TWENTY-FIFTH ANNUAL EASTERN FISH HEALTH WORKSHOP MARCH 10-13, 2000   Cultivation Of Ichthyophthirius multifiliis On Fish Cell Lines: Possible Approaches     Natalia V. Guseva and  Dickerson  H.W.   Department of Medical Microbiology and Parasitology, College of Veterinary medicine, University of Georgia, Athens, GA, 30602     The ciliate Ichthyophthirius multifiliis causes severe losses in populations of freshwater fish around the world, including both food and ornamental species.  The development of vaccines against this obligate parasite requires routine laboratory maintenance of parasites on infected fish. These methods, however, are limited in the number of parasites that can be produced, require constant control of water quality, fish health and parasite virulence.  In vitro culture could provide more effective means for large-scale production of antigens. The presented study includes methods for sterilization of theronts and trophonts using several different antibiotics along or in combination with lysozyme. Conditions for maintenance of cell culture and parasites (temperature, CO2, serum and media concentration) are described. Development and growth of parasites on cannel catfish ovary cell line (CCO) was monitored by fixation and staining of slides at various intervals after inoculation with parasites.  The presence of I. multifiliis was confirmed by immuno-fluorescence using polyclonal rabbit and monoclonal mouse antibodies against the I. multifiliis surface immobilization antigens.  The potential use of fish cell lines for in vitro growth  I.  multifiliis will be discussed.       Return to 25th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page