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Matthew C. Allender - One of the best experts on this subject based on the ideXlab platform.
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blood lactate concentrations in eastern box turtles Terrapene carolina carolina following capture by a canine search team
Journal of Zoo and Wildlife Medicine, 2021Co-Authors: Katy Klein, Laura Adamovicz, Christopher A Phillips, Matthew C. AllenderAbstract:Studies to assess wildlife health commonly evaluate clinical pathology changes, immune responses, pathogen presence, and contaminant exposure, but novel modalities are needed to characterize the unique physiologic responses of reptiles. Lactate is an indicator of hypoperfusion and/or anaerobic respiration and can be quickly and easily measured using a point-of-care analyzer. This study evaluated baseline blood lactate concentrations in free-living eastern box turtles (Terrapene carolina carolina, n = 116) using a point of care analyzer and then determined the effect of handling time, physical examination (PE) abnormalities, and quantitative polymerase chain reaction pathogen detection (Terrapene herpesvirus 1, Mycoplasma sp., Terrapene adenovirus) on lactate concentrations. Blood lactate concentrations were higher in turtles with Terrapene herpesvirus 1 (n = 11), quiet mentation, and increased packed cell volume (P < 0.05). Lactate concentrations increased between initial capture and PE, with peak values reaching 129 min after capture. Lactate at PE was positively associated with baseline lactate concentrations. Turtles with Terrapene herpesvirus 1 may have alterations in blood flow, oxygen delivery, or activity patterns, driving increases in baseline lactate. Increased handling time likely leads to more escape behaviors and/or breath holding, causing turtles to undergo anaerobic metabolism and raising lactate concentrations. Overall, lactate measured by a point of care analyzer shows variability caused by capture and health factors in eastern box turtles and may be a useful adjunctive diagnostic test in this species after full methodologic validation.
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Plasma complement activation mechanisms differ in ornate (Terrapene ornata ornata) and eastern box turtles (Terrapene carolina carolina)
Journal of experimental zoology. Part A Ecological and integrative physiology, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Mark Merchant, Lancia N.f. Darville, Matthew C. AllenderAbstract:Eastern (Terrapene carolina carolina) and ornate (Terrapene ornata ornata) box turtles have robust plasma antibacterial activity, however, the mechanism behind this activity is unknown. We used sheep red blood cell (SRBC) hemolysis assays, mannan-affinity chromatography, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) to explore the mechanisms of complement activity in box turtles. Plasma from both species demonstrated volume, time, and temperature-dependent SRBC hemolysis, with significantly greater hemolytic activity in ornate box turtle plasma. Hemolytic activity was highly attenuated following treatment with heat, EDTA, and salicylaldoxime in both species, but was unchanged after treatment with methylamine and ammonium hydroxide. Two abundant mannan-binding proteins (presumed C-type lectins) were identified in eastern box turtle plasma using SDS-PAGE and MALDI-TOF, but ornate box turtles did not express either protein. Eastern box turtles appear to rely on the lectin pathway of complement activation while ornate box turtles utilize the alternative pathway. This study provides further evidence that mechanisms underlying immune function are not always conserved between closely related species. This finding may have important implications for explaining species differences in susceptibility to emerging threats such as disease, toxicants, and climate change.
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Development and validation of a quantitative PCR assay for detection of Terrapene herpesvirus 2 in eastern box turtles (Terrapene carolina carolina).
