Abstract: [Objective] To explore the incidence pattern of bovine mastitis in Linyi City,and provide theoretical and practical basis for the scientific and effective prevention and control of bovine mastitis in the city. [Method] Conduct a survey and statistics on the incidence of mastitis in 22 large-scale ranches （cooperatives） in the city from January to December 2023. [Result] The incidence rate of clinical mastitis and subclinical mastitis were 16.2% and 28.5% respectively. Under the two feeding modes of large-scale breeding and cooperative breeding,the cooperative breeding mode has a higher incidence rate of clinical mastitis,subclinical mastitis and blind nipple. The incidence rate in winter （November to January of the next year） is higher than that in other seasons. The incidence rate of mastitis increases with the increase of parity and age. The main pathogenic bacteria for latent mastitis in dairy cows in the city are Escherichia coli and Staphylococcus aureus. Among them, Escherichia coli is sensitive to cephalosporins such as ceftriaxone and cefradine,tetracyclines such as doxycycline and doxycycline,and penicillins such as ampicillin and amoxicillin. Staphylococcus aureus is sensitive to cephalosporin antibiotics such as cefradine and ceftriaxone,as well as penicillin antibiotics such as amoxicillin and ampicillin. [Conclusion] It is recommended that large-scale ranches （cooperatives） in the city strengthen cattle hygiene management,nipple disinfection,improve environmental hygiene in cowsheds,beds,bedding,milking parlors,etc.,strengthen management during the dry milk period,select high-sensitivity drugs to timely and effectively control subclinical mastitis,actively seek alternative therapies,improve prevention and control measures,and enhance treatment effectiveness.

Key words: dairy cow, mastitis, disease incidence, investigation, analysis