Histopathological Evaluation of Zebrafish (Danio rerio) Intestinal Tissue After Imidacloprid Exposure

Abstract

The use of pesticides has been increasing day by day in order to increase productivity in agriculture. Pesticides which used in the agricultural area mix into the aquatic ecosystem through rains and groundwater etc. and it threatens the life of aquatic organisms. Nowadays, one of the most used pesticide group is neonicotinoids. Imidacloprid is the most well known in this group. In this study, it was aimed to observe the histopathological effects of imidacloprid in zebrafish intestinal tissue. Adult zebrafish individuals were administered imidacloprid in concentrations of 9.5, 19 and 38 mg/L for 5 days. When tissues are examined under light microscopy, deterioration of villi morphology, degeneration in brush border structure of epithelial cells, hyperplasia in Goblet cells and enterocytes due to inflammation, enlargement and disintegration in lamina propria were detected. In addition, hypertrophy of the smooth muscle cells and thickening in the muscularis externa layer were observed. Dysplasia was detected in the small intestine tissues in samples belonging to the highest concentration group.