Journal of virological methods, 2020Co-Authors: Aubrey I. Engel, Laura Adamovicz, James F. X. Wellehan, Matthew C. AllenderAbstract:Abstract Herpesviruses are associated with disease in many chelonian species, resulting in pathology such as respiratory tract infection, stomatitis, conjunctivitis, hepatitis, and papillomatosis. Herpesvirus-associated fibropapillomas cause significant morbidity and mortality in marine turtles, and have been identified in an eastern box turtle (Terrapene carolina carolina) infected with Terrapene herpesvirus 2 (TerHV2). Further investigation is necessary to understand the impact of carcinogenic herpesviruses on chelonian health; however, reliable and specific methods for detection and quantitation of herpesviral load are lacking. The purpose of this study was to develop and validate a quantitative PCR assay for detection of TerHV2 in box turtles. TaqMan primer-probes were developed targeting the DNA polymerase gene. Inter- and intra-assay variability, linear range of detection, limit of detection, and specificity were assessed. The assay was highly specific for TerHV2, failing to amplify seven closely-related chelonian herpesviruses. It performed with high efficiency (slope = -3.52, R2 = 1, efficiency = 92.29 %), low intra-assay variability and low inter-assay variability (coefficient of variation ≤ 1.25 % at all standard dilutions). Reaction efficiency was not impacted in the presence of box turtle DNA from combined oral/cloacal swabs or whole blood. This qPCR assay has a linear range of detection from 107 to 101 viral copies per reaction and provides a valuable tool in the surveillance and characterization of TerHV2 in box turtles.
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erythrocyte sedimentation rate and hemoglobin binding protein in free living box turtles Terrapene spp
PLOS ONE, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Ethan J Kessler, Marta Kelly, Samantha Johnson, John M Winter, Christopher A Phillips, Matthew C. AllenderAbstract:The acute phase response is a highly conserved reaction to infection, inflammation, trauma, stress, and neoplasia. Acute phase assays are useful for wildlife health assessment, however, they are infrequently utilized in reptiles. This study evaluated erythrocyte sedimentation rate (ESR) in eastern (Terrapene carolina carolina) and ornate box turtles (Terrapene ornata ornata) and hemoglobin-binding protein (HBP) in T. ornata. Erythrocyte sedimentation rate in 90 T. carolina and 105 T. ornata was negatively associated with packed cell volume and was greater in unhealthy turtles (p < 0.05). Female T. ornata had higher ESR values than males (p < 0.05). Measurement of ESR with a microhematocrit tube proportionally overestimated values from a commercial kit (Winpette), though both methods may retain utility with separate reference intervals. Hemoglobin-binding protein concentration in 184 T. ornata was significantly increased in adults and unhealthy turtles (p < 0.05). Erythrocyte sedimentation rate values were similar between seasons and populations, and HBP values were consistent between years, indicating that these analytes may have more stable baseline values than traditional health metrics in reptiles. This study demonstrates that ESR and HBP are promising diagnostics for health assessment in wild box turtles. Incorporating these tests into wild herptile health assessment protocols may support conservation efforts and improve ecosystem health monitoring.
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Plasma antibacterial activities in ornate (Terrapene ornata) and eastern box turtles (Terrapene carolina)
Journal of experimental zoology. Part A Ecological and integrative physiology, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Mark Merchant, Matthew C. AllenderAbstract:Chelonians are one of the most imperiled vertebrate taxa and many species are increasingly threatened by disease, however, the immune response in this group is understudied. We quantified the innate immune response of eastern (Terrapene carolina; EBT) and ornate (Terrapene ornate; OBT) box turtles using plasma antibacterial activity assays. Plasma from both species abolished or significantly reduced the growth of all eight bacterial species evaluated, including Salmonella typhimurium, Escherichia coli, Enterobacter cloacae, Citrobacter freundi, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. Bactericidal capacity was greater in OBT compared to EBT, and OBT plasma retained high antibacterial activities at a broader temperature range (20-40°C) compared to EBT (30-40°C). Plasma antibacterial activity was abolished following treatment with heat, protease, and ethylenediaminetetraacetic acid, indicating that complement is likely responsible for the observed effects. Further characterization of the box turtle immune response may provide insight into the importance of infectious diseases for species conservation, enabling the development of more efficient and effective population management strategies.
Laura Adamovicz - One of the best experts on this subject based on the ideXlab platform.
