Determination of maturation and spawning season of Otolithes ruber (Croaker Fish) in Khuzestan coastal water, Iran

Document Type : Research Paper

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Abstract

In this study, the stage of gonadal development, type and season of spawning of Otolithes ruber in the North West of Persian Gulf were identified. O.ruber maturation and spawning were studied by macroscopic, microscopic, and histologic observation of gonads which obtained from October 1996 to September 1997 in Khouzestan coasts. In the histologic sections of gonad tissue, stages I to VII of gonadal development were distinguished. Post Spawning follicules were observed only in stages VI and VII (in April and May). Atretic ovums were also clearly observed in these stages. Frequency of Ovum diameter distribution in stages II to V is a unimodal which proves that annual maturation of ovums and spawning of this species are simultaneous. The highest level of GSI was observed in March and also higher stages 01' gonadal maturation were observed in March and April. Fast drop in GSI in May and within occurrence of both spawning and spent individuals in only two months of the year shows the relati.....

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