Abstract
Serological findings in a commercial colony of Hartley guineapigs revealed that about 70% had antibodies to Chlamydia psittaci as detected by the microimmunofluorescence method. Conjunctivitis was evident in 140% of 86 guineapigs examined. Chlamydial antigen was detected in conjunctival scrapings by a direct immuno-fluorescence test using Chlamydia-specific monoclonal antibody; however, C. psittaci was not demonstrated by other methods.