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blood lactate concentrations in eastern box turtles Terrapene carolina carolina following capture by a canine search team
Journal of Zoo and Wildlife Medicine, 2021Co-Authors: Katy Klein, Laura Adamovicz, Christopher A Phillips, Matthew C. AllenderAbstract:Studies to assess wildlife health commonly evaluate clinical pathology changes, immune responses, pathogen presence, and contaminant exposure, but novel modalities are needed to characterize the unique physiologic responses of reptiles. Lactate is an indicator of hypoperfusion and/or anaerobic respiration and can be quickly and easily measured using a point-of-care analyzer. This study evaluated baseline blood lactate concentrations in free-living eastern box turtles (Terrapene carolina carolina, n = 116) using a point of care analyzer and then determined the effect of handling time, physical examination (PE) abnormalities, and quantitative polymerase chain reaction pathogen detection (Terrapene herpesvirus 1, Mycoplasma sp., Terrapene adenovirus) on lactate concentrations. Blood lactate concentrations were higher in turtles with Terrapene herpesvirus 1 (n = 11), quiet mentation, and increased packed cell volume (P < 0.05). Lactate concentrations increased between initial capture and PE, with peak values reaching 129 min after capture. Lactate at PE was positively associated with baseline lactate concentrations. Turtles with Terrapene herpesvirus 1 may have alterations in blood flow, oxygen delivery, or activity patterns, driving increases in baseline lactate. Increased handling time likely leads to more escape behaviors and/or breath holding, causing turtles to undergo anaerobic metabolism and raising lactate concentrations. Overall, lactate measured by a point of care analyzer shows variability caused by capture and health factors in eastern box turtles and may be a useful adjunctive diagnostic test in this species after full methodologic validation.
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Plasma complement activation mechanisms differ in ornate (Terrapene ornata ornata) and eastern box turtles (Terrapene carolina carolina)
Journal of experimental zoology. Part A Ecological and integrative physiology, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Mark Merchant, Lancia N.f. Darville, Matthew C. AllenderAbstract:Eastern (Terrapene carolina carolina) and ornate (Terrapene ornata ornata) box turtles have robust plasma antibacterial activity, however, the mechanism behind this activity is unknown. We used sheep red blood cell (SRBC) hemolysis assays, mannan-affinity chromatography, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) to explore the mechanisms of complement activity in box turtles. Plasma from both species demonstrated volume, time, and temperature-dependent SRBC hemolysis, with significantly greater hemolytic activity in ornate box turtle plasma. Hemolytic activity was highly attenuated following treatment with heat, EDTA, and salicylaldoxime in both species, but was unchanged after treatment with methylamine and ammonium hydroxide. Two abundant mannan-binding proteins (presumed C-type lectins) were identified in eastern box turtle plasma using SDS-PAGE and MALDI-TOF, but ornate box turtles did not express either protein. Eastern box turtles appear to rely on the lectin pathway of complement activation while ornate box turtles utilize the alternative pathway. This study provides further evidence that mechanisms underlying immune function are not always conserved between closely related species. This finding may have important implications for explaining species differences in susceptibility to emerging threats such as disease, toxicants, and climate change.
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Development and validation of a quantitative PCR assay for detection of Terrapene herpesvirus 2 in eastern box turtles (Terrapene carolina carolina).
Journal of virological methods, 2020Co-Authors: Aubrey I. Engel, Laura Adamovicz, James F. X. Wellehan, Matthew C. AllenderAbstract:Abstract Herpesviruses are associated with disease in many chelonian species, resulting in pathology such as respiratory tract infection, stomatitis, conjunctivitis, hepatitis, and papillomatosis. Herpesvirus-associated fibropapillomas cause significant morbidity and mortality in marine turtles, and have been identified in an eastern box turtle (Terrapene carolina carolina) infected with Terrapene herpesvirus 2 (TerHV2). Further investigation is necessary to understand the impact of carcinogenic herpesviruses on chelonian health; however, reliable and specific methods for detection and quantitation of herpesviral load are lacking. The purpose of this study was to develop and validate a quantitative PCR assay for detection of TerHV2 in box turtles. TaqMan primer-probes were developed targeting the DNA polymerase gene. Inter- and intra-assay variability, linear range of detection, limit of detection, and specificity were assessed. The assay was highly specific for TerHV2, failing to amplify seven closely-related chelonian herpesviruses. It performed with high efficiency (slope = -3.52, R2 = 1, efficiency = 92.29 %), low intra-assay variability and low inter-assay variability (coefficient of variation ≤ 1.25 % at all standard dilutions). Reaction efficiency was not impacted in the presence of box turtle DNA from combined oral/cloacal swabs or whole blood. This qPCR assay has a linear range of detection from 107 to 101 viral copies per reaction and provides a valuable tool in the surveillance and characterization of TerHV2 in box turtles.
