瘤胃中飼料的厭氧消化會產生揮發性脂肪酸（乙酸、丙酸和丁酸），這些脂肪酸是反芻動物的主要能量來源。該過程還會產生氣體副產物，包括二氧化碳（CO₂）和甲烷（CH₄），這些氣體會透過噯氣排出，是人為溫室氣體（GHG）排放的重要來源。調整粗飼料與精飼料（R:C）比例以及補充植物次級代謝物等日糧干預措施，是減少這些排放並維持動物生產力的有效策略。本研究探討了R:C比例以及添加無患子（Sapindus rarak，一種皂素和單寧的來源）對努比亞山羊生長性能、瘤胃參數和氣體排放的影響。在實驗1中，24隻努比亞女山羊被隨機分配到2×2多因子設計中，測試了兩種粗料與精料比例（70:30和30:70）以及兩種無患子添加量（0%和1%），試驗週期為8週。測量的參數包括攝食量(FI)、體增重(BWG)、飼料轉換率(FE)、瘤胃pH值、氨氮濃度、氧化還原電位（ORP）、導電率、總細菌數、原蟲數量以及氣體排放（產熱量、二氧化碳、甲烷、一氧化二氮和氨氣）。結果表明，高精料飼糧結合1%無患子添加可降低瘤胃pH值，改變氮代謝，減少總細菌數，減少產熱量和二氧化碳排放量，並提高體增重和飼料轉換率，從而實現最低的溫室氣體排放總量。實驗2採用2×2多因子設計，在四週內評估了無患子（0%和1%）和單寧（0.1%和0.3%）的添加效果。添加1%無患子降低了採食量和體增重，而添加0.3%單寧則改善了這兩個指標。兩種 添加劑均增加了瘤胃總細菌數，並降低了原蟲數量。無患子的添加降低了CO₂排放量，而單寧的添加則同時降低了CO₂和CH₄的排放量。添加0%無患子和0.3%單寧的組別中山羊的總產氣量最低。總之，透過調整飼糧組成和添加植物次級代謝物來調整飼糧，可以改善努比亞山羊的生長性能、調節瘤胃發酵，並降低溫室氣體排放。這些發現凸顯了此類策略在永續反芻動物生產中的潛力。
Anaerobic digestion of feed in the rumen generates volatile fatty acids (acetate, propionate, and butyrate), which serve as the primary energy source for ruminants. This process also produces gaseous by-products, including carbon dioxide (CO₂) and methane (CH₄), which are expelled via eructation and contribute substantially to anthropogenic greenhouse gas (GHG) emissions. Dietary interventions, such as adjusting roughage-to-concentrate (R:C) ratios and supplementing with plant secondary compounds, represent promising strategies to mitigate these emissions while sustaining animal productivity. The present study examined the effects of R:C ratios and supplementation with soapberry (Sapindus rarak), a source of saponins and tannins, on growth performance, rumen parameters, and gas emissions in Nubian goats. In Experiment 1, twenty-four female Nubian goats were allocated to a 2 × 2 factorial design, testing two R:C ratios (70:30 and 30:70) and two levels of soapberry supplementation (0% and 1%) over eight weeks. Measured parameters included feed intake (FI), body weight gain (BWG), feed efficiency
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