| short heatwaves during fluctuating incubation regimes produce females under temperature-dependent sex determination with implications for sex ratios in nature. | patterns of temperature fluctuations in nature affect numerous biological processes, yet, empirical studies often utilize constant temperature treatments. this can limit our understanding of how thermally sensitive species respond to ecologically relevant temperatures. research on turtles with temperature-dependent sex determination (tsd) provides good examples of this, since nest temperatures from many populations rarely exceed those necessary to produce females under constant laboratory condit ... | 2018 | 29311550 |
| a case report of intrarenal epidermoid cysts in a yellow-bellied slider (trachemys scripta scripta). | a 7-year-old yellow-bellied slider exhibited anorexia, decreased activity, generalised wasting of skeletal muscles and oedema. haematology examination revealed increased phosphorus and decreased calcium levels. during necropsy performed after spontaneous death, a focal nodular lesion containing tan amorphous material was found in the left kidney. histopathology examination revealed multiple cystic lesions lined by a multilayered squamous, occasionally cuboidal, and containing keratin. epithelial ... | 2017 | 29306149 |
| experimentally induced selenosis in yellow-bellied slider turtles ( trachemys scripta scripta). | selenosis, or selenium toxicosis, occurs in wildlife and livestock, usually because of excessive intake of selenium via selenium-containing plants. although it is known that wild slider turtles can accumulate large amounts of selenium, little is known about how selenium exposure may affect these reptiles. in this study, the authors report histopathologic changes in yellow-bellied sliders ( trachemys scripta scripta) caused by experimental exposure to selenomethionine. microscopic changes in kidn ... | 2017 | 29291674 |
| melanin deposition ruled out as cause of color changes in the red-eared sliders (trachemys scripta elegans). | animal coloration primarily depends on the presence of pigments and the mixing ratio of eumelanin and pheomelanin. the color of red-eared slider's carapace varies with age, from an olive green to a yellow green, and then to a yellow brown in juveniles, generally. the purpose of the present study was to investigate whether this color change is related to the difference in melanin expression. melanin deposition levels were examined in the carapace, skin, eye and muscle of the three color-types usi ... | 2018 | 29269034 |
| translational regulation in the anoxic turtle, trachemys scripta elegans. | the red-eared slider turtle (trachemys scripta elegans), has developed remarkable adaptive mechanisms for coping with decreased oxygen availability during winter when lakes and ponds become covered with ice. strategies for enduring anoxia tolerance include an increase in fermentable fuel reserves to support anaerobic glycolysis, the buffering of end products to minimize acidosis, altered expression in crucial survival genes, and strong metabolic rate suppression to minimize atp-expensive metabol ... | 2017 | 29243067 |
| concentrations of persistent organic pollutants in plasma from two species of turtle from the tennessee river gorge. | persistent organic pollutants (pops) are characterized by their resistance to degradation, biomagnification, global transport, and adverse toxicological effects. the goal of this study was to determine baseline concentrations of several classes of pops, including polychlorinated biphenyls (pcbs), organochlorine pesticides, and polybrominated diphenyl ethers (pbdes) in two turtle species, the cumberland slider (trachemys scripta troosti) and the common musk turtle (sternotherus odoratus) from the ... | 2009 | 19406450 |
| oviductal sperm storage as a reproductive tactic of turtles. | the oviducts of two species of freshwater turtles were examined throughout the year to determine the distribution of sperm within the oviduct, the locations of stored sperm, and the onset of mating. sperm were stored in undifferentiated tubules and ducts of submucosal glands at the periphery of large glandular segments of the albumen and uterine regions of the oviduct. sperm transfer to females commenced in october in sternotherus odoratus and in january in trachemys scripta. the role of sperm s ... | 2006 | 9803538 |
| characterizing the distribution of steroid sulfatase during embryonic development: when and where might metabolites of maternal steroids be reactivated? | all vertebrate embryos are exposed to maternally derived steroids during development. in placental vertebrates, metabolism of maternal steroids by the placenta modulates embryonic exposure, but how exposure is regulated in oviparous vertebrates is less clear. recent work in oviparous vertebrates has demonstrated that steroids are not static molecules, as they can be converted to more polar steroid sulfates by sulfotransferase enzymes. importantly, these steroid sulfates can be converted back to ... | 2017 | 29074704 |
| venous pressures and cardiac filling in turtles during apnoea and intermittent ventilation. | the amount of blood pumped by the heart (cardiac output) must be matched to the amount of blood returning to the heart (venous return), but the factors determining cardiac filling are sparsely understood in ectothermic vertebrates. stroke volume is affected by heart rate along with central and peripheral venous pressures. in the present study, we investigated the heart rate dependency of cardiac filling in turtles, along with the changes in venous pressures that accompany ventilation. experiment ... | 2017 | 29071420 |
| detection of leptospira spp. in water turtle (trachemys scripta) living in ponds of urban parks. | urban parks are green areas of cities where families and children spend hours outside. turtles often inhabit urban parks. however, even if the animals seem harmless, they may serve as both reservoirs or accidental hosts for different serotypes ofleptospiraspp.leptospiraspp. is a waterborne zoonotic bacterium relevant for public health. reptiles and amphibians may play a role in the epidemiology, transmission, and persistence ofleptospiraspp. in the present study, we observed the presence of anti ... | 2017 | 29056709 |
