Veterinary Use Of Diclofenac Research Articles

Spatial patterns in the diet of Gyps vultures in India and their implications for conservation

Dietary analyses are particularly useful for developing conservation programmes for species threatened by resource depletion, poisoning and environmental pollution. Gyps vultures in South Asia represent one such case, having undergone a population collapse caused by feeding on carcasses of cattle treated with the non-steroidal anti-inflammatory drug diclofenac. Following a ban on the veterinary use of diclofenac, populations of vultures remain low and mostly concentrated near protected areas. Understanding the role of protected areas in the recovery of these critically endangered species requires analyses of spatial variation in their diet. We used faecal metabarcoding to investigate the spatial variation in the diet of Gyps vultures across four landscapes from sites located inside and outside protected areas. We collected faecal 642 samples, of which 419 yielded adequate molecular data to identify the vulture species and 30 molecular operational taxonomic units corresponding to at least 28 diet species. The diet was dominated by large ungulates and varied across landscapes, protection status and vulture species, with the observed variation largely explained by differential intake of wild and domestic species. Domestic livestock was present in >95 % of the samples from Central, West and North India, but 77 % of the samples had only wild species in South India. This variation was explained by livestock density within 100 km radius of the sampling site. Our results imply that protected areas may not offer a respite from possibility of diclofenac-poisoning across most parts of the country and efforts should continue unabated to remove nephrotoxic drugs from veterinary use.

Recent trends in populations of Critically Endangered Gyps vultures in India

Summary This paper reports results from the eighth of a series of road transect surveys of Gyps vultures conducted across northern, central, western, and north-eastern India since the early 1990s. Populations of the White-rumped Vulture Gyps bengalensis, Indian Vulture G. indicus, and Slender-billed Vulture G. tenuirostris declined rapidly, beginning in the mid-1990s. The principal cause of the declines was poisoning due to widespread veterinary use of the non-steroidal anti-inflammatory drug (NSAID) diclofenac on cattle. The results of the current survey suggest that, while populations of all three species of vulture remain at a low level with no signs of recovery, they appear to have been approximately stable since veterinary use of diclofenac was banned in the mid-2000s. Population trends in India, where the illegal use of diclofenac and legal use of other toxic NSAIDs continues, are compared with more positive trends in Nepal, where the veterinary use of toxic NSAIDs appears to have been reduced to a low level.

Poisoned baits pose a threat to vultures in Nepal

Poisoning is the greatest threat to vultures globally. Asia’s vultures were driven to near extinction through poisoning by the veterinary non-steroidal anti-inflammatory drug (NSAID) diclofenac. Since the ban on the veterinary use of diclofenac in Nepal in 2006, there has been a partial recovery of vulture populations in the country. However, other threats are emerging, including other vulture-toxic NSAIDs, as well as other forms of unintentional poisoning. The use of poison baits, whereby animal carcasses are laced with poison to target carnivores, often results in the collateral deaths of vultures. Here, we summarize the data on the number of such poisoning incidents, and the number of vultures killed, between 2011 and 2023. A total of 224 vultures of seven species were found dead at 22 poisoning incidents across the country. Himalayan griffons accounted for over half of the fatalities (n = 108), along with 93 White-rumped vultures and small numbers of four other species. We recommend that conservationists raise the awareness of this issue with local stakeholders, and try to devise mitigation measures to reduce the threat of poisoning to vulture population.

Metabolism of aceclofenac to diclofenac in the domestic water buffalo Bubalus bubalis confirms it as a threat to Critically Endangered Gyps vultures in South Asia

Vulture declines in South Asia were caused by accidental poisoning by the veterinary non-steroidal anti-inflammatory drug (NSAID) diclofenac. Although veterinary use of diclofenac has been banned, other vulture-toxic NSAIDs are legally available, including aceclofenac, which has been shown to metabolise into diclofenac in domestic cattle. We gave nine domestic water buffalo the recommended dose of aceclofenac (2 mg kg−1 body weight), collected blood at intervals up to 48 h, and carried out a pharmacokinetic analysis of aceclofenac and its metabolite diclofenac in plasma. Aceclofenac was rapidly converted to diclofenac, and was barely detectable in plasma at any sampling time. Diclofenac was present within 20 min, and peaked 4–8 h after dosing. Aceclofenac is a prodrug of diclofenac, and behaves similarly in domestic water buffalo as it did in domestic cattle, posing the same risk to vultures. We recommend an immediate ban on the veterinary use of aceclofenac across vulture-range countries.

