The Experts below are selected from a list of 192 Experts worldwide ranked by ideXlab platform
Desiré L. Dalton - One of the best experts on this subject based on the ideXlab platform.
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Molecular characterization in the toll-like receptor 9 gene of Cape Mountain Zebra (Equus Zebra Zebra) from three populations.
Infection genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases, 2019Co-Authors: Rae Marvin Smith, Antoinette Kotze, J. Paul Grobler, Desiré L. DaltonAbstract:Toll-like receptors (TLR) are a family of proteins that signal activation of the innate immune response through the recognition of a variety of pathogen molecular compounds. Here, we characterized the complete TLR9 gene in Cape Mountain Zebra (Equus Zebra Zebra) from three populations in South Africa and compared sequences to a variety of horse and donkey breeds. Overall, we identified six single nucleotide polymorpHisms (SNPs). A single SNP (G586S) was non-synonymous, whereas the remaining SNPs were synonymous. The G586S alteration was detected in Cape Mountain Zebra populations with varying frequency. In addition, adaptive diversity was found to be discordant with variation based on neutral markers. The mutation is unique to the Cape Mountain Zebra when compared to other equid species. The structure of TLR9 is relatively conserved and the resulting amino acid substitution was found to have minimal interaction with active sites in the protein. Future studies can explore the effects of this potentially functional mutation which will contribute to our understanding of genetic diversity within adaptive sites of the Cape Mountain Zebra genome.
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Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape Mountain Zebra (Equus Zebra Zebra)
PloS one, 2019Co-Authors: Antoinette Kotze, Yoshan Moodley, Rae Marvin Smith, Gordon Luikart, Coral Birss, Anna M. Van Wyk, J. Paul Grobler, Desiré L. DaltonAbstract:The Cape Mountain Zebra (Equus Zebra Zebra) is a subspecies of Mountain Zebra endemic to South Africa. The Cape Mountain Zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape Mountain Zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape Mountain Zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape Mountain Zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape Mountain Zebra, especially in the face of habitat and climate change and emerging diseases.
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Translocation a potential corridor for equine piroplasms in Cape Mountain Zebra (Equus Zebra Zebra).
International journal for parasitology. Parasites and wildlife, 2019Co-Authors: Rae Marvin Smith, Antoinette Kotze, J. Paul Grobler, Raksha Bhoora, Desiré L. DaltonAbstract:Translocation of animals in fragmented habitats is an important means of dispersal and gene flow, however, the movement of animals has led to the spread of various diseases globally and wildlife are often the reservoirs of these diseases. Currently, Cape Mountain Zebra are translocated within South Africa as a management method for augmentation of isolated and fragmented populations. The movement of pathogens due to translocations in local regions have gone largely unchecked, particularly where there may still be isolated regions that can be negatively affected. Equine piroplasmosis is a tick-borne disease caused by Theilaria equi and/or Babesia caballi reported to occur in equids (Bhoora et al., 2010; Zweygarth et al., 2002). Here, the presence of T. equi and B. caballi was detected in 137 clinically healthy Cape Mountain Zebra from three South African reserves, Mountain Zebra National Park (MZNP), De Hoop Nature Reserve (DHNR) and Karoo National Park (KNP) using the multiplex EP real-time PCR (qPCR) assay. We observed 100% prevalence for T. equi and identified only one animal from MZNP with B. caballi. These results affirm that precautions should be taken prior to founding new populations of Cape Mountain Zebra and that potential farms and properties adjacent to prospective reserves should be screened for the presence of the organisms in order to mitigate risks of infection to domestic animals.
