DIVERGENT SELECTION FOR ANTIBODY-PRODUCTION IN COMMON CARP (CYPRINUS-CARPIO L) USING GYNOGENESIS

A base population (n = 101) of carp, consisting of a single hybrid cro ss, was immunized with the hapten-carrier complex DNP-KLH, to perform a divergent selection for antibody response. Measurement of the DNP-sp ecific antibody response at 12 and 21 days postimmunization, allowed t he classification of a low number of individual carp as early/high (10 %) or late/low (13%) responders. Three individuals defined as early/hi gh and three defined as late/low responding, were gynogenetically repr oduced to obtain corresponding homozygous progenies within one generat ion only. Upon immunization with DNP-KLH, the antibody response was fo und to be significantly higher in the early/high responder homozygous offspring. Although the homozygosity of the offspring apparently cause d a (s)lower antibody response (compared with the base population), th e differences between the high and low responder offspring do indicate a genetic influence on the antibody response. The realized heritabili ty (h(2)) for antibody production was estimated at 0.37 +/- 0.36. The present study provides the basis for a divergent selection of homozygo us inbred carp lines with a genetically controlled difference In antib ody response. These inbred lines will allow us to investigate relation ship(s) between immune responsiveness and resistance to infectious dis eases in fish.