Long-term effect of subacute ruminal acidosis on the morphology and function of rumen epithelial barrier in lactating goats  

作　　者：HU Hong-lian YANG Shu-qing CHENG Meng SONG Li-wen XU Ming GAO Min YU Zhong-tang 

机构地区：[1]Institue of Animal Nutrition and Feed,Inner Mongolia Academy of Agriculture&Animal Husbandry Sciences,Hohhot 010031,P.R.China [2]College of Animal Science,Inner Mongolia Agricultural University,Hohhot 010018,P.R.China [3]Department of Animal Sciences,The Ohio State University,Columbus 43210,USA

出　　处：《Journal of Integrative Agriculture》2022年第11期3302-3313,共12页农业科学学报（英文版）

基　　金：supported by the National Natural ScienceFoundation of China(31472124);the Natural Science Foundation of Inner Mongolia,China(2019MS03031);the earmarked fund for China Agriculture Research System(CARS-36);the Innovation Fund of Inner Mongolia Agricultural and Animal Husbandry,China(2021CXJJM02);a China Scholarship Council(Beijing)fellowship to Hu Honglian for training at the Ohio State University,USA(201909150001)。

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 epithel

关 键 词：subacute ruminal acidosis epithelial morphology PERMEABILITY tight junction proteins RESTITUTION 

分 类 号：S827[农业科学—畜牧学]