Pathological Studies On Copper Poisoning Experimentally In Carp

The systemic pathologies on acute, subacute copper poisoning in carp were first studied, which discussed the security of copper used in aquiculture. The 24h LC50,48h LC50, 96h LC50 of acute poisoning were 1.67mg/L, 1.25mg/L, 0.77mg/L, respectively. Safe concentration was 0.077 mg/L. The mucus of body surface and gill increased in poisoned fish. There were some blue floccules in gills. Nervous sign, difficult breath and death were occurred in poisoned fish. The lesions of acute cases showed gill lamella hyperplasia like sticks; granular degeneration, vacuolar degeneration, necrosis in liver cells and renal tubular epithelial cells; pancreas degeneration, necrosis; intestinal mucous membrane epithelial cells degeneration. Mitochondria of liver cells swollen with disintegration and lysis of cristaes. Endoplasmic reticulum of neurocyte dilated with Shedding of ribosome particles. The subacute poisoning test was conducted for 5 weeks, with concentrations of 0.03mg/L, 0.05mg/L, 0.10mg/L, 0.18mg/L, 0.32mg/L.The morbidity and mortality were respectively 5%, 17.5%, 25%, 32.5%, 52.5% and 0, 2.5%, 5%, 10%, 15%. The clinic symptom of poisoned fish resembled acute poisoned fish', but there was no blue floccule in gills. The colour of poisoned fish darkled, While the growth of poisoned fish was inhibited obviously. The lesions of subacute cases showed hyperplasia, degeneration, necrosis in the gill lamella epithelium; vacuolar degeneration in cardiac muscle fibre; vacuolar degeneration, lytic necrosis in the liver cells and renal tubular epithelial cells; coagulated necrosis or lytic necrosis in the glandular cells; intestinal epithelium cells necrosis; edema, hyperemia, hemorrhage in brain and degeneration, necrosis in neurocyte. The karyotheca dilated, mitochondria dissolved into vacuole, quantity of lysosome increased and volume of lysosome enlarged in liver cells. Microvilli of bile canaliculi sloughed and collapsed. Mitochondria dissolved into vacuole in intestinal mucous membrane epithelial cells. The karyotheca dilated and mitochondria swollen with disintegration and lysis of cristae in renal tubular epithelial cells. Haematologically, the red cell count and hemoglobin decreased, serum SOD, CP, AKPactivity dropped; serum GPT activity arised. In microkernel experiment, the differences between control group and subacute poisoned groups were significant, which showed copper had hereditary toxicity to carp. Using atomic spectrophotometer examined copper contents of liver, kidney, muscle and gill in subacute poisoned fish. The sequence of accumulation was liver, kidney ,gill, muscle. Result of x-ray microanalysis showed that content of copper of microvillis was the most, while copper of cytosol was the least in liver cell and renal cell.