Ethylene Glycol Poisoning in Two Griffon Vultures (Gyps fulvus) in Italy

Abstract

Poisoning is a major cause of anthropogenic death and population decline in vultures, posing a serious conservation problem for several species. This report describes mortality consequent to ethylene glycol (EG) poisoning in two Griffon Vultures Gyps fulvus in Italy. One was observed alive showing abnormal hypoactive behavior 3 d before corpse retrieval. At necropsy, the main pathologic findings of severe tubulonephrosis with accumulation of oxalate crystals and hepatocellular necrosis in both animals were strongly suggestive of EG poisoning, confirmed by chemical analysis of the liver and gastric contents. Estimated postmortem intervals dated both deaths to the same 72 h timeframe, suggesting a common source of exposure and indicating that the bird seen alive died soon afterwards. An alcoholic compound, EG is widely used as an antifreeze or industrial solvent and frequently detected in poisoning casualties. It has a sweet taste, and animals may consume it unintentionally, in poisoned baits, or by scavenging poisoned carcasses. Although the source of the toxin for these vultures remains unknown, this report underlines the importance of vultures' post-mortem surveillance for the early detection of environmental contaminants and conservation threats. According to the available literature, EG poisoning has not previously been reported in any vultures in Europe nor in Griffon Vultures worldwide.