In November 1994 2 donkeys died acutely in a pasture at Danby, New York. At necropsy at the New York State College of Veterinary Medicine, Cornell University, no significant gross or histopathological lesions were found in either donkey. After the death of the second donkey, a toxic cause was suggested. Stomach contents submitted for toxicologic analysis from the second donkey were positive for cyanide. Together with the history and clinical signs, this result provided the basis for a diagnosis of cyanide poisoning in these donkeys.