Partial recovery of Critically EndangeredGypsvulture populations in Nepal

SummaryPopulations of Critically Endangered White-rumpedGyps bengalensisand Slender-billedG. tenuirostrisVultures in Nepal declined rapidly during the 2000s, almost certainly because of the effects of the use in livestock of the non-steroidal anti-inflammatory drug diclofenac, which is nephrotoxic toGypsvultures. In 2006, veterinary use of diclofenac was banned in Nepal and this was followed by the gradual implementation, over most of the geographical range of the two vulture species in Nepal, of a Vulture Safe Zone (VSZ) programme to advocate vulture conservation, raise awareness about diclofenac, provide vultures with NSAID-free food and encourage the veterinary use in livestock of a vulture-safe alternative NSAID (meloxicam). We report the results of long-term monitoring of vulture populations in Nepal before and after this programme was implemented, by means of road transects. Piecewise regression analysis of the count data indicated that a rapid decline of the White-rumped Vulture population from 2002 up to about 2013 gave way to a partial recovery between about 2013 and 2018. More limited data for the Slender-billed Vulture indicated that a rapid decline also gave way to partial recovery from about 2012 onwards. The rates at which populations were increasing in the 2010s exceeded the upper end of the range of increase rates expected in a closed population under optimal conditions. The possibility that immigration from India is contributing to the changes cannot be excluded. We present evidence from open and undercover pharmacy surveys that the VSZ programme had apparently become effective in reducing the availability of diclofenac in a large part of the range of these species in Nepal by about 2011. Hence, community-based advocacy and awareness-raising actions, and possibly also provisioning of safe food, may have made an important contribution to vulture conservation by augmenting the effects of changes in the regulation of toxic veterinary drugs.

Recent changes in populations of Critically EndangeredGypsvultures in India

SummaryPopulations of the White-rumped VultureGyps bengalensis, Indian VultureG. indicusand Slender-billed VultureG. tenuirostrisdeclined rapidly during the mid-1990s all over their ranges in the Indian subcontinent because of poisoning due to veterinary use of the non-steroidal anti-inflammatory drug diclofenac. This paper reports results from the latest in a series of road transect surveys conducted across northern, central, western and north-eastern India since the early 1990s. Results from the seven comparable surveys now available were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level. The previously rapid decline of White-rumped Vulture has slowed and may have reversed since the ban on veterinary use of diclofenac in India in 2006. A few thousand of this species, possibly up to the low tens of thousands, remained in India in 2015. The population of Indian Vulture continued to decline, though probably at a much slower rate than in the 1990s. This remains the most numerous of the three species in India with about 12,000 individuals in 2015 and a confidence interval ranging from a few thousands to a few tens of thousands. The trend in the rarest species, Slender-billed Vulture, which probably numbers not much more than 1,000 individuals in India, cannot be determined reliably.

Recent changes in populations of Critically Endangered Gyps vultures in India

Populations of the White-rumped Vulture Gyps bengalensis, Indian Vulture G. indicus and Slender-billed Vulture G. tenuirostris declined rapidly during the mid-1990s all over their ranges in the Indian subcontinent because of poisoning due to veterinary use of the non-steroidal anti-inflammatory drug diclofenac. This paper reports results from the latest in a series of road transect surveys conducted across northern, central, western and north-eastern India since the early 1990s. Results from the seven comparable surveys now available were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level. The previously rapid decline of White-rumped Vulture has slowed and may have reversed since the ban on veterinary use of diclofenac in India in 2006. A few thousand of this species, possibly up to the low tens of thousands, remained in India in 2015. The population of Indian Vulture continued to decline, though probably at a much slower rate than in the 1990s. This remains the most numerous of the three species in India with about 12,000 individuals in 2015 and a confidence interval ranging from a few thousands to a few tens of thousands. The trend in the rarest species, Slender-billed Vulture, which probably numbers not much more than 1,000 individuals in India, cannot be determined reliably.

