Isolasion, identification and antimicrobial resistance patterns of Salmonella from meat products in Tehran.

The present study was carried out from 400 samples in different slaughterhouses to report the isolation along with the serotypes and antibiogram pattern of Salmonella among products in Tehran. Salmonella was isolated from samples of chicken, beef; veal, mutton, roast beef and sausage fermentive meat collected at slaughterhouses. The isolates were characterized by serotyping and antimicrobial-susceptibility testing. Eighty isolates of Salmonella enterica belonging to 19 serotypes--S. adelaide, S. agona S. abortus ovis, S. abortus bovis, S. derby, S. dublin, S. enteritidis, S. havana, S. heidelberg, S. indiana, S. infantis, S. kentucky, S. montevideo, S. newport, S. saint paul, S. senftenberg, S. typhimurium, S. thompson, S. worthington were obtained with an overall prevalence of 20%. The most strains of Salmonella enterica were isolated from roast beef. S. enterica serotype Thompson and S. enterica serotype typhimurium were isolated most frequently. All of the isolates were resistant to at least one antibiotic and 94% were resistant to at least three antibiotics. Six% were resistant to ceftriaxone, the drug of choice for treating salmonellosis in children. One isolates of S. enterica serotype infantis had resistance to 15 antibiotics and the one isolate of serotype Thompson and one isolate of Serotype havana were resistant to 14 antibiotics. Norfloxacin, cefteriaxone and cefotaxime were most effective, whereas, erythromycin, tetracycline, nalidixic acid, furazolidone and nitrofurantoin were relatively less effective. Resistant strains of Salmonella are common in meat products. These finding provide support for adoption of guidelines for the prudent use of antibiotics in food animals and for a reduction in the number of pathogens present on farms and slaughterhouses. Thus, it is imperative that salmonellosis control measures adopted for humans should give adequate importance to its control in animals particularly their products.