Abstract:
In order to understand the infection and drug resistance of Salmonella in Qinhuangdao area, 252 samples of anal swabs were collected in this experiment; bacterial isolation culture, biochemical test and PCR method were used for bacterial identification. The serotypes were determined by serum agglutination test; the susceptibility of the isolated Salmonella strains to 21 antibiotics was determined by the drug sensitive disc method; resistance genes of isolated Salmonella were detected by PCR method. The results showed that 43 strains of Salmonella were isolated, and the separation rate was 17.06%. Five serotypes were identified, with Salmonella enterica subsp. enterica serovar Enteritidis(17, 39.53%) and Salmonella enterica subsp. enterica serovar Pullorum(13, 30.23%) as the dominant serotypes. The isolated Salmonella bacteria had resistance rates of over 90% to four antibiotics, including penicillin and sulfisoxazole; the strains had resistance rates of 72.09%-88.37% to 7 antibiotics, including ciprofloxacin, compound trimethoprim and gentamicin; the strains had resistance rates of 51.16%-67.44% to 7 antibiotics such as florfenicol and polymyxin B; the strains had resistance rates of 23.26% and 27.91% to spectinomycin and ceftriaxone, respectively; the strains had a lowest resistance rate of 4.65% to ofloxacin. And the phenomenon of multi-drug resistance was serious, with the highest resistance to 20 kinds of antibiotics. 18 drug resistance genes were detected. The detection rates of blaTEM, aadA1, sul2 drug resistance genes were 97.67%, which were the highest; the detection rates of blaOXA, aadA2, aacC4 and aac(6)-Ib drug resistance genes were all 90.70%; the detection rates of catA1, sul1, tetB resistance genes were 69.77%-88.37%; the detection rates of aacC2, qnrA, qnrB, sul3, floR, aadB, tetA and qnrS resistance genes were 4.65%-44.19%; the detection results of blaPSE, blaSHV, blaCMY, tetG and cmlA were negative. The results suggested that chicken-derived salmonellosis was prevalent in Qinhuangdao area, and drug resistance phenomenon was serious.