Potential threat to Eurasian griffon vultures in Spain from veterinary use of the drug diclofenac

Summary Spain holds > 95% of the European breeding population of the Eurasian griffon vulture Gyps fulvus. Vultures provide important ecosystem services in carcass removal and influence emissions of greenhouse gases. Despite the known toxicity of the non‐steroidal anti‐inflammatory drug diclofenac to this species and other Gyps vultures, in March 2013 the Agencia Española de Medicamentos y Productos Sanitarios (AEMPS) approved the use of two medicines containing diclofenac for veterinary use in horses, pigs and cattle in Spain. To assess the potential impact of medicated ungulate carcasses on Eurasian griffon vulture populations in Spain, we first used information on the metabolism and elimination of diclofenac from medicated cattle and pigs to calculate residue levels in relation to time elapsed between dosing and death. Secondly, probabilities of the death of a vulture per meal were calculated based upon experimental studies of diclofenac toxicity. Finally, annual numbers of vulture deaths expected to be caused by diclofenac were obtained by multiplying the death rates per meal by the estimated numbers of vulture meals taken from expected numbers of medicated carcasses suggested by AEMPS. Assuming that vultures feed on carcasses that were treated with diclofenac 8 h before the animal's death, the annual number of vulture deaths caused by diclofenac was estimated at 715–6389, depending upon the estimate of numbers of medicated carcasses assumed and the version of the dose–response model used. Using a density‐independent simulation model of a vulture population, the expected rate of decline of the Spanish population of Eurasian griffon vultures caused by these deaths is 0·9–7·7% per year. A density‐dependent simulation model also indicated substantial population‐level effects. Formal estimates of precision and sensitivity analyses of effects of unmeasured variables highlight the uncertainty of estimates using currently available data. Synthesis and applications. Due to the possibility of causing an important impact on vulture populations, our findings justify a precautionary ban on the veterinary use of diclofenac in Spain and encourage the use of meloxicam, a vulture‐safe alternative drug. A programme of monitoring of non‐steroidal anti‐inflammatory drug contamination of ungulate carcasses available to vultures and of moribund and dead obligate and facultative avian scavengers would be needed to be confident that a damaging level of contamination is not present.

Population trends in Himalayan Griffon in Upper Mustang, Nepal, before and after the ban on diclofenac

SummaryThe Upper Mustang region of Nepal holds important breeding populations of Himalayan Griffon Gyps himalayensis. Despite this species being considered ‘Least Concern’ on the IUCN Red List, the population in Upper Mustang had declined substantially in the early to mid-2000s. During that period, the non-steroidal anti-inflammatory drug diclofenac was commonly used to treat illness and injury in domesticated ungulates throughout Nepal. The timing and magnitude of declines in Himalayan Griffon in Upper Mustang resemble the declines in resident populations of the ‘Critically Endangered’ White-rumped Vulture Gyps bengalensis and Slender-billed Vulture Gyps tenuirostris in Nepal, both of which are also known to be highly sensitive to diclofenac. Since 2006, the veterinary use of diclofenac has been banned in Nepal to prevent further vulture declines. In this paper, we analyse the population trend in Himalayan Griffon in Upper Mustang between 2002 and 2014 and show a partial recovery. We conclude that the decline is now occurring at a slower rate than previously observed and immigration from areas where diclofenac was either not or rarely used the probable explanation for the recovery observed.

