The Effect of Malathion Concentration and Exposure Time on Histopathological Changes in the Liver and Gill of Rainbow Trout

Figure 1

Histopathological changes in the liver tissue of rainbow trout exposed to malathion (hematoxylin–eosin staining, 400x magnification). In the control group, there was no abnormal change in the histological structure of the liver (A). At the end of Day 1, the second group (0.025 mg/L), (B) showed hepatocyte malformation (a) and melanomacrophage centers (b), the third group (0.05 mg/L) (C) showed sinusoid necrosis (c), and the fourth group (0.075 mg/L) (D) showed hyperemia (d) and degeneration (e). At the end of Day 5, the second group (0.025 mg/L) (E) showed hepatocyte malformation (f) and necrosis (g), the third group (0.05 mg/L) (F) showed hyperemia (h) and sinusoid necrosis (i), and the fourth group (0.075 mg/L) (G) showed cholestasis (j) and hepatocyte malformation (k). At the end of Day 9, the second group (0.025 mg/L) (H) showed inflammatory cell infiltration (l) and hyperemia (m), the third group (0.05 mg/L) (I) showed vacuolation (n) and necrosis (o), and the fourth group (0.075 mg/L) (J) showed hyperemia (p) and cell atrophy (q).