| cold block ofin vitroeyeblink reflexes: evidence supporting the use of hypothermia as an anesthetic in pond turtles. | use of hypothermia as a means of anesthesia for amphibians and reptiles is prohibited by agencies that establish veterinary guidelines. this has recently been called into question by members of the scientific community based on reviews of published literature. using pond turtles (trachemys scripta elegans), hypothermia as a method for anesthesia to precede euthanasia by decapitation was assessed. turtles were subjected to hypothermia using a cooling followed by freezing protocol. body temperatur ... | 2017 | 28982970 |
| a circuit for detection of interaural time differences in the nucleus laminaris of turtles. | the physiological hearing range of turtles is approximately 50-1000 hz, as determined by cochlear microphonics ( wever and vernon, 1956a). these low frequencies can constrain sound localization, particularly in red-eared slider turtles, which are freshwater turtles with small heads and isolated middle ears. to determine if these turtles were sensitive to interaural time differences (itds), we investigated the connections and physiology of their auditory brainstem nuclei. tract tracing experiment ... | 2017 | 28947499 |
| melanoblast development coincides with the late emerging cells from the dorsal neural tube in turtle trachemys scripta. | ectothermal reptiles have internal pigmentation, which is not seen in endothermal birds and mammals. here we show that the development of the dorsal neural tube-derived melanoblasts in turtle trachemys scripta is regulated by similar mechanisms as in other amniotes, but significantly later in development, during the second phase of turtle trunk neural crest emigration. the development of melanoblasts coincided with a morphological change in the dorsal neural tube between stages mature g15 and g1 ... | 2017 | 28935865 |
| comparative analysis of fmrfamide-like immunoreactivity in caiman (caiman crocodilus) and turtle (trachemys scripta elegans) brains. | the distribution of fmrfamide (fmrfa)-like peptides in caiman (caiman crocodilus) and turtle (trachemys scripta elegans) brains was studied by immunohistochemistry. in both species, distinct groups of fmrfa-like immunoreactive (ir) perikarya were present in the medial septal nucleus, accumbens nucleus, nucleus of the diagonal band of broca, suprachiasmatic area, lateral hypothalamic area, and periventricular hypothalamic nucleus. a few fmrfa-ir neurons in the hypothalamic area were located in th ... | 1999 | 10639745 |
| antinociceptive and respiratory effects following application of transdermal fentanyl patches and assessment of brain μ-opioid receptor mrna expression in ball pythons. | objective to quantify plasma fentanyl concentrations (pfcs) and evaluate antinociceptive and respiratory effects following application of transdermal fentanyl patches (tfps) and assess cerebrospinal μ-opioid receptor mrna expression in ball pythons (compared with findings in turtles). animals 44 ball pythons (python regius) and 10 turtles (trachemys scripta elegans). procedures to administer 3 or 12 μg of fentanyl/h, a quarter or whole tfp (tfp-3 and tfp-12, respectively) was used. at intervals ... | 2017 | 28650234 |
| effect of temperature upon carbon dioxide stores in the snake coluber constrictor and the turtle chrysemys scripta. | the effect of temperature upon respiratory exchange ratio (r) was measured in snakes (coluber constrictor) and turtles (chrysemys scripta). increasing body temperature produced a transient elevation of r, and lowering body temperature transiently depressed r. these thermal effects resulted from an 'excess' and a 'deficit' co2 elimination, respectively. steady-state blood co2 content (cco2) in c. constrictor decreased linearly with rising temperature. plasma bicarbonate concentration, calculated ... | 1988 | 2850333 |
| hemoglobin polymerization via disulfide bond formation in the hypoxia-tolerant turtle trachemys scripta: implications for antioxidant defense and o2transport. | the ability of many reptilian hemoglobins (hbs) to form high-molecular weight polymers, albeit known for decades, has not been investigated in detail. given that turtle hbs often contain a high number of cysteine (cys), potentially contributing to the red blood cell defense against reactive oxygen species, we have examined whether polymerization of hb could occur via intermolecular disulfide bonds in red blood cells of freshwater turtle trachemys scripta, a species that is highly tolerant of hyp ... | 2018 | 28877869 |
| synaptic excitation in spinal motoneurons alternates with synaptic inhibition and is balanced by outward rectification during rhythmic motor network activity. | regular firing in spinal motoneurons of red-eared turtles (trachemys scripta elegans, either sex) evoked by steady depolarization at rest is replaced by irregular firing during functional network activity. the transition caused by increased input conductance and synaptic fluctuations in membrane potential was suggested to originate from intense concurrent inhibition and excitation. we show that the conductance increase in motoneurons during functional network activity is mainly caused by intrins ... | 2017 | 28842417 |
| pharmacokinetics of cefquinome in red-eared slider turtles (trachemys scripta elegans) after single intravenous and intramuscular injections. | the purpose of this study was to evaluate the pharmacokinetics of cefquinome (cfq) following single intravenous (iv) or intramuscular (im) injections of 2 mg/kg body weight in red-eared slider turtles. plasma concentrations of cfq were determined by high-performance liquid chromatography and analyzed using noncompartmental methods. the pharmacokinetic parameters following iv injection were as follows: elimination half-life (t1/2λz) 21.73 ± 4.95 hr, volume of distribution at steady-state (vdss) 0 ... | 2018 | 28833214 |
