文献类型： 外文期刊

作者： Hu Hong-lian ¹ ; Yang Shu-qing ² ; Cheng Meng ² ; Song Li-wen ¹ ; Xu Ming ² ; Gao Min ¹ ; Yu Zhong-tang ³ ;

作者机构： 1.Inner Mongolia Acad Agr & Anim Husb Sci, Inst Anim Nutr & Feed, Hohhot 010031, Peoples R China

2.Inner Mongolia Agr Univ, Coll Anim Sci, Hohhot 010018, Peoples R China

3.Ohio State Univ, Dept Anim Sci, Columbus, OH 43210 USA

关键词： subacute ruminal acidosis; epithelial morphology; permeability; tight junction proteins; restitution

期刊名称：JOURNAL OF INTEGRATIVE AGRICULTURE （ 影响因子：4.384； 五年影响因子：4.021 ）

ISSN： 2095-3119

年卷期： 2022 年 21 卷 11 期

页码：

收录情况： SCI

摘要： Grain-induced subacute ruminal acidosis (SARA) impairs rumen epithelial barrier function, but it is yet to be determined if SARA can cause persistent damage to the morphology and function of the rumen epithelial barrier. The objective of the present study was to investigate if SARA has persistent effects on the morphological structure and permeability of ruminal epithelium and the expression of the genes involved in epithelial barrier function using a lactating goat model. Twelve mid-lactating Saanen goats with rumen cannulas were randomly assigned to 1 of 2 groups: control group (Ctrl, n=4) fed a basal diet with a non-fiber carbohydrate (NFC) to neutral detergent fiber (NDF) ratio of 1.40, and SARA group (SARA, n=8) fed the same basal diet but with increasing NFC to NDF ratio from 1.4 to 1.79, 2.31, and 3.23 overtime to induce SARA. At the end of the SARA challenge (post-SARA), 4 goats were randomly selected from the SARA group and fed only hay mixture ad libitum for another 4 weeks to allow for restitution (post-SARA). Ruminal pH was continuously recorded to monitor the severity of SARA. Samples of the ventral ruminal epithelium were collected after slaughter to examine the structural and functional changes of the ruminal epithelium using transmission electron microscopy (TEM), Ussing chambers, qRT-PCR, and Western bolt analyses. Compared with the Ctrl group, ruminal papilla length, width, surface area and thickness of stratum corneum increased (P<0.05), while stratum spinosum and basale thickness, and total depth of the epithelium decreased (P<0.05) in the SARA group. These changes diminished or tended to return to the levels of the Ctrl group in the post-SARA group (P>0.05). The SARA challenge also decreased cellular junction and widened the intercellular space between epithelial cells. Rumen transepithelial short-circuit current (Isc), tissue conductance (Gt), and mucosa-to-serosa flux of paracellular horseradish peroxidase (HRP) all increased (P<0.05) both in the SARA and post-SARA groups, which indicates that SARA can induce a sustained increase in epithelial permeability and barrier dysfunction. Moreover, the mRNA and protein expressions of CLDN1, OCLN and ZO-1 were down-regulated