The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform
Mark A Taggart - One of the best experts on this subject based on the ideXlab platform.
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nsaids detected in iberian avian scavengers and carrion after diclofenac registration for veterinary use in spain
Environmental Pollution, 2020Co-Authors: Marta Herrerovillar, Mark A Taggart, Roser Velarde, Pablo R Camarero, Victor Bandeira, Carlos Fonseca, Ignasi Marco, Rafael MateoAbstract:Abstract Despite the now well recognised impact of diclofenac on vultures across the Indian subcontinent, this non-steroidal anti-inflammatory drug (NSAID) was registered in 2013 for livestock treatment in Spain, Europe’s main vulture stronghold. We assessed the risk of exposure to diclofenac and nine other NSAIDs in avian scavengers in the Iberian Peninsula (Spain and Portugal) after the onset of diclofenac commercialization. We sampled 228 livestock carcasses from vulture feeding sites, primarily pig (n = 156) and sheep (n = 45). We also sampled tissues of 389 avian scavenger carcasses (306 Eurasian griffon vultures, 15 cinereous vultures, 11 Egyptian vultures, 12 bearded vultures and 45 other facultative scavengers). Samples were analysed by liquid chromatography with mass spectrometry (LCMS). Seven livestock carcasses (3.07%) contained NSAID residues: flunixin (1.75%), ketoprofen, diclofenac and meloxicam (0.44% each). NSAID residues were only detected in sheep (4.44%) and pig (3.21%) carcasses. Fourteen dead avian scavengers (3.60%) had NSAID residues in kidney and liver, specifically flunixin (1.03%) and meloxicam (2.57%). Flunixin was associated with Visceral Gout and/or kidney damage in three (0.98%) dead Eurasian griffons. To date, diclofenac poisoning has not been observed in Spain and Portugal, however, flunixin would appear to pose an immediate and clear risk. This work supports the need for well managed carrion disposal, alongside appropriate risk labelling on veterinary NSAIDs and other pharmaceuticals potentially toxic to avian scavengers.
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continuing mortality of vultures in india associated with illegal veterinary use of diclofenac and a potential threat from nimesulide
Oryx, 2016Co-Authors: Richard J Cuthbert, Mark A Taggart, Mohini Saini, Anil Kumar Sharma, Mandar Kulkarni, Parag Deori, Sachin P Ranade, Rohan Shringarpure, Toby H Galligan, Rhys E. GreenAbstract:The 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.
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suspected flunixin poisoning of a wild eurasian griffon vulture from spain
Conservation Biology, 2015Co-Authors: Irene Zorrilla, Mark A Taggart, Rosa Martinez, Ngaio RichardsAbstract:Exposure to residues of the nonsteroidal anti-inflammatory drug (NSAID) diclofenac present in livestock carcasses has caused extensive declines in 3 Gyps vulture species across Asia. The carcass of a wild Eurasian Griffon Vulture (Gyps fulvus) was found in 2012 on an Andalucian (Spain) game hunting reserve and examined forensically. The bird had severe Visceral Gout, a finding consistent with Gyps vultures from Asia that have been poisoned by diclofenac. Liver and kidney samples from this Eurasian Griffon Vulture contained elevated flunixin (an NSAID) levels (median = 2.70 and 6.50 mg/kg, respectively). This is the first reported case of a wild vulture being exposed to and apparently killed by an NSAID outside Asia. It is also the first reported instance of mortality in the wild resulting from environmental exposure to an NSAID other than diclofenac.