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Hiding in Plain Sight: Evidence of Hybridization between Cape Mountain Zebra (Equus Zebra Zebra) and Plains Zebra (Equus quagga burchelli)
African Journal of Wildlife Research, 2017Co-Authors: Desiré L. Dalton, David Zimmermann, Clearance Mnisi, Megan Taplin, Peter Novellie, Halzska Hrabar, Antoinette KotzeAbstract:Historically, Cape Mountain Zebras (Equus Zebra Zebra) were widely distributed along Mountain ranges in the Eastern and Western Cape provinces of South Africa (Boshoff, Landman & Kerley, 2015). By the 1930s, excessive hunting and habitat loss resulted in a reduction in Cape Mountain Zebra numbers with populations being confined to only five localities. Two of these subpopulations subsequently became extinct. Three relic populations currently exist; the population in the Cradock district,was formally protected in 1937 by the proclamation of the Mountain Zebra National Park (MZNP; Lloyd 1984). The two other populations in the Kammanassie and Gamka Mountains, have been protected since 1923 and 1971, respectively. Cape Mountain Zebra numbers increased steadily from their critical status of fewer than 80 individuals in the 1950s, to an estimated minimum of 4791 individuals by 2015 (Hrabar & Kerley, 2015). Plains Zebra (Equus quagga burchelli) were subsequently introduced, in sympatry with Cape Mountain Zebra into four formally protected areas, including the MZNP in 1999 and Karoo National Park in 1998. Until recently no cases of hybridization between plains Zebra and Cape Mountain Zebra were known. Hybridization was not of great concern as a threat to Cape Mountain Zebra populations as fertile hybrids were thought to be unlikely, due to the relatively large difference in the number of chromosomal pairs between the two species (44 versus 32 in plains Zebra and Cape Mountain Zebra, respectively; Ryder, Epel & Benirschke, 1978; Cordingley et al., 2009; Hrabar & Kerley, 2013). By 2013, the plains Zebra population had increased substantially in the MZNP (estimated at 769 Cape Mountain Zebra and 124 plains Zebra by aerial census (unpublished aerial census data, 2013) and were potentially competing with Cape Mountain Zebra for resources. A decision was thus taken to remove the plains Zebra. This intervention resulted in a disruption in the social structure, and some of the small, fragmented groups or plains Zebra individuals joined Cape Mountain Zebra herds. In addition, conservation officials observed ‘Cape Mountain Zebra’ with plains Zebra characteristics. These included slight shadow striping, stripes extending all the way down to the ventral midline of the chest and abdomen, and, although they did have the reddish muzzle of Mountain Zebra, they did not have the characteristic Mountain Zebra gridiron pattern on their rumps (Fig. 1), but rather had absent or distorted patterns on the rump. They exhibited the distinct dewlap of the Cape Mountain Zebra and ear shapes were similar to plains Zebra. This raised concerns of possible hybridization between the two species. Here, we report on a molecular evaluation using maternal, paternal and biparental markers to identify suspected hybrid Cape Mountain and plains Zebra in MZNP and Karoo National Park, South Africa.
Antoinette Kotze - One of the best experts on this subject based on the ideXlab platform.
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Molecular characterization in the toll-like receptor 9 gene of Cape Mountain Zebra (Equus Zebra Zebra) from three populations.
Infection genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases, 2019Co-Authors: Rae Marvin Smith, Antoinette Kotze, J. Paul Grobler, Desiré L. DaltonAbstract:Toll-like receptors (TLR) are a family of proteins that signal activation of the innate immune response through the recognition of a variety of pathogen molecular compounds. Here, we characterized the complete TLR9 gene in Cape Mountain Zebra (Equus Zebra Zebra) from three populations in South Africa and compared sequences to a variety of horse and donkey breeds. Overall, we identified six single nucleotide polymorpHisms (SNPs). A single SNP (G586S) was non-synonymous, whereas the remaining SNPs were synonymous. The G586S alteration was detected in Cape Mountain Zebra populations with varying frequency. In addition, adaptive diversity was found to be discordant with variation based on neutral markers. The mutation is unique to the Cape Mountain Zebra when compared to other equid species. The structure of TLR9 is relatively conserved and the resulting amino acid substitution was found to have minimal interaction with active sites in the protein. Future studies can explore the effects of this potentially functional mutation which will contribute to our understanding of genetic diversity within adaptive sites of the Cape Mountain Zebra genome.
