摘要
The objective of this study was to investigate the effects of live yeast (LY, Saccharomyces cerevisiae) on the lactation performance, bacterial community, and functions in the rumen and hindgut of dairy cows under heat stress. Thirty-three multiparous (parity 3.9 ± 0.8) Holstein dairy cows (189.1 ± 6.6 d in milk at the beginning of the experiment) were randomly assigned to three groups (11 cows per treatment). Cows in the three groups were fed a diet without yeast (CON), with 10 g yeast/d/head (LY-10), and with 20 g yeast/d/head (LY-20). The yeast product contained 2.0 × 1010 CFU/g. Supplementing LY decreased the rectal temperature and respiratory rate of cows, and increased dry matter intake, milk yield, milk fat yield, milk protein yield, and milk lactose yield (P P = 0.035). Interaction effects of treatment × week were observed for rectal temperature (P P P = 0.015), milk urea nitrogen (P = 0.001), milk protein yield (P = 0.008), and milk lactose yield (P = 0.030). In rumen, LY increased the concentrations of acetate, isobutyrate, isovaterate, valerate, total volatile fatty acids (VFAs), and NH3-N (P Prevotella and Prevotellaceae UCG-003 at the genus level with a series of enriched pathways in the metabolism of carbohydrates and protein. In fecal samples, LY did not affect the profile of VFAs (P > 0.05). Clostridium sensu stricto 1 (P = 0.013) and Actinobacillus (P = 0.011) increased in the relative abundance by LY, whereas Bacteroides (P = 0.016) and Oscillospirales UCG-010 (P = 0.005) decreased with a series of enriched pathways in carbohydrate metabolism, secondary bile acid biosynthesis. In summary, LY supplementation altered the bacterial community’s composition and function in rumen and hindgut, and simultaneously alleviated the detrimental effects of heat stress on dairy cows. These findings provide extended insight into the effects of LY in the rumen and hindgut of dairy cows exposed to heat stress.
摘要译文
这项研究的目的是研究活酵母（Ly，酿酒酵母）对乳头和热应激下奶牛的瘤胃和后肠的哺乳性性能，细菌群落和功能的影响。将33个多核心（3.9±0.8）荷斯坦奶牛（在实验开始时牛奶中的189.1±6.6 d）随机分配给三组（每次治疗11头母牛）。三组中的母牛没有酵母（CON），带有10 g酵母/D/头（LY-10），并带有20 g酵母/D/头（LY-20）。酵母产品包含2.0×10 10 cfu/g。补充LY可降低母牛的直肠温度和呼吸速度，并增加干物质摄入量，牛奶产量，牛奶脂肪产量，牛奶蛋白产量和牛奶乳糖产量（P P = 0.035）。观察到直肠温度（p p = 0.015），牛奶尿素氮（P = 0.001），牛奶蛋白产量（P = 0.008）和牛奶乳糖产率（P = 0.030）的治疗×周的相互作用效应。在瘤胃中，LY增加了乙酸，异丁酸酯，异丁酸，脱脂，瓣膜，总挥发性脂肪酸（VFAS）和NH 3 -N（P Prevotella和Prevotellaceae ucg -003在属中，属于代谢途径的一系列富集途径碳水化合物和蛋白质。在粪便样品中，LY不影响VFA（p> 0.05）的特征。p = 0.016）和振荡性UCG-010（p = 0.005）随着碳水化合物代谢的一系列富集途径，继发性胆汁酸生物合成的途径减少。总而言之，补充剂的补充剂改变了细菌社区的组成和功能，并同时确定了肿瘤和hindgut和hindgut，并改变热应激对奶牛的有害影响。这些发现提供了对Ly在暴露于热应激的奶牛的瘤胃和后肠影响中的影响。
Zihao Li [1]; Yang Fan [1]; Hao Bai [1]; Jiyou Zhang [1]; Shengyong Mao [1]; Wei Jin [1]. Live yeast supplementation altered the bacterial community’s composition and function in rumen and hindgut and alleviated the detrimental effects of heat stress on dairy cows[J]. Journal of Animal Science, 2023,101