The study aimed to determine the effects of a postbiotic feeding program consisting of liquid and dry Saccharomyces cerevisiae fermentation product (SCFP) on ruminal fermentation, digestibility, and plasma metabolome of Holstein steers receiving a grain-based diet. Eight Holstein steers (body weight, BW, 467 ± 13.9 kg) equipped with rumen cannulas were used in a crossover design study, with 21 d per period and a 7-d washout period in between periods. Steers were stratified by initial BW and assigned to 1 of 2 treatments. The treatments were 1) Control, basal finishing diet only (CON); 2) SCFP, 1-d feeding of liquid SCFP (infused into the rumen via the cannula at 11 mL/100 kg BW) followed by daily feeding of dry SCFP (12 g/d, top-dressed). Feed and spot fecal samples were collected during days 17 to 20 for determination of digestibility and fecal excretion of N, P, Cu, and Zn. Digestibility was measured using acid-insoluble ash as an internal marker. Blood samples were collected on day 21 before the morning feeding. Rumen fluid samples were collected on days 0, 1, 2, 3, 5, and 21 via rumen cannula. Results were analyzed with the GLIMMIX procedure of SAS 9.4 (SAS, 2023). Treatment did not affect dry matter intake (P = 0.15) and digestibility (P ≥ 0.62). The fecal output and absorption of Zn, Cu, P, and N were not affected (P > 0.22) by treatment. On day 1, the liquid SCFP supplementation tended to reduce (P = 0.07) ruminal VFA concentration and increased (P < 0.01) the molar proportion of valerate. Feeding SCFP tended to increase total ruminal VFA on day 5 (P = 0.08) and significantly increased total VFA on day 21 (P = 0.05). Ruminal NH3–N was reduced (P = 0.02) on day 21 by supplementing SCFP. Treatment did not affect the production of proinflammatory cytokines, interleukin (IL)-1β (P > 0.19), and IL-6 (P > 0.12) in the whole blood in response to various toll-like receptor stimulants in vitro. Feeding SCFP enriched (P ≤ 0.05) plasma metabolic pathways, including citric acid cycle, pyrimidine metabolism, glycolysis/gluconeogenesis, retinol metabolism, and inositol phosphate metabolism pathways. In summary, supplementing liquid SCFP with subsequent dry SCFP enhanced ruminal total VFA production and reduced NH3–N concentration in the rumen. Furthermore, feeding SCFP enriched several important pathways in lipid, protein, and glucose metabolism, which may improve feed efficiency of energy and protein in Holstein steers.

中文翻译：

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液体和干燥酿酒酵母发酵产物饲喂计划对接受谷物饮食的荷斯坦阉牛瘤胃发酵、总消化道消化率和血浆代谢组的影响


该研究旨在确定由液体和干酿酒酵母发酵产物 （SCFP） 组成的后生元喂养计划对接受谷物饮食的荷斯坦公牛的瘤胃发酵、消化率和血浆代谢组的影响。8 头配备瘤胃插管的荷斯坦阉牛 （体重，体重，467 ± 13.9 kg） 用于交叉设计研究，每个时期 21 天，月经之间 7 天清除期。按初始 BW 对阉牛进行分层，并分配到 2 种处理中的 1 种。处理是 1） 对照，仅基础育肥饮食 （CON）;2） SCFP，1 天饲喂液体 SCFP（通过套管以 11 mL/100 kg 体重注入瘤胃），然后每天饲喂干 SCFP（12 g/d，追肥）。在第 17 至 20 天收集饲料和现场粪便样品，以确定 N、P、Cu 和 Zn 的消化率和粪便排泄量。使用酸不溶性灰分作为内部标志物测量消化率。在早晨喂养前第 21 天采集血样。在第 0 天、第 1 天、第 2 天、第 3 天、第 5 天和第 21 天通过瘤胃插管收集瘤胃液样本。使用 SAS 9.4 的 GLIMMIX 程序分析结果 （SAS， 2023）。处理不影响干物质摄入量 （P = 0.15） 和消化率 （P ≥ 0.62）。处理对粪便排出量和 Zn 、 Cu 、 P 和 N 的吸收没有影响 （P > 0.22）。第 1 天，液体 SCFP 补充剂倾向于降低 （P = 0.07） 瘤胃 VFA 浓度并增加 （P < 0.01） 戊酸盐的摩尔比例。饲喂 SCFP 倾向于增加第 5 天瘤胃总 VFA （P = 0.08），第 21 天显着增加总 VFA （P = 0.05）。通过补充 SCFP 在第 21 天降低瘤胃 NH3-N （P = 0.02）。 治疗不影响全血中促炎细胞因子、白细胞介素 （IL）-1β （P > 0.19） 和 IL-6 （P > 0.12） 的产生，以响应体外各种 toll 样受体兴奋剂。饲喂富含 SCFP （P ≤ 0.05） 的血浆代谢途径，包括柠檬酸循环、嘧啶代谢、糖酵解/糖异生、视黄醇代谢和肌醇磷酸代谢途径。总之，在液体 SCFP 中补充随后的干 SCFP 可增加瘤胃总 VFA 的产生并降低瘤胃中的 NH3-N 浓度。此外，饲喂 SCFP 富集了脂质、蛋白质和葡萄糖代谢的几个重要途径，这可能会提高荷斯坦公牛能量和蛋白质的饲料效率。