ESTIMATION OF THE GENETIC-VARIATION IN COMPLEMENT ACTIVITY OF COMMON CARP (CYPRINUS-CARPIO L)

The complement status of hybrid, laboratory raised carp was determined by an in vitro approach of the alternate complement activity (ACH50) and total haemolytic activity (CH50), and by measurement of serum C3 l evels. The lysis of target sheep red blood cells (RBC) in the haemolyt ic assay for CH50 activity depended, amongst others, on the haemolysin concentration in the assay. Rocket electrophoresis showed a mean seru m C3 concentration of 0.95 mg ml-1. The variation for both ACH50 and C H50 haemolytic activity was approximately 30%. The degree of genetic d etermination of the parameters was investigated by estimation of their repeatabilities, which were relatively high for CH50 (0.71) and ACH50 activity (0.72), but lower for C3 levels (0.54). Correlations between ACH50 values and C3 levels were significant, but moderate (0.54-0.58) .