Pakistan Veterinary Journal (Jun 2011)
Determinations of Reproductive Characteristics of Dusky Grouper, (Epinephelus Guaza, Linnaeus, 1758) in Antalya Bay of Eastern Mediterranean
Abstract
Describing of the various reproductive characteristics of the dusky grouper (Epinephelus guaza) is a protogynous hermaphrodite fish that fallows a monandric pathway to sexual development. The samples (n=104) were collected during a year by spear-fishing. Their 13 developmental stages of reproduction were determined. The first step was named as juvenile; the gonads of the fish were ovo-testes in which the sexual cells were not localized due to immaturities. The female characters started to begin after the juvenile form. All the fishes had different six female stages (F1 to F6) according to gonadal ripening. The first sexual maturity of the females was observed in F3 stage which they were I+ - III years old and 39.1cm (LS). Tree transitional periods (T1, T2, T3,) were seen beyond of the female period (IV -VI years old). Intersexual periods were followed by testicular phases, the fishes underwent to male sex which include tree stages (M1, M2, M3,). The first sexual maturity of the males (M2; VII-VIII years old) was started at 83.5cm (LS). However the gonado-somatic index (GSI) is most common used index for the fish. According to data; GSI were peaked in July and September in female while they were peaked in May and July in male as per cent. Furthermore, mating time was started in May according to the data of GSI and IRG, so it was means that data were parallel to both of them in the present study.