Isolation,Identification and Drug Resistance Analysis of Yak Mastitis Pathogens
In March 2023,the mastitis disease was observed in a yak farm in Xining City,Qinghai Province.In order to determine the pathogenic agent of this disease,15 milk samples of confirmed mastitis cows were collected from the farm,and bacterial isolation and purification,and PCR identification were performed.The sensitivity of some pathogenic bacteria to antibiotics were analyzed via drug sensitivity test.The results showed that a total of 23 bacterial strains were isolated from 13 milk samples(86.67%,13/15),including Streptococcus agalactis(n =7),Staphylococcus aureus(n =8),Escherichia coli(n =4),Enterococcus faecalis(n =3),and Bacillus cereus(n = 1).Drug sensitivity tests were conducted on S.lactis,S.aureus,and E.coli,the results showed that all of the three pathogenic bacteria were highly or moderately sensitive to Streptomycin,Ciprofloxacin,Ofloxacin,Cefotaxime,and Cefradine.The results suggest that S.agalactiae,S.aureus,and E.coli are the main pathogens causing mastitis in the yak farm,and Cephalosporins and Enrofloxacin can be used as the preferred drugs for the prevention and con-trol of the disease.
Yak mastitisPathogenic bacteriaIsolation and identificationMixed infectionDrug sensitivity test