Abstract: Dairy cow mastitis is one of the major serious diseases in dairy farming industry world wide since its significant impact on economics,dairy farming and human health.More and more study focus on its pathogenesis,diagnosis,prevention,and so on.Our review based upon the recent progress on mastitis pathogen,one of the major causes of dairy cow mastitis and try to know the relationship among infection type,dairy cow and pathogen and pathogen themselves.The development of mastitis in dairy cows is due to many factors,such as invasion of pathogenic bacteria,the capability of cow defence system,the response of breast to pathogen,the synergism or repressive interaction among pathogenic bacteria.Staphylococcus aureus is well-known main infectious pathogen of dairy cow mastitis.It is very hard to cure in dairy cow body and has widespread drug resistance due to its unique biological characteristics.Streptococcus agalactiae belongs to an infectious or environmental pathogen is not definitive so far.It does cause high infection rate in our dairy cow farming.This kind of disease has relative higher cure rate comparing to other pathogenic bacteria since it is sensitive to many antibiotics.Escherichia coli is known as an environmental pathogen,it was detected in many cow mastitis isolates.However,the effect of antibiotics treatment on it requires further investigation since its drug resistance is common exist and becoming more severe.Mycoplasma bovis is one of the world wide infectious pathogens.Its infection rate has risen during past ten years.There is a overall poor therapeutic effect on it and it is difficult in vaccine development.Furthermore its drug resistance is still increasing.This review focused on the recent progresses of epidemiology,disease and prevention of the major cow mastitis pathogens,in order to help researchers in the field of dairy farm management and scientific study.

Key words: dairy cow mastitis; pathogenic bacteria; infection; prevalence; antibiotic resistance