Abstract The overall objective of the current study was to evaluate the effects of 2 carriers (Silica, SIL, and Tween 80, T80) and their interaction with 8 phytochemicals (PCs), on in vitro dry matter and neutral detergent fibre digestibility (DMD, NDFD) of 3 substrates commonly used as feed for dairy cattle (soybean meal, maize meal and total mixed ration –TMR). A total of eight PCs were tested: 4 essential oils (EO) - cinnamon oil (CIN), clove oil (CLO), thyme oil (THY) and oregano oil (ORE) - and 4 essential oil active compounds (EOAC) - cinnamaldehyde (CIN-AC), eugenol (EUG), thymol (THY-AC) and carvacrol (CAR). A positive control with carrier and no PCs was tested for each substrate (CRR). Each PC was tested at 0.5 mg L−1 of medium on DMD and NDFD in an in vitro batch fermentation system. The incubation was performed twice at the intervals of 4 (DMD4, NDFD4) and 24 (DMD24, NDFD24) h. The PCs effect was significant on maize meal and soybean meal DMD24. The carrier’s effect was significant on soybean meal DMD24, indicating a depressive effect of T80 on soybean meal. The PC-carrier interactions were significant on both DMD and NDFD of the tested substrates, except for maize meal and soybean meal DMD24. The PCs-SIL combinations generally increased digestibility while the combination with T80 exerted positive effect only on maize DMD4. The PC-carrier combinations variably affect digestibility of different substrates and these interactions should be considered both for their scientific and commercial implications. HIGHLIGHTS PC-Carrier interactions affect in vitro digestibility. In general, the PC-SIL combinations increase digestibility while those with Tween 80 exert depressing effect. The PC-Carrier effect is variable depending on the degraded substrate.

中文翻译：

---

选定的植物化学物质与载体二氧化硅和吐温 80 的组合对普通饲料的干物质和中性洗涤纤维消化率的影响

摘要 本研究的总体目标是评估 2 种载体（二氧化硅、SIL 和吐温 80、T80）及其与 8 种植物化学物质 (PC) 的相互作用对体外干物质和中性洗涤纤维消化率 (DMD、 NDFD) 的 3 种底物通常用作奶牛饲料（豆粕、玉米粕和全混合日粮 –TMR）。总共测试了八种 PC：4 种精油 (EO) - 肉桂油 (CIN)、丁香油 (CLO)、百里香油 (THY) 和牛至油 (ORE) - 以及 4 种精油活性化合物 (EOAC) - 肉桂醛(CIN-AC)、丁香酚 (EUG)、百里酚 (THY-AC) 和香芹酚 (CAR)。对每种底物 (CRR) 测试了带有载体且无 PC 的阳性对照。在体外分批发酵系统中，在 DMD 和 NDFD 上以 0.5 mg L-1 培养基对每个 PC 进行测试。孵育以 4 (DMD4, NDFD4) 和 24 (DMD24, NDFD24) h 的间隔进行两次。PCs 对玉米粉和豆粕 DMD24 的影响显着。载体对豆粕DMD24的影响显着，表明T80对豆粕有抑制作用。除玉米粉和豆粕 DMD24 外，PC-载体相互作用对测试基质的 DMD 和 NDFD 均显着。PCs-SIL 组合通常会增加消化率，而与 T80 的组合仅对玉米 DMD4 产生积极影响。PC-载体组合对不同底物的消化率有不同的影响，这些相互作用应考虑其科学和商业意义。亮点 PC-载体相互作用影响体外消化率。一般来说，PC-SIL 组合可提高消化率，而含有吐温 80 的组合则具有抑制作用。PC-Carrier 效应因降解的底物而异。