| effects of selenium exposure on the hematology, innate immunity, and metabolic rate of yellow-bellied sliders (trachemys scripta scripta). | selenium (se) is a naturally occurring essential element that can be toxic to vertebrates at high concentrations. despite studies that have documented that wild reptile species can accumulate copious amounts of se, little is known regarding specific toxicologic effects of se. in this study, 70 juvenile yellow-bellied sliders (trachemys scripta scripta) were exposed to one of three seleno-l-methionine (setmet) treatments (control, n = 24; 15 mg/kg, n = 23; and 30 mg/kg, n = 23) via weekly oral ga ... | 2017 | 28780652 |
| morphologic and cytochemical characteristics of the blood cells of the yellow-bellied slider (trachemys scripta scripta). | the increasing prevalence of yellow-bellied sliders (trachemys scripta scripta) as pets in the european union and also its utilization as animal models for experimental purposes makes crucial an accurate classification of their blood cells. the aim of this work was to provide a morphologic classification based on the cytochemical characteristics of the blood cells of 15 yellow-bellied sliders. cytochemical stains included benzidine peroxidase, chloroacetate esterase, alpha-naphthyl butyrate este ... | 2017 | 28762256 |
| glycopattern analysis of acidic secretion in the intestine of the red-eared slender turtle; trachemys scripta elegans (testudines: emydidae). | the secretion of the goblet cells in the intestine of trachemys scripta elegans was studied in situ by histochemical methods to analyze the diversity of sugar chains, with particular regard to the acidic glycans. conventional histochemical stains (periodic acid-schiff, alcian blue ph 2.5, high iron diamine) and binding with ten fitc-labelled lectins combined with chemical and enzymatic pre-treatments were used to characterize the oligosaccharidic chains. the intestine can be divided into three r ... | 2017 | 28756875 |
| exploration of low temperature microrna function in an anoxia tolerant vertebrate ectotherm, the red eared slider turtle (trachemys scripta elegans). | as a model for vertebrate long-term survival in oxygen-restricted environments, the red-eared slider turtle (trachemys scripta elegans) can adapt at the biochemical level to survive in oxygen-free (anoxic) cold water (<10°c). this impressive ability is enabled through a coordinated suppression of energy-expensive, non-essential, cell processes. this study explored the anoxia-responsive expression of several microrna species (mir-1a, -133, -17, -107, -148a, -21, -103, -210, -20a, -365 and -29b) i ... | 2017 | 28689715 |
| a case of diprosopiasis in trachemys scripta scripta. | this short communication describes a case of diprosopiasis in trachemys scripta scripta imported from florida and farmed for about 4 months by a private owner in palermo, sicily, italy. the water turtle showed the morphological and radiological features characterizing such deformity. this communication aims to advance the knowledge of the reptile's congenital anomalies and suggests the need for more detailed investigations to better understand its pathogenesis. | 2017 | 28675254 |
| mecp2 regulates tet1-catalyzed demethylation, ctcf binding, and learning-dependent alternative splicing of thebdnfgene in turtle. | mecp2mutations underlying rett syndrome cause widespread misregulation of gene expression. functions for mecp2 other than transcriptional are not well understood. in an ex vivo brain preparation from the pond turtletrachemys scripta elegans, an intraexonic splicing event in the brain-derived neurotrophic factor (bdnf) gene generates a truncated mrna transcript in naïve brain that is suppressed upon classical conditioning. mecp2 and its partners, splicing factor y-box binding protein 1 (yb-1) and ... | 2017 | 28594324 |
| effects of topical insulin on second-intention wound healing in the red-eared slider turtle (trachemys scripta elegans) - a controlled study. | compared with mammals, wound healing in reptiles is characterized by reduced wound contraction and longer healing times. the aim of this study is to describe the clinical and histopathological effects of topical insulin on second-intention healing of experimentally induced wounds in skin without dermal bony plates of trachemys scripta elegans exposed to daily variations in ambient temperature and in an aquatic environment. forty-four healthy adult females were assigned to two groups: group 1 (n ... | 2017 | 28587643 |
| seasonal shifts in sex ratios are mediated by maternal effects and fluctuating incubation temperatures. | sex-specific maternal effects can be adaptive sources of phenotypic plasticity. reptiles with temperature-dependent sex determination (tsd) are a powerful system to investigate such maternal effects because offspring phenotype, including sex, can be sensitive to maternal influences such as oestrogens and incubation temperatures.in red-eared slider turtles (trachemys scripta), concentrations of maternally derived oestrogens and incubation temperatures increase across the nesting season; we wanted ... | 2017 | 28584392 |
| reply to the commentary by hillman et al. on: "vascular distensibilities have minor effects on intracardiac shunt patterns in reptiles" by filogonio et al. (2017). | our meta-analysis (filogonio et al., 2017) on central vascular blood flows in a snake (crotalus durissus) and a turtle (trachemys scripta) was motivated by hillman et al.'s (2014) analysis on amphibians to investigate whether cardiac shunt patterns depend on cardiac output and vascular distensibilities. in contrast to hillman et al. (2014), we did not uncover a general trend that supports the notion that cardiac shunts in reptiles are dictated by vascular distensibilities. in addition to our res ... | 2017 | 28550946 |
