Changes in rumen fermentation and bacterial community in lactating dairy cows with subacute rumen acidosis following rumen content transplantation
Changes in rumen fermentation and bacterial community in lactating dairy cows with subacute rumen acidosis following rumen content transplantation
复制标题
亚急性瘤胃酸中毒泌乳奶牛瘤胃内容物移植后瘤胃发酵和细菌群落的变化
DOI：
10.3168/jds.2021-20490
复制
发表时间：
2021-09-20
影响因子：
3.5
通讯作者：
Mao, S. Y.
中科院分区：
文献类型：
--
作者：
Mu, Y. Y.;Qi, W. P.;Mao, S. Y.
瘤胃微生物群干预治疗瘤胃消化不良在生产中应用已久，近年来已成为研究热点。然而，它如何控制亚急性瘤胃酸中毒（SARA）奶牛瘤胃细菌稳态的重塑和瘤胃发酵的恢复，目前尚不清楚。本研究探讨了SARA奶牛瘤胃内容物移植（RCT）后瘤胃发酵和细菌群落的变化。整个实验分为SARA诱导期和随机对照期2个阶段。在SARA诱导期，选取12头瘤胃空心泌乳荷斯坦奶牛，随机分为2组，分别饲喂常规饲粮[CON；N = 4；40%精料，干物质（DM）基础]或高粒饲粮（HG; n = 8； 60%精料，DM基础）。SARA诱导期结束后，开始随机对照试验。将HG奶牛随机分为供受体组（DR）和自受体组（SR），在随机对照试验前将瘤胃内容物全部去除。DR组饲喂CON奶牛瘤胃内容物的70%，按可比体重配对；SR组每头奶牛瘤胃含量为70%，自产。结果表明，无论采用何种随机对照试验，移植第6 d后，瘤胃发酵各项参数基本恢复到SARA诱导前的正常水平。醋酸盐、戊酸盐和总挥发性脂肪酸（VFA）的浓度在SR奶牛中没有恢复，而在DR奶牛中全部恢复。扩增子测序结果表明，随机对照试验后4 d内，SR组和DR组瘤胃细菌稳态快速重建，DR组细菌群落多样性水平较高。在属水平上，与SR奶牛相比，DR奶牛未分类的瘤胃球菌科和糖化菌科比例更高。瘤胃细菌与瘤胃发酵的相关性分析表明，主要的移植敏感操作分类单位与VFA之间存在潜在的关系。共现网络分析显示，RCT只影响与其他类群相互作用弱的瘤胃细菌类群，而不影响共现水平高的关键瘤胃细菌。我们的研究结果表明，RCT有助于恢复患SARA奶牛瘤胃细菌稳态和瘤胃发酵，而不影响核心微生物组。
Rumen microbiota intervention has long been used to cure ruminal indigestion in production and has recently become a research hotspot. However, how it controls the remodeling of rumen bacterial homeostasis and the restoration of rumen fermentation in cows of subacute ruminal acidosis (SARA) remains poorly understood. This study explored changes in rumen fermentation and bacterial communities in SARA cows following rumen content transplantation (RCT). The entire experiment comprised 2 periods: the SARA induction period and the RCT period. During the SARA induction period, 12 ruminally cannulated lactating Holstein cows were selected and allocated into 2 groups at random, fed either a conventional diet [CON; n = 4; 40% concentrate, dry matter (DM) basis] or a high-grain diet (HG; n = 8; 60% concentrate, DM basis). After the SARA induction period, the RCT period began. The HG cows were randomly divided into 2 groups: the donor-recipient (DR) group and the self-recipient (SR) group, and their rumen contents were removed completely before RCT. For the DR group, cows received 70% rumen content from the CON cows, paired based on comparable body weight; for the SR group, each cow received 70% rumen content, self-derived. The results showed that nearly all rumen fermentation parameters returned to the normal levels that the cows had before SARA induction after 6 d of transplantation, regardless of RCT. The concentrations of acetate, valerate, and total volatile fatty acids (VFA) were not recovered in the SR cows, whereas all of them were recovered in the DR cows. The amplicon sequencing results indicated that both the SR and DR cows rebuild their rumen bacterial homeostasis quickly within 4 d after RCT, and the DR group showed a higher level of bacterial community diversity. At the genus level, the DR cows displayed an improved proportion of unclassified Ruminococcaceae and Saccharofermentans compared with the SR cows. Correlation analysis between the rumen bacteria and rumen fermentation suggested some potential relationships between the predominant transplantation-sensitive operational taxonomic units and VFA. Co-occurrence network analysis revealed that RCT affected only those rumen bacterial taxa that showed weak interactions with other taxa and did not affect the pivotal rumen bacteria with high levels of co-occurrence. Our findings indicate that RCT contributes to the restoration of rumen bacterial homeostasis and rumen fermentation in cows suffering from SARA without affecting the core microbiome.