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apparent tolerance of turkey vultures cathartes aura to the non steroidal anti inflammatory drug diclofenac
Environmental Toxicology and Chemistry, 2008Co-Authors: Barnett A Rattner, Mark A Taggart, Maria A Whitehead, Grace Gasper, Carol U Meteyer, William A Link, Andrew A Meharg, Oliver H Pattee, Deborah J PainAbstract:The nonsteroidal anti-inflammatory drug diclofenac is extremely toxic to Old World Gyps vultures (median lethal dose ∼0.1–0.2 mg/kg), evoking Visceral Gout, renal necrosis, and mortality within a few days of exposure. Unintentional secondary poisoning of vultures that fed upon carcasses of diclofenac-treated livestock decimated populations in the Indian subcontinent. Because of the widespread use of diclofenac and other cyclooxygenase-2 inhibiting drugs, a toxicological study was undertaken in turkey vultures (Cathartes aura) as an initial step in examining sensitivity of New World scavenging birds. Two trials were conducted entailing oral gavage of diclofenac at doses ranging from 0.08 to 25 mg/kg body weight. Birds were observed for 7 d, blood samples were collected for plasma chemistry (predose and 12, 24, and 48 h and 7 d postdose), and select individuals were necropsied. Diclofenac failed to evoke overt signs of toxicity, Visceral Gout, renal necrosis, or elevate plasma uric acid at concentrations greater than 100 times the estimated median lethal dose reported for Gyps vultures. For turkey vultures receiving 8 or 25 mg/kg, the plasma half-life of diclofenac was estimated to be 6 h, and it was apparently cleared after several days as no residues were detectable in liver or kidney at necropsy. Differential sensitivity among avian species is a hallmark of cyclooxygenase-2 inhibitors, and despite the tolerance of turkey vultures to diclofenac, additional studies in related scavenging species seem warranted.
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removing the threat of diclofenac to critically endangered asian vultures
PLOS Biology, 2006Co-Authors: G E Swan, Vinasan Naidoo, Richard J Cuthbert, Deborah J Pain, Devendra Swarup, Vibhu Prakash, Mark A Taggart, Rhys E. Green, Lizette C BekkerAbstract: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.
Deborah J Pain - One of the best experts on this subject based on the ideXlab platform.
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apparent tolerance of turkey vultures cathartes aura to the non steroidal anti inflammatory drug diclofenac
Environmental Toxicology and Chemistry, 2008Co-Authors: Barnett A Rattner, Mark A Taggart, Maria A Whitehead, Grace Gasper, Carol U Meteyer, William A Link, Andrew A Meharg, Oliver H Pattee, Deborah J PainAbstract:The nonsteroidal anti-inflammatory drug diclofenac is extremely toxic to Old World Gyps vultures (median lethal dose ∼0.1–0.2 mg/kg), evoking Visceral Gout, renal necrosis, and mortality within a few days of exposure. Unintentional secondary poisoning of vultures that fed upon carcasses of diclofenac-treated livestock decimated populations in the Indian subcontinent. Because of the widespread use of diclofenac and other cyclooxygenase-2 inhibiting drugs, a toxicological study was undertaken in turkey vultures (Cathartes aura) as an initial step in examining sensitivity of New World scavenging birds. Two trials were conducted entailing oral gavage of diclofenac at doses ranging from 0.08 to 25 mg/kg body weight. Birds were observed for 7 d, blood samples were collected for plasma chemistry (predose and 12, 24, and 48 h and 7 d postdose), and select individuals were necropsied. Diclofenac failed to evoke overt signs of toxicity, Visceral Gout, renal necrosis, or elevate plasma uric acid at concentrations greater than 100 times the estimated median lethal dose reported for Gyps vultures. For turkey vultures receiving 8 or 25 mg/kg, the plasma half-life of diclofenac was estimated to be 6 h, and it was apparently cleared after several days as no residues were detectable in liver or kidney at necropsy. Differential sensitivity among avian species is a hallmark of cyclooxygenase-2 inhibitors, and despite the tolerance of turkey vultures to diclofenac, additional studies in related scavenging species seem warranted.
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The race to prevent the extinction of South Asian vultures. Bird Conservation International 18:S30-S48
2008Co-Authors: Deborah J Pain, Ram D Jakati, Martin Gilbert, Christopher G. R. Bowden, Andrew A, Richard Cuthbert, Devojit Das, Yadvendradev Jhala, Aleem A. Khan, Lindsay J OaksAbstract:Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had Visceral Gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Consequently, it may be some years before diclofenac is removed from the vultures ’ food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes
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removing the threat of diclofenac to critically endangered asian vultures
PLOS Biology, 2006Co-Authors: G E Swan, Vinasan Naidoo, Richard J Cuthbert, Deborah J Pain, Devendra Swarup, Vibhu Prakash, Mark A Taggart, Rhys E. Green, Lizette C BekkerAbstract: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.
