Diclofenac is a non-steroidal anti-inflammatory drug used by farmers in India and many other countries to ease the pain in cattle. Diclofenac has become the reason for the deaths of many “Asian Vultures”. The use of diclofenac is banned in many countries including India. Scientists say it has brought some species of “Asian Vulture” to the brink of extinction with up to 99.9% decline in their population, although this drug is banned in India to treat cattle.
Populations of the White-rumped Vulture Gyps bengalensis, Indian Vulture Gyps indicus and Slender-billed Vulture Gyps tenuirostris fell rapidly during the mid-1990s in the Indian subcontinent because of the veterinary use of the drug diclofenac in cattle. This drug was found in the tissues of the dead farm animals.
According to the National Geographic, India’s Vulture populations declined in the mid-1990s. Hindu belief prohibits consumption of beef, so cows that die are disposed of outdoors. Vultures died of kidney failure after consuming cows that had been treated with the bovine drug diclofenac. The drug use in cattle was banned in India in 2006.
Dr. Vibhu Prakash, Principal Scientist, Bombay Natural History Society (BNHS) and Programme Head, National Level Vulture Conservation team says – as per an estimate, there were once 40 million birds in India and by 2007, India had lost about 99.9 percent of birds. Only a small population of vulture species remain. Vultures are long-lived and slow to breed. It starts breeding only at the age of 6-year and only 50 percent of them survive. Even if the government ban is fully implemented, it will take several years to revive the vulture population.
The death of an animal becomes the breeding ground for diseases causing microorganisms and fungus. The vultures feed off the dead animals before any bacteria or fungus could develop, preventing the spread of rabies, anthrax and many other life-threatening diseases.
The feral dog population is increasing in India as they have a lot of food left due to declining vulture population and are resistant to diclofenac. No wonder India has the highest human rabies cases registered in the world.
There is a sign of hope as the previous accelerated decline of White-rumped Vulture has slowed and may have reversed since the ban on veterinary use of diclofenac in India in 2006. The population of Indian Vulture continued to decline, but at a much slower pace as compared to mid-1990s. However, the rarest species of Slender-billed Vulture, with the population of not more than 1000 in India, has a little hope to recover from being extinct, as per the latest research paper published in Cambridge Core.
Although the Indian government has banned diclofenac use in cattle, it is just not enough to protect this magnificent raptor, as there are still other toxic substitutes which are used such as ketoprofen, aceclofenac, carprofen, which are not banned. Indian government must come up with programmes to educate the farmers and encourage them to use the alternative drugs to treat cattle such as meloxicam and subsidize this drug, which is non-toxic to vultures, as it is quite expensive.
Meloxicam is more expensive than diclofenac, but the price is coming down as more pharmaceutical companies begin to manufacture it. These programmes will not only protect vultures from being extinct, but it will significantly help maintain the ecological balance.