摘要
A major goal in dairy research is to improve milk production efficiency (MPE). With the advent of next-generation sequencing, efforts are underway to improve MPE by manipulating the rumen microbiota. MPE correlates to ruminal bacterial community composition (BCC), but the adult rumen microbiota is highly stable and returns to a baseline BCC after heavy perturbation. We seek to influence rumen BCC by early intervention in pre-weaning calves. Two cannulated Holstein donors of disparate MPE were selected. Three cohorts of 6 bull calves were established and dosed by gavage with a rumen inoculum sourced from the high-efficiency donor (HE), the low-efficiency donor (LE), or an autoclaved 50:50 mix as a microbe-free control (C). Dosing occurred at birth, then biweekly through 6 weeks. Feces were collected at each dosing. Daily preweaning intake of calf starter, which correlates to downstream feed efficiency, was greatest in HE calves and lowest in C calves (P < 0.05), though preweaning average daily gain did not differ between cohorts (P = 0.210). Calves were sacrificed at 8 weeks to access rumen contents and rumen wall sections were collected to assess papillation. Fecal and rumen samples were subjected to 16S rRNA amplicon sequencing. BCC differed by cohort in fecal and rumen samples (P < 0.05), with HE calf samples most similar to adult rumen samples and C calves least similar. Additionally, HE calves tended to have elongated papillae (P =0.062), the development of which is dependent on byproducts of microbial metabolism in the rumen and which points to differences in potential absorptive capacity of the epithelium. These data demonstrate that the rumen BCC can be influenced by early intervention. Future work includes expansion of this dosing protocol to a cohort of 60 female calves, following rumen BCC development and the impact on MPE in through the first lactation.
摘要译文
乳制品研究的主要目标是提高牛奶生产效率（MPE）。随着下一代测序的出现，正在努力通过操纵瘤胃微生物群来改善MPE。 MPE与瘤胃细菌群落组成（BCC）相关，但是成年瘤胃微生物群高度稳定，并在扰动后返回基线BCC。我们试图通过早期干预预性犊牛来影响瘤胃BCC。选择了两个不同MPE的霍尔斯坦供体。建立了三只群6个牛犊的队列，并通过烤肉进行了剂量，并用瘤胃接种物采购了高效供体（HE），低效率供体（LE）或高压灭菌的50:50混合物（作为无微生物对照）（ C）。剂量发生在出生时，然后每两周至6周。每次剂量收集粪便。小腿启动器的每日摄入量与下游饲料的效率相关，在犊牛中最大，在C犊牛中最低（p <0.05），尽管队列之间的平均每日增益没有差异（p = 0.210）。在8周时处死小牛以获取瘤胃含量，并收集瘤胃壁切片以评估乳头状。粪便和瘤胃样品进行16S rRNA扩增子测序。 BCC在粪便和瘤胃样品中的队列有所不同（p <0.05），而他的小动脉样品与成年瘤胃样本最相似，而C犊牛最不相似。此外，他的犊牛倾向于拉长乳头（p = 0.062），其发育取决于瘤胃中微生物代谢的副产品，并指出上皮细胞潜在吸收能力的差异。这些数据表明，瘤胃BCC可能受到早期干预的影响。未来的工作包括将这种给药方案扩展到瘤胃BCC发育后的60个女犊牛的队列，并通过第一次泌乳对MPE的影响。
Madison S Cox; Paul J Weimer; ;rew J Steinberger; Joseph H Skarlupka; ; Garret Suen. 166 Altering the ruminal microbiota in dairy calves using rumen contents dosing[J]. Journal of Animal Science, 2020,98(Sup4): 135-136