绵羊亚急性瘤胃酸中毒对瘤胃上皮组织形态的影响OA北大核心CSTPCD

SARA(subacute ruminal acidosis)was used to observe the changes in the microstructure and ultrastructure of the rumen epithe-lium in sheep before SARA and after the treatment.Fifteen sheep in good condition were randomly divided into 2 groups:the normal(NG)group(n=5),and the subacute rumen acidosis(SARA)group(n=10).The NG group was fed with a whole-feed diet with a concentrate to forage ratio of 3∶7,and the SARA group was fed with a whole-feed diet with a concentrate to forage ratio of 7∶3.After successful induc-tion of the SARA model group,5 sheep in the SARA group were selected to be fed with a whole feed diet with a concentrate to forage ratio of 3∶7,and feeding for 25 days was defined as the recovery group(RG).At the end of the experiment,the animals were slaughtered,and the ventral and dorsal capsules of the rumen tissue were collected for paraffin section and transmission electron microscope to observe the morpho-logical and structural changes.The HE results showed that,compared with the NG and RG groups,the SARA group had partial exfoliation and thinning of the rumen papilla,abnormal morphology,severe keratinization,and thinning of the mucosal layer.The width of the dorsal capsule papilla and the thickness of the rumen epithelial mucosal layer in the SARA group were significantly lower than those in the NG group(P＜0.05).The thickness of stratum corneum was significantly higher than that in the NG and RG groups(P＜0.05).The results of trans-mission electron microscopy showed that,in the SARA group,most cells in the spinous process layer of the ventral and dorsal capsules of the rumen epithelium were necrotic,the cell membrane was ruptured and the cytoplasmic contents were lost,most mitochondria were pyknotic,the connections between cells were blurred,the structure was damaged,the number of cells was reduced,and the organelles were difficult to distinguish.Compared with the SARA group,the RG group had normal cell morphology and structure,complete and clear mitochondrial structure and a large number of mitochondria,and fuzzy desmosome connection between cells,but some desmosome connection structure was complete and the number was increased.In conclusion,subacute ruminal acidosis seriously affected the histological morphology of the ru-men epithelium in sheep and might affect the protective barrier of the rumen epithelium in them in the long term.