Seroepidemiological Investigation And Pathogenic Identification Of Paratuberculosis In Sheep In Parts Of Inner Mongolia

Objective:aratuberculosis is a disease that mainly causes chronic infection or invisible infection of ruminants,and the disease has caused huge economic losses to the sheep industry.Inner Mongolia Autonomous Region is mainly known for animal husbandry,so it should pay more attention to every disease that harms animal husbandry.In recent years,the paratuberculosis of sheep has caused certain harm to the sheep breeding industry in the Inner Mongolia Autonomous Region,and has posed a serious threat to the high-quality sheep and breeding sheep industries.Therefore,this article carried out seroepidemiological investigation,pathogen molecular biological identification and isolation culture of sheep paratuberculosis in some areas of Inner Mongolia Autonomous Region,grasped the occurrence and pathogenic characteristics of the disease in parts of Inner Mongolia,and provided basis for the diagnosis and prevention of sheep paratuberculosis.Methods:lood samples from sheep in central,western,and eastern parts of Inner Mongolia were collected,serum was separated,and MAP antibodies were detected by ELISA;meanwhile,DNA was extracted from small bowel and lymph node tissue samples of suspected cases of paratuberculosis,using primers 16srRNA,IS900,f57,IS1311 DMC was amplified by PCR,and the resulting product was subjected to agarose gel electrophoresis test,and MAP typing identification was performed by amplifying gene fragments by DMC,sequencing and sequence analysis of gene fragment PCR products;after treatment of tissue disease materials,inoculation with specific culture medium Isolation,culture and identification of bacteria.Results:ccording to the results of epidemiological survey conducted by ELISA method,the positive rates of M.sheep paratuberculosis antibody in western,central and eastern Inner Mongolia were 2.89%,1.18%and 4.1%respectively;12 suspected paratuberculosis tissue samples passed the primer The PCR amplification and partial gene sequence analysis of IS900,f57 and IS1311 showed that all 12 cases were MAP positive.According to the typing primer DMC,7 cases were identified as M.paratuberculosis type C and 5 cases were S type;Cultivation of Zhou Zai yolk medium initially formed small sporadic colonies on the surface of the medium.The colonies were milky white particles.Picking colonies for PCR identification and acid-fast staining showed MAP positive.Conclusion:n some areas of Inner Mongolia,there is para-tuberculosis of sheep.The serological positive rate of para-tuberculosis of sheep in various counties is about 0%to 6.25%;there are two types of paratuberculosis sheep in the survey area:type C and type S,mainly type C;Mycobacterium paratuberculosis was cultured from tissue samples of suspected cases.