Rats exposed to a cloth impregnated with cat odor showed a decreased number of contacts with the cloth and time in contact with it and increased time sheltering from it. Exposure to the odor of rat blood produced similar, though less marked, changes and also increased the number of occasions the rat sought shelter. Exposure to the odor of disinfectant changed only the time in contact with the cloth. Exposure to cat odor also resulted in anxiogenic responses in the social interaction and elevated plus-maze tests that could be detected up to 1 h, but not 24 h, after odor exposure. Decreased exploration in the holeboard could also be detected up to 1 h, but not 24 h, after exposure to cat odor. The time in contact with the cloth, the incidence of, and time spent sheltering did not decrease over five successive exposures to the odor of a cat. The number of contacts with the control odor cloth increased over successive exposures, but contacts with the cat odor cloth did not change over successive exposures. The decreased exploration in the holeboard, as a result of prior exposure to cat odor, showed rapid habituation, as did the anxiogenic response detected in the social interaction test, whereas that detected in the plus-maze persisted for up to five odor exposures.