Histopathological effects of Endothall on ovaries tissue of zebraf

Keywords: Endothall, histology, histopathology, ovaries, zebrafish Endothall is a relatively water-soluble contact herbicide, primarily used to control of submerged weeds. Although many studies have been done with various endothall formulations that address both toxicity and environmental fate and persistence, it is still a herbicide under investigation for its effect. At the same time, herbicides are mixing with groundwater and affect the ecosystem in the water. There are some consequences of mixing these substances into the aquatic ecosystem. In this study, after one week of adaptation period female zebra fish were divided into 4 groups as one control and 3 experimental groups (0.1 mg/L, 0.5 mg/L and 1 mg/L). Ovaries were dissected after 5 day of the exposure. Tissues were fixed with bouin solution and dehydration were carried out in ascending series of ethanol. Tissues were cleared in xylene, embedded in paraffin wax and cut into 5 μm sections with a microtome. The sections were stained with Hematoxylin-Eosin, Masson-Trichrome and PAS. Results were evaluated with light microscope. Endothall (0.1 mg/L, 0,5 mg/L and 1 mg/L) exposed group; common condensation in chromatin material, separations between zona radiata and follicular epithelial, vacuolization and irregularities on nucleolus observed. In 0.1 mg/L Endothall group as double nuclei were observed, unlike other doses. Parallel to dose increase, severe damage in connective tissue was observed. As a result, the histopathological deterioration observed in the ovarian structure showed that Endothall had a negative effect on reproduction.