The Experts below are selected from a list of 1578 Experts worldwide ranked by ideXlab platform
M. J. Dreyer - One of the best experts on this subject based on the ideXlab platform.
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immobilization of wild dogs Lycaon pictus with a tiletamine hydrochloride zolazepam hydrochloride combination and subsequent evaluation of selected blood chemistry parameters
Journal of Wildlife Diseases, 1991Co-Authors: J Van Heerden, R.e.j. Burroughs, J. Dauth, M. J. DreyerAbstract:A tiletamine hydrochloride/zolazepam hydrochloride combination was used successfully to immobilize captive untamed wild dogs (Lycaon pictus) (n = 16) at dosage rates ranging from 2.3 to 32.3 mg/kg. Animals remained immobilized for periods ranging from 35 min to 24 hr 14 min. There was a significant positive correlation (r = 0.85, P < 0.01) between dosage rate and the time immobilized. Profuse salivation and intermittent mild myoclonal contractions were observed in some wild dogs. Mildly reduced partial oxygen and carbon dioxide pressures as well as reduced concentrations of bicarbonate were observed in arterial blood at 10 and 20 min after administration of the drug. Serum concentrations of sodium, potassium, chloride, phosphorus, calcium, magnesium, urea, creatinine, glucose, proteins, albumin, gammaglutamyltransferase, creatinine kinase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase, insulin, Cortisol and thyroxine are presented. These concentrations were found to be in agreement w...
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Sedation and immobilization of wild dogs Lycaon pictus using medetomidine or a medetomidine-ketamine hydrochloride combination
South African Journal of Wildlife Research - 24-month delayed open access, 1991Co-Authors: J Van Heerden, G.e. Swan, J. Dauth, M. J. Dreyer, R.e.j. BurroughsAbstract:Captive wild dogs Lycaon pictus (n = 10) were treated with either medetomidine or a medetomidine-ketamine hydrochloride combination at dosages ranging from 43-121 µg / kg and 2,6-3 mg / kg respectively. Blood chemical, haematological, hormonal and electrocardiograpbic parameters as well as rectal temperatures, pulse and respiratory rates were determined in immobilized animals, Nine wild dogs were sedated and partially or completely immobilized for periods ranging from 25 min to 6 h 27 min. Full anaesthesia was not achieved, Bradycardia, a drop in respiratory rate as well as in rectal temperature were recorded in all immobilized experimental subjects. The most marked changes in clinical laboratory parameters in eight wild dogs included low serum concentrations of cortisol, adrenaline, noradrenaline, dopamine and insulin as well as raised plasma glucose concentrations, Electrocardiographic findings included brady-arrhythmias and ventricular escape beats. Medetomidine was found to be an effective sedative in wild dogs but should preferably be used in combination with ketamine to achieve effective immobilization, analgesia and anaesthesia. Wildehonde Lycaon pictus (n = 10) in gevangenskap is behandel met medetomidien of 'n medetomidienketamienhidrokloriedkombinasic teen dosisse van onderskeidelik 43-121 µg / kg en 2,6-3 mg / kg. Bloedchemiese, hematologiese, hormonale en elektrokardiografiese parameters sowel as die rektale temperatuur, pols- en asemhalingstempo's is bepaal in geimmobiliseerde diere. Nege wilde honde is gesedeer en gedeeltelik of totaal geimmobiliseer vir tydperke wat gevarieer het van 25 min tot 6 h 27 min. Die diere is nie ten volle verdoof nie. Bradikardie asook 'n daling in asemhalingstempo en rektale temperatuur is waargeneem in alle geimmobiliseerde eksperimentele diere. Die mees opvallende veranderinge in laboratoriumparameters in agt diere was 'n lae serumkonsentrasie van kortisol, adrenalien, noradrenalien, dopamien en insulien asook 'n verhoging in die konsentrasie van plasmaglukose. Elektrokardiografiese bevindings het 'n bradie-aritmie asook ventrikulere ontsnappings-sametrekkkings ingesluit. Medetomidien is as 'n effektiewe sedeermiddel in wilde honde bevind maar moet verkieslik met ketamien gebruik word ten einde doeltreffende immobilisasie, pynstilling en verdowing teweeg te bring.
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Immobilization of wild dogs (Lycaon pictus) with a tiletamine hydrochloride/zolazepam hydrochloride combination and subsequent evaluation of selected blood chemistry parameters.
