Salmonella contamination of raw meat from domestic chickens in Tama, Tokyo between 1992 and 1999, investigated. Salmonella was detected in 197 (25.2%) of 783 samples, raning from 9.4% to 40.8% per year. On serological typing test, 202 strains isolated were classified into 20 serovars including a strain of untypable O7 and O8. The most predominant serovar was Salmonella serovar Infantis (S. Infantis) (45.0%), following S. Hadar (6.9%), S. Typhimurium (4.5%), S. Schwarzengrund and S. Vichow (2.0%). Especially, the increases in S. Infantis in the past 3 years is notable, accounting for 77 strains (84.6%).
On drug-resistance test using 9 drugs (CP, TC, SM, KM, ABPC, ST, NA, FOM and NFLX), 90% of strains tested were resistant to some of the drugs. S. Infantis isolated was resistant to all, and the main resistance patterns were TC/SM/KM/ST (28 strains), TC/SM/KM (26 strains), and TC/SM (20 strains). Almost all strains of S. Hadar and S. Typhimurium also were resistant to 2 to 5 drugs.
