Death associated with parenteral administration of copper disodium edetate in calves.

Copper disodium edetate in recommended doses was apparently responsible for the deaths of one calf and clinical signs of toxicosis in 5 others on one farm, and 7 deaths and clinical signs of toxicosis in a number of others on another ranch. Signs of hyperexcitability, hypermetria, hindlimb weakness, head pressing, depression, and opisthotonos occurred 6 to 24 hours after injections and preceded death by 1 to 2 days. Necropsy and histologic examination revealed massive liver necrosis. High blood concentrations of liver enzymes in affected cattle that did not die indicated that they had liver damage. High blood concentration of iron in cattle that died indicated possible interaction of copper and iron.