标题:Histomorphological and Biochemical (Serum 17β-estradiol) Characterization of the Reproductive Cycle of Female Common Carp ( Cyprinus carpio ) in Northeast ltaly
摘要:To clarify the spawning seasonal dynamics of common carp (Cyprinus carpio) in northeast Italy, female fish were collected monthly from July 2002 to June 2003. The gonadosomatic index (GSI), histomorphology, 17β-estradiol serum concentration, and relative fecundity were compared. Between March-April and May-June, statistically significant differences were found in GSI, 17β-estradiol, and relative fecundity. Intermediate multispawner stages were found by histological analysis of specimens caught in July-August 2002 and May-June 2003. Final maturation stage was found mostly in March-April. Development trends were well correlated with water temperature. Histomorphological analysis revealed that oocytes at the exogenous vitellogenesis stage were retained throughout the winter and final maturation was reached during a short period (March-April). The beginning of the spawning season was fixed between April and May, and the end of spawning occurred during July and August.