EN
An increase in number of Salmonella serovar Mbandaka in animals was observed in Poland in the years 1995 - 1997. Eighty seven Salmonella serovar Mbandaka strains isolated from animal feed, poultry and food products were examined biochemically. Two biotypes were found, but 96.6% oTTfitf strains belonged to inositol-positive biotype I. All strains tested were lysed by phage O-l. Resistance to at least one antimicrobial agent was found in 28.7% of examined Salmonella serovar Mbandaka strains and 88% of them showed multi-resistance. Resistance to tetracycline and streptomycin was found to be the most common. Four out of 87 / strains showed resistance to nalidixic acid. One of them proved to be enrofloxacin-resistant. Most of the Salmonella serovar Mbandaka strains (95.4%) were plasmid free. The occurrence of 4 plasmid profiles was observed in 4 different strains. Two strains carried large single plasmids of about 38.7 MDa and 70.8 MDa. Two others harboured, respectively, 2 and 3 small plasmids of less than 2.0 MDa molecular weight.