RESUMEN
To study the effects of environmental carcinogens on the immune system of Cyprinodon variegatus, we had to miniaturize or modify standard immunological procedures due to the small size of the fish. Modifications in standard bleeding procedures allowed collection of sufficient serum for most serological procedures. Serum electrophoresis showed considerable variation between exposed and unexposed fish as did qualitative immunoelectrophoresis techniques. We successfully adapted a bacteriophage neutralization procedure for use with the C. variegatus system to measure antiviral antibodies. The presence of antibody-forming cells in spleen suspensions from fish immunized with human type O erythrocytes was demonstrated by a modified immune rosette procedure. A capillary tube procedure was developed for separation of leukocytes from erythrocytes in blood from C. variegatus.