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Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape Mountain Zebra (Equus Zebra Zebra)
PloS one, 2019Co-Authors: Antoinette Kotze, Yoshan Moodley, Rae Marvin Smith, Gordon Luikart, Coral Birss, Anna M. Van Wyk, J. Paul Grobler, Desiré L. DaltonAbstract:The Cape Mountain Zebra (Equus Zebra Zebra) is a subspecies of Mountain Zebra endemic to South Africa. The Cape Mountain Zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape Mountain Zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape Mountain Zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape Mountain Zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape Mountain Zebra, especially in the face of habitat and climate change and emerging diseases.
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Translocation a potential corridor for equine piroplasms in Cape Mountain Zebra (Equus Zebra Zebra).
International journal for parasitology. Parasites and wildlife, 2019Co-Authors: Rae Marvin Smith, Antoinette Kotze, J. Paul Grobler, Raksha Bhoora, Desiré L. DaltonAbstract:Translocation of animals in fragmented habitats is an important means of dispersal and gene flow, however, the movement of animals has led to the spread of various diseases globally and wildlife are often the reservoirs of these diseases. Currently, Cape Mountain Zebra are translocated within South Africa as a management method for augmentation of isolated and fragmented populations. The movement of pathogens due to translocations in local regions have gone largely unchecked, particularly where there may still be isolated regions that can be negatively affected. Equine piroplasmosis is a tick-borne disease caused by Theilaria equi and/or Babesia caballi reported to occur in equids (Bhoora et al., 2010; Zweygarth et al., 2002). Here, the presence of T. equi and B. caballi was detected in 137 clinically healthy Cape Mountain Zebra from three South African reserves, Mountain Zebra National Park (MZNP), De Hoop Nature Reserve (DHNR) and Karoo National Park (KNP) using the multiplex EP real-time PCR (qPCR) assay. We observed 100% prevalence for T. equi and identified only one animal from MZNP with B. caballi. These results affirm that precautions should be taken prior to founding new populations of Cape Mountain Zebra and that potential farms and properties adjacent to prospective reserves should be screened for the presence of the organisms in order to mitigate risks of infection to domestic animals.
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Hiding in Plain Sight: Evidence of Hybridization between Cape Mountain Zebra (Equus Zebra Zebra) and Plains Zebra (Equus quagga burchelli)
African Journal of Wildlife Research, 2017Co-Authors: Desiré L. Dalton, David Zimmermann, Clearance Mnisi, Megan Taplin, Peter Novellie, Halzska Hrabar, Antoinette KotzeAbstract:Historically, Cape Mountain Zebras (Equus Zebra Zebra) were widely distributed along Mountain ranges in the Eastern and Western Cape provinces of South Africa (Boshoff, Landman & Kerley, 2015). By the 1930s, excessive hunting and habitat loss resulted in a reduction in Cape Mountain Zebra numbers with populations being confined to only five localities. Two of these subpopulations subsequently became extinct. Three relic populations currently exist; the population in the Cradock district,was formally protected in 1937 by the proclamation of the Mountain Zebra National Park (MZNP; Lloyd 1984). The two other populations in the Kammanassie and Gamka Mountains, have been protected since 1923 and 1971, respectively. Cape Mountain Zebra numbers increased steadily from their critical status of fewer than 80 individuals in the 1950s, to an estimated minimum of 4791 individuals by 2015 (Hrabar & Kerley, 2015). Plains Zebra (Equus quagga burchelli) were subsequently introduced, in sympatry with Cape Mountain Zebra into four formally protected areas, including the MZNP in 1999 and Karoo National Park in 1998. Until recently no cases of hybridization between plains Zebra and Cape Mountain Zebra were known. Hybridization was not of great concern as a threat to Cape Mountain Zebra populations as fertile hybrids were thought to be unlikely, due to the relatively large difference in the number of chromosomal pairs between the two species (44 versus 32 in plains Zebra and Cape Mountain Zebra, respectively; Ryder, Epel & Benirschke, 1978; Cordingley et al., 2009; Hrabar & Kerley, 2013). By 2013, the plains Zebra population had increased substantially in the MZNP (estimated at 769 Cape Mountain Zebra and 124 plains Zebra by aerial census (unpublished aerial census data, 2013) and were potentially competing with Cape Mountain Zebra for resources. A decision was thus taken to remove the plains Zebra. This intervention resulted in a disruption in the social structure, and some of the small, fragmented groups or plains Zebra individuals joined Cape Mountain Zebra herds. In addition, conservation officials observed ‘Cape Mountain Zebra’ with plains Zebra characteristics. These included slight shadow striping, stripes extending all the way down to the ventral midline of the chest and abdomen, and, although they did have the reddish muzzle of Mountain Zebra, they did not have the characteristic Mountain Zebra gridiron pattern on their rumps (Fig. 1), but rather had absent or distorted patterns on the rump. They exhibited the distinct dewlap of the Cape Mountain Zebra and ear shapes were similar to plains Zebra. This raised concerns of possible hybridization between the two species. Here, we report on a molecular evaluation using maternal, paternal and biparental markers to identify suspected hybrid Cape Mountain and plains Zebra in MZNP and Karoo National Park, South Africa.