Continuing mortality of vultures in India associated with illegal veterinary use of diclofenac and a potential threat from nimesulide

AbstractThe collapse of South Asia's Gyps vulture populations is attributable to the veterinary use of the non-steroidal anti-inflammatory drug (NSAID) diclofenac. Vultures died after feeding on carcasses of recently-medicated animals. The governments of India, Nepal and Pakistan banned the veterinary use of diclofenac in 2006. We analysed results of 62 necropsies and 48 NSAID assays of liver and/or kidney for vultures of five species found dead in India between 2000 and 2012. Visceral gout and diclofenac were detected in vultures from nine states and three species: Gyps bengalensis, Gyps indicus and Gyps himalayensis. Visceral gout was found in every vulture carcass in which a measurable level of diclofenac was detected. Meloxicam, an NSAID of low toxicity to vultures, was found in two vultures and nimesulide in five vultures. Nimesulide at elevated tissue concentrations was associated with visceral gout in four of these cases, always without diclofenac, suggesting that nimesulide may have similar toxic effects to those of diclofenac. Residues of meloxicam on its own were never associated with visceral gout. The proportion of Gyps vultures found dead in the wild in India with measurable levels of diclofenac in their tissues showed a modest and non-significant decline since the ban on the veterinary use of diclofenac. The prevalence of visceral gout declined less, probably because some cases of visceral gout from 2008 onwards were associated with nimesulide rather than diclofenac. Veterinary use of nimesulide is a potential threat to the recovery of vulture populations.

Have population declines in Egyptian Vulture and Red-headed Vulture in India slowed since the 2006 ban on veterinary diclofenac?

SummaryPopulations of three vulture species of the genus Gyps, the Egyptian Vulture Neophron percnopterus and Red-headed Vulture Sarcogyps calvus have declined markedly on the Indian subcontinent since the mid-1990s and all are now Critically Endangered or Endangered. Gyps vultures have been killed by the widely used non-steroidal anti-inflammatory drug diclofenac, ingested when they feed on carcasses of domesticated ungulates treated with the drug shortly before death. However, it is not known whether Egyptian Vulture and Red-headed Vulture are also sensitive to diclofenac. Veterinary use of diclofenac was banned in India in 2006. Since then, the prevalence and concentration of diclofenac in domesticated ungulates carcasses has decreased and population declines of Gyps vultures have slowed or reversed. Here, we examine counts of Egyptian and Red-headed Vultures obtained on road transects in and near protected areas between 1992 and 2011. We found indications that the declines in both species appear to have slowed and possibly increased after the ban was introduced, though the small numbers of birds counted make this conclusion less robust than that for the Gyps species. These results suggest that both species may have been adversely impacted by diclofenac and that government bans on this drug, which are beginning to take effect, may benefit a wider range of vulture species in the Indian subcontinent than was previously thought.

Implementing Ecopharmacovigilance in Practice: Challenges and Potential Opportunities

Ecopharmacovigilance (EPV) is a developing science and it is currently very unclear what it might mean in practice. We have performed a comparison between pharmacovigilance (PV) and EPV and have identified that there are similarities, but also some important differences that must be considered before any practical implementation of EPV. The biggest difference and greatest challenge concerns signal detection in the environment and the difficulty of identifying cause and effect. We reflect on the dramatic vulture decline in Asia, which was caused by the veterinary use of diclofenac, versus the relative difficulty in identifying the specific causes of intersex fish in European rivers. We explore what EPV might mean in practice and have identified that there are some practical measures that can be taken to assess environmental risks across product life cycle, particularly after launch of a new drug, to ensure that our risk assessments and scientific understanding of pharmaceuticals in the environment remain scientifically and ecologically relevant. These include:Tracking environmental risks after launch of the product, via literature monitoring for emerging data on exposure and effectsUsing Environmental Risk Management Plans (ERMPs) as a centralized resource to assess and manage the risks of a drug throughout its life cycleFurther research, testing or monitoring in the environment when a risk is identifiedKeeping a global EPV perspectiveIncreasing transparency and availability of environmental data for medicinal products.These measures will help to ensure that any significant environmental issues associated with pharmaceuticals in the environment (PIE) are identified in a timely way, and can be managed appropriately.

