江西部分地区临床健康猪群中副猪嗜血杆菌的血清型鉴定及耐药性调查

Serotyping and Drug Resistance of Haemophilus parasuis in Clinically Healthy Pigs in Some Areas of Jiangxi Province

【目的】调查江西省部分地区临床健康猪群中副猪嗜血杆菌的优势血清型及耐药现状。【方法】2018—2019年从江西几个规模化猪场的临床健康猪群中采集114份鼻腔棉拭子,通过菌落形态观察和PCR方法分离副猪嗜血杆菌,进行血清分型鉴定,应用Kerby-Bauer纸片扩散法测定分离菌株对17种抗生素的耐药性。【结果】共检出13株副猪嗜血杆菌,检出率为11.40%;通过PCR的方法确定江西省地区流行的优势菌株为血清13型,占比46.15%,其次分别是不可分型菌株(38.46%)、血清5型(7.69%)和血清11型(7.69%);13株副猪嗜血杆菌分离株对氨基糖苷类抗菌药(卡那霉素、链霉素)、大环内酯类抗菌药(麦迪霉素)、氨苄西林、哌拉西林耐药率较高,而对喹诺酮类抗菌药(氧氟沙星)和头孢类抗菌药敏感率可达100%;多重耐药现象突出,以3重、4重耐药菌株为主。【结论】江西省部分地区规模化猪场当前流行的副猪嗜血杆菌优势血清型为13型,头孢类、喹诺酮类抗菌素是防控副猪嗜血杆菌病发生的有效药物。目前副猪嗜血杆菌的耐药情况比较严重,猪场应多方面做好副猪嗜血杆菌的防控工作,建立完善合理的细菌病防控方案。

[Objective]This study was performed for investigating the prevalent serotypes and drug resistance of Haemophilus parasuis present in Jiangxi Province,China.[Method]114 nasal swabs were collected from clinically healthy pigs from several large-scale pig farms in Jiangxi Province from 2018 to 2019.The identification and serotyping of H.parasuis isolates were identified by PCR assays.The resistance profiles of the isolates to 17 kinds of antibiotics were determined by the Kerby-Bauer method[.Result]Results showed that 13 of H.parasuis isolates were identified with the positive isolation rate of 11.40%.PCR assays showed that the most prevalent serotype in this study were serotype 13 with a proportion of 46.15%,followed by the non-classifiable strains(38.46%),serotype 5(7.69%)and serotype 11(7.69%).Thirteen H.parasuis isolates were highly resistant to aminoglycosides(kanamycin and streptomycin),macrolides(medicin),ampicillin,and piperacillin,but were sensitive to quinolones(ofloxacin)and cephalosporins with the sensitivity rates of 100%.The phenomenon of multi-drug resistance was observed.Most of these isolates showed resistance to 3 or 4 kinds of antibiotics.[Conclusion]These results revealed that the most common serotype of H.parasuis in these large-scale pig farms was serotype 13.Cephalosporins and quinolones were effective drugs for the prevention and control of H.parasuis infection.At present,multi-drug resistance for H.parasuis isolates is serious.Effective prevention and control strategies of H.parasuis infection are needed to be performed from many aspects to establish a reasonable anti-infection system.