| dmrt1induces the male pathway in a turtle species with temperature-dependent sex determination. | the molecular mechanism underlying temperature-dependent sex determination (tsd) has been a long-standing mystery; in particular, the thermosensitive genetic triggers for gonadal sex differentiation are largely unknown. here, we have characterized a conserved dm domain gene,dmrt1, in the red-eared slider turtletrachemys scripta(t. scripta), which exhibits tsd. we found thatdmrt1has a temperature-dependent, sexually dimorphic expression pattern, preceding gonadal sex differentiation, and is capab ... | 2017 | 28506988 |
| genetic polymorphisms in aromatase (cyp19a1) are not associated with gonadal phenotypes in red-eared slider turtle hatchlings developed at a pivotal temperature. | embryonic gonad sex in many reptilian species is determined by the incubation temperature of the egg, a differentiation process known as temperature-dependent sex determination (tsd). incubation at the pivotal temperature (pvt) results in approximately an equal number of offspring of both sexes. we investigated the potential contribution of genetic variations that drives the gonadal differentiation into testes or ovaries under this temperature in the red-eared slider turtle (trachemys scripta). ... | 2017 | 28445889 |
| accumulation of coal combustion residues and their immunological effects in the yellow-bellied slider (trachemys scripta scripta). | anthropogenic activities such as industrial processes often produce copious amounts of contaminants that have the potential to negatively impact growth, survival, and reproduction of exposed wildlife. coal combustion residues (ccrs) represent a major source of pollutants globally, resulting in the release of potentially harmful trace elements such as arsenic (as), cadmium (cd), and selenium (se) into the environment. in the united states, ccrs are typically stored in aquatic settling basins that ... | 2017 | 28284546 |
| gene expression profiling in the injured spinal cord oftrachemys scripta elegans: an amniote with self-repair capabilities. | slider turtles are the only known amniotes with self-repair mechanisms of the spinal cord that lead to substantial functional recovery. their strategic phylogenetic position makes them a relevant model to investigate the peculiar genetic programs that allow anatomical reconnection in some vertebrate groups but are absent in others. here, we analyze the gene expression profile of the response to spinal cord injury (sci) in the turtletrachemys scripta elegans. we found that this response comprises ... | 2017 | 28223917 |
| na+/k+-atpase activity in the anoxic turtle (trachemys scripta) brain at different acclimation temperature. | survival of prolonged anoxia requires a balance between cellular atp demand and anaerobic atp supply from glycolysis, especially in critical tissues such as the brain. to add insight into the atp demand of the brain of the anoxia-tolerant red-eared slider turtle (trachemys scripta) during prolonged periods of anoxic submergence, we quantified and compared the number of na+-k+-atpase units and their molecular activity in brain tissue from turtles acclimated to either 21°c or 5°c and exposed to ei ... | 2017 | 28089857 |
| temperature shift alters dna methylation and histone modification patterns in gonadal aromatase (cyp19a1) gene in species with temperature-dependent sex determination. | the environment surrounding the embryos has a profound impact on the developmental process and phenotypic outcomes of the organism. in species with temperature-dependent sex determination, gonadal sex is determined by the incubation temperature of the eggs. a mechanistic link between temperature and transcriptional regulation of developmental genes, however, remains elusive. in this study, we examine the changes in dna methylation and histone modification patterns of the aromatase (cyp19a1) gene ... | 2016 | 27902763 |
| the effect of environmental temperature on reptilian peripheral blood b cell functions. | recent studies have identified phagocytic b cells in a variety of species, yet little is understood about their function and how it is influenced by natural environmental variation, such as temperature. phagocytic b-cells are present in red-eared slider turtles, trachemys scripta, and the wide range of temperatures experienced by these ectotherms may have an effect on immunity, including b cell antibody secretion and phagocytosis. we examined the impact of environmental temperature on b cell fun ... | 2017 | 27816625 |
| thyroid hormone modulates offspring sex ratio in a turtle with temperature-dependent sex determination. | the adaptive significance of temperature-dependent sex determination (tsd) has attracted a great deal of research, but the underlying mechanisms by which temperature determines the sex of a developing embryo remain poorly understood. here, we manipulated the level of a thyroid hormone (th), triiodothyronine (t3), during embryonic development (by adding excess t3to the eggs of the red-eared slider turtle trachemys scripta, a reptile with tsd), to test two competing hypotheses on the proximate bas ... | 2016 | 27798296 |
| thermal and substrate color-induced melanization in laboratory reared red-eared sliders (trachemys scripta elegans). | color and pigmentation patterns of the integument can facilitate crypsis, thermoregulation, and social signaling. according to the "thermal melanism hypothesis", cold environmental temperature should increase the quantity of melanin that is deposited in the integument thereby facilitating radiative warming. we studied the influences of water temperature (26°c or 31°c) and substrate color (black or white) on the degree of melanization in the red-eared slider, trachemys scripta elegans, under labo ... | 2016 | 27712654 |
