Gill and kidney histopathology in the freshwater fish Cyprinus carpio after acute exposure to deltamethrin

The histopathological effects of deltamethrin on the gill and kidney tissues of the common carp, Cyprinus carpio were determined by light microscopy. The fish were exposed to 0.029 mg l−1 (50% of 96 h LC50) and 0.041 mg l−1 (70% of 96 h LC50) solutions of deltamethrin for short-term (96 h). The most common gill changes at all doses of deltamethrin were desquamation and necrosis. Besides, aneurism in secondary lamellae, lifting of the lamellar epithelium, oedema, epithelial hyperplasia and fusion of the secondary lamellae were reported. Lesions in the kidney tissues of fish exposed to deltamethrin were characterized by degeneration in the epithelial cells of renal tubule, pycnotic nuclei in the hematopoietic tissue, dilation of glomerular capillaries, degeneration of glomerulus, intracytoplasmatic vacuoles in epithelial cells of renal tubules with hypertrophied cells and narrowing of the tubular lumen.