The Population Decline of Gyps Vultures in India and Nepal Has Slowed since Veterinary Use of Diclofenac was Banned

Populations of oriental white-backed vulture (Gyps bengalensis), long-billed vulture (Gyps indicus) and slender-billed vulture (Gyps tenuirostris) crashed during the mid-1990s throughout the Indian subcontinent. Surveys in India, initially conducted in 1991–1993 and repeated in 2000, 2002, 2003 and 2007, revealed that the population of Gyps bengalensis had fallen by 2007 to 0.1% of its numbers in the early 1990s, with the population of Gyps indicus and G. tenuirostris combined having fallen to 3.2% of its earlier level. A survey of G. bengalensis in western Nepal indicated that the size of the population in 2009 was 25% of that in 2002. In this paper, repeat surveys conducted in 2011 were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level, but the decline had slowed and may even have reversed for G. bengalensis, both in India and Nepal. However, estimates of the most recent population trends are imprecise, so it is possible that declines may be continuing, though at a significantly slower rate. The degree to which the decline of G. bengalensis in India has slowed is consistent with the expected effects on population trend of a measured change in the level of contamination of ungulate carcasses with the drug diclofenac, which is toxic to vultures, following a ban on its veterinary use in 2006. The most recent available information indicates that the elimination of diclofenac from the vultures’ food supply is incomplete, so further efforts are required to fully implement the ban.

Ensuring applied ecology has impact

Ensuring applied ecology has impact E. J. Milner-Gulland*, Jos Barlow, Marc W. Cadotte, Philip E. Hulme, Gillian Kerby and Mark J. Whittingham Department of Life Sciences, Imperial College London, Silwood Park, Buckhurst Road, Ascot, SL5 7PY, UK; Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK; Department of Biological Sciences, University of Toronto, Scarborough, ON, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada; Bio-Protection Research Centre, PO Box 84, Lincoln University, Canterbury, New Zealand; British Ecological Society, Charles Darwin House, 12 Roger Street, London WC1N 2JU, UK; and School of Biology, Ridley Building, Newcastle University, Newcastle-Upon-Tyne, NE1 7RU, UK

Effectiveness of Action in India to Reduce Exposure of Gyps Vultures to the Toxic Veterinary Drug Diclofenac

Contamination of their carrion food supply with the non-steroidal anti-inflammatory drug diclofenac has caused rapid population declines across the Indian subcontinent of three species of Gyps vultures endemic to South Asia. The governments of India, Pakistan and Nepal took action in 2006 to prevent the veterinary use of diclofenac on domesticated livestock, the route by which contamination occurs. We analyse data from three surveys of the prevalence and concentration of diclofenac residues in carcasses of domesticated ungulates in India, carried out before and after the implementation of a ban on veterinary use. There was little change in the prevalence and concentration of diclofenac between a survey before the ban and one conducted soon after its implementation, with the percentage of carcasses containing diclofenac in these surveys estimated at 10.8 and 10.7%, respectively. However, both the prevalence and concentration of diclofenac had fallen markedly 7–31 months after the implementation of the ban, with the true prevalence in this third survey estimated at 6.5%. Modelling of the impact of this reduction in diclofenac on the expected rate of decline of the oriental white-backed vulture (Gyps bengalensis) in India indicates that the decline rate has decreased to 40% of the rate before the ban, but is still likely to be rapid (about 18% year−1). Hence, further efforts to remove diclofenac from vulture food are still needed if the future recovery or successful reintroduction of vultures is to be feasible.