| a timecourse analysis of systemic and gonadal effects of temperature on sexual development of the red-eared slider turtle trachemys scripta elegans. | temperature dependent sex determination (tsd) is the process by which the environmental temperature experienced during embryogenesis influences the sex of an organism, as in the red-eared slider turtle trachemys scripta elegans. in accord with current paradigms of vertebrate sex determination, temperature is believed to exert its effects on sexual development in t. scripta entirely within the middle third of development, when the gonad is forming. however, whether temperature regulates the trans ... | 2016 | 27671871 |
| continuous arterial po2 profiles in unrestrained, undisturbed aquatic turtles during routine behaviors. | mammals and birds maintain high arterial partial pressure of oxygen (po2) values in order to preserve near-complete hemoglobin (hb) oxygen (o2) saturation. in diving mammals and birds, arterial o2follows a primarily monotonic decline and then recovers quickly after dives. in laboratory studies of submerged freshwater turtles, arterial o2depletion typically follows a similar pattern. however, in these studies, turtles were disturbed, frequently tethered to external equipment and confined either t ... | 2016 | 27618860 |
| response of the jak-stat signaling pathway to oxygen deprivation in the red eared slider turtle, trachemys scripta elegans. | the red-eared slider turtle, trachemys scripta elegans, is a model organism commonly used to study the environmental stress of anoxia. it exhibits multiple biochemical adaptations to ensure its survival during the winter months where quantities of oxygen are largely depleted. we proposed that jak-stat signaling would display stress responsive regulation to mediate the survival of the red-eared slider turtle, trachemys scripta elegans, during anoxic stress. importantly, the jak-stat signaling pat ... | 2016 | 27502419 |
| correction: pharmacokinetics of meloxicam in red-eared slider turtles (trachemys scripta elegans) after single intravenous and intramuscular injections. | | 2016 | 27463557 |
| effect of atrazine on immunocompetence of red-eared slider turtle(trachemys scripta). | the impact of agrichemicals on aquatic vertebrate species has been a matter of increasing concern to researchers and environmentalist. the present study aimed to evaluate the effect of atrazine (atz), a worldwide used herbicide, on some immune parameters of red-eared slider (trachemys scripta). twenty-four turtles (2 years old) were randomly distributed in four groups. three groups were intraperitoneally injected once with one of three different doses of atrazine (0.01, 0.1 or 1.0 ng/g body mass ... | 2016 | 27417299 |
| metabolic adaptations supporting anoxia tolerance in reptiles: recent advances. | animal survival during severe hypoxia and/or anoxia is enhanced by a variety of biochemical adaptations including adaptations of fermentative pathways of energy production and, most importantly, the ability to sharply reduce metabolic rate by 5-20 fold and enter a hypometabolic state. the biochemical regulation of metabolic arrest is proving to have common molecular principles that extend across phylogenetic lines and that are conserved in different types of arrested states (not only anaerobiosi ... | 1996 | 8936040 |
| hydric environmental effects on turtle development and sex ratio. | experimental and field studies of different turtle species suggest that moisture influences embryonic development and sex ratios, wetter substrates tend to produce more males, and drier substrates produce more females. in this study, we used trachemys scripta elegans to test the effect of moisture on embryonic development and sex ratios. t. s. elegans eggs were incubated under different temperature and moisture regimes. we monitored embryonic development until stage 22 (after sex determination) ... | 2017 | 29217120 |
| predation risk affects growth and reproduction of an invasive snail and its lethal effect depends on prey size. | the behavior of invasive species under predation risk has been studied extensively, but their growth and reproductive responses have rarely been investigated. we conducted experiments with juveniles and adults of the invasive freshwater snail pomacea canaliculata, and we observed changes in growth and reproduction in response to predation risk from a caged predator (trachemys scripta elegans). p. canaliculata produced eggs earlier in the presence of predators and injured conspecifics compared wi ... | 2017 | 29136660 |
| clinical and histological findings of cutaneous wound healing in the red-eared slider turtle (trachemys scripta elegans) housed in unheated outdoor enclosures. | cutaneous wounds are common in chelonians. the clinical and histological features of wound healing in these species are not well described and this prevents evaluation of new therapies. | 2016 | 27324567 |
| irregular firing and high-conductance states in spinal motoneurons during scratching and swimming. | intense synaptic transmission during scratch network activity increases conductance and induces irregular firing in spinal motoneurons. it is not known whether this high-conductance state is a select feature for scratching or a property that goes with spinal motor network activity in general. here we compare conductance and firing patterns in spinal motoneurons during network activity for scratching and swimming in an ex vivo carapace-spinal cord preparation from adult turtles (trachemys scripta ... | 2016 | 27225769 |
| systematization and description of the internal carotid arteries and their main ramifications at the brain base in turtles (trachemys scripta elegans). | thirty turtle brains (trachemys scripta elegans) were injected with latex to systematize and describe the internal carotid arteries and their main ramifications at the brain base. the internal carotid arteries had one intercarotid anastomosis. at the level of the tuber cinereum, the internal carotid artery bifurcated into its terminal branches, the rostral and the caudal branches. the rostral branch emitted the rostral choroid artery, the orbital artery, and a series of middle cerebral arteries. ... | 2016 | 27145530 |
