Histological Characteristic of the Gonads of Sardine Sardina Pilchardus (Walb, 1792) in the Coast East of Algeria (Gulf of Annaba)

International audienceTo illustrate the different kinetics of oogenesis and spawning strategies, reproduction inthe Sardine (Sardina pilchardus, Walbaum 1792) was discussed. The histological samples,realized over the 3 periods of sexual cycle: oogenesis, egg and rest, were analyzed for2217 specimens caught in the period from November 2015 to October 2016 using amicroscopic scale of oocyte development with 6 stages. The histological results allowedus to determine the size of first sexual maturity is 12 cm, acquired during the third yearof life of the sardine. Monthly monitoring of the evolution of macroscopic andmicroscopic stages of sexual maturity, allowed us to suggest that the waters of thecoastal eastern Algeria, sardines spawn from December to March. Sexual rest isobserved in the 2 sexes in May, during the summer and part of fall. Spawning and spermemission ending in April. Microscopic observations show six stages of maturity infemales and four males. Earlier maturation, oocytes come together in one lot, come intovitellogenesis and evolve synchronously to mature simultaneously. Separated from eachother by the gap, they are issued in a fractional short laying. Ongoing recruitment ofpre-vitellogenic oocytes determined new ways of oogenesis and lying, there are as manyas egg laying lots placed in vitellogenesis. This type of distribution allows multimodaloocyte laying series with lots of small eggs released during a long period of time, postspawnis difficult to identify. These results illustrate the complexity of multiple clutches