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Avian colibacillosis (Avian colibacillosis) by Avian pathogenic Escherichia coli (Avian pathogenic Escherichia coli, APEC) caused by local or systemic infection of the disease, avian salmonellosis (Salmonellosis avium) is made in any of Salmonella one or more members of a large group of birds caused by acute or chronic diseases, both of which are common poultry diseases prevention and control difficult. Quinolones as a clinical antimicrobial drugs most commonly used one of the antibiotic selection pressure, its becoming more resistant bacteria, which has become a serious public health problem. This study aimed to collect different regions, different times and different groups of isolates based on the understanding in some regions of avian Escherichia coli and Salmonella on 1-4 behalf of 10 kinds of quinolone resistance situation, preliminary study of plasmid-mediated The quinolone resistance mechanisms. 1 Avian Escherichia coli and Salmonella resistant to quinolones analysis from our part of the province (city) clinical diagnosis typical E. coli disease or illness salmonellosis, E. coli isolated from dead poultry 361, Salmonella strain 224. Select 1-4 behalf of 10 kinds of common quinolone antibiotics, while using the disk diffusion method and microdilution susceptibility method are two methods for drug susceptibility testing. Antibiotic sensitivity tests show that from the 1990s onwards avian Escherichia coli quinolone antibiotic resistance has been a strong part of the past two decades, E. coli isolates were resistant to most quinolones have increased two times more, in addition to gatifloxacin (22.44%), but the rest of the nine kinds of quinolone antibiotic resistance rate of more than 60%. Different serotypes of E. coli resistance to quinolones there are some differences, such as O1, O2, O18 and O78 four common serotypes of avian Escherichia coli isolates, O78 serotype isolates to seven antibiotics The resistance rate of over 50%, O18 serotype isolates five kinds of antibiotics rate of over 50%, O1, O2 serotype isolates only three kinds of antibiotics was over 50%, but the difference was not significant . It is worth mentioning that the remaining 23 kinds of non-dominant serotypes also strong resistance on the six kinds of antibiotic resistance in excess of 50%. Our results suggest that, no matter what serotypes, how pathogenic E. coli, are available on a relatively equal chance of drug resistance, which makes it resistant to the public health problem is more serious and complicated. Salmonella vast majority of quinolones to maintain a high sensitivity. 1993 to 1999 Salmonella isolates to 10 kinds of quinolone antibiotics are sensitive, since 2000 we began to separate drugs such as nalidixic acid-resistant strains, and only maintain a high nalidixic acid resistance rates ( 83.74%), for enoxacin, Lomefloxaxin, ciprofloxacin, norfloxacin, ofloxacin, gatifloxacin six kinds of antibiotic resistance rates are lower than 10% of all Salmonella isolated strains to gatifloxacin in addition to a sensitive, the rest all sensitive. Resistant E. coli and Salmonella overall trend consistent over time, gradually increase the resistance, but the vast majority of Salmonella antibiotic sensitivity more than E. coli. After 2000, antimicrobial susceptibility test results showed that E. coli enrofloxacin, enoxacin, Lomefloxaxin, ciprofloxacin, norfloxacin, ofloxacin, gatifloxacin and other seven kinds of antibiotics Salmonella resistance rate is more than four times. (2) Avian Escherichia coli and Salmonella plasmid-mediated quinolone resistance gene detection and analysis of bacterial mechanisms of resistance to quinolones past generally considered the main cause of chromosome mutations (target change, active efflux and membrane porin missing), without the presence of horizontal transmission of genes can be transferred. In recent years began to appear some new quinolone resistance mechanisms, including qnr, qepA and aminoglycoside acetyltransferase gene variant aac (6 ')-ib-cr-mediated quinolone resistance, resistance genes are located in the five plasmid, making quinolone resistance in zoonotic pathogens ask spread rapidly as possible, even more serious threat of infectious diseases. According to published literature and GenBank sequences were designed and synthesized five pairs of primers were amplified five kinds of plasmid-mediated quinolone resistance genes: qnrA, qnrB, qnrS, aac (6 ')-ib-cr and qepA. The method was applied 361 avian E. coli and 224 avian Salmonella analysis. PCR results show that from 361 avian E. coli were detected aac (6 ')-ib-cr-positive strains 9, qnrB positive strains 1, qepA positive strains 3, respectively, representing 2.5% of the total number of bacteria, 0.3 % and 0.8%. 224 was not detected Salmonella plasmid-mediated quinolone resistance genes. Bonding test results show that bacteria resistant plasmid transfer around 10 kinds of quinolone antibiotic resistance has changed. Compared with the recipient strain J53aziR, combining improved child resistance 2-16 times.
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