The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
John A. Byers - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding depression in pronghorn (Antilocapra Americana) fawns
Molecular ecology, 2011Co-Authors: Stacey J. Dunn, Lisette P Waits, Erin Clancey, John A. ByersAbstract:Although inbreeding depression affects survival, fitness and population viability, the extent of inbreeding depression in wild populations remains unclear. We examined inbreeding depression in the small, isolated National Bison Range (NBR), MT, pronghorn (Antilocapra Americana) population following a bottleneck. We have studied the National Bison Range pronghorn extensively since 1981, and we have detailed birth, survival and mate choice data. We genotyped all animals in the population between 1999 and 2010 at 19 microsatellite loci, assigned paternities to all fawns based on genotype and constructed a genetic-based pedigree to calculate inbreeding coefficients (f). We found an increase in the frequency of inbreeding following the bottleneck. We detected evidence of inbreeding depression on fawn survival to weaning, birth mass, foot length and condition. We estimated the number of diploid lethal equivalents on survival to weaning as 24.17-28.72. Standardized heterozygosity (H) had a relatively small influence on survival, mass, length and condition compared with f, and H was not correlated with f. We conclude that for pronghorn, H was not a good predictor of pedigree-estimates of f.
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determinants of survival and fecundity through a population bottleneck in pronghorn Antilocapra Americana
Journal of Mammalogy, 2008Co-Authors: Stacey J. Dunn, John A. ByersAbstract:The long-term viability of small, isolated populations has been questioned in light of stochasticity and bottlenecks. Following a drought in northwestern Montana in 2003, the pronghorn (Antilocapra Americana )o f the National Bison Range experienced a demographic bottleneck. We used information theoretic approaches to examine the influence of sex, age, genetic variation, summer lactation, mate-search effort by females, and mating effort by males on subsequent winter survival and spring fecundity. Survival of males was influenced by age, whereas survival of females was influenced by prior energy expenditure and genetic variation, implicating inbreeding depression as the mechanism. Fecundity of females also was influenced by prior energy expenditure and genetic variation, with heterosis as the apparent mechanism. Our results agree with those of other studies that have emphasized the need to maintain genetic variation and limit inbreeding in small, isolated populations, and to account for stochasticity in population viability assessments and long-term management planning.
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microsatellite analysis reveals multiple paternity in a population of wild pronghorn antelopes Antilocapra Americana
Journal of Mammalogy, 2003Co-Authors: Matthew D Carling, Patryce Avsharian Wiseman, John A. ByersAbstract:Although multiple paternity has been observed in various groups of mammals with litter sizes >1, it has not been documented in wild ungulate populations. With the use of DNA microsatellites, we investigated multiple paternity in pronghorn (Antilocapra Americana) at the National Bison Range. Females in this population twin every year, and we were able to assign paternity to 25 sets of twins sired in 1999 and 2000, eleven (44%) of which were fathered by different males. Complex female mate choice is the most likely explanation for the observed pattern; however, sperm competition might contribute if a female has mated multiple times. This study represents the 1st reported example of multiple paternity in a natural ungulate population and indicates that some aspects of mammalian mating systems still are not fully understood.
Alexander S. Graphodatsky - One of the best experts on this subject based on the ideXlab platform.
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comparative chromosome painting of pronghorn Antilocapra Americana and saola pseudoryx nghetinhensis karyotypes with human and dromedary camel probes
BMC Genetics, 2014Co-Authors: Anastasia I. Kulemzina, Polina L Perelman, Darya A Grafodatskaya, Trung T Nguyen, Mary Thompson, Melody E Roelkeparker, Alexander S. GraphodatskyAbstract:Pronghorn (Antilocapridae, 2n = 58) and saola (Bovidae, 2n = 50) are members of Pecora, a highly diversified group of even-toed hoofed mammals. Karyotypes of these species were not involved in chromosome painting studies despite their intriguing phylogenetic positions in Pecora. To trace the chromosome evolution during very fast radiation of main families from the common Pecoran ancestor, high-resolution comparative chromosome maps of pronghorn and saola with human (HSA) and dromedary camel (CDR) painting probes were established. The human and dromedary camel painting probes revealed 50 and 64 conserved segments respectively in the pronghorn genome, while 51 and 63 conserved segments respectively in the saola genome. Integrative analysis with published comparative maps showed that inversions in chromosomes homologous to CDR19/35/19 (HSA 10/20/10), CDR12/34/12 (HSA12/22/12/22), CDR10/33/10 (HSA 11) are present in representatives of all five living Pecoran families. The pronghorn karyotype could have formed from a putative 2n = 58 Pecoran ancestral karyotype by one fission and one fusion and that the saola karyotype differs from the presumed 2n = 60 bovid ancestral karyotype (2n = 60) by five fusions. The establishment of high-resolution comparative maps for pronghorn and saola has shed some new insights into the putative ancestral karyotype, chromosomal evolution and phylogenic relationships in Pecora. No cytogenetic signature rearrangements were found that could unite the Antilocapridae with Giraffidae or with any other Pecoran families. Our data on the saola support a separate position of Pseudorigyna subtribe rather than its affinity to either Bovina or Bubalina, but the saola phylogenetic position within Bovidae remains unresolved.
