Vulture Restaurants and veterinary drugs
A veterinary pain killer known as diclofenac (see below) has been shown to be very toxic to old world vultures such as our Cape Griffons and African White-backed vultures. Veterinary use of this same drug has resulted in declines in vulture numbers by more than 98% across South Asia. Although diclofenac is not used in cattle or horses in South Africa, preliminary laboratory tests tend to suggest that other veterinary pain-killers may be equally as toxic.
While we would like to strongly suggest that any meat/carcasses placed out at your restaurant is free of all medication for at least one week before the animal died, the following are strongly recommended to prevent the accidental poisoning of our vulture species:
- Avoid placing out carcasses previously treated with flunixin (Finadyne ®, Cronyxin ® and Pyroflam ®) or ketoprofen (Ketofen ®) or phenylbutazone (Tomanol ®, Phenylarthrite ®, Equipalazone ® or Fenylbutazone ®).
- Avoid placing out any carcasses that were euthanased with pentobarbitone (Euthanase ® and Euthapent ®)
- Avoid any game carcass that died following drug immobilizing e.g. M99 ®, Zoletil ®, Dormicum ®.
- Avoid carcasses that were recently treated for ticks or for tick-bite fever (Redwater) e.g. Berenil®.
However, if it is not possible to avoid the above carcasses, it is recommended that the liver and kidneys are destroyed prior to placing out the carcass; as these organs contain highest concentrations of these drugs. While this will reduce the likelihood of toxicity, it should be pointed out euthanasia agents and the capture drugs might still be toxic in the meat.
Thank you for your willingness to make the practice of vulture restaurants safer.
Diclofenac
Diclofenac is a veterinary drug that has decimated Asian vulture populations. Diclofenac is marketed under many different brand names. As a human medicine it is traded as Voltaren. This drug could be catastrophic for vultures in Africa . There are safe alternative drugs available, e.g. Meloxicam (Swarup et al 2007) so there is actually no need for Diclofenac at all.
In South Asia, populations of the endemic Oriental white-backed (Gyps bengalensis), long-billed (Gyps indicus) and slender-billed vultures (Gyps tenuirostris) plummeted by more than 99% since the early 1990s. These three species, which together used to number tens of millions, are now at high risk of global extinction and are listed as Critically Endangered (IUCN 2004). Veterinary use of Diclofenac, a Non-Steroidal Anti-Inflammatory Drug (NSAID), is the cause of these declines (Green et al. 2004; Oaks et al. 2004) in the Indian sub-continent.
Vultures are exposed to Diclofenac when they consume carcasses of livestock that have been treated with the drug and nonetheless died within a few days of treatment. Gyps vultures are extremely sensitive to Diclofenac, which even in very low doses causes gout and death. Veterinary use of Diclofenac in Africa could quickly put the Cape vulture Gyps coprotheres (VU) in even greater danger of extinction, and further threaten Ruppell’s griffon vulture Gyps rueppellii (NT), white-backed vulture Gyps africanus (NT) and griffon vulture Gyps fulvus (LC). Gyps vultures are very wide ranging. For example in just over one year a Cape Vulture satellite-tagged in Namibia covered at least 64,000 kilometres through six countries: Namibia, Angola, Botswana, Zambia, Zimbabwe and South Africa. Exposure to Diclofenac in a single carcass in any one of their range states could prove fatal, and threaten the more common species as well as the already rare ones.
Surveys of veterinarians and zoos document the outcomes of the treatment of over 870 scavenging birds from 79 species. NSAID toxicity was reported for raptors, storks, cranes and owls, suggesting that the potential adverse conservation impact of NSAIDs may extend beyond Gyps vultures and could be significant for all vultures. In Africa this would include the threatened Egyptian vulture Neophron percnopterus (EN), White-headed vulture Trigonoceps occipitalis (VU) and Lappet-faced vulture Torgos tracheliotus (VU).
In contrast, there were no reported mortalities for the NSAID Meloxicam, which was administered to over 700 birds from 60 species. The relative safety of Meloxicam supports other studies indicating that it is a suitable substitute NSAID for Diclofenac.
All key references are downloadable from http://www.vulturedeclines.org/