Ammoniated forage poisoning: Acute toxicity of newly identified dialkylimidazoles to inbred mice

The ip acute toxicity of the dialkylimidazoles 1,2-dimethylimidazole, 1,4-d imethylimidazole, 1,5-dimethylimidazole, 2,4-dimethylimidazole and 2-ethyl- 4-methylimidazole was investigated in C57B1 female mice, and compared to th e toxicity of 4-methylimidazole (4-MI). An approximate median lethal dose p rotocol was applied designed to obtain a qualitative description of the cli nical toxic effects and an estimate of the acute lethal dose with the use o f a minimal number of animals. The approximate median lethal dose of the di alkylimidazoles varied from slightly above to 3-times greater than that of 4-MI. 1,4-Dimethylimidazole and 1,5-dimethylimidazole had tremorogenic and convulsive effects qualitatively similar to those of 4-MI. Testing a mixtur e of alkylimidazoles comparable to the composition found in toxic ammoniate d forage or milk did not indicate any synergistic enhancement of the toxici ty to mice.