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erythrocyte sedimentation rate and hemoglobin binding protein in free living box turtles Terrapene spp
PLOS ONE, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Ethan J Kessler, Marta Kelly, Samantha Johnson, John M Winter, Christopher A Phillips, Matthew C. AllenderAbstract:The acute phase response is a highly conserved reaction to infection, inflammation, trauma, stress, and neoplasia. Acute phase assays are useful for wildlife health assessment, however, they are infrequently utilized in reptiles. This study evaluated erythrocyte sedimentation rate (ESR) in eastern (Terrapene carolina carolina) and ornate box turtles (Terrapene ornata ornata) and hemoglobin-binding protein (HBP) in T. ornata. Erythrocyte sedimentation rate in 90 T. carolina and 105 T. ornata was negatively associated with packed cell volume and was greater in unhealthy turtles (p < 0.05). Female T. ornata had higher ESR values than males (p < 0.05). Measurement of ESR with a microhematocrit tube proportionally overestimated values from a commercial kit (Winpette), though both methods may retain utility with separate reference intervals. Hemoglobin-binding protein concentration in 184 T. ornata was significantly increased in adults and unhealthy turtles (p < 0.05). Erythrocyte sedimentation rate values were similar between seasons and populations, and HBP values were consistent between years, indicating that these analytes may have more stable baseline values than traditional health metrics in reptiles. This study demonstrates that ESR and HBP are promising diagnostics for health assessment in wild box turtles. Incorporating these tests into wild herptile health assessment protocols may support conservation efforts and improve ecosystem health monitoring.
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Plasma antibacterial activities in ornate (Terrapene ornata) and eastern box turtles (Terrapene carolina)
Journal of experimental zoology. Part A Ecological and integrative physiology, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Mark Merchant, Matthew C. AllenderAbstract:Chelonians are one of the most imperiled vertebrate taxa and many species are increasingly threatened by disease, however, the immune response in this group is understudied. We quantified the innate immune response of eastern (Terrapene carolina; EBT) and ornate (Terrapene ornate; OBT) box turtles using plasma antibacterial activity assays. Plasma from both species abolished or significantly reduced the growth of all eight bacterial species evaluated, including Salmonella typhimurium, Escherichia coli, Enterobacter cloacae, Citrobacter freundi, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. Bactericidal capacity was greater in OBT compared to EBT, and OBT plasma retained high antibacterial activities at a broader temperature range (20-40°C) compared to EBT (30-40°C). Plasma antibacterial activity was abolished following treatment with heat, protease, and ethylenediaminetetraacetic acid, indicating that complement is likely responsible for the observed effects. Further characterization of the box turtle immune response may provide insight into the importance of infectious diseases for species conservation, enabling the development of more efficient and effective population management strategies.
William I. Lutterschmidt - One of the best experts on this subject based on the ideXlab platform.
