Department of Animal Sciences, University of Florida, Gainesville, FL 32611.
Department of Animal Sciences, University of Florida, Gainesville, FL 32611; Department of Animal Science, Khon Kaen University, Khon Kaen 40002, Thailand.
J Dairy Sci. 2024 Feb;107(2):840-856. doi: 10.3168/jds.2023-23669. Epub 2023 Sep 18.
The objective of this study was to evaluate the effects of cashew nut shell extract (CNSE) and monensin on ruminal in vitro fermentation, CH production, and ruminal bacterial community structure. Treatments were as follows: control (CON, basal diet without additives); 2.5 μM monensin (MON); 0.1 mg CNSE granule/g DM (CNSE100); and 0.2 mg CNSE granule/g DM (CNSE200). Each treatment was incubated with 52 mL of buffered ruminal content and 500 mg of total mixed ration for 24 h using serum vials. The experiment was performed as a complete randomized block design with 3 runs. Run was used as a blocking factor. Each treatment had 5 replicates, in which 2 were used to determine nutrient degradability, and 3 were used to determine pH, NH-N, volatile fatty acids, lactate, total gas, CH production, and bacterial community composition. Treatment responses for all data, excluding bacterial abundance, were analyzed with the GLIMMIX procedure of SAS v9.4. Treatment responses for bacterial community structure were analyzed with a PERMANOVA test run with the R package vegan. Orthogonal contrasts were used to test the effects of (1) additive inclusion (ADD: CON vs. MON, CNSE100, and CNSE200); (2) additive type (MCN: MON vs. CNSE100 and CNSE200); and (3) CNSE dose (DOS: CNSE100 vs. CNSE200). We observed that pH, acetate, and acetate:propionate ratio in the CNSE100 treatment were lower compared with CNSE200, and propionate in the CNSE100 treatment was greater compared with CNSE200. Compared with MON, CNSE treatments tended to decrease total lactate concentration. Total gas production of CON was greater by 2.63% compared with all treatments, and total CH production was reduced by 10.64% in both CNSE treatments compared with MON. Also, compared with MON, in vitro dry matter degradabilities in CNSE treatments were lower. No effects were observed for NH-N or in vitro neutral detergent fiber degradability. Finally, the relative abundances of Prevotella, Treponema, and Schwartzia were lower, whereas the relative abundances of Butyrivibrio and Succinivibrio were greater in all treatments compared with CON. Overall, the inclusion of CNSE decreased CH production compared with MON, making CNSE a possible CH mitigation additive in dairy cattle diets.
本研究旨在评估腰果壳提取物（CNSE）和莫能菌素对体外瘤胃发酵、CH 生成和瘤胃细菌群落结构的影响。处理方法如下：对照（CON，不含添加剂的基础日粮）；2.5 μM 莫能菌素（MON）；0.1 mg CNSE 颗粒/克 DM（CNSE100）；和 0.2 mg CNSE 颗粒/克 DM（CNSE200）。每个处理都与 52 毫升缓冲瘤胃内容物和 500 毫克总混合日粮一起在血清小瓶中孵育 24 小时。该实验采用完全随机块设计，3 个运行。运行被用作一个分组因素。每个处理有 5 个重复，其中 2 个用于确定养分降解率，3 个用于确定 pH 值、NH-N、挥发性脂肪酸、乳酸、总气体、CH 生成和细菌群落组成。除细菌丰度外，所有数据的处理反应均采用 SAS v9.4 中的 GLIMMIX 程序进行分析。用 R 包 vegan 运行的 PERMANOVA 检验分析细菌群落结构的处理反应。使用正交对比检验（1）添加剂的包含（ADD：CON 与 MON、CNSE100 和 CNSE200 的对比）；（2）添加剂类型（MCN：MON 与 CNSE100 和 CNSE200 的对比）；和（3）CNSE 剂量（DOS：CNSE100 与 CNSE200 的对比）的影响。我们观察到，CNSE100 处理的 pH 值、乙酸和乙酸：丙酸比与 CNSE200 相比较低，而 CNSE100 处理的丙酸比 CNSE200 较高。与 MON 相比，CNSE 处理趋于降低总乳酸浓度。与所有处理相比，CON 的总气体生成量增加了 2.63%，与 MON 相比，CNSE 处理的总 CH 生成量减少了 10.64%。此外，与 MON 相比，CNSE 处理的体外干物质降解率较低。NH-N 或体外中性洗涤剂纤维降解率没有观察到影响。最后，与 CON 相比，所有处理中的普雷沃氏菌、密螺旋体和施瓦茨氏菌的相对丰度较低，而丁酸弧菌和琥珀酸弧菌的相对丰度较高。总的来说，与 MON 相比，CNSE 的 CH 生成量减少，这使得 CNSE 成为奶牛日粮中 CH 减排的一种可能添加剂。
