Abstract

Rumen development is critical for the development of early lambs. This work aims to evaluate the effects of abrupt weaning at day 21 on rumen fermentation, histomorphological traits and the ruminal microbiota compared with continuous suckling. Twelve pairs of artificially reared full-sib neonatal male Hu lambs were allocated to two groups, one of which was weaned at day 21 (EW group) and the other which was not weaned (CON group). At day 26 and day 49, six lambs from each group were randomly selected and sacrificed to collect ruminal contents and rumen tissue samples. Results showed that weaning influenced the fermentation parameters in the rumen, and altered the microbial community composition on day 49 (p < 0.05). Several genera were associated with rumen fermentation parameters (p < 0.05). Volatile fatty acid (VFA) concentration is the key parameter impacting microbiota composition. Weaning influenced the expression of genes associated with VFA metabolism and regulation of cell proliferation (p < 0.05). In conclusion, weaning significantly influenced the morphological and functional development of the rumen, and bacterial community composition. The microbial community composition was strongly associated with rumen weight and fermentation profiles, but not with morphological development.

摘要

瘤胃发育对早期羔羊的发育至关重要。本工作旨在与连续哺乳相比，评估第 21 天突然断奶对瘤胃发酵、组织形态特征和瘤胃微生物群的影响。将12对人工饲养的全同胞新生雄性胡羔羊分为两组，一组在第21天断奶（EW组），另一组未断奶（CON组）。在第26天和第49天，每组随机挑选6只羔羊并处死，收集瘤胃内容物和瘤胃组织样本。结果表明，断奶影响瘤胃内的发酵参数，并改变了第49天的微生物群落组成（p  <0.05）。几个属与瘤胃发酵参数相关（p < 0.05)。挥发性脂肪酸（VFA）浓度是影响微生物群组成的关键参数。断奶影响VFA代谢相关基因的表达和细胞增殖调控（p  < 0.05）。总之，断奶显着影响瘤胃的形态和功能发育，以及细菌群落组成。微生物群落组成与瘤胃重量和发酵曲线密切相关，但与形态发育无关。