A second vulture-safe alternative to the veterinary medicine diclofenac could help large avian scavengers in South Asia.
Scientists have been working to identify vulture-safe alternatives to diclofenac, a nonsteroidal anti-inflammatory drug, since the drug was discovered in 2003 that the drug was the main cause of a catastrophic collapse of vulture populations in South Asia. . Birds ingest the drug, which is used to treat pain and inflammation in livestock and humans when retrieving carcasses from animals treated with this drug.
Four species of South Asian vultures – white-rumped (or white-backed), slender-billed, Indian, and red-headed – are now listed as Critically Endangered by the International Union for the Conservation of nature after their numbers fell in the 1990s. Estimated at 4 crore between 1991 and 1992, the population of white-rumped vultures in India fell by 99.9% between 1992 and 2007, the most recent population drop. fastest ever recorded for all bird species.
Following this discovery, in 2006 diclofenac was banned for use in livestock in India, Pakistan and Nepal, and in 2010 in Bangladesh. However, enforcement of the ban has been a persistent problem. In addition, other nonsteroidal anti-inflammatory drugs that are still legally in use have been shown to be fatal to vultures as well.
The first vulture-safe alternative to diclofenac, meloxicam, was identified in 2006.
The discovery that tolfenamic acid, a nonsteroidal anti-inflammatory drug, is also safe for vultures is the result of a systematic study of safety testing conducted by the Indian Veterinary Research Institute, with the Bombay Natural History Society and the Royal Society for the Protection of Birds. . Details of the study were published in a prepublication article in August.
Importance of tolfenamic
It is “extremely important” that tolfenamic acid has been confirmed to be safe for vultures, said Saving Asia’s Vultures from Extinction, a consortium of 24 organizations working on vulture conservation, in a report posted on its website. .
Chris Bowden, head of the Saving Asia’s Vultures from Extinction program and co-chair of the International Union for Conservation of Nature’s Vulture Specialist Group, told The third pole: âVeterinarians often complain that they like to choose between drugs for different situations. Each nonsteroidal anti-inflammatory drug has slightly different properties.
Hem Baral, a prominent Nepalese ornithologist who has studied the vulture crisis in Asia for more than two decades, said the increasing choice of vulture-safe medicines in South Asia offers “great hope” for more conservation. efficient vultures.
âPreviously, meloxicam did a great job of saving vultures by replacing diclofenac and other harmful nonsteroidal anti-inflammatory drugs,â Baral said. The third pole. But, he added, meloxicam never became the drug of choice among veterinarians in the same way as diclofenac. âIt could be a combination of supply chains, efficiency and results, combined with brand awareness and price,â he said.
Meloxicam made up only 32% of nonsteroidal anti-inflammatory drugs offered for sale in pharmacies surveyed in India in 2017. âVets knew about diclofenac and liked it, so any change is a challenge,â Bowden said. âSome say meloxicam works slower, even though it lasts longer and has fewer side effects. Tolfenamic acid has better antipyretic (antipyretic) properties than meloxicam, so it is more similar to diclofenac.
He added that the price of tolfenamic acid “should be competitive” with meloxicam and diclofenac, especially if production increases, and that it is also available in large vials – this is no longer the case for diclofenac – making it even easier to compare prices.
A key issue in the adoption of tolfenamic acid by veterinarians and farmers will be awareness and marketing. âWe rely on vets and others (including the press) to help this process,â Bowden said. âIt takes a big boost. Vets are planning webinars, but more is needed.
Prohibition of drugs
Bowden and Baral identified weaknesses in the diclofenac ban as a major problem for vulture conservation efforts. Diclofenac is still legal for use in humans. Its illicit use for veterinary purposes continues and it is also produced illegally.
Following reports of companies selling large bottles of diclofenac intended for livestock, but with labels changed to indicate they were for human use, the Indian government banned the sale of diclofenac in large vials in 2015 .
âThe vial size restriction was a major loophole, but that was fixed,â Bowden said. âThe human drug is the same thing and is available (in small vials only), but it’s hard to stop or control. Stricter enforcement and penalties with prosecutions are needed to lead by example. “
MK Ranjitsinh, a leading Indian environmentalist, said the gaps in the implementation of the ban on diclofenac for animal consumption are still being exploited. âAs diclofenac is legally used for human consumption, it is misused. If small loopholes remain in the rules, people find it easy to exploit them, âsaid Ranjitsinh. The third pole.
Another problem is the legal use of other drugs toxic to vultures for veterinary purposes. Bowden said the safety tests carried out by the Indian Veterinary Research Institute are too slow. âIt’s a serious problemâ¦ Aceclofenac [another non-steroidal anti-inflammatory drug] metabolizes to diclofenac and yet is legally used. No ban has been imposed despite requests for more than five years. This is a serious and very disappointing shortcoming.
Other deadly nonsteroidal anti-inflammatory drugs for vultures, including nimesulide and ketoprofen, “are our immediate priorities as all are legally used. [for veterinary purposes]Said Bowden. Bangladesh banned the production, sale and use of ketoprofen earlier this year, but India has yet to do so.
Recovery of vultures
The decline in vulture numbers has slowed in recent years, but the recovery process is slow and still fraught with threats, Baral said.
âSouth Asian countries that are home to vulture populations can learn from each other to improve knowledge about vulture conservation,â Baral said, adding that capacity building, knowledge exchange and cooperation cross-border will be the key to success. “As we know, vultures know no political boundaries.”
The total loss of the vultures could have immense environmental, cultural and public health implications for South Asia. When a vulture population declines, other scavengers (such as rats or dogs) can settle there. The disappearance of vultures across India in the 1990s coincided with an increase in the number of feral dogs, which in turn was pointed out as the engine of rabies. epidemic. According to calculations, the increase in the number of dogs alone resulted in the deaths of nearly 50,000 people between 1992 and 2006.
Culturally, the loss of vultures has had enormous impacts. Without vultures to consume the corpses, many Parsis had to amend the traditional âcelestial burialsâ.
The Indian Government’s Action Plan for Vulture Conservation in India 2020-2025 outlines an ambitious conservation strategy to establish new captive breeding centers and vulture âcentersâ in each state. But Bowden notes that stopping all veterinary use of diclofenac and other toxic drugs will be crucial to making the environment safe enough for the released vultures to survive.
âIndia was the first to declare a veterinary ban on diclofenac in 2006, and other countries followed,â Bowden said. “It was extremely important and probably saved these species from total extinction.” Nepal, Bowden said, has been the most successful so far and has reversed the decline in the vulture population by effectively eradicating diclofenac. âThe outings are going there and going well. All of this is much more successful than India so far. “
âWe know what to do. But we risk losing vultures because things don’t happen soon enough, âBowden said.
This article first appeared on The third pole.