antibiotic resistance of bacteria isolated from mice’s intestine in lahijan

background: disease transmission by rats and mice is a worldwide problem of big cities, which is important economically and also a significant health problem. this study was carried out to identify bacterial species find out antibiotic resistance of isolated bacteria in local rat's population in lahijan - iran. methods: cluster random sampling design was used to study  a total sample of 100 rodent species, from 13 different regions within the lahijan city. rats were killed by using  ether inhalation and sterile swabs were used to collect samples from cecum.   the collected swabs were cultured for bacterial growth on different media.  cold enrichment phosphate buffer was used for isolation of yersinia enterocolitica . antibiotic sensitivity was determined by using kirby-bauer's method. spss software was used for data analysis. results: a total of 100 rats were entrapped. 94 of them were of rattus norvegicus and the other 6 of rattus rattus types. the results showed that 70% of the rodents were carriers of proteus species, 34% klebsiella, 20% entero pathogenic ecoli, 4% salmonella typhimurium, 45% enterobacter cloacae, 64% citrobacter spp, 75% non-pathogenic e coli, 19% serratia marscesins, 41% hafnia alveoi, 57% pseudomonas aeroginossa, 10% yersinia enterocolitica, 31% aureus, 38% coagulase negative staphylococcus, 13% streptococcus faecalis and 40% bacillus cereus. the most sensitive antibiotics included ciprofloxacin, nalidixic acid  and cotrimoxazole. conclusion: we concluded that mice and rats are potentially able to transmit  diseases to human. further studies about health and economic effects of rats in large cities are recommended.