| development of the turtle plastron, the order-defining skeletal structure. | the dorsal and ventral aspects of the turtle shell, the carapace and the plastron, are developmentally different entities. the carapace contains axial endochondral skeletal elements and exoskeletal dermal bones. the exoskeletal plastron is found in all extant and extinct species of crown turtles found to date and is synaptomorphic of the order testudines. however, paleontological reconstructed transition forms lack a fully developed carapace and show a progression of bony elements ancestral to t ... | 2016 | 27114549 |
| pharmacokinetics of meloxicam in red-eared slider turtles (trachemys scripta elegans) after single intravenous and intramuscular injections. | objective to determine the pharmacokinetics of meloxicam after single iv and im injections in red-eared slider turtles (trachemys scripta elegans). animals 8 healthy red-eared slider turtles. procedures turtles received 1 dose of meloxicam (0.2 mg/kg) iv or im (4 turtles/route), a 30-day washout period was provided, and then turtles received the same dose by the opposite route. blood samples were collected at predetermined times for measurement of plasma meloxicam concentration. pharmacokinetic ... | 2016 | 27111010 |
| cardiovascular function, compliance, and connective tissue remodeling in the turtle, trachemys scripta, following thermal acclimation. | low temperature directly alters cardiovascular physiology in freshwater turtles, causing bradycardia, arterial hypotension, and a reduction in systemic blood pressure. at the same time, blood viscosity and systemic resistance increase, as does sensitivity to cardiac preload (e.g., via the frank-starling response). however, the long-term effects of these seasonal responses on the cardiovascular system are unclear. we acclimated red-eared slider turtles to a control temperature (25°c) or to chroni ... | 2016 | 27101300 |
| do prion protein gene polymorphisms induce apoptosis in non-mammals? | genetic variations such as single nucleotide polymorphisms (snps) in prion protein coding gene, prnp, greatly affect susceptibility to prion diseases in mammals. here, the coding region of prnp was screened for polymorphisms in redeared turtle, trachemys scripta. four polymorphisms, l203v, n205i, v225a and m237v, were common in 15 out of 30 turtles; in one sample, three snps, l203v, n205i and m237v, and in the remaining 14 samples, only l203v and n205i polymorphisms, were investigated. besides, ... | 2016 | 26949092 |
| the role of dna methylation during anoxia tolerance in a freshwater turtle (trachemys scripta elegans). | oxygen deprivation is a lethal stress that only a few animals can tolerate for extended periods. this study focuses on analyzing the role of dna methylation in aiding natural anoxia tolerance in a champion vertebrate anaerobe, the red-eared slider turtle (trachemys scripta elegans). we examined the relative expression and total enzymatic activity of four dna methyltransferases (dnmt1, dnmt2, dnmt3a and dnmt3b), two methyl-binding domain proteins (mbd1 and mbd2), and relative genomic levels of 5- ... | 2016 | 26843075 |
| how important is the eggshell as a source for initial acquisition of salmonella in hatchling turtles? | how and when turtles first acquire gut microflora is largely speculative. in this study, the eggshell and hatching process were evaluated for their role in the initial acquisition of salmonella, by red-eared slider turtles (trachemys scripta elegans). first, we examined whether the eggshell is a viable substrate for bacterial persistence during incubation, and if internal egg components (i.e., albumen, yolk, and embryo) have detectable bacterial loads. second, we experimentally manipulated salmo ... | 2016 | 26817746 |
| pharmacokinetic profiles of meloxicam in turtles (trachemys scripta scripta) after single oral, intracoelomic and intramuscular administrations. | meloxicam is an anti-inflammatory and analgesic drug used to treat many pathological conditions in turtles. with the aim to fill the lack of data about its pharmacokinetic in this species, eighteen turtles (trachemys scripta scripta) were divided in three groups and treated with a single dose of meloxicam (0.2 mg/kg) by intramuscular, intracoelomic and oral route, respectively. at scheduled time points, blood samples were collected and meloxicam concentrations were determined by hplc. pharmacoki ... | 2016 | 26789011 |
| ultrastructural characteristics of blood cells in the yellow-bellied slider turtle (trachemys scripta scripta). | the classification of blood cells from the yellow-bellied slider turtle (trachemys scripta scripta) is relevant due to their increasing importance as pets and as object of study in clinical settings and research projects. however, no previous ultrastructural characterization of blood cells from turtles of the genus trachemys has been reported. | 2016 | 26780166 |
| mitochondrial responses to prolonged anoxia in brain of red-eared slider turtles. | mitochondria are central to aerobic energy production and play a key role in neuronal signalling. during anoxia, however, the mitochondria of most vertebrates initiate deleterious cell death cascades. nonetheless, a handful of vertebrate species, including some freshwater turtles, are remarkably tolerant of low oxygen environments and survive months of anoxia without apparent damage to brain tissue. this tolerance suggests that mitochondria in the brains of such species are adapted to withstand ... | 2016 | 26763217 |
| temperature experienced during incubation affects antioxidant capacity but not oxidative damage in hatchling red-eared slider turtles (trachemys scripta elegans). | our understanding of how oxidative stress resistance phenotypes are affected by the developmental environment is limited. one component of the developmental environment, which is likely central to early life oxidative stress among ectothermic and oviparous species, is that of temperature. we investigated how incubation temperature manipulations affect oxidative damage and total antioxidant capacity (tac) in red-eared slider turtle (trachemys scripta elegans) hatchlings. first, to determine wheth ... | 2016 | 26685171 |