Russell A Hill - One of the best experts on this subject based on the ideXlab platform.
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Resolving management conflicts : could agricultural land provide the answer for an endangered species in a habitat classified as a World Heritage Site ?
Environmental Conservation, 2011Co-Authors: Rebecca K Smith, Emma Ryan, Emma Morley, Russell A HillAbstract:SUMMARY The short-interval fires required to promote grazing for large herbivores within the Cape Floristic Region World Heritage Site are detrimental to plant diversity. At the same time, longer interval fires significantly reduce graze quality. Conservation managers thus face an enormous challenge when the herbivores are also a conservation priority, since the competing conservation objectives are difficult to reconcile. Population growth rates of genetically important populations of endangered Cape Mountain Zebra (Equus Zebra Zebra) are low or declining following management focused on their fynbos habitat. Investigation of spatial and temporal habitat use and the diet of Cape Mountain Zebra, focusing on the use of land historically converted to agricultural grassland within fynbos in De Hoop Nature Reserve (South Africa), determined factors limiting populations and facilitated development of management strategies. Zebras selected grassland over other habitat types, despite grassland accounting for only a small proportion of the reserve. Grasses also made up the greatest proportion of diet for Zebras throughout the year. Time spent on grasslands increased with grass height and was likely to have been influenced by grass protein levels. It is likely that grazing resourcesarealimiting factorforZebra,andsooptions for improving and/or increasing grassland at De Hoop should be considered. Translocation of surplus males to other conservation areas, reductions in other herbivore populations and targeted burns to increase grassland availability all offer short-term solutions. However, the acquisition of agricultural grassland adjacent to reserves is likely to be a viable long-term management strategy for this and other genetically important Cape Mountain Zebra populations. Low conservation priority habitats, such as farmland, should be considered for other management conflicts, as they have the potential to play a vital role in conservation.
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Is isolation the major genetic concern for endangered equids
Animal Conservation, 2009Co-Authors: Russell A HillAbstract:Although hybridization between closely related species is a natural phenomenon that can operate as an important evolutionary force, it has nevertheless contributed to the extinction of numerous species. Where the causes of hybridization are largely anthropogenic, therefore, its consequences need to be carefully assessed. Such investigations become pressing when one or both of the species concerned are endangered, since some form of management intervention may be required to limit the hybridization. Nevertheless, observations of hybridization involving species of conservation concern do not in themselves necessitate management action. Cordingley et al. (2009) report the first case of natural hybridization between two equid species; the abundant plains Zebra Equus burchelli and the endangered Grevy’s Zebra Equus grevyi. Since global numbers of Grevy’s Zebra have declined dramatically in recent decades due to human activity, hybridization could represent a significant further risk to the conservation of the species. Fortunately, as Cordingley et al. (2009) outline, hybridization does not appear to constitute a serious threat to Grevy’s Zebra because hybrids seemingly integrate into plains Zebra society. Thus while the hybrids are reproductive, there appears to be little possibility of backcrossing due to behavioural isolation and gene flow is essentially unidirectional from the Grevy’s Zebra to the plains Zebra population. As long as these conditions persist there is little immediate threat to the Grevy’s Zebra population from hybridization with plains Zebra. These results are important since they suggest that conservation resources would be wasted on trying to control the hybridization and management efforts would be better directed at other, more immediate threats to Grevy’s Zebra populations. The one caveat to this, however, relates to the anomalous result of two Grevy’s Zebra females having plains Zebra mtDNA haplotypes. While Cordingley et al. (2009) attribute this to an error in sample collection, there is an urgent need for further genetic sampling to ensure that the