Ovarian Histology and Histopathology of Olive Barb, Puntius sarana Exposed to Endocrine Disrupting Chemical (17-Α Methyl Testosterone) in Laboratory Condition

Abstract

17-α methyl testosterone is a major endocrine disrupting chemical (EDCs), reported harmful effect on endocrine system of aquatic animals. To study the impact of 17-αMT on olive barb (Puntius sarana) gonad, sixty fishes were collected for in vitro experiment. Hormonal treatments were carried out 90 days with three distinct hormonal dosages (T1:40 mg/kg; T2:60 mg/kg and T3:90 mg/kg) mixed with pelleted feed and no hormone in control tank (C). Each 30 days intervals, histological analysis was performed to observe alterations in the gonad due to the effect of 17α-MT. Four gamete developmental stages of female P. sarana ovary were identified through microscopic examination named immature, previtellogenic, vitellogenic and mature stage. Mild to moderate histological abnormalities has been observed in ovary for different treatments. T1 showed apparently normal histology except some alterations like empty follicle (ef), lipid droplet (ld), vitelline envelop breakdown (veb), but pronounced alterations were detected at higher concentration T2 and T3, increasing with longer exposures for instance degenerated nucleus (dn), atretic follicle (af), thickened vitelline envelop (tve), residual oocyte (roc). This preliminary study revealed more profound responses to EDCs exposure in the olive barbs which could serve as a model bio-indicator in ecotoxicological study.