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Molecular cytogenetic insights to the phylogenetic affinities of the giraffe (Giraffa camelopardalis) and pronghorn (Antilocapra Americana)
Chromosome Research, 2013Co-Authors: Olga Kopecna, Terence J Robinson, Anastasia I. Kulemzina, Polina L Perelman, Frederick F.b. Elder, Alexander S. GraphodatskyAbstract:Five families are traditionally recognized within higher ruminants (Pecora): Bovidae, Moschidae, Cervidae, Giraffidae and Antilocapridae. The phylogenetic relationships of Antilocapridae and Giraffidae within Pecora are, however, uncertain. While numerous fusions (mostly Robertsonian) have accumulated in the giraffe’s karyotype ( Giraffa camelopardalis , Giraffidae, 2 n = 30), that of the pronghorn ( Antilocapra Americana , Antilocapridae, 2 n = 58) is very similar to the hypothesised pecoran ancestral state (2 n = 58). We examined the chromosomal rearrangements of two species, the giraffe and pronghorn, using a combination of fluorescence in situ hybridization painting probes and BAC clones derived from cattle ( Bos taurus , Bovidae). Our data place Moschus (Moschidae) closer to Bovidae than Cervidae. Although the alternative (i.e., Moschidae + Cervidae as sister groups) could not be discounted in recent sequence-based analyses, cytogenetics bolsters conclusions that the former is more likely. Additionally, DNA sequences were isolated from the centromeric regions of both species and compared. Analysis of cenDNA show that unlike the pronghorn, the centromeres of the giraffe are probably organized in a more complex fashion comprising different repetitive sequences specific to single chromosomal pairs or groups of chromosomes. The distribution of nucleolar organiser region (NOR) sites, often an effective phylogenetic marker, were also examined in the two species. In the giraffe, the position of NORs seems to be autapomorphic since similar localizations have not been found in other species within Pecora.
Lisette P Waits - One of the best experts on this subject based on the ideXlab platform.
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examining the use of fecal pellet morphometry to differentiate age classes in sonoran pronghorn
Wildlife Biology, 2016Co-Authors: Susannah P Woodruff, Timothy R Johnson, Lisette P WaitsAbstract:Wildlife managers require knowledge of population demographics, yet for low-density, wide-ranging species procuring demographic information is challenging. While accurate abundance estimates can be costly and difficult to obtain, recruitment and survival trends can be used as an alternative indicator of a population's trajectory. Physical capture has been the traditional practice for obtaining these demographic parameters, yet capture-related stress can lead to reduced levels of fitness, impaired locomotion, or even mortality for some species. Thus, noninvasive sampling methods may provide an alternative to physical capture. Population monitoring of endangered Sonoran pronghorn Antilocapra Americana sonoriensis is critical for assessing the success of recovery efforts, and monitoring annual survival and recruitment by age class would provide information on the trajectory of population growth. We measured noninvasively collected Sonoran pronghorn fecal pellets collected post-fawning in Arizona, USA and mat...