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diclofenac poisoning is widespread in declining vulture populations across the indian subcontinent
Proceedings of The Royal Society B: Biological Sciences, 2004Co-Authors: Susanne Shultz, Rhys E. Green, Hem Sagar Baral, Sheonaidh Charman, Andrew A Cunningham, Govind R Ghalsasi, Mallikarjun S Goudar, Ainsley Jones, Prashant K Nighot, Deborah J PainAbstract: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.
Lindsay J Oaks - One of the best experts on this subject based on the ideXlab platform.
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The race to prevent the extinction of South Asian vultures. Bird Conservation International 18:S30-S48
2008Co-Authors: Deborah J Pain, Ram D Jakati, Martin Gilbert, Christopher G. R. Bowden, Andrew A, Richard Cuthbert, Devojit Das, Yadvendradev Jhala, Aleem A. Khan, Lindsay J OaksAbstract:Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had Visceral Gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Consequently, it may be some years before diclofenac is removed from the vultures ’ food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes
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rapid population declines and mortality clusters in three oriental white backed vulture gyps bengalensis colonies in pakistan due to diclofenac poisoning
Oryx, 2006Co-Authors: Martin Gilbert, Lindsay J Oaks, Muhammad Jamshed Iqbal Chaudhry, Munir Z. Virani, Richard T. Watson, Shahid Mahmood, Muhammad Arshad, Shakeel Ahmed, Aleem Ahmed KhanAbstract:The population declines affecting Asian Gyps vultures are among the most rapid and geographically widespread recorded for any species. This paper describes the rates and patterns of mortality and population change over 4 years at three Oriental white-backed vulture Gyps bengalensis colonies in Pakistan: Dholewala (initially 421 pairs), Toawala (initially 445 pairs) and Changa Manga (initially 758 pairs). Vulture mortality led to the extirpation of two of these colonies (Changa Manga and Dholewala) in 3 years, and a decline of 54.3% in the third. Visceral Gout, indicative of diclofenac poisoning, was the largest single cause of death in vultures examined. Annual adult mortality from diclofenac poisoning was significantly positively correlated with annual population declines at each colony indicating a direct causal relationship. Visceral Gout occurred in temporal and spatial clusters suggesting multiple point sources of diclofenac expo- sure. The spatial and temporal distribution of dead vultures and approximate time since death were used to estimate minimum rates at which colonies encountered carcasses with sufficient diclofenac to cause mortality of 1.26-1.88 carcasses per colony per month. By estimating total carcass consumption at each colony, the percentage of carcasses contaminated with diclofenac was calcu- lated as 1.41-3.02%, exceeding the minimum required to have caused the observed population decline. With populations declining by approximately 50% annually, the long term survival of Gyps vultures in South Asia will require the removal of diclofenac from vulture food and establishment of captive populations for future restoration once the environment is free from contam- ination.
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pathology and proposed pathophysiology of diclofenac poisoning in free living and experimentally exposed oriental white backed vultures gyps bengalensis
Journal of Wildlife Diseases, 2005Co-Authors: Carol U Meteyer, Martin Gilbert, Bruce A Rideout, H L Shivaprasad, Lindsay J OaksAbstract:Oriental white-backed vultures (Gyps bengalensis; OWBVs) died of renal failure when they ingested diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), in tissues of domestic livestock. Acute necrosis of proximal convoluted tubules in these vultures was severe. Glomeruli, distal convoluted tubules, and collecting tubules were relatively spared in the vultures that had early lesions. In most vultures, however, lesions became extensive with large urate aggregates obscuring renal architecture. Inflammation was minimal. Extensive urate precipitation on the surface and within organ parenchyma (Visceral Gout) was consistently found in vultures with renal failure. Very little is known about the physiologic effect of NSAIDs in birds. Research in mammals has shown that diclofenac inhibits formation of prostaglandins. We propose that the mechanism by which diclofenac induces renal failure in the OWBV is through the inhibition of the modulating effect of prostaglandin on angiotensin II-mediated adrenergic stimu...