current findings are robust and substantiated in a broader sample. Without such confirmation it may be premature to conclude that hybridization is of little risk to the Grevy’s Zebra gene pool. In essence, it would be difficult to categorically direct management efforts away from the issue of hybridization when there is any uncertainty over the scientific basis of this decision. Errors made now may not easily be undone in future years. Nevertheless if, as seems likely, the conclusions of Cordingley et al. (2009) are confirmed with further sampling, the current study does suggest that the Grevy’s Zebra gene pool may still be at risk even if hybridization is not the major threat. The Grevy’s Zebra within the Ol Pejeta population appear isolated from other neighbouring populations, and the main anthropogenic threats to the species suggest that the meta-population could become increasingly fragmented in isolated populations. Lessons from another endangered African equid, the Cape Mountain Zebra Equus Zebra Zebra indicate that this can have disastrous genetic consequences. Hunting and habitat destruction over the past three centuries decimated the world population of Cape Mountain Zebra to fewer than 100 individuals in five relict populations, and while sustained conservation efforts have elevated this number to more than 1600 animals, over 90% of the stock has derived from a single source population (Moodley & Harley, 2005). The result is low genetic variation within individual Cape Mountain Zebra populations, the characteristic signature of population fragmentation and drift. Moderate variation does still exist across the entire Cape Mountain Zebra meta-population suggesting that a management strategy focused on the mixing of the original relict populations could halt further loss of genetic diversity (Moodley & Harley, 2005). Such a strategy is far from straightforward, however, and active management is required to sustain population growth in critical populations (Watson et al., 2005; Smith et al., 2008). While the situation is far from this serious in Grevy’s Zebra, evidence from the other Mountain Zebra subspecies,
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monitoring and management of the endangered cape Mountain Zebra equus Zebra Zebra in the western cape south africa
African Journal of Ecology, 2008Co-Authors: Peter Chadwick, Rebecca K Smith, Andrae Marais, Peter Lloyd, Russell A HillAbstract:De Hoop Nature Reserve and a neighbouring conservancy contain the most genetically diverse subpopulation of the Endangered (IUCN) Cape Mountain Zebra (Equus Zebra Zebra Linnaeus 1758). Although vital for the long-term stability of the meta-population, the population had received limited monitoring post-1999. We summarize data obtained during a population monitoring programme established in 2005. Ninety-nine individuals were identified indicating a decline in annual population growth from 6.6% (1995‐1999) to 4.5% (1999‐2005). The population was male biased and the deficit of females is likely to have prevented additional breeding herd formation resulting in excess nonbreeding males. These animals are currently of limited reproductive value to the meta-population and may be contributing to the decline in reproductive potential at De Hoop by competing for limited resources. One solution may be to translocate ‘excess’ males to reinforce existing small populations or establish new populations with females from elsewhere provided that a minimum of 78 animals is maintained at De Hoop to limit genetic loss. Population monitoring and effective management strategies for the De Hoop population and the meta-population are vital to ensure the long-term survival of Cape Mountain Zebra and for the success of other species recovery
Yoshan Moodley - One of the best experts on this subject based on the ideXlab platform.
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Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape Mountain Zebra (Equus Zebra Zebra)
PloS one, 2019Co-Authors: Antoinette Kotze, Yoshan Moodley, Rae Marvin Smith, Gordon Luikart, Coral Birss, Anna M. Van Wyk, J. Paul Grobler, Desiré L. DaltonAbstract:The Cape Mountain Zebra (Equus Zebra Zebra) is a subspecies of Mountain Zebra endemic to South Africa. The Cape Mountain Zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape Mountain Zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape Mountain Zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape Mountain Zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape Mountain Zebra, especially in the face of habitat and climate change and emerging diseases.