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rapid species identification of sonoran pronghorn from fecal pellet dna
Wildlife Society Bulletin, 2014Co-Authors: Susannah P Woodruff, Jennifer R Adams, Timothy R Johnson, Lisette P WaitsAbstract:The Sonoran pronghorn (Antilocapra Americana sonoriensis) is a subspecies of pronghorn found exclusively in the Sonoran Desert of Arizona (USA) and Mexico. Sonoran pronghorn persist at low densities and are geographically isolated from other pronghorn populations. Numbers have declined in recent decades, but the population has rebounded from a low of fewer than 50 animals in 2003 to an estimated 159 individuals in 2012; however, little is known about population demographics beyond abundance estimates. We developed a species identification test that uses mitochondrial DNA (mtDNA) species-specific primers to distinguish between sympatric Sonoran pronghorn and mule deer (Odocoileus hemionus) using DNA extracted from fecal pellets. We accurately identified each species in 100% of the blood and tissue reference samples. We also evaluate the rate of DNA degradation in pronghorn fecal samples ranging from 1 day to 124 days old and document that mtDNA species identification success rates were 100% through day 14. Success rates dropped to 95% by day 21, 50% on day 60, and 10% by day 124. This new test will be a valuable tool for documenting the presence of Sonoran pronghorn across their current range and can also be used for other pronghorn populations. © 2014 The Wildlife Society.
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Inbreeding depression in pronghorn (Antilocapra Americana) fawns
Molecular ecology, 2011Co-Authors: Stacey J. Dunn, Lisette P Waits, Erin Clancey, John A. ByersAbstract:Although inbreeding depression affects survival, fitness and population viability, the extent of inbreeding depression in wild populations remains unclear. We examined inbreeding depression in the small, isolated National Bison Range (NBR), MT, pronghorn (Antilocapra Americana) population following a bottleneck. We have studied the National Bison Range pronghorn extensively since 1981, and we have detailed birth, survival and mate choice data. We genotyped all animals in the population between 1999 and 2010 at 19 microsatellite loci, assigned paternities to all fawns based on genotype and constructed a genetic-based pedigree to calculate inbreeding coefficients (f). We found an increase in the frequency of inbreeding following the bottleneck. We detected evidence of inbreeding depression on fawn survival to weaning, birth mass, foot length and condition. We estimated the number of diploid lethal equivalents on survival to weaning as 24.17-28.72. Standardized heterozygosity (H) had a relatively small influence on survival, mass, length and condition compared with f, and H was not correlated with f. We conclude that for pronghorn, H was not a good predictor of pedigree-estimates of f.
Stacey J. Dunn - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding depression in pronghorn (Antilocapra Americana) fawns
Molecular ecology, 2011Co-Authors: Stacey J. Dunn, Lisette P Waits, Erin Clancey, John A. ByersAbstract:Although inbreeding depression affects survival, fitness and population viability, the extent of inbreeding depression in wild populations remains unclear. We examined inbreeding depression in the small, isolated National Bison Range (NBR), MT, pronghorn (Antilocapra Americana) population following a bottleneck. We have studied the National Bison Range pronghorn extensively since 1981, and we have detailed birth, survival and mate choice data. We genotyped all animals in the population between 1999 and 2010 at 19 microsatellite loci, assigned paternities to all fawns based on genotype and constructed a genetic-based pedigree to calculate inbreeding coefficients (f). We found an increase in the frequency of inbreeding following the bottleneck. We detected evidence of inbreeding depression on fawn survival to weaning, birth mass, foot length and condition. We estimated the number of diploid lethal equivalents on survival to weaning as 24.17-28.72. Standardized heterozygosity (H) had a relatively small influence on survival, mass, length and condition compared with f, and H was not correlated with f. We conclude that for pronghorn, H was not a good predictor of pedigree-estimates of f.
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determinants of survival and fecundity through a population bottleneck in pronghorn Antilocapra Americana
Journal of Mammalogy, 2008Co-Authors: Stacey J. Dunn, John A. ByersAbstract:The long-term viability of small, isolated populations has been questioned in light of stochasticity and bottlenecks. Following a drought in northwestern Montana in 2003, the pronghorn (Antilocapra Americana )o f the National Bison Range experienced a demographic bottleneck. We used information theoretic approaches to examine the influence of sex, age, genetic variation, summer lactation, mate-search effort by females, and mating effort by males on subsequent winter survival and spring fecundity. Survival of males was influenced by age, whereas survival of females was influenced by prior energy expenditure and genetic variation, implicating inbreeding depression as the mechanism. Fecundity of females also was influenced by prior energy expenditure and genetic variation, with heterosis as the apparent mechanism. Our results agree with those of other studies that have emphasized the need to maintain genetic variation and limit inbreeding in small, isolated populations, and to account for stochasticity in population viability assessments and long-term management planning.