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diclofenac residues as the cause of vulture population decline in pakistan
Nature, 2004Co-Authors: Lindsay J Oaks, Muhammad Jamshed Iqbal Chaudhry, Munir Z. Virani, Richard T. Watson, Martin Gilbert, Shakeel Ahmed, Carol U Meteyer, Bruce A Rideout, H L Shivaprasad, Muhammad ArshadAbstract:The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent1. A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India2. Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent3. Consequently these vultures are now listed as critically endangered by BirdLife International4. In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh–Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites5. Between 2000 and 2003, high annual adult and subadult mortality (5–86%) and resulting population declines (34–95%) (ref. 5 and M.G., manuscript in preparation) were associated with renal failure and Visceral Gout. Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure. Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock. We propose that residues of veterinary diclofenac are responsible for the OWBV decline.
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breeding and mortality of oriental white backed vulture gyps bengalensis in punjab province pakistan
Bird Conservation International, 2002Co-Authors: Martin Gilbert, Lindsay J Oaks, Aleem Ahmed Khan, Munir Z. Virani, Richard T. Watson, Muhammad Arshad, Shakeel Ahmed, Patrick C Benson, Jamshed Chaudhry, Shahid MahmoodAbstract:Populations of Oriental White-backed Vulture Gyps bengalensis and Long-billed Vulture G. indicus declined in India between the mid 1980s and late 1990s. Regional reports from India described declines of 95–100% across a wide area. This study was conducted to investigate the breeding success and pattern of mortality in two vulture colonies (Dholewala and Changa Manga) within Punjab Province, Pakistan between December 2000 and June 2001. Breeding success was found to be 62% in Dholewala and 59% in Changa Manga. A total of 668 sick and dead vultures were collected of which 591 were less than one month post mortem . No significant variation was found in the weekly mortality rate of adult and subadult vultures during the study period spanning winter through summer. A peak in mortality rate was observed during late April and early May that corresponded to mortality of newly fledged juveniles. Minimum annual mortality rate in the adult breeding population was calculated to be 11.4% and 18.6% in Dholewala and Changa Manga respectively. In a subsample of dead vultures ( n = 185) Visceral Gout was found in 80% of adults, 63% of subadults, 19% of juveniles and 13% of nestlings. These mortality rates were consistent with a rapid population decline. Results imply that the mortality factor responsible for the decline in Gyps vultures described in India is also present in Pakistan and will potentially lead to a population decline of a comparable magnitude.
Carol U Meteyer - One of the best experts on this subject based on the ideXlab platform.
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apparent tolerance of turkey vultures cathartes aura to the non steroidal anti inflammatory drug diclofenac
Environmental Toxicology and Chemistry, 2008Co-Authors: Barnett A Rattner, Mark A Taggart, Maria A Whitehead, Grace Gasper, Carol U Meteyer, William A Link, Andrew A Meharg, Oliver H Pattee, Deborah J PainAbstract:The nonsteroidal anti-inflammatory drug diclofenac is extremely toxic to Old World Gyps vultures (median lethal dose ∼0.1–0.2 mg/kg), evoking Visceral Gout, renal necrosis, and mortality within a few days of exposure. Unintentional secondary poisoning of vultures that fed upon carcasses of diclofenac-treated livestock decimated populations in the Indian subcontinent. Because of the widespread use of diclofenac and other cyclooxygenase-2 inhibiting drugs, a toxicological study was undertaken in turkey vultures (Cathartes aura) as an initial step in examining sensitivity of New World scavenging birds. Two trials were conducted entailing oral gavage of diclofenac at doses ranging from 0.08 to 25 mg/kg body weight. Birds were observed for 7 d, blood samples were collected for plasma chemistry (predose and 12, 24, and 48 h and 7 d postdose), and select individuals were necropsied. Diclofenac failed to evoke overt signs of toxicity, Visceral Gout, renal necrosis, or elevate plasma uric acid at concentrations greater than 100 times the estimated median lethal dose reported for Gyps vultures. For turkey vultures receiving 8 or 25 mg/kg, the plasma half-life of diclofenac was estimated to be 6 h, and it was apparently cleared after several days as no residues were detectable in liver or kidney at necropsy. Differential sensitivity among avian species is a hallmark of cyclooxygenase-2 inhibitors, and despite the tolerance of turkey vultures to diclofenac, additional studies in related scavenging species seem warranted.