Decline of Vultures in Asia

The random samples item “Vulture Culture” (3 Feb., p. [587][1]) presents the appearance of large numbers of Eurasian griffon vultures in Rajasthan, India, as good news, but this is far from the case. In India, populations of three species of vultures endemic to South Asia (oriental white-backed, long-billed, and slender-billed) have declined to less than 3% of what they were about a decade ago and the decline continues ([1][2]). The Eurasian griffons are mostly immature birds from Central Asia, Tibet, and Mongolia that return there to breed, probably attracted in larger numbers by plentiful supplies of livestock carcasses left uneaten now that the resident species have almost disappeared. There is now substantial published evidence that the cause of the Asian vulture decline is veterinary use of the drug diclofenac, which vultures take in when they feed on the carcass of a cow or water buffalo treated with the drug ([1][2]–[3][3]). Eurasian griffons are as susceptible to kidney failure caused by diclofenac as their Asian relatives ([4][4]), so it is likely that the source populations of this species that winter in India will also be affected. Such an effect will not be detected soon, however, because there is virtually no systematic monitoring of numbers of vultures breeding in these inaccessible areas. Numbers of immature Eurasian griffons wintering in India may continue to grow, but this will probably just indicate a growing drain on their source populations. A ban on the veterinary use of diclofenac, announced by the Indian prime minister in March 2005 ([5][5]), will therefore probably benefit Eurasian griffons as well as the resident species, but only if it can be implemented successfully. The Random Samples item also contained inaccuracies about recently published findings on the safety to vultures of meloxicam, an alternative to diclofenac that could help to save the vultures by speeding the removal of diclofenac from their food supply ([6][6]). The vultures used in the experiments were captive, but not captive-bred, and 72 birds (not 35) were treated, of which 66 were given meloxicam itself, rather than meat from treated cattle. 1. 1.[↵][7]1. R. E. Green 2. et al. , J. Appl. Ecol. (2004)41, 793. 2. 2.1. J. L. Oaks 2. et al. , Nature (2004)427, 630. 3. 3.[↵][8]1. S. Shultz 2. et al. , Proc. R. Soc. London Ser. B (Suppl.) (2004)271, S458. DOI 10.1098/rsbl.2004.0223. 4. 4.[↵][9]1. G. E. Swan 2. et al. , Biol. Lett. (2006)doi:10.1098/rsbl.2005.0425 9. 5. 5.[↵][10]1. P. Bagla , Science (2005)307, 1851. 6. 6.[↵][11]1. G.E. Swan 2. et al. , PloS Biol. (2006)4 (no. 3), e66. [1]: /lookup/doi/10.1126/science.311.5761.587a [2]: #ref-1 [3]: #ref-3 [4]: #ref-4 [5]: #ref-5 [6]: #ref-6 [7]: #xref-ref-1-1 View reference 1. in text [8]: #xref-ref-3-1 View reference 3. in text [9]: #xref-ref-4-1 View reference 4. in text [10]: #xref-ref-5-1 View reference 5. in text [11]: #xref-ref-6-1 View reference 6. in text

Removing the Threat of Diclofenac to Critically Endangered Asian Vultures

Veterinary use of the nonsteroidal anti-inflammatory (NSAID) drug diclofenac in South Asia has resulted in the collapse of populations of three vulture species of the genusGyps to the most severe category of global extinction risk. Vultures are exposed to diclofenac when scavenging on livestock treated with the drug shortly before death. Diclofenac causes kidney damage, increased serum uric acid concentrations, visceral gout, and death. Concern about this issue led the Indian Government to announce its intention to ban the veterinary use of diclofenac by September 2005. Implementation of a ban is still in progress late in 2005, and to facilitate this we sought potential alternative NSAIDs by obtaining information from captive bird collections worldwide. We found that the NSAID meloxicam had been administered to 35 captiveGyps vultures with no apparent ill effects. We then undertook a phased programme of safety testing of meloxicam on the African white-backed vultureGyps africanus, which we had previously established to be as susceptible to diclofenac poisoning as the endangered AsianGyps vultures. We estimated the likely maximum level of exposure (MLE) of wild vultures and dosed birds by gavage (oral administration) with increasing quantities of the drug until the likely MLE was exceeded in a sample of 40G. africanus. Subsequently, sixG. africanus were fed tissues from cattle which had been treated with a higher than standard veterinary course of meloxicam prior to death. In the final phase, ten Asian vultures of two of the endangered species(Gyps bengalensis,Gyps indicus) were dosed with meloxicam by gavage; five of them at more than the likely MLE dosage. All meloxicam-treated birds survived all treatments, and none suffered any obvious clinical effects. Serum uric acid concentrations remained within the normal limits throughout, and were significantly lower than those from birds treated with diclofenac in other studies. We conclude that meloxicam is of low toxicity toGyps vultures and that its use in place of diclofenac would reduce vulture mortality substantially in the Indian subcontinent. Meloxicam is already available for veterinary use in India.

