Incidence of resistance to tetracycline,chloramphenicol and ampicillin amongSalmonella species isolated in the Netherlands in 1969, 1970 and 1971

In 1969, 1970 and 1971 respectively, 11761, 13844 and 20053Salmonella strains were screened for resistance to ampicillin, chloramphenicol and tetracycline. It was found that in these years respectively 23.4%, 19.3% and 15.1% of the isolated strains were resistant to one or more of these antibiotics. Most strains appeared to be only tetracycline-resistant. Resistance to chloramphenicol remained low (0.56% and less). During 1971 64 kanamycin-resistant strains (0.32%) were isolated. Resistance was largely confined toS. typhimurium andS. panama.