Etude des paramètres microscopiques de la biologie de reproduction chez la carpe commune Cyprinus carpio communis (L.,1758) dans la retenue du barrage sidi Saad (Centre de Tunisie).

Abstract

Microscopic parameters of the reproductive biology of the common carp Cyprinus carpio communis  in Sidi Saad reservoir: The histological study of carp (Cyprinus carpio communis ) in the reservoir of the Sidi Saad aims to identify the different phases of oocyte development, describe the oogenesis kinetics and studying the spawning strategy of this species. This study was made on the ovaries of 150 female common carp caught in the reservoir. Post-ovulatory follicles and atretic oocytes were used as indicators of anterior spawning activity. Each histological phase was correlated to the macroscopic stage of maturity and to the gonado-somatic relationship in order to validate the reproductive phases for the carp. Histological analysis of ovaries shows that oogenesis can be divided in 4 phases : Vitellogenesis, partial spawning, end of lay and sexual rest. The females carp sexual cycle is composed by 6 stages: juveniles, sexual rest, early vitellogenesis, vitellogenesis, oviposition, post-laying and recovery. The presence of post-ovulatory follicles and oocytes at different stages of development indicates that the common carp is a serial spawning species. The fecundity estimation indicates that carp species carry about 102,000 eggs per kg oftheir body weight.