Systematics within Gyps vultures: a clade at risk

BackgroundPopulations of the Oriental White-backed Vulture (Gyps bengalensis) have declined by over 95% within the past decade. This decline is largely due to incidental consumption of the non-steroidal anti-inflammatory veterinary pharmaceutical diclofenac, commonly used to treat domestic livestock. The conservation status of other Gyps vultures in southern Asia is also of immediate concern, given the lack of knowledge regarding status of their populations and the continuing existence of taxonomic uncertainties. In this study, we assess phylogenetic relationships for all recognized species and the majority of subspecies within the genus Gyps. The continuing veterinary use of diclofenac is an unknown but potential risk to related species with similar feeding habits to Gyps bengalensis. Therefore, an accurate assessment of the phylogenetic relationships among Gyps vultures should aid in their conservation by clarifying taxonomic uncertainties, and enabling inference of their respective relatedness to susceptible G. bengalensis.ResultsPhylogenetic results using mitochondrial cytB, ND2 and control region sequence data indicate a recent and rapid diversification within the genus Gyps. All recognized species formed monophyletic groups with high statistical support, with the exception of the Eurasian Vulture, for which specimens identified as subspecies G. fulvus fulvescens appear closely related to the Himalayan Vulture (G. himalayensis). In all analyses, the earliest divergence separated the Oriental White-backed Vulture from other Gyps taxa, with the next diverging taxon being either the African White-backed Vulture (G. africanus), or the Himalayan Vulture. All analyses supported a sister relationship between the Eurasian Vulture (G. f. fulvus), and Rüppell's Vulture (G. rueppellii), with this clade being sister to another consisting of the two taxa of "Long-billed" Vulture (G. indicus indicus and G. i. tenuirostris), and the Cape Vulture (G. coprotheres). These molecular phylogenies strongly support the treatment of indicus and tenuirostris as separate species, as does morphological data showing that these two taxa of similar overall size differ in proportions, especially in rostral, alar, and pedal characters. In addition, grouping of bengalensis and africanus together in the genus Pseudogyps, as historically proposed, is not upheld based on mitochondrial data.ConclusionBoth molecular and morphological data provide strong support for considering the "Long-billed" Vulture to be comprised of two species (G. indicus and G. tenuirostris), and further analysis is warranted to determine the taxonomic distinctiveness of G. f. fulvescens. Our phylogenetic analyses and conservative estimates suggest the diversification of Gyps taxa to be within the past 6 million years. Diclofenac susceptibility has been previously demonstrated for four Gyps species (G. indicus, G. fulvus, G. africanus, G. bengalensis), and the phylogenetic position of these species each forming a sister relationship with at least one of the remaining species, support concern that other Gyps taxa may be susceptible as well. Determining genetic and evolutionary distinctiveness for Gyps lineages is increasingly important as a breeding program is being established to prevent extinction.

Diclofenac poisoning is widespread in declining vulture populations across the Indian subcontinent

Recent declines in the populations of three species of vultures in the Indian subcontinent are among the most rapid ever recorded in any bird species. Evidence from a previous study of one of these species, Gyps bengalensis, in the Punjab province of Pakistan, strongly implicates mortality caused by ingestion of residues of the veterinary non-steroidal anti-inflammatory drug diclofenac as the major cause of the decline. We show that a high proportion of Gyps bengalensis and G. indicus found dead or dying in a much larger area of India and Nepal also have residues of diclofenac and visceral gout, a post-mortem finding that is strongly associated with diclofenac contamination in both species. Hence, veterinary use of diclofenac is likely to have been the major cause of the rapid vulture population declines across the subcontinent.