Polina L Perelman - One of the best experts on this subject based on the ideXlab platform.
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comparative chromosome painting of pronghorn Antilocapra Americana and saola pseudoryx nghetinhensis karyotypes with human and dromedary camel probes
BMC Genetics, 2014Co-Authors: Anastasia I. Kulemzina, Polina L Perelman, Darya A Grafodatskaya, Trung T Nguyen, Mary Thompson, Melody E Roelkeparker, Alexander S. GraphodatskyAbstract:Pronghorn (Antilocapridae, 2n = 58) and saola (Bovidae, 2n = 50) are members of Pecora, a highly diversified group of even-toed hoofed mammals. Karyotypes of these species were not involved in chromosome painting studies despite their intriguing phylogenetic positions in Pecora. To trace the chromosome evolution during very fast radiation of main families from the common Pecoran ancestor, high-resolution comparative chromosome maps of pronghorn and saola with human (HSA) and dromedary camel (CDR) painting probes were established. The human and dromedary camel painting probes revealed 50 and 64 conserved segments respectively in the pronghorn genome, while 51 and 63 conserved segments respectively in the saola genome. Integrative analysis with published comparative maps showed that inversions in chromosomes homologous to CDR19/35/19 (HSA 10/20/10), CDR12/34/12 (HSA12/22/12/22), CDR10/33/10 (HSA 11) are present in representatives of all five living Pecoran families. The pronghorn karyotype could have formed from a putative 2n = 58 Pecoran ancestral karyotype by one fission and one fusion and that the saola karyotype differs from the presumed 2n = 60 bovid ancestral karyotype (2n = 60) by five fusions. The establishment of high-resolution comparative maps for pronghorn and saola has shed some new insights into the putative ancestral karyotype, chromosomal evolution and phylogenic relationships in Pecora. No cytogenetic signature rearrangements were found that could unite the Antilocapridae with Giraffidae or with any other Pecoran families. Our data on the saola support a separate position of Pseudorigyna subtribe rather than its affinity to either Bovina or Bubalina, but the saola phylogenetic position within Bovidae remains unresolved.
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Molecular cytogenetic insights to the phylogenetic affinities of the giraffe (Giraffa camelopardalis) and pronghorn (Antilocapra Americana)
Chromosome Research, 2013Co-Authors: Olga Kopecna, Terence J Robinson, Anastasia I. Kulemzina, Polina L Perelman, Frederick F.b. Elder, Alexander S. GraphodatskyAbstract:Five families are traditionally recognized within higher ruminants (Pecora): Bovidae, Moschidae, Cervidae, Giraffidae and Antilocapridae. The phylogenetic relationships of Antilocapridae and Giraffidae within Pecora are, however, uncertain. While numerous fusions (mostly Robertsonian) have accumulated in the giraffe’s karyotype ( Giraffa camelopardalis , Giraffidae, 2 n = 30), that of the pronghorn ( Antilocapra Americana , Antilocapridae, 2 n = 58) is very similar to the hypothesised pecoran ancestral state (2 n = 58). We examined the chromosomal rearrangements of two species, the giraffe and pronghorn, using a combination of fluorescence in situ hybridization painting probes and BAC clones derived from cattle ( Bos taurus , Bovidae). Our data place Moschus (Moschidae) closer to Bovidae than Cervidae. Although the alternative (i.e., Moschidae + Cervidae as sister groups) could not be discounted in recent sequence-based analyses, cytogenetics bolsters conclusions that the former is more likely. Additionally, DNA sequences were isolated from the centromeric regions of both species and compared. Analysis of cenDNA show that unlike the pronghorn, the centromeres of the giraffe are probably organized in a more complex fashion comprising different repetitive sequences specific to single chromosomal pairs or groups of chromosomes. The distribution of nucleolar organiser region (NOR) sites, often an effective phylogenetic marker, were also examined in the two species. In the giraffe, the position of NORs seems to be autapomorphic since similar localizations have not been found in other species within Pecora.