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effects of urbanization on genetic diversity gene flow and population structure in the ornate box turtle Terrapene ornata
Amphibia-reptilia, 2014Co-Authors: James C Cureton, Christopher P. Randle, William I. Lutterschmidt, Michael W Janis, Donald C Ruthven, Raelynn DeatonAbstract:Large-scale declines in North American box turtle (Terrapene spp.) populations have been attributed to habitat fragmentation as a result of urbanization. We compared microsatellite markers and mitochondrial control region sequences of Ornate Box Turtles (Terrapene ornata) in two populations (a natural and an urban habitat) to test two hypotheses. We hypothesized that urban populations of T. ornata experience genetic bottlenecks due to road mortality and habitat fragmentation, and that roadways represent a barrier to gene flow among turtle populations, resulting in increased fragmentation of gene pools. Both populations shared similar allelic diversity and observed heterozygosity, with eight and seven of twelve microsatellite loci exhibiting heterozygote deficiency in the natural and urban populations, respectively. The number of mitochondrial control region haplotypes in the urban population was nearly four times that of the natural population, although only one haplotype occurred in appreciable frequency in both populations. We did not detect conclusive evidence of a recent genetic bottleneck in the urban population, thereby rejecting our first hypothesis. We detected weak differentiation among populations on opposing sides of a large highway, but did not detect any evidence of population structure, thereby rejecting our second hypothesis. This study indicates that a population of T. ornata with moderate road mortality currently has high genetic diversity, moderate inbreeding, and displays some evidence of genetic differentiation, but no conclusive evidence of recent genetic bottlenecks or unique genetic clustering. We suggest this is primarily due to the species long generation time and is a positive aspect of their life-history.
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Characterization of ten novel microsatellite loci for the threatened Ornate Box Turtle, Terrapene ornata
Conservation Genetics Resources, 2009Co-Authors: James C Cureton, William I. Lutterschmidt, Christopher P. Randle, Anna Buchman, Raelynn DeatonAbstract:Growing evidence suggests that North American Box Turtles (Terrapene spp.) are declining at an increasing rate. However, there is currently a large gap in our general knowledge of box turtles; thus, baseline demographic and genetic data are needed before a conservation plan can be developed for this group. Therefore, we developed ten microsatellite primers specific to Terrapene ornata. Of the 22 primers developed, 10 consistently amplified at least 20 of the 22 individuals tested. We detected no linkage disequilibrium or null alleles at any of these 10 loci and all loci were polymorphic, ranging from 2 to 19 alleles with an average of 8.2 alleles/locus. No locus deviated significantly from Hardy–Weinberg equilibrium, and observed and expected heterozygosities ranged from 0.045–0.864 to 0.097–0.944, respectively. These loci may prove useful to researchers in future evolutionary and ecological studies of declining Terrapene species.
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Isolation and characterization of polymorphic microsatellite loci for the three-toed box turtle (Terrapene carolina triunguis) and cross-amplification in other Terrapene species.
Molecular ecology resources, 2009Co-Authors: A. B. Buchman, Raelynn Deaton, Christopher P. Randle, T. Brummel, E. D. Wilson, William I. LutterschmidtAbstract:We isolated and characterized eight polymorphic microsatellite loci for a Texas population of three-toed box turtle, Terrapene carolina triunguis, using a refined hybridization capture procedure. All eight primer pairs amplified successfully at all loci in seven Texas ornate box turtles (T. ornata ornata). Due to the decline and conservation concerns of North American box turtles, these isolated microsatellites may be a most valuable tool for evaluating baseline population genetic structure for threatened box turtle populations.
Christopher A Phillips - One of the best experts on this subject based on the ideXlab platform.
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blood lactate concentrations in eastern box turtles Terrapene carolina carolina following capture by a canine search team
Journal of Zoo and Wildlife Medicine, 2021Co-Authors: Katy Klein, Laura Adamovicz, Christopher A Phillips, Matthew C. AllenderAbstract:Studies to assess wildlife health commonly evaluate clinical pathology changes, immune responses, pathogen presence, and contaminant exposure, but novel modalities are needed to characterize the unique physiologic responses of reptiles. Lactate is an indicator of hypoperfusion and/or anaerobic respiration and can be quickly and easily measured using a point-of-care analyzer. This study evaluated baseline blood lactate concentrations in free-living eastern box turtles (Terrapene carolina carolina, n = 116) using a point of care analyzer and then determined the effect of handling time, physical examination (PE) abnormalities, and quantitative polymerase chain reaction pathogen detection (Terrapene herpesvirus 1, Mycoplasma sp., Terrapene adenovirus) on lactate concentrations. Blood lactate concentrations were higher in turtles with Terrapene herpesvirus 1 (n = 11), quiet mentation, and increased packed cell volume (P < 0.05). Lactate concentrations increased between initial capture and PE, with peak values reaching 129 min after capture. Lactate at PE was positively associated with baseline lactate concentrations. Turtles with Terrapene herpesvirus 1 may have alterations in blood flow, oxygen delivery, or activity patterns, driving increases in baseline lactate. Increased handling time likely leads to more escape behaviors and/or breath holding, causing turtles to undergo anaerobic metabolism and raising lactate concentrations. Overall, lactate measured by a point of care analyzer shows variability caused by capture and health factors in eastern box turtles and may be a useful adjunctive diagnostic test in this species after full methodologic validation.