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pathology and proposed pathophysiology of diclofenac poisoning in free living and experimentally exposed oriental white backed vultures gyps bengalensis
Journal of Wildlife Diseases, 2005Co-Authors: Carol U Meteyer, Martin Gilbert, Bruce A Rideout, H L Shivaprasad, Lindsay J OaksAbstract:Oriental white-backed vultures (Gyps bengalensis; OWBVs) died of renal failure when they ingested diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), in tissues of domestic livestock. Acute necrosis of proximal convoluted tubules in these vultures was severe. Glomeruli, distal convoluted tubules, and collecting tubules were relatively spared in the vultures that had early lesions. In most vultures, however, lesions became extensive with large urate aggregates obscuring renal architecture. Inflammation was minimal. Extensive urate precipitation on the surface and within organ parenchyma (Visceral Gout) was consistently found in vultures with renal failure. Very little is known about the physiologic effect of NSAIDs in birds. Research in mammals has shown that diclofenac inhibits formation of prostaglandins. We propose that the mechanism by which diclofenac induces renal failure in the OWBV is through the inhibition of the modulating effect of prostaglandin on angiotensin II-mediated adrenergic stimu...
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diclofenac residues as the cause of vulture population decline in pakistan
Nature, 2004Co-Authors: Lindsay J Oaks, Muhammad Jamshed Iqbal Chaudhry, Munir Z. Virani, Richard T. Watson, Martin Gilbert, Shakeel Ahmed, Carol U Meteyer, Bruce A Rideout, H L Shivaprasad, Muhammad ArshadAbstract:The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent1. A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India2. Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent3. Consequently these vultures are now listed as critically endangered by BirdLife International4. In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh–Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites5. Between 2000 and 2003, high annual adult and subadult mortality (5–86%) and resulting population declines (34–95%) (ref. 5 and M.G., manuscript in preparation) were associated with renal failure and Visceral Gout. Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure. Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock. We propose that residues of veterinary diclofenac are responsible for the OWBV decline.
Martin Gilbert - One of the best experts on this subject based on the ideXlab platform.
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The race to prevent the extinction of South Asian vultures. Bird Conservation International 18:S30-S48
2008Co-Authors: Deborah J Pain, Ram D Jakati, Martin Gilbert, Christopher G. R. Bowden, Andrew A, Richard Cuthbert, Devojit Das, Yadvendradev Jhala, Aleem A. Khan, Lindsay J OaksAbstract:Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had Visceral Gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Consequently, it may be some years before diclofenac is removed from the vultures ’ food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes
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rapid population declines and mortality clusters in three oriental white backed vulture gyps bengalensis colonies in pakistan due to diclofenac poisoning
Oryx, 2006Co-Authors: Martin Gilbert, Lindsay J Oaks, Muhammad Jamshed Iqbal Chaudhry, Munir Z. Virani, Richard T. Watson, Shahid Mahmood, Muhammad Arshad, Shakeel Ahmed, Aleem Ahmed KhanAbstract:The population declines affecting Asian Gyps vultures are among the most rapid and geographically widespread recorded for any species. This paper describes the rates and patterns of mortality and population change over 4 years at three Oriental white-backed vulture Gyps bengalensis colonies in Pakistan: Dholewala (initially 421 pairs), Toawala (initially 445 pairs) and Changa Manga (initially 758 pairs). Vulture mortality led to the extirpation of two of these colonies (Changa Manga and Dholewala) in 3 years, and a decline of 54.3% in the third. Visceral Gout, indicative of diclofenac poisoning, was the largest single cause of death in vultures examined. Annual adult mortality from diclofenac poisoning was significantly positively correlated with annual population declines at each colony indicating a direct causal relationship. Visceral Gout occurred in temporal and spatial clusters suggesting multiple point sources of diclofenac expo- sure. The spatial and temporal distribution of dead vultures and approximate time since death were used to estimate minimum rates at which colonies encountered carcasses with sufficient diclofenac to cause mortality of 1.26-1.88 carcasses per colony per month. By estimating total carcass consumption at each colony, the percentage of carcasses contaminated with diclofenac was calcu- lated as 1.41-3.02%, exceeding the minimum required to have caused the observed population decline. With populations declining by approximately 50% annually, the long term survival of Gyps vultures in South Asia will require the removal of diclofenac from vulture food and establishment of captive populations for future restoration once the environment is free from contam- ination.
