The present study was performed to assess the prevalence of Salmonella in chickens in Thailand. In 1997, 22 serovars of Salmonella were isolated from 72 of 100 chicken meat samples purchased from 10 retail markets in Bangkok and 20 of 200 chicken meat samples from one slaughterhouse for export and 19 of 285 chicken feces obtained from three farms located in the east region of Thailand. The most predominant serovar was S. Enteritidis, which was isolated from 28% of the retail chicken meat, 4.5%

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... f the chicken meat from slaughterhouse, and 6.6% of chickens feces samples examined. -KEY WORDS: chicken meat, Salmonella, Salmonella Enteritidis, Thailand. samples of the breast regions of broiler chicken meat were purchased from 10 retail shops consisting of five traditional open markets and five supermarkets located in Bangkok. In the open markets, the meat was left on cutting boards at room temperature without refrigeration. In the supermarkets, it was kept in refrigerators. Two hundred samples of the breast regions of frozen broiler chicken meat for export were obtained from the slaughterhouse of one company located in the east region of Thailand. The samples collected were transferred in ice to our laboratory. Two hundred and eighty-five samples of chicken feces and 15 environmental samples such as drinking water before antibiotic agents being dissolved in, feed, floor and litter in the broiler chicken barns, and the soil on the ground at the entrance of three broiler chicken barns located in Chonburi, East region of Thailand were also collected for detection of Salmonella. The farmer introduced 1-day-old chickens and fed and supplied them with drinking water with amoxycillin added for 29 days, according to the manual of the company, and sent 46-days-old chickens to the slaughterhouse of the company. Method for isolation of Salmonella: Twenty-five grams of chicken meat, feeds, litter, or soil and the cotton swabs of the floor were put into a stomacher bag containing 225 ml of nutrient broth. The cotton was moistened with nutrient broth and swabbed on five portions of the floor (each of them was 100 cm 2 ). After stomaching, the broth was incubated at 37°C for 18 to 20 hr. After incubation, 0.1 ml of the broth was inoculated on modified semisolid Rappaport-Vassiliadis medium [5] at the edge of the plate. The plate was incubated at 42°C for 18 to 20 hr. Biochemical identification was then carried out according