Studies on reproduction of common carp (Cyprinus carpio L., 1758) in net cages

This study was conducted in 2011 and 2012 May to determine the method by which companies that produce common carp (Cyprinus carpio L., 1758) in net cages in our country can produce the carp larvaes they need without any new investment in their own company. In the study, LHRHa alone was used at high doses, in combination with dopamine antagonists (Domperidone, Metaclopramide and Haloperidol), carp pituitary extracts was injected and groups in which no administration was performed as a control group. In addition, hapa and kakabans have been tried in net cages to collect eggs. Result of the first year experiments, the highest spawning rates were found in the LHRHa + Domperidon (DOM) treated group and in control group (100%), spawning rates of the other groups were, LHRHa+Haloperidol (HALO) 83%, LHRHa+Metaclopramide (MET) 40 % and carp pituitary extract (CPE) 33,3% respectively. Differences in spawning rates and spawning index between groups were not significant (p>0,05). Result of second years experiments shows that, the highest spawning rate were found in control group (100%), spawning rates of the other groups were, 3 mg/kg carp pituitary extract (83,3%), high dose (50 µg/kg) LHRHa alone (50%). Differences in spawning rates and spawning index between control group and LHRHa group were significant (p<0.01). No significant differencies were found between carp pituitary extract group and other groups (p>0,05). Experiments results shows that common carp can reproduct in a net cage with use 0,5 mm hapas to collect fertilised eggs and hatching without any hormone applicitaions.