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contrasting signatures of introgression in north american box turtle Terrapene spp contact zones
bioRxiv, 2020Co-Authors: Bradley T Martin, Christopher A Phillips, Roger D Birkhead, John S Placyk, Marlis R Douglas, Tyler K Chafin, Michael E DouglasAbstract:Hybridization occurs differentially across the genome in a balancing act between selection and migration. With the unprecedented resolution of contemporary sequencing technologies, selection and migration can now be effectively quantified such that researchers can identify genetic elements involved in introgression. Furthermore, genomic patterns can now be associated with ecologically relevant phenotypes, given availability of annotated reference genomes. We do so in North American box turtles (Terrapene) by deciphering how selection affects hybrid zones at the interface of species boundaries and identifying genetic regions potentially under selection that may relate to thermal adaptations. Such genes may impact physiological pathways involved in temperature-dependent sex determination, immune system functioning, and hypoxia tolerance. We contrasted these patterns across inter- and intra-specific hybrid zones that differ temporally and biogeographically. We demonstrate hybridization is broadly apparent in Terrapene, but with observed genomic cline patterns corresponding to species boundaries at loci potentially associated with thermal adaptation. These loci display signatures of directional introgression within intra-specific boundaries, despite a genome-wide selective trend against intergrades. In contrast, outlier loci for inter-specific comparisons exhibited evidence of being under selection against hybrids. Importantly, adaptations coinciding with species boundaries in Terrapene overlap with climatic boundaries and highlight the vulnerability of these terrestrial ectotherms to anthropogenic pressures.
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erythrocyte sedimentation rate and hemoglobin binding protein in free living box turtles Terrapene spp
PLOS ONE, 2020Co-Authors: Laura Adamovicz, Sarah J Baker, Ethan J Kessler, Marta Kelly, Samantha Johnson, John M Winter, Christopher A Phillips, Matthew C. AllenderAbstract:The acute phase response is a highly conserved reaction to infection, inflammation, trauma, stress, and neoplasia. Acute phase assays are useful for wildlife health assessment, however, they are infrequently utilized in reptiles. This study evaluated erythrocyte sedimentation rate (ESR) in eastern (Terrapene carolina carolina) and ornate box turtles (Terrapene ornata ornata) and hemoglobin-binding protein (HBP) in T. ornata. Erythrocyte sedimentation rate in 90 T. carolina and 105 T. ornata was negatively associated with packed cell volume and was greater in unhealthy turtles (p < 0.05). Female T. ornata had higher ESR values than males (p < 0.05). Measurement of ESR with a microhematocrit tube proportionally overestimated values from a commercial kit (Winpette), though both methods may retain utility with separate reference intervals. Hemoglobin-binding protein concentration in 184 T. ornata was significantly increased in adults and unhealthy turtles (p < 0.05). Erythrocyte sedimentation rate values were similar between seasons and populations, and HBP values were consistent between years, indicating that these analytes may have more stable baseline values than traditional health metrics in reptiles. This study demonstrates that ESR and HBP are promising diagnostics for health assessment in wild box turtles. Incorporating these tests into wild herptile health assessment protocols may support conservation efforts and improve ecosystem health monitoring.
