Studies On The Infection Of Mycoplasma Ovipneumoniae In Sheep At Intensive Farms In Part Of Xinjiang

Objective: To survey the Mycoplasma ovipneumoniae(MO)infection and find out the major pathogen of the lamb s which caused epidemic outbreak of disease in intensive sheep farm from part area of Northern Xinjiang.For the region's sheep contagious pleuropneumonia immune prevention and control to provide the scientific basis.Methods: A total of 67 serum samples,68 nasal swabs and 6 lungs tissue were collected from five large-scale farms in five regions(Qitai,Manasi,Wujiaqu,Shihezi,and Kashi)from 2015 to 2016,and stored at-20 °C.The dynamic changes of MO and MP antigen antibody of sera from infected lambs were detected by Mycoplasma ovipneumoniae(MO)commercial kits,sheep Mycoplasma pneumoniae(MP)commercial kits,double antibody enzyme linked immunosorbent assay(ELISA)and indirect ELISA.The Mycoplasma ovipneumoniae isolates were identified by colony morphology,specific PCR,growth inhibition test(GIT)and susceptibility test,seven isolates were cloned and sequenced.Results: 1.Sheep infected MO in five regions of five large-farms in Xinjiang,MO-Ag positive rate was ranged between 26.66% to 100%,MO-Ab positive rate lied in 46.66%-46.66%,MO-Ag positive rate was 100% in three sheep farms.The sheep was averaging detection MP antigen and antibody positive,but the positive rates was lower than the MO,and there was MO and MP dual infection in sheep.2.Lamb infected nasal swabs MO PCR positive rate was 68.75%-100% in five regions five large-scale sheep farm,positive rate was100%,the two sheep field and MO ELISA test results are basically identical.Small tail han sheep,Suffolk sheep and without obvious difference,but the two sheep field at Manas and Wujiaqu MO positive rate was higher than other regions.3.From the lamb infected of nasal swabs and 9 strains were isolated by typical MO in the lung tissue,based on PCR identification of MO 16 s rRNA sequences were amplified the size of 406 bp,the nucleotide homology analysis,9 strains of isolates with Y98 homology were above 75%.Conclusion: 1.Sheep infected Mycoplasma pneumoniae and were at a high level in intensive sheep farm from part area of Northern Xinjiang.2.From pneumonia infection sheep serum detection MP antigen and antibody,its may MP infected.3.Among different regions,different areas variety,MO infection rate had no obvious difference,Suffolk sheep infection rate was lower than the Small-tailed Han sheep and Hu-sheep.Breeding density,the number of sheep field positive rate is higher.4.Lamb infected MO and Y98 standardstrains isolated nucleotide homology was higher from large-farms.