fermentation, gas production, dry, organic matter and fiber degradation. Four experimental treatments were used by in-vitro batch culture technique, as follow: 60% CFM, 40% clover hay (control), control diet + 2.5 gm thyme + 2.5 gm celery kg-1 DM (T1), control diet + 5 gm thyme + 5 gm celery kg-1 DM (T2), control diet + 10 gm thyme + 10 gm celery kg-1 DM (T3), control diet + 0.4 gm Salinomycin kg-1 DM (T4). Ruminal pH value was significantly increased (p < 0.05) with T4 compared with other treatments. While, the T4 recorded the lowest value (p < 0.05) for microbial protein, short chain fatty acids concentrations (SCFA), total gas production, dry matter and organic matter degradability (DMd and OMd) compared with other treatments. Fiber fraction degradability (NDFd and ADFd) appeared no significant variance (p > 0.05) between control and other treatments except for T1 that recorded the lowest value (p < 0.05). It is concluded that mixture of thyme plus celery could be alternate for ionophores in the ruminant diets to enhance ruminal fermentation, reducing gas production without any negative effect on nutrients degradability.

摘要
近年来，降低畜禽养殖对环境的负面影响已成为研究热点。为此，本试验旨在探究添加不同水平百里香（thyme）与芹菜（celery）混合物，对比沙利霉素（Salinomycin），对瘤胃发酵、产气量、干物质、有机物及纤维降解的影响。本试验采用体外批式培养技术设置4组试验处理，具体如下：60% CFM + 40%三叶草干草（对照组）；基础日粮+2.5g百里香+2.5g芹菜·kg⁻¹干物质（Dry Matter, DM）（T1组）；基础日粮+5g百里香+5g芹菜·kg⁻¹干物质（T2组）；基础日粮+10g百里香+10g芹菜·kg⁻¹干物质（T3组）；基础日粮+0.4g沙利霉素·kg⁻¹干物质（T4组）。

与其余各组相比，T4组的瘤胃pH值显著升高（p<0.05）；而T4组的微生物蛋白、短链脂肪酸（Short Chain Fatty Acids, SCFA）浓度、总产气量、干物质降解率（DMd）与有机物降解率（OMd）均显著低于其余各组（p<0.05）。纤维组分降解率方面，中性洗涤纤维降解率（Neutral Detergent Fiber, NDFd）与酸性洗涤纤维降解率（Acid Detergent Fiber, ADFd）在对照组与其余各组间均无显著差异（p>0.05），仅T1组的纤维组分降解率显著最低（p<0.05）。

综上，百里香与芹菜的混合物可替代反刍动物日粮中的离子载体类添加剂，在提升瘤胃发酵性能、降低产气量的同时，不会对营养物质降解率产生负面影响。