Journal of Wildlife Diseases, 1991Co-Authors: J Van Heerden, R.e.j. Burroughs, J. Dauth, M. J. DreyerAbstract:A tiletamine hydrochloride/zolazepam hydrochloride combination was used successfully to immobilize captive untamed wild dogs (Lycaon pictus) (n = 16) at dosage rates ranging from 2.3 to 32.3 mg/kg. Animals remained immobilized for periods ranging from 35 min to 24 hr 14 min. There was a significant positive correlation (r = 0.85, P < 0.01) between dosage rate and the time immobilized. Profuse salivation and intermittent mild myoclonal contractions were observed in some wild dogs. Mildly reduced partial oxygen and carbon dioxide pressures as well as reduced concentrations of bicarbonate were observed in arterial blood at 10 and 20 min after administration of the drug. Serum concentrations of sodium, potassium, chloride, phosphorus, calcium, magnesium, urea, creatinine, glucose, proteins, albumin, gammaglutamyltransferase, creatinine kinase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase, insulin, Cortisol and thyroxine are presented. These concentrations were found to be in agreement w...
Joan B. Silk - One of the best experts on this subject based on the ideXlab platform.
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Pup production, sex ratios, and survivorship in African wild dogs, Lycaon pictus
Behavioral Ecology and Sociobiology, 2008Co-Authors: J. Weldon Mcnutt, Joan B. SilkAbstract:The local resource enhancement (LRE) model predicts that in cooperatively breeding species, sex ratios will be biased in favor of the more helpful sex. In this study, we assess the assumptions underlying the LRE model in a population of cooperatively breeding wild dogs ( Lycaon pictus ) in Northern Botswana monitored over a 15-year period. In this population, litter size and pup survival to 1 year are strongly affected by pack size and the breeding female’s age, but adult males have a stronger and more linear effect on females’ reproductive performance than do adult females. This asymmetry in the benefits derived from male and female helpers is reflected in male-biased sex ratios in litters at the time pups emerge from the den. Sex ratio biases are most pronounced in the litters of the youngest mothers who live in significantly smaller packs than older females. The presence of potential rivals for the dominant female’s position depresses pup production at the time of emergence, suggesting that competition among females for breeding positions may also contribute to the selective forces affecting birth sex ratios.
Melissa T R Hawkins - One of the best experts on this subject based on the ideXlab platform.
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genome sequence population history and pelage genetics of the endangered african wild dog Lycaon pictus
BMC Genomics, 2016Co-Authors: Lillian D Parker, Michael G Campana, Melissa T R Hawkins, Hillary S Young, Kristofer HelgenAbstract:The African wild dog (Lycaon pictus) is an endangered African canid threatened by severe habitat fragmentation, human-wildlife conflict, and infectious disease. A highly specialized carnivore, it is distinguished by its social structure, dental morphology, absence of dewclaws, and colorful pelage. We sequenced the genomes of two individuals from populations representing two distinct ecological histories (Laikipia County, Kenya and KwaZulu-Natal Province, South Africa). We reconstructed population demographic histories for the two individuals and scanned the genomes for evidence of selection. We show that the African wild dog has undergone at least two effective population size reductions in the last 1,000,000 years. We found evidence of Lycaon individual-specific regions of low diversity, suggestive of inbreeding or population-specific selection. Further research is needed to clarify whether these population reductions and low diversity regions are characteristic of the species as a whole. We documented positive selection on the Lycaon mitochondrial genome. Finally, we identified several candidate genes (ASIP, MITF, MLPH, PMEL) that may play a role in the characteristic Lycaon pelage.
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Genome sequence, population history, and pelage genetics of the endangered African wild dog (Lycaon pictus).
