Investigation of reproductive performance and fecundity in two group of rainbow trout brood stock

The study aims to evaluate the reproductive factors as well as fecundity of two broodstock groups (Iranian and French generation) at the research center of genetic and breeding of cold-water fishes, Yasouj, Iran. Number of 10 broods from French generation and 15 broods from Iranian one were randomly selected, tagged and stripped to evaluate fecundity and future parameters. Total egg weight and egg diameter were computed using a digital balance and a caliper. After fertilization, the percentage of fertilized, eyed, hatched eggs and larval survival were assessed . Average fecundity and egg diameter in the French generation were 4080±306.47 and 4.93±0.089 respectively. Mentioned parameter in the Iranian were submitted to be 4247±276 and 5.17±0.1. Moreover, percentage of fertilized egg (98.8, 88.33), percentage of eyed eggs (94.5,71) and hatching rate (82.5,70) were submitted in the Ferench and Iranian groups respectively. A possitive relationship was observed between fecundity and fish weight in French (r= 0.36) and Iranian ( r= 0.52) groups. A linear relationship between fecundity and length fish was observed in rainbow trout French (r = 0.30) and Iranian (r = 0.36). In conclusion, it seems that fish fecundity is more affected by fish weight, not fish length.