天津地区仔猪水肿病病原分离鉴定

Isolation and Identification of Pathogeny from Piglet Edema Disease in Tianjin

从天津地区分离鉴定猪水肿病大肠杆菌27株,并测定了分离株的部分生物学特性。鉴定结果表明,定型的23个分离株分属O139,O101,O138,O 108,O141,O147,O149,O 21,O8等9个血清型(4株未定型),其中O 139,O138,O101为优势血清型;10个试验菌株可以产生水肿毒素;11个强致病性菌株中,5株可产生明显溶血环,而16个弱致病性菌株均无溶血性。药敏试验结果表明,头孢氨苄的抑菌作用最强,但所有分离株均有不同程度的耐药性。

Through the experiments, 27 pathogenic strains of E. coli from edema disease of swine were isolated and identified, from different farms in Tianjin. Some biological characteristics were also determined, including pathogenicity for mice, O serogroups identification, edema toxin detection, blood-plate hemolysis and antibiotic sensitivity. 23 isolates belonged to 9 serotypes （4 unidentified）, O139, O138, O101 are predominant. Ten of strains may produce edema toxin. Within eleven strong pathogenicity isolates, five of them exhibited obvious hemolysis zone, while sixteen isolates with weak pathogenicity were negative for the test. Results of antibiotics sensitivity test described that Cefalexin had a strong antibacter action of E. coli, drug resistance was found for all isolated pathogens.