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Comparative genetics of sarcoid tumour-affected and non-affected Mountain Zebra (Equus Zebra) populations : research article
South African Journal of Wildlife Research - 24-month delayed open access, 2011Co-Authors: S P Sasidharan, Henk J. Bertschinger, Anette Ludwig, Cindy Kim Harper, Alan John Guthrie, Yoshan MoodleyAbstract:In recent years, South African conservation officials have noted the appearance of sarcoid tumour-like growths in Cape Mountain Zebra (Equus Zebra Zebra) populations. In domestic horses (Equus ferus caballus), a genetic predisposition for this bovine papillomavirus-induced tumour is reported. This investigation compared population genetic parameters within tumour-affected populations in Bontebok National Park and Gariep Dam Nature Reserve against Cape Mountain Zebra populations having few or no tumours in Karoo National Park and Karoo Nature Reserve in South Africa and Hartmann's Mountain Zebra populations from Namibia. Tumour-affected populations had the lowest levels of expected heterozygosity, gene diversity and polymorphism and highest values of internal relatedness and homozygosity by loci but not reaching levels of significance (P = 0.05). Wright's FIS values indicated an overall deficit of heterozygotes in both affected and non-affected Cape Mountain Zebra populations. Considerable population substructuring, as indicated by FST values and Bayesian clustering, was revealed among all Cape Mountain Zebra populations. The results provide support for current conservation policies aimed at increasing levels of genetic diversity in isolated Cape Mountain Zebra populations.
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Comparative Genetics of Sarcoid Tumour-Affected and Non-Affected Mountain Zebra (Equus Zebra) Populations
South African Journal of Wildlife Research, 2011Co-Authors: S P Sasidharan, Henk J. Bertschinger, Yoshan Moodley, Anette Ludwig, Cindy Kim Harper, Alan John GuthrieAbstract:In recent years, South African conservation officials have noted the appearance of sarcoid tumour-like growths in Cape Mountain Zebra (Equus Zebra Zebra) populations. In domestic horses (Equus ferus caballus), a genetic predisposition for this bovine papillomavirusinduced tumour is reported. This investigation compared population genetic parameters within tumour-affected populations in Bontebok National Park and Gariep Dam Nature Reserve against Cape Mountain Zebra populations having few or no tumours in Karoo National Park and Karoo Nature Reserve in South Africa and Hartmann's Mountain Zebra populations from Namibia. Tumour-affected populations had the lowest levels of expected heterozygosity, gene diversity and polymorphism and highest values of internal relatedness and homozygosity by loci but not reaching levels of significance (P = 0.05). Wright's FIS values indicated an overall deficit of heterozygotes in both affected and non-affected Cape Mountain Zebra populations. Considerable population substr...
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Population structuring in Mountain Zebras (Equus Zebra): The molecular consequences of divergent demographic histories
Conservation Genetics, 2005Co-Authors: Yoshan Moodley, Eric H. HarleyAbstract:The endangered Mountain Zebra ( Equus Zebra ) is endemic to the semi-arid inhospitable Mountainous escarpments of southern Africa. The species is divided taxonomically into two geographically separated subspecies, each with differing recent population histories. In Namibia, Hartmann’s Mountain Zebra ( E. z. hartmannae ) is common and occurs in large free-ranging populations, whereas in South Africa, prolonged hunting and habitat destruction over the last 300 years has decimated populations of the Cape Mountain Zebra ( E. z. Zebra ). In this study, we investigate the consequences of these divergent demographic histories for population genetic diversity and structure. We also examine the phylogeographic relationship between the two taxonomic groups. Genetic information was obtained at 15 microsatellite loci for 291 individuals from a total of 10 populations as well as 445 bp of the mitochondrial control region sequence data from 77 individuals. Both model-based and standard analytical approaches were used to examine the data. Both types of marker returned levels of diversity and structure that were consistent with population history. Low genetic variation within individual Cape Mountain Zebra populations, the characteristic indicator of population fragmentation and drift, was offset by moderate variation in the entire E. z. Zebra sample. This implies that higher levels of diversity still exist within the Cape Mountain Zebra gene pool. A management strategy that entailed the mixing of aboriginal populations is therefore advocated in order to halt the further loss of Cape Mountain Zebra genetic diversity. Allele frequencies in Hartmann’s Mountain Zebra were relatively resilient to demographic fluctuations. Due to the high incidence of mitochondrial haplotype sharing between populations, the hypothesis that Cape and Hartmann’s Mountain Zebra mitochondrial lineages were reciprocally monophyletic was not supported. However, the presence of private alleles at nuclear loci rendered the two subspecies genetically distinct evolutionary significant units.
