Liquid hot water (LHW) treatment can be used to disrupt the fiber structure of rice straw. This in vitro ruminal batch culture study investigated the effect of LHW treatment on feed degradation, methane (CH4) production, and microbial populations. Rice straw was treated by LHW, and in vitro ruminal fermentation was performed using an automatic system with 72 h of incubation. Scanning electron microscopy showed that LHW treatment disrupted the physical structure of rice straw. Liquid hot water treatment decreased neutral detergent fiber and hemicellulose contents of the rice straw and increased neutral detergent solubles, water-soluble carbohydrates, and arabinose contents. Liquid hot water treatment increased dry matter degradation and volatile fatty acid concentration and decreased the acetate:propionate ratio, CH4 production, hydrogen accumulation, neutral detergent fiber degradation, and populations of protozoa, fungi, and cellulolytic bacteria. In summary, LHW treatment disrupted the cellulose-hemicellulose-lignin structure matrix of rice straw, leading to increased substrate degradability and decreased CH4 production. Therefore, the LHW treatment is a potential strategy to improve the nutritive value of forage such as rice straw and decrease the CH4 emissions in ruminants.

中文翻译：

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稻草的液体热水处理可增强体外瘤胃发酵过程中的厌氧降解并抑制甲烷的产生。

液态热水（LHW）处理可用于破坏稻草的纤维结构。这项体外瘤胃批量培养研究研究了LHW处理对饲料降解，甲烷（CH4）产生和微生物种群的影响。用LHW处理稻草，并使用72小时温育的自动系统进行体外瘤胃发酵。扫描电子显微镜显示，LHW处理破坏了稻草的物理结构。液体热水处理减少了稻草的中性洗涤剂纤维和半纤维素含量，并增加了中性洗涤剂的可溶性物质，水溶性碳水化合物和阿拉伯糖含量。液态热水处理增加了干物质的降解和挥发性脂肪酸的浓度，并降低了乙酸根与丙酸根的比例，CH4的产生，氢积累，中性洗涤剂纤维降解以及原生动物，真菌和纤维素分解细菌的种群。总之，LHW处理破坏了稻草的纤维素-半纤维素-木质素结构基质，导致底物降解性增加和CH4产量降低。因此，LHW处理是提高草料（如稻草）的营养价值并减少反刍动物CH4排放的潜在策略。