Vultures which used to be very common in Indian countryside some years ago are rarely seen nowadays. This is attributed to   

The correct answer is option 2.

Key Points

• Vultures in the Indian subcontinent were dying of kidney failure shortly after scavenging livestock treated with diclofenac, a painkiller that is similar to aspirin or ibuprofen.
• The Government of India banned “Diclofenac and its formulations for veterinary use” in July 2008 with a view to conserving vultures and, in July 2015, allowed use of the drug as a single-dose injection for humans only.
• According to wildlife veterinarians, the key cause of vulture deaths is food poisoning.
  • The birds were feeding on dead animals that had been administered the non-steroidal anti-inflammatory drug (NSAID) diclofenac as a painkiller.
  • When the gyps species fed on these carcasses, they faced acute renal failure and died.
• Vultures are among the top predators and are enlisted in the critically endangered category in the IUCN Red List of Threatened Species.
• The Government of India is also likely to ban the analog NSAID aceclofenac for veterinary use, given its potential to kill vultures.
  • A research note submitted by Vibhu Prakash, Principal Scientist and Deputy Director, Vulture Conservation Breeding Centre (VCBC), Panchkula, Haryana, on “Metabolism of Aceclofenac in cattle to Vulture-killing Diclofenac”, had apparently served as the basis for this move.
  • The VCBC had requested prohibition on veterinary use of aceclofenac as well. In a 2016 research study, Toby Heath Calligan (of the Royal Society for Protection of Birds) and others found that nearly all of the aceclofenac administered to cattle in the recommended dose was very rapidly metabolized into diclofenac.
• The study pointed out that at least 12 other NSAIDs, besides diclofenac, were available for veterinary use in South Asia, and aceclofenac was one of them.