Nunes H P B, Maduro Dias C S A M, Borba A E S
IITAA, Group of Agriculture and Animal Production of the University of the Azores, Rua Capitão d'Ávila, São Pedro, PT - 9700-042 Angra do Heroísmo, Açores - Portugal.
Heliyon. 2023 Jan 2;9(1):e12786. doi: 10.1016/j.heliyon.2022.e12786. eCollection 2023 Jan.
The inclusion of essential oils (EOs) in the diet of ruminants is one of the strategies used to alter ruminal microbial fermentation, improving feed efficiency, while simultaneously reducing enteric methane (CH) production. This study aimed to evaluate the effects of three new EOs from plants exotic to the Azores, (PU) (HG) and (CJ), on biogas production kinetics and CH production. Three levels of EOs (40, 80, and 120 μL/g dry matter (DM) were added to the basal diet to evaluate ruminal fermentation using the gas production technique. Added 800 mL of rumen inoculum with 5 g DM of the basal diet (BD) to all experimental units for 96 h, except for the blanks, to which only the inoculum was added. The total gas and CH produced by treatment incubation were recorded every hour after incubation until 96 h. The results showed that the gas production decreased significantly (P < 0.001) at 24 and 96 h after incubation, in the medium and high levels, with the essential oils PU, CJ, and HG treatment, when compared to the control treatment. The same significant differences (P < 0.001) were observed in CH production. The greatest reduction was noted with the addition of PUEO at the highest concentration (120 μL), which allowed a reduction in CH production at 24 h of 47% (P < 0.01). There was an interaction effect between EOs and concentration levels for all variables (P < 0.001). A decrease in total volatile fat acid (VFA) concentration (P < 0.05) was recorded compared to control, as well as the insoluble fraction and the potential degradation of the BD when EOs were included in the diet. In conclusion, the addition of EOs to the BD effectively reduced total enteric gas emissions and mitigated CH production. The most significant reduction of CH (47% in 24 h of incubation) occurs when 120 μL PUEO is added to each gram DM. The inclusion of OEs in the BD also affected the gas production kinetics and fermentation parameters.
在反刍动物日粮中添加精油是用于改变瘤胃微生物发酵、提高饲料效率并同时减少肠道甲烷（CH）排放的策略之一。本研究旨在评估来自亚速尔群岛外来植物的三种新精油（PU）（HG）和（CJ）对沼气生产动力学和CH排放的影响。将三种水平的精油（40、80和120微升/克干物质（DM））添加到基础日粮中，使用产气技术评估瘤胃发酵。向所有实验单元添加800毫升瘤胃接种物和5克DM的基础日粮（BD），培养96小时，空白组除外，空白组仅添加接种物。培养处理后每小时记录总气体和CH产量，直至96小时。结果表明，与对照处理相比，在培养24小时和96小时后，中高水平的精油PU、CJ和HG处理组的产气量显著降低（P<0.001）。CH排放也观察到相同的显著差异（P<0.001）。添加最高浓度（120微升）的PUEO时CH排放减少最多，在24小时时CH排放减少47%（P<0.01）。所有变量的精油和浓度水平之间存在交互作用（P<0.001）。与对照相比，日粮中添加精油时，总挥发性脂肪酸（VFA）浓度降低（P<0.05），同时BD的不溶性部分和潜在降解也降低。总之，向BD中添加精油有效地减少了总肠道气体排放并减轻了CH排放。当每克DM添加120微升PUEO时，CH排放减少最为显著（培养24小时时减少47%）。在BD中添加OE也影响了产气动力学和发酵参数
