Figure 1: Histopathological photomicrographs of gills of Heteropneustes fossilis under control conditions (Co), glyphosate-treated laboratory conditions (GL), and glyphosate-treated field conditions (GF). (A) Normal structure of primary gill lamellae (PGL) and secondary (SGL) lamella under light microscopy (Co, 400×). (B) Hypertrophy (arrow), fusion (white arrow) of SGL and distortion of chloride (oval) and pillar cells (broken arrow) under light microscopy (GL, 400×). (C) Partial fusion of SGL (white arrow) and hypertrophy (arrow) under light microscopy (GF, 400×). (D) SEM showing normal arrangement of gill rackers (GR) with primary gill lamellae (PGL) and stratified epithelial cells (SEC) on the PGL (Co, 200×). (E) Gill epithelium showing loss of Microridge (MR) in SEC (arrow) under SEM (GL, 8000×). (F) Almost normal appearance of MR in SEC and excess mucin (M) droplets under SEM (GF, 5000×). (G) Gill epithelial cell under TEM showing normal chloride cells (CC), pavement cells (PC) with prominent mitochondria (M) with apical pore (square) (Co, 3200×).(H) Degenerative chloride cells (arrow), severe distortion in mitochondria (bold arrow), severe cytoplasmic vacuolation (broken arrow) with dilated endoplasmic reticulum underTEM (GL, 2500×). (I) Vacuolation (broken arrow) and dilated mitochondria (bold arrow) under TEM (GF, 8000×). SEM = scanning electron microscopy; TEM = transmission electron microscopy.