The effects of sub-lethal doses of diazinon in zebra fish ovary tissue

Diazinon is one of the pesticides used in gardens and agricultural lands. Although aquatic ecosystems are not the purpose of these toxins, the studies show evidence of their presence and metabolites in aquatic environments, especially surface waters. The effects of sub-lethal doses of diazinon in zebra fish ovary tissue were investigated in 30-day exposure. For this purpose, 240 females with mean weight 0.2± 0.05 were subjected to 5, 10 and 20% LC50, 0, 0.8, 1.6 and 3.2 mg / L, respectively, diazinon. At the end trail, samplings were done from gonad tissue and the tissue sections were prepared. The results showed that in the control group, ovary tissue was normal and major of the oocytes were sexually at the beginning and the end of the fourth stage. In 0.8 mg / L, oocytes were in the third and the end of the third stage and a number of oocytes were observed in the second stage. In 1.6 and 3.2 mg / L, a slight increase in ovaries growth was observed, oocytes were in the second stage and hyperplasia in the granulosa layer and atrotic follicles was observed. In general, gonad tissue damage increased with increase in diazinon dose. . This indicates that oocyte growth is declining with increasing dose of diazinon. Ovarian size was significantly reduced, especially in high dose (3.2 mg / l), compared to the control group.