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machine learning substantiates biologically meaningful species delimitations in the phylogenetically complex north american box turtle genus Terrapene
bioRxiv, 2020Co-Authors: Bradley T Martin, Christopher A Phillips, Roger D Birkhead, John S Placyk, Marlis R Douglas, Tyler K Chafin, Michael E DouglasAbstract:Model-based approaches to species delimitation are constrained both by computational capacities as well as by algorithmic assumptions that are frequently violated when applied to biologically complex systems. An alternate approach, demonstrated herein, employs machine learning (=ML) approaches from which species limits are derived without an explicit definition of an underlying species model. By doing so, we demonstrate the capacity of these approaches to designate phylogenomically and biologically relevant groups, using North American box turtles (Terrapene spp.) as an example. Several different ML-based and traditional species delimitation algorithms were invoked to parse a large SNP dataset derived from ddRAD sequencing. Our results illuminate two major findings. First, more traditional model-based approaches perform poorly, a likely reflection of systematic biases inherent in their formulation. Multispecies coalescent methods consistently over-split Terrapene, particularly given prior evidence and our own phylogenetic results. Second, results from ML and clustering algorithms consistently reiterated the presence of clades that were well-supported in prior species tree analyses. In summary, we highlight both the strengths and limitations of ML algorithms, and in doing so, explore appropriate approaches to data manipulation and model fit. Our study was accomplished within the context of a well-characterized empirical system that allowed a direct contrast between ML versus traditional approaches. It allowed the utility of ML-methods to be underscored for species delimitation and serves as a study case from which guidelines implicit to ML methods could be applied to other study systems.
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MORTALITY INVESTIGATION OF MONITORED EASTERN BOX TURTLES (Terrapene CAROLINA CAROLINA) IN CENTRAL ILLINOIS, USA, FROM 2016-18.
Journal of wildlife diseases, 2019Co-Authors: Jeremy M. Rayl, Laura Adamovicz, Marta Kelly, Christopher A Phillips, Adam W Stern, Miranda D. Vieson, Michelle Beermann, Matthew C. AllenderAbstract:Abstract Mortality events in eastern box turtles (Terrapene carolina carolina) threaten conservation efforts across the species range. These events are often under-diagnosed and, when observed, pre...
Tracy A. G. Rittenhouse - One of the best experts on this subject based on the ideXlab platform.
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Demographics and density estimates of two three-toed box turtle (Terrapene carolina triunguis) populations within forest and restored prairie sites in central Missouri
PeerJ, 2015Co-Authors: Kelly M. O’connor, Chadwick D. Rittenhouse, Joshua J. Millspaugh, Tracy A. G. RittenhouseAbstract:Box turtles (Terrapene carolina) are widely distributed but vulnerable to population decline across their range. Using distance sampling, morphometric data, and an index of carapace damage, we surveyed three-toed box turtles (Terrapene carolina triunguis) at 2 sites in central Missouri, and compared differences in detection probabilities when transects were walked by one or two observers. Our estimated turtle densities within forested cover was less at the Thomas S. Baskett Wildlife Research and Education Center, a site dominated by eastern hardwood forest (d = 1.85 turtles/ha, 95% CI [1.13, 3.03]) than at the Prairie Fork Conservation Area, a site containing a mix of open field and hardwood forest (d = 4.14 turtles/ha, 95% CI [1.99, 8.62]). Turtles at Baskett were significantly older and larger than turtles at Prairie Fork. Damage to the carapace did not differ significantly between the 2 populations despite the more prevalent habitat management including mowing and prescribed fire at Prairie Fork. We achieved improved estimates of density using two rather than one observer at Prairie Fork, but negligible differences in density estimates between the two methods at Baskett. Error associated with probability of detection decreased at both sites with the addition of a second observer. We provide demographic data on three-toed box turtles that suggest the use of a range of habitat conditions by three-toed box turtles. This case study suggests that habitat management practices and their impacts on habitat composition may be a cause of the differences observed in our focal populations of turtles.
