Isolation, Identification And Sensitive Drugs On Mycoplasma Ovipneumoniae

Mycoplasma pneumonia of sheep was a chronic infectious disease of respiratory tract caused by Mycoplasma ovipneumontae. In recent years, Mycoplasma ovipneumoniae was prevailing in a lot of countries and regions around the world, which caused huge economic loss. Mycoplasma ovipneumoniae Genome can only synthesis very little kinds of proteins and enzymes, so it was very difficult to culture in vitro and the reserched of such disease's reports were very little. The aim of this research was to isolate and identify the pathogen, and study the sensitivity tests of drugs. The aim was to find methods for controlling the disease in livestock production and veterinary clinic.Specimens were collected from sheep and goats with respiratory disease at Yaan cities. Through isolation and purification, the isolated strains were proved to be the same strain as the standard strain of M.ovipneumoniae Y98 by the identification of physical-chemical characteristics and serology. The results showed that the separating stock grew well when it was incubated in the mediums at 37℃, pH value 7.8. The concentration of horse serum were studied in this research. In the concentration of 20%, it can grows very well; it can't grow when the concentration was under 10%. At the first isolation and cultivation, it was better to cultivate in no-oxygen at 37℃, and the colonies were earlier to form. The colony has an appearace with typical nipple form. electron microscopy revealed separating stock had non-cell wall and the cell membrance was composed by three membrances, a large number of cells covered with an electron dense-stained amorphous material suggestion that it was a capsule consisted of cilias. There were a number of granulated ribosome in cytoplasm. Separating stock showed different shapes by negative staining to observe. For example, there were globular, silkiness, rhabditiform, bostrychoid and so on, they were 0.2～0.4um and the globular was their basic shape. Goats infected with the isolated strain indicated that it has significant pathogenicity for lamb, especially for more pure lamb. It was also has pathogenicity for adult-goat, but the pathogenicity was low.The effects of florfenicol, ciprofloxacin, tilmicosin, neomycin, azithromycin, erythromycin, ciprofloxacine, levofloxacin, tylosin, difloxacin, doxycycline and tiamulin on isolated strain in vitro were determined by two-fold dilution. Their minimal inhibitory concentrations(MIC) were respectively 0.1008±0.0349, 0.0385±0.0167, 0.0416±0.0180, 6.6612±2.3050, 0.0417±0.018, 1.2667±0.4388, 0.2054±0.0712, 0.3646±0.1263, 0.1917±0.0664, 3.2567±1.1281, 0.7415±0.2569, 0.0417±0.0144. These results concluded that ciprofloxacin, tilmicosin, azithromycin, tiamulinon are the most sensitive to Mycoplasma pneumonia. These results lay basis for the further development of new high efficacious and low-priced compound against mycoplasma pneumonia sheep and goats.