| turtle hatchlings show behavioral types that are robust to developmental manipulations. | there can be substantial variation among individuals within a species in how they behave, even under similar conditions; this pattern is found in many species and across taxa. however, the mechanisms that give rise to this behavioral variation are often unclear. this study investigated the influence of environmental manipulations during development on behavioral variation in hatchlings of the red-eared slider turtle (trachemys scripta). first, we examined the effects of three manipulations durin ... | 2016 | 26657026 |
| the metabolic cost of breathing in red-eared sliders: an attempt to resolve an old controversy. | accurately measuring the metabolic cost of breathing in turtles has been a challenge with cost estimates varying greatly between different studies and/or methods used. to determine the source of discrepancy, we calculated costs using two methods in a single group of red-eared sliders (trachemys scripta elegans). the unidirectional ventilation method yielded an estimate of 3.3ml o2/l air ventilated while the regression method (using hypoxia as a respiratory stimulus) produced an estimate of 0.8ml ... | 2016 | 26524718 |
| modeling commercial freshwater turtle production on us farms for pet and meat markets. | freshwater turtles are being exploited for meat, eggs, traditional medicine, and pet trade. as a response, turtle farming became a booming aquaculture industry in the past two decades, specifically in the southeastern states of the united states of america (us) and across southeast asia. however, us turtle farms are currently producing turtles only for the pet trade while commercial trappers remain focused on catching the largest individuals from the wild. in our analyses we have created a biolo ... | 2015 | 26407157 |
| bi-modal strategy of gastrulation in reptiles. | amniote gastrulation is often described with respect to human, mouse and chick development by the presence of the primitive streak, a posterior-to-anterior midline morphological cell ingression feature that has come to define amniote gastrulation. how this midline, ingression-based strategy of gastrulation evolved from the ancestral blastopore, a circumferential involution event in anamniotes, is unknown. however, within the amniote clade there exists a more diverse range of gastrulation strateg ... | 2015 | 26088476 |
| limb bone loading in swimming turtles: changes in loading facilitate transitions from tubular to flipper-shaped limbs during aquatic invasions. | members of several terrestrial vertebrate lineages have returned to nearly exclusive use of aquatic habitats. these transitions were often accompanied by changes in skeletal morphology, such as flattening of limb bone shafts. such morphological changes might be correlated with the exposure of limb bones to altered loading. though the environmental forces acting on the skeleton differ substantially between water and land, no empirical data exist to quantify the impact of such differences on the s ... | 2015 | 26085496 |
| the red-eared slider turtle carapace under fatigue loading: the effect of rib-suture arrangement. | biological structures consisting of strong boney elements interconnected by compliant but tough collagenous sutures are abundantly found in skulls and shells of, among others, armadillos, alligators, turtles and more. in the turtle shell, a unique arrangement of alternating rigid (rib) and flexible (suture) elements gives rise to superior mechanical performance when subjected to low and high strain-rate loadings. however, the resistance to repeated load cycling - fatigue - of the turtle shell ha ... | 2015 | 26042699 |
| the in ovo conversion of oestrone to oestrone sulfate is rapid and subject to inhibition by bisphenol a. | vertebrate embryos develop in the presence of maternally derived steroids. while these steroids can influence development, embryonic enzymes are thought to buffer some steroid sensitive processes, such as gonadal differentiation, from the effects of maternal steroids. many of these same enzymes may also buffer the embryo from chemicals present in the environment, but this may alter their capacity to metabolize maternal steroids. here, we characterized the ability of red-eared slider (trachemys s ... | 2015 | 25904318 |
| preparation and application of an innovative thrombocyte/leukocyte-enriched plasma to promote tissue repair in chelonians. | platelet concentrates are widely used in mammalian regenerative medicine to improve tissue healing. chelonians (testudines) would benefit from the application of thrombocyte preparations to regenerate damaged tissues, since traumatic injuries are leading causes of morbidity and mortality for both wild-living and domesticated animals. the aim of this study was to establish a protocol that optimized the recovery of the thrombocytes from blood samples and to show the efficacy of thrombocyte-enriche ... | 2015 | 25901960 |
| acute and chronic temperature effects on cardiovascular regulation in the red-eared slider (trachemys scripta). | acute and chronic changes in ambient temperature alter several aspects of reptilian physiology. we investigated the effects of each type of temperature change on reptilian cardiovascular regulation in red-eared slider turtles (trachemys scripta), a species known to experience marked seasonal changes in ambient temperature. turtles were instrumented with occlusive catheters in the femoral artery and vein. following an acclimation period of 10 days at 13 °c (13(1)), cardiovascular responses to adr ... | 2015 | 25774046 |