Rae Marvin Smith - One of the best experts on this subject based on the ideXlab platform.
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Molecular characterization in the toll-like receptor 9 gene of Cape Mountain Zebra (Equus Zebra Zebra) from three populations.
Infection genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases, 2019Co-Authors: Rae Marvin Smith, Antoinette Kotze, J. Paul Grobler, Desiré L. DaltonAbstract:Toll-like receptors (TLR) are a family of proteins that signal activation of the innate immune response through the recognition of a variety of pathogen molecular compounds. Here, we characterized the complete TLR9 gene in Cape Mountain Zebra (Equus Zebra Zebra) from three populations in South Africa and compared sequences to a variety of horse and donkey breeds. Overall, we identified six single nucleotide polymorpHisms (SNPs). A single SNP (G586S) was non-synonymous, whereas the remaining SNPs were synonymous. The G586S alteration was detected in Cape Mountain Zebra populations with varying frequency. In addition, adaptive diversity was found to be discordant with variation based on neutral markers. The mutation is unique to the Cape Mountain Zebra when compared to other equid species. The structure of TLR9 is relatively conserved and the resulting amino acid substitution was found to have minimal interaction with active sites in the protein. Future studies can explore the effects of this potentially functional mutation which will contribute to our understanding of genetic diversity within adaptive sites of the Cape Mountain Zebra genome.
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Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape Mountain Zebra (Equus Zebra Zebra)
PloS one, 2019Co-Authors: Antoinette Kotze, Yoshan Moodley, Rae Marvin Smith, Gordon Luikart, Coral Birss, Anna M. Van Wyk, J. Paul Grobler, Desiré L. DaltonAbstract:The Cape Mountain Zebra (Equus Zebra Zebra) is a subspecies of Mountain Zebra endemic to South Africa. The Cape Mountain Zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape Mountain Zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape Mountain Zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape Mountain Zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape Mountain Zebra, especially in the face of habitat and climate change and emerging diseases.
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Translocation a potential corridor for equine piroplasms in Cape Mountain Zebra (Equus Zebra Zebra).
International journal for parasitology. Parasites and wildlife, 2019Co-Authors: Rae Marvin Smith, Antoinette Kotze, J. Paul Grobler, Raksha Bhoora, Desiré L. DaltonAbstract:Translocation of animals in fragmented habitats is an important means of dispersal and gene flow, however, the movement of animals has led to the spread of various diseases globally and wildlife are often the reservoirs of these diseases. Currently, Cape Mountain Zebra are translocated within South Africa as a management method for augmentation of isolated and fragmented populations. The movement of pathogens due to translocations in local regions have gone largely unchecked, particularly where there may still be isolated regions that can be negatively affected. Equine piroplasmosis is a tick-borne disease caused by Theilaria equi and/or Babesia caballi reported to occur in equids (Bhoora et al., 2010; Zweygarth et al., 2002). Here, the presence of T. equi and B. caballi was detected in 137 clinically healthy Cape Mountain Zebra from three South African reserves, Mountain Zebra National Park (MZNP), De Hoop Nature Reserve (DHNR) and Karoo National Park (KNP) using the multiplex EP real-time PCR (qPCR) assay. We observed 100% prevalence for T. equi and identified only one animal from MZNP with B. caballi. These results affirm that precautions should be taken prior to founding new populations of Cape Mountain Zebra and that potential farms and properties adjacent to prospective reserves should be screened for the presence of the organisms in order to mitigate risks of infection to domestic animals.