Abstract: Mycoplasma synoviae (MS) can cause poultry respiratory diseases, avian onfectious synovitis, eggshell apex abnormalities and growth retardation etc, brings huge economic losses to the global poultry industry.MS has no cell wall, only one serotype, isolation and culture requirements are demanding, the genome is smaller than bacteria, it has strong antigen mutation ability, and a variety of membrane proteins are related to immune response and cell adhesion.MS is host-specific and mainly affects young chickens and turkeys.It can be transmitted horizontally and vertically and is distributed worldwide.MS adheres to host cells through membrane proteins, releases toxic products, immune evasion, grabs nutrients etc, resulting in host cell damage or death.MS inactivated vaccine has high safety and protection rate, which can prevent it from colonizing in air sacs and trachea.Live vaccines cannot protect infected chickens, and will induce disease or aggravate symptoms after vaccination.Genetic engineering vaccines are highly safe and easy to mass produce, and will be the future direction of MS vaccine research and development.Macrolides, tetracyclines and other drugs combined vaccines have the best immunization effects, and there are differences in MS resistance in different countries and regions.Based on the problems in the prevention and treatment of MS, the development of new high-efficiency vaccines and antibiotic substitutes that can break through the interference of maternal antibodies and antibiotics will be the focus of future work.The author introduced the pathogenic characteristics, epidemic characteristics, domestic and international epidemic status, laboratory diagnosis methods and pathogenic mechanism of MS, focusing on MS vaccine immunization and drug control, and finally looked forward to the future development trend of the disease control.

Key words: chicken; Mycoplasma synoviae; epidemic status; vaccine; drug