| reproduction and hatchling performance in freshwater turtles associated with a remediated coal fly-ash spill. | in 2008 an impoundment retaining wall failed at the tennessee valley authority's coal burning plant in kingston, tennessee, releasing large quantities of coal-fly ash into the emory river. following extensive remediation of the spill, we captured (in 2011 and 2012) gravid turtles of multiple species in three rivers (two impacted and one reference) within the vicinity of the spill to determine whether there was evidence of the spill influencing reproduction. there was little evidence that river o ... | 2015 | 25682257 |
| surgery and electrochemotherapy for the treatment of cutaneous squamous cell carcinoma in a yellow-bellied slider (trachemys scripta scripta). | a 5-year-old female yellow-bellied slider (trachemys scripta scripta) was referred for evaluation of a 2-month nonhealing ulcerated mass on the dorsal aspect of the neck. | 2015 | 25632821 |
| pharmacokinetic/pharmacodynamic assessments of 10 mg/kg tramadol intramuscular injection in yellow-bellied slider turtles (trachemys scripta scripta). | in reptiles, administration of opioid drugs has yielded unexpected results with respect to analgesia. the aims of this study were to assess the pharmacokinetic/pharmacodynamic (pk/pd) properties of tramadol and its active metabolite m1 and to evaluate the effect of the renal portal system on the pk/pd parameters in yellow-bellied slider turtles. turtles (n = 19) were randomly assigned to four treatment groups, according to a masked, single-dose, four-treatment, unpaired, four-period crossover de ... | 2015 | 25623330 |
| distribution and innervation of putative peripheral arterial chemoreceptors in the red-eared slider (trachemys scripta elegans). | peripheral arterial chemoreceptors have been isolated to the common carotid artery, aorta, and pulmonary artery of turtles. however, the putative neurotransmitters associated with these chemoreceptors have not yet been described. the goal of the present study was to determine the neurochemical content, innervations, and distribution of putative oxygen-sensing cells in the central vasculature of turtles and to derive homologies with peripheral arterial chemoreceptors of other vertebrates. we used ... | 2015 | 25586499 |
| evaluation of plasma fibrinogen concentration as a diagnostic indicator of inflammation in red-eared sliders (trachemys scripta elegans). | to critically evaluate plasma fibrinogen concentration as a diagnostic indicator of inflammation in red-eared sliders (trachemys scripta elegans). | 2015 | 25554942 |
| hypoxia switches episodic breathing to singlet breathing in red-eared slider turtles (trachemys scripta) via a tropisetron-sensitive mechanism. | hypoxia-induced changes in the chelonian breathing pattern are poorly understood. thus, breathing was measured in freely swimming adult red-eared slider turtles breathing air prior to breathing nitrogen for 4h. ventilation increased 10-fold within 10min due to increased breath frequency and tidal volume. breaths/episode decreased by ∼50% within after 1h of hypoxia while the number of singlet breaths increased from 3.1±1.6singlets/h to a maximum of 66.1±23.5singlets/h. expiratory and inspiratory ... | 2015 | 25543027 |
| complete mitochondrial genomes of the yellow-bellied slider turtle trachemys scripta scripta and anoxia tolerant red-eared slider trachemys scripta elegans. | the complete mitochondrial genomes of the yellow-bellied slider (trachemys scripta scripta) and anoxia tolerant red-eared slider (trachemys scripta elegans) turtles were sequenced to analyze gene arrangement. the complete mt genomes of t. s. scripta and elegans were circular molecules of 16,791 bp and 16,810 bp in length, respectively, and included an a + 1 frameshift insertion in nd3 and nd4l genes. the at content of the overall base composition of scripta and elegans was 61.2%. nucleotide sequ ... | 2016 | 25541313 |
| respiratory neuron characterization reveals intrinsic bursting properties in isolated adult turtle brainstems (trachemys scripta). | it is not known whether respiratory neurons with intrinsic bursting properties exist within ectothermic vertebrate respiratory control systems. thus, isolated adult turtle brainstems spontaneously producing respiratory motor output were used to identify and classify respiratory neurons based on their firing pattern relative to hypoglossal (xii) nerve activity. most respiratory neurons (183/212) had peak activity during the expiratory phase, while inspiratory, post-inspiratory, and novel pre-expi ... | 2016 | 25462012 |
| chronology, magnitude and duration of expression of putative sex-determining/differentiation genes in a turtle with temperature-dependent sex determination. | the red-eared slider turtle (trachemys scripta) possesses temperature-dependent sex determination (tsd) in which the incubation temperature determines gonadal sex. although a number of mammalian gene homologues have been identified in reptiles with tsd, the exact sex-determining trigger(s) is not known. to date, the current study represents the most comprehensive simultaneous evaluation of the chronology of mrna expression profiles of putative sex-determining/differentiation genes (dmrt1, sox9, ... | 2014 | 25427533 |
| understanding the biological invasion risk posed by the global wildlife trade: propagule pressure drives the introduction and establishment of nearctic turtles. | biological invasions are a key component of human-induced global change. the continuing increase in global wildlife trade has raised concerns about the parallel increase in the number of new invasive species. however, the factors that link the wildlife trade to the biological invasion process are still poorly understood. moreover, there are analytical challenges in researching the role of global wildlife trade in biological invasions, particularly issues related to the under-reporting of introdu ... | 2015 | 25363272 |
| upregulation of hsp72 mediates anoxia/reoxygenation neuroprotection in the freshwater turtle via modulation of ros. | the neuroprotective role of hsp72 has been demonstrated in several ