New drug threat to Asia's vultures
More pain-killers threaten vulture survival in South Asia
September 2012. Even as the ban on veterinary painkiller diclofenac and vulture breeding efforts of Bombay Natural History Society
) and RSPB are beginning to bear some fruit, new threats are looming on the horizon.
Another painkiller aceclofenac, used on cattle, is equally dangerous to vultures, since it gets metabolized into diclofenac. BNHS draws attention to this vital issue and also insists that to ensure long-term vulture survival, it is necessary to do safety testing of all veterinary painkillers to prevent other unsafe drugs such as ketoprofen from being used on animals.
Another vulture killer?
The new research paper emphasizes that it is important to understand the metabolic profile of veterinary painkillers. Aceclofenac, the new entrant in this category, bears close structural and pharmacological resemblance to diclofenac. It has been found that aceclofenac is a new derivative of diclofenac and gets metabolized into diclofenac.
The Gyps species of vultures in South Asia, (White-backed, Long-billed and Slender-billed, have suffered a catastrophic decline of about 99% over the past decade due to the use of diclofenac in cattle, which causes vulture deaths when the dead bodies of such cattle are consumed by them. Efforts of BNHS and RSPB led to a ban on veterinary diclofenac subsequently. Over the years, BNHS and RSPB have been successfully running Vulture Conservation Breeding Centres in three northern states of India, with help from the forest departments. Efforts are also on to measure the incidence of diclofenac after the ban and sustained advocacy and to find vulture safe zones across the country. Going forward, the crucial aspect would be total annihilation of all unsafe veterinary drugs from the system, so that the vulture programme can reach its logical culmination of rehabilitating the Gyps species back in the wild.
Commenting on the issue, Mr Sharma said, "A study demonstrating in vivo conversion of aceclofenac into diclofenac in cattle will be important. Once proven this will establish the exposure of vultures to diclofenac. The aceclofenac issue also points to the need for a comprehensive environmental evaluation of veterinary drugs before granting licenses. All other veterinary drugs, which we do not know much about, must be subjected to safety testing."
The paper demonstrates that aceclofenac should not even be safety tested on vultures as its threat to vultures is already clear. Safety testing should focus on other molecules which are still in the grey area. Other drugs such as ketoprofen are also unsafe for vultures.
Referring to the recently held Symposium in Delhi to develop a regional response for saving South Asia's vultures, BNHS director, Dr Asad Rahmani said, "In order to create a safe natural environment for vultures in South Asia, banning the unsafe drugs and safety testing of other potentially toxic drugs should be a priority."
The four governments of South Asian countries had already agreed in the Delhi Symposium that it is important to create and maintain a non-toxic environment for vultures, by identifying and preventing the veterinary use of other unsafe veterinary drugs with similar toxicity as diclofenac.
A recent research paper published in a peer-reviewed journal called "Journal of Raptor Research" (volume 46-3, 2012) highlights this threat . The new research paper is titled "Aceclofenac as a Potential Threat to Critically Endangered Vultures in India: A Review" by Pradeep Sharma from Rajasthan University of Veterinary and Animal Science, Bikaner.