A histological study of ovarian development and spawning peak of Silver pomfret (Pampus argenteus, Euphrasen, 1788) in the Persian Gulf (Qeshm coastalwaters)

In this study, reproduction cycle of Silver pomfret (Pampus argenteus, Euphrasen, 1788) was examined in the coastal waters of the Persian Gulf waters (Qeshm Island). Sampling was done using gill and fixed net, in 5-10 m depth, during April 2011 to March 2012. At the end of sampling period, 474 fish were collected (292 male and 182 female). Male to female ratio was increased in month of peak spawning (P < 0.001, Chi-square) and the overall percentage of males during this period was 67%. Maturity cycle and histology classification was descriptive based on surface status, oocyte size, follicle layer, cell wall, vacuoles, nucleus and pri-nucleus. At the end of study, seven stages of ovarian development were recognized. These stages are including, virgin, resting, developing, developed, gravid, running or spawning and recovery. Also, no significant differences (Two way ANOVA, P > 0.05) were observed in the oocytes size frequency distribution between different parts of ovary (proximal, middle and distal). Females are most fecund at 24.5-26 cm (SL) and males are most fecund at 20-21.5 cm length class (SL). This species has a prolonged spawning period as extend of April to September. Two peak spawning observed for both sex. The first peak in May and the second peak in July were observed for females and the first peak in June and the second peak in July were observed for males. At the end of experiment, it was concluded that there was no difference between reproduction cycles of Silver pomfret in compare with other repetitious spawning fishes.