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pathology and proposed pathophysiology of diclofenac poisoning in free living and experimentally exposed oriental white backed vultures gyps bengalensis
Journal of Wildlife Diseases, 2005Co-Authors: Carol U Meteyer, Martin Gilbert, Bruce A Rideout, H L Shivaprasad, Lindsay J OaksAbstract:Oriental white-backed vultures (Gyps bengalensis; OWBVs) died of renal failure when they ingested diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), in tissues of domestic livestock. Acute necrosis of proximal convoluted tubules in these vultures was severe. Glomeruli, distal convoluted tubules, and collecting tubules were relatively spared in the vultures that had early lesions. In most vultures, however, lesions became extensive with large urate aggregates obscuring renal architecture. Inflammation was minimal. Extensive urate precipitation on the surface and within organ parenchyma (Visceral Gout) was consistently found in vultures with renal failure. Very little is known about the physiologic effect of NSAIDs in birds. Research in mammals has shown that diclofenac inhibits formation of prostaglandins. We propose that the mechanism by which diclofenac induces renal failure in the OWBV is through the inhibition of the modulating effect of prostaglandin on angiotensin II-mediated adrenergic stimu...
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diclofenac residues as the cause of vulture population decline in pakistan
Nature, 2004Co-Authors: Lindsay J Oaks, Muhammad Jamshed Iqbal Chaudhry, Munir Z. Virani, Richard T. Watson, Martin Gilbert, Shakeel Ahmed, Carol U Meteyer, Bruce A Rideout, H L Shivaprasad, Muhammad ArshadAbstract:The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent1. A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India2. Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent3. Consequently these vultures are now listed as critically endangered by BirdLife International4. In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh–Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites5. Between 2000 and 2003, high annual adult and subadult mortality (5–86%) and resulting population declines (34–95%) (ref. 5 and M.G., manuscript in preparation) were associated with renal failure and Visceral Gout. Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure. Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock. We propose that residues of veterinary diclofenac are responsible for the OWBV decline.
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breeding and mortality of oriental white backed vulture gyps bengalensis in punjab province pakistan
Bird Conservation International, 2002Co-Authors: Martin Gilbert, Lindsay J Oaks, Aleem Ahmed Khan, Munir Z. Virani, Richard T. Watson, Muhammad Arshad, Shakeel Ahmed, Patrick C Benson, Jamshed Chaudhry, Shahid MahmoodAbstract:Populations of Oriental White-backed Vulture Gyps bengalensis and Long-billed Vulture G. indicus declined in India between the mid 1980s and late 1990s. Regional reports from India described declines of 95–100% across a wide area. This study was conducted to investigate the breeding success and pattern of mortality in two vulture colonies (Dholewala and Changa Manga) within Punjab Province, Pakistan between December 2000 and June 2001. Breeding success was found to be 62% in Dholewala and 59% in Changa Manga. A total of 668 sick and dead vultures were collected of which 591 were less than one month post mortem . No significant variation was found in the weekly mortality rate of adult and subadult vultures during the study period spanning winter through summer. A peak in mortality rate was observed during late April and early May that corresponded to mortality of newly fledged juveniles. Minimum annual mortality rate in the adult breeding population was calculated to be 11.4% and 18.6% in Dholewala and Changa Manga respectively. In a subsample of dead vultures ( n = 185) Visceral Gout was found in 80% of adults, 63% of subadults, 19% of juveniles and 13% of nestlings. These mortality rates were consistent with a rapid population decline. Results imply that the mortality factor responsible for the decline in Gyps vultures described in India is also present in Pakistan and will potentially lead to a population decline of a comparable magnitude.
