Isolation, Identification And Detection Of Drug Resistance Of Duck Escherichia Coli In Zouping Region

In clinical veterinary, Colibacillosis can cause serverse hazardous, extraordinary avian Colibacillosis. Because this disease has complex clinical symptoms and diversification of pathology characteristic, it is a common disease puzzled by cultivates estate evolutionary. For the past few years, principal disease can basic control by intensive breed, but Colibacillosis can showed the upgrade tendency and it can become one of the chief bacteriosis in cultivate estate.In China, over 50 kinds of serotypes of avian pathogenic Escherichia coli have been reported. In the recent years, duck industry has developed quickly in Zouping region of Shandong province and the serious damage of duck colibacillosis follows naturally. To prevent and cure duck colibacillosis effectively, identification and drug-susceptibility analysis of duck pathogenic Escherichia coli were particularly important. This study includes three parts:Part one: Escherichia coli were isolated from diseased ducks from duck farms in Zouping region of Shandong provinceduring 2009, and 12 Escherichia coli isolates were characterized for O serotypes by serological identification. Four serotypes (O78, O35, O18 and O15) were were identified in the 12 Escherichia coli isolates, and the most common serotypes were O78 and O35 (58.35% and 25% respectively).Part two: Drug susceptibility determinations were used to test the isolated 12 Escherichia coli strains isolated from Zouping region by Kirby-Bauer method recommendation by WHO. The result showed that the Escherichia coli isolates had generally generated resistance to 17 kinds of drugs, highest degree to penicillin, tetracycline and rifampicin (most with inhibitory bacterium loop), higher degree to quinolones, but generally sensitive to amikacin, gentamycin and furadantin. Meanwhile, 83.33% ( 10/12 ) of bacterium had generated resistance to over 9 kinds of drugs.Part three: Owing to the strongest resistance to quinolones, gyrA and parC genes of the 12 Escherichia coli isolates were clond and sequenced. The result showed that mutations of gyrA and parC of most bacterium accord with the results of drug-susceptibility analysis except some ones, which indicated there were more complicated mechanism of resistance to quinolones in duck pathogenic Escherichia coli isolates in Zouping region.