عنوان مقاله [English]
Caspian salmon (Salmo trutta caspius) is one of the economically valuable species in the Caspian Sea. Artificial propagation and production of larvae are of the main problems in the early culture of this species. For this target, in the propagation season in 2009, the effect of reproductive performance of female broods on opposition reproduction efficiency in Caspian salmon was studied. For this study, 3 groups of female broods (4, 5 and 6 years old) were fertilized individually by 9 male fish. The results showed that the 6-year-old females had the maximum mean of body weight before breeding (2150.0±86.6gr), after breeding (1840.0±2.92gr), total length (59±2cm), eggs weight (255.0±30.51 gr), diameter ovules (5.37±0.058mm), and fecundity rate (3060±366.15eggs).While the highest average number of ovules in each gram of body weight (16.33±0.58) and relative fecundity (2.08±0.12) belonged to the 4-year-old females. The study showed a significant difference in the mean of fertilization & survival rate until the complete absorption of yolk sack satge in the treatment group. The present study showed that the produced eggs out of fertilization of the 6-year-old females by male fish will have the maximum average rate in fertilization percentage (97.5%), survival percentage (until eyeing) (92%), hatching percentage (93%), and survival until the absorption of yolk sack stage(94.5%).