Description: The emergence of bacterial strains resistant to antibacterial drugs has become one of the most significant problems in human and veterinary medicine. To examine the extent of the problem in bacteria of veterinary importance in Israel, the results of the in vitro susceptibility tests of Salmonella enterica serogroup B, Escherichia coli, Proteus spp., Pseudomonas aeruginosa, Pasteurella multocida and Mannheimia haemolytica, isolated from animals between 1990 and 2009, were assessed and statistically analyzed. The results showed that out of 52 bacterium/drug combinations tested, no statistically significant changes or increase in susceptibility were observed in 59.6 percentage and 26.9 percentage of the combinations, respectively. A decrease in susceptibility was found in 13.5 percentage of the combinations, most significantly for the fluoroquinolones