Studies On Sub-chronic And Chronic Toxicity Of Melamine On Kitten And Rat

To verify and evaluate the sub-chronic toxicity of melamine (MA), a1000mg MA per kilo feed single probe dose test was subjected to a Chinese Li Hua weaning kitten; and further a500mg,1000mg and2000mg MA per kilo feed test was conducted on6-week-old female Wistar rats for180d too, to make more detailed assessment of chronic toxicity of MA. Biochemical index, as ALT, AST, GGT, CRE and UA were all abnormally increased as time extended, implies malfunction of kidney and liver of the animals. Histological abnormal or damage were found in kidney, liver and bladder. Renal damage was severe in kitten and the highest dose group of rat, and the latter were observed crystal-like substances in kidney and growth and food intake were hindered as well. No abnormality was found in blood routine test and no pathological change observed in spleen and bone marrow. In conclusion, MA has obvious sub-chronic and chronic toxicity effect in the experiment doses, kidney, liver and bladder are major target organs, the estimated MNEL of MA should be lower than35.7±15.4mg/kg-bw-d.