eScholarship University of California, 2016Co-Authors: Campana, Michael G, Melissa T R Hawkins, Parker, Lillian D, Young, Hillary S, Helgen, Kristofer M, Szykman Gunther Micaela, Woodroffe Rosie, Maldonado, Jesús E, Fleischer, Robert CAbstract:BACKGROUND:The African wild dog (Lycaon pictus) is an endangered African canid threatened by severe habitat fragmentation, human-wildlife conflict, and infectious disease. A highly specialized carnivore, it is distinguished by its social structure, dental morphology, absence of dewclaws, and colorful pelage. RESULTS:We sequenced the genomes of two individuals from populations representing two distinct ecological histories (Laikipia County, Kenya and KwaZulu-Natal Province, South Africa). We reconstructed population demographic histories for the two individuals and scanned the genomes for evidence of selection. CONCLUSIONS:We show that the African wild dog has undergone at least two effective population size reductions in the last 1,000,000 years. We found evidence of Lycaon individual-specific regions of low diversity, suggestive of inbreeding or population-specific selection. Further research is needed to clarify whether these population reductions and low diversity regions are characteristic of the species as a whole. We documented positive selection on the Lycaon mitochondrial genome. Finally, we identified several candidate genes (ASIP, MITF, MLPH, PMEL) that may play a role in the characteristic Lycaon pelage
Lillian D Parker - One of the best experts on this subject based on the ideXlab platform.
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genome sequence population history and pelage genetics of the endangered african wild dog Lycaon pictus
BMC Genomics, 2016Co-Authors: Lillian D Parker, Michael G Campana, Melissa T R Hawkins, Hillary S Young, Kristofer HelgenAbstract:The African wild dog (Lycaon pictus) is an endangered African canid threatened by severe habitat fragmentation, human-wildlife conflict, and infectious disease. A highly specialized carnivore, it is distinguished by its social structure, dental morphology, absence of dewclaws, and colorful pelage. We sequenced the genomes of two individuals from populations representing two distinct ecological histories (Laikipia County, Kenya and KwaZulu-Natal Province, South Africa). We reconstructed population demographic histories for the two individuals and scanned the genomes for evidence of selection. We show that the African wild dog has undergone at least two effective population size reductions in the last 1,000,000 years. We found evidence of Lycaon individual-specific regions of low diversity, suggestive of inbreeding or population-specific selection. Further research is needed to clarify whether these population reductions and low diversity regions are characteristic of the species as a whole. We documented positive selection on the Lycaon mitochondrial genome. Finally, we identified several candidate genes (ASIP, MITF, MLPH, PMEL) that may play a role in the characteristic Lycaon pelage.
J Van Heerden - One of the best experts on this subject based on the ideXlab platform.
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Seroepidemiological survey of sympatric domestic and wild dogs (Lycaon pictus) in Tsumkwe District, north-eastern Namibia
The Onderstepoort journal of veterinary research, 1997Co-Authors: K. Laurenson, J Van Heerden, P. StanderAbstract:LAURENSON, K., VAN HEERDEN, J., STANDER, P. & VAN VUUREN, M.J. 1997. Seroepidemiological survey of sympatric domestic and wild dogs (Lycaon pictus) in Tsumkwe District, north-eastern Namibia. Onderstepoort Journal of Veterinary Research, 64:313-316 Disease is a potential threat to many endangered populations and may originate from sympatric domestic species. This paper describes a cross-sectional serological survey of canine pathogens carried out in domestic (n = 70) and wild dogs (Lycoan pictus) (n = 6) , in Tsumkwe District, north eastern Namibia. Evidence of past exposure to canine distemper virus, canine adenovirus and para influenza virus was evident in both wild and domestic dogs with this, the first, documented expo sure of free-living wild dogs to canine distemper. Domestic dogs were also exposed to rabies virus, canine parvovirus and coronavirus. There was no pathogen to which wild dogs, but not domestic dogs, were exposed. With wild dogs known to be susceptible to rabies and canine distemper, these may be the greatest threat to this population of wild dogs, although some wild dogs can clearly survive infection with canine distemper.
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Handling-Induced Stress and Mortalities in African Wild Dogs (Lycaon pictus)
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1995Co-Authors: M. S. De Villiers, J Van Heerden, D. G. A. Meltzer, Michael G. L. Mills, P. R. K. Richardson, A. S. Van JaarsveldAbstract:Recently it was suggested that the handling of wild dogs (Lycaon pictus) by researchers in the Serengeti ecosystem created stress, resulting in the reactivation of latent rabies viruses in carrier animals. We present data from ongoing studies on free-ranging and captive wild dogs elsewhere in Africa which do not support this hypothesis. Cortisol profiles suggest that immobilization of wild dogs does not cause the chronic stress required for stress-reactivation of latent viruses. Furthermore, there is no evidence of handling-related mortalities in wild dogs: the survivorship of unhandled and handled free-ranging wild dogs did not differ and no captive animals died within a year of handling (immobilization and/or vaccination against rabies). We suggest that the mortalities observed in Tanzania were due to an outbreak of a disease which rabies vaccination was unable to prevent. Intensive monitoring and active management research programmes on wild dogs are essential as without these, critically endangered wild dog populations have little hope of survival.
