Histopathological effect of organic pollutant on male and female gonads of Goldfish (Carassius auratus)

Today, the reproductive systems of fish as a valuable model to study the effects of
the significant components of the vile endocrine disruption have been considered. This
study was inspected the testis and ovary histopathological change in Carassius auratus
(Goldfish) as a suitable alive model, exposed to two common pollutants Naphthalene,
Butachlor. The fishes received Naphthalene, Butachlor (with doses of 200 μg/l, 0.28
μg/l respectively) during 15 days including control treatment (without the chemicals).
At the end of experiment gonad tissue was examined after fixed by fixative, processed,
and embedded in paraffin as sectioned at 6μ thickness. Further stained by Hematoxylin-
Eosin general method. Histopathological lesions observed in the testes included
degenerated germ cells, proliferation and hypertrophy of Sertoli cells, development of
connective tissue, fibrosis and inhibited development of lobules, filled seminiferous
tubules with fertile sperm (at Naphtalene treatment), seminiferous tubules with no fertile
sperm in it (at Butachlor treatments). These markers weren’t observed in control group
and indicate that environmental contaminants can disrupt reproductive system of the
aquatic animals. Histopathological lesions observed in the ovary included degenerated
ooytes, cytoplasmic retraction, adhesion of the oocytes, karyoplasmic clumping and its
retraction within the oocytes and anucleated oocytes. In the ovary of control treatment,
most of oocytes were at vitellogenesis stage, but in Naphthalene treatment the majority
of the oocytes observed at previtellogenesis. In general it can be concluded that
endocrine disruption has ability to change various stages of gonadal development and
gamete development stages of males and females fish.