Aldicarb toxicosis in a dairy herd

Aldicarb, an extremely toxic carbamate, caused sudden death of several lactating Holstein cows. Confirmation of this toxic agent as the cause of death was hindered by its rapid breakdown in biological tissue. Therefore, aldicarb was not detected in rumen contents of some of the dead cows, and brain acetylcholinesterase values were essentially normal. The analyses were conducted 2 to 4 days after death of the cows. Rapid testing of tissue samples is necessary if a carbamate insecticide is suspected.