Isolation, Identification, Drug Resistance Profile Investigation And Primary Study On Plasmid Characteristic Of Pathogenic Salmonella From Poult Duck In Some Cities And Provinces Of China

200 pathogenic salmonella strains were isolated and identified from poult ducks which were ill or dead because of being contracted with salmonella in 16 large-scale duck farms from defferent regions in China from 1999 to 2005. The isolates were identified by 56 kinds of salmonella diagnostic serum, 175 strains were tested for the drug sensitivity to 37 antibiotics by means of Kirby-Bauer method, 46 strains were analyzed on plasmid profile and 13 strains were studied for plasmid removal. The results show:(1)Among 200 salmonella isolates, serogroups of 47 strains were determined. There were 32 Salmonella Enteritidis isolates and 15 Salmonella Typhimurium isolates in these isolates. Serogroups in the same region were identical, but serogroups in different districts could also be identical. The result of animal experiment showed that thepathogenicity of all isolates was very high.(2) The result of antimicrobial susceptibility testing of 175 strains wasgreat surprise to us . It showed that there were 17 types antimicrobials to which the rates of 175 strains resist were more than 50 percent, especially, the rates of resistance to Penicillin G,Oxacillin Sodium,Rifampicin, Imipenem, Ampcillin, Tetracycline, Doxycycline, Erythromycin and Sinomin Compositea were more than 70%. The resistance rates of the strains to some antimicrobials were increasing in the last...