120株奶牛乳腺炎流行病原菌的分类和耐药谱分析

The Classification of the 120 Strains of Mastitis Epidemic Pathogens in Dairy Cows and the Spectrum Analysis of Their Drug Resistance

目的通过对流行于四川成都、眉山和绵阳的奶牛乳腺炎病原菌进行分类和耐药性分析,为奶牛乳腺炎的临床合理用药提供科学依据。方法采用K-B法测定了临床分离的120株奶牛乳腺炎病原菌对青霉素、链霉素、四环素、红霉素、庆大霉素、喹诺酮类、头孢噻吩和头孢噻肟8种抗生素的药物敏感性。结果 120株奶牛乳腺炎病原菌中91株病原菌表现为耐药,耐药率为75.8%,大部分病原菌耐受1种(34.0%)或2种抗生素(33.0%)。病原菌对8种抗生素的敏感性与临床用药规律呈一定的相关性,其中分离病原菌对青霉素和链霉素的耐药率最高,分别为65.2%和64.8%;其次为四环素和红霉素,耐药率分别为26.7%和30.3%;对环丙沙星的敏感性最好,敏感率为89.2%,提示其为该地区治疗奶牛乳腺炎的有效药物。结论该地区奶牛乳腺炎病原菌以葡萄球菌和大肠埃希菌最为常见,所试奶牛乳腺炎病原菌耐药率高,部分菌株表现为多重耐药,提示应合理规范使用抗生素,减缓耐药菌株的产生。

Objective To classify the epidemic pathogens of mastitis in dairy cows among the cities of Sichuan Province including Chengdu, Meishan and Mianyang and analyze their drug resistance for the purpose of providing the scientific basis for the rational drug use in treating cow mastitis. Methods 120 strains of pathogenic bacteria were isolated from the milk of dairy cows suffering from mastitis and the K-B method was used to detect their drug sensitivity to 8 antibiotics including penicillin, streptomycin, tetracycline, erythromycin, gentamicin, quinolones, cefoxitin and cefotaxime. Results The results showed that 91 strains out of the 120 strains were resistant to those antibiotics and the resistance rate was 75. 8%. Most of the pathogenic bacteria were resistant to one or two antibiotics, and the resistance rates were 34.0% and 33.0% respectively. There was a certain correlation between the sensitivity of the pathogenic bacteria to the 8 antibiotics and the regularity of clinical use in treating cow mastitis. The pathogenic bacteria were the most resistant to penicillin and streptomycin with the resistance rates of 65.2% and 64.8%, which were followed by the resistance rates to tetracycline and erythromycin, which were 26.7% and 30.3%. The sensitivity to ciprofloxacin was the highest with the rate of 89.2%, which indicated that it was an effective drug in treating cow mastitis. Conclusion Staphylococcus and Escherichia coli are the most common in the pathogenic bacteria isolated from the milk of dairy cows suffering from mastitis. The resistance rate of the pathogenic bacteria are very high and some strains show multidrug resistance, which indicates that the antibiotics should be used rationally to reduce the emergence of drug-resistant strains.