Effect of triploidy on growth factors and body abnormalities in koi fish (Cyprinus carpio)

Induction of triploidy is one of the biotechnological methods in aquaculture used for genetic manipulation. The aim of this study was to evaluate the effect of triploidy on growth factors and body deformities of koi fish (Cyprinus carpio). In this experiment, induction of triploidy was performed by heat shock. For thermal shock three shock variables (38, 40 and 42°C), initiation time of shock (1, 2, 4, 6 and 8 min after fertilization) and shock duration (1, 2 and 3 min) were examined. The method of red cell nucleus measurement was used to identify the triploid fish. In order to evaluate the effect of triploid on growth factors, the initial and final weight and length of fish were measured. Growth factors, including weight gain, specific growth rate, condition factor and feed conversion ratio were then evaluated. Also, at the end of the experiment, the number of fish with body deformities was studied. The results showed no significant difference in FCR and SGR between diploid and triploid fishes. In addition, there were no significant difference in WG and CF between two groups (P>0.05). According to the results of the experiment, there were no significant difference in relation to body shape deformities between the diploid and triploid fish (P>0.05).