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Sedation and immobilization of wild dogs Lycaon pictus using medetomidine or a medetomidine-ketamine hydrochloride combination
South African Journal of Wildlife Research - 24-month delayed open access, 1991Co-Authors: J Van Heerden, G.e. Swan, J. Dauth, M. J. Dreyer, R.e.j. BurroughsAbstract:Captive wild dogs Lycaon pictus (n = 10) were treated with either medetomidine or a medetomidine-ketamine hydrochloride combination at dosages ranging from 43-121 µg / kg and 2,6-3 mg / kg respectively. Blood chemical, haematological, hormonal and electrocardiograpbic parameters as well as rectal temperatures, pulse and respiratory rates were determined in immobilized animals, Nine wild dogs were sedated and partially or completely immobilized for periods ranging from 25 min to 6 h 27 min. Full anaesthesia was not achieved, Bradycardia, a drop in respiratory rate as well as in rectal temperature were recorded in all immobilized experimental subjects. The most marked changes in clinical laboratory parameters in eight wild dogs included low serum concentrations of cortisol, adrenaline, noradrenaline, dopamine and insulin as well as raised plasma glucose concentrations, Electrocardiographic findings included brady-arrhythmias and ventricular escape beats. Medetomidine was found to be an effective sedative in wild dogs but should preferably be used in combination with ketamine to achieve effective immobilization, analgesia and anaesthesia. Wildehonde Lycaon pictus (n = 10) in gevangenskap is behandel met medetomidien of 'n medetomidienketamienhidrokloriedkombinasic teen dosisse van onderskeidelik 43-121 µg / kg en 2,6-3 mg / kg. Bloedchemiese, hematologiese, hormonale en elektrokardiografiese parameters sowel as die rektale temperatuur, pols- en asemhalingstempo's is bepaal in geimmobiliseerde diere. Nege wilde honde is gesedeer en gedeeltelik of totaal geimmobiliseer vir tydperke wat gevarieer het van 25 min tot 6 h 27 min. Die diere is nie ten volle verdoof nie. Bradikardie asook 'n daling in asemhalingstempo en rektale temperatuur is waargeneem in alle geimmobiliseerde eksperimentele diere. Die mees opvallende veranderinge in laboratoriumparameters in agt diere was 'n lae serumkonsentrasie van kortisol, adrenalien, noradrenalien, dopamien en insulien asook 'n verhoging in die konsentrasie van plasmaglukose. Elektrokardiografiese bevindings het 'n bradie-aritmie asook ventrikulere ontsnappings-sametrekkkings ingesluit. Medetomidien is as 'n effektiewe sedeermiddel in wilde honde bevind maar moet verkieslik met ketamien gebruik word ten einde doeltreffende immobilisasie, pynstilling en verdowing teweeg te bring.
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Immobilization of wild dogs (Lycaon pictus) with a tiletamine hydrochloride/zolazepam hydrochloride combination and subsequent evaluation of selected blood chemistry parameters.
Journal of Wildlife Diseases, 1991Co-Authors: J Van Heerden, R.e.j. Burroughs, J. Dauth, M. J. DreyerAbstract:A tiletamine hydrochloride/zolazepam hydrochloride combination was used successfully to immobilize captive untamed wild dogs (Lycaon pictus) (n = 16) at dosage rates ranging from 2.3 to 32.3 mg/kg. Animals remained immobilized for periods ranging from 35 min to 24 hr 14 min. There was a significant positive correlation (r = 0.85, P < 0.01) between dosage rate and the time immobilized. Profuse salivation and intermittent mild myoclonal contractions were observed in some wild dogs. Mildly reduced partial oxygen and carbon dioxide pressures as well as reduced concentrations of bicarbonate were observed in arterial blood at 10 and 20 min after administration of the drug. Serum concentrations of sodium, potassium, chloride, phosphorus, calcium, magnesium, urea, creatinine, glucose, proteins, albumin, gammaglutamyltransferase, creatinine kinase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase, insulin, Cortisol and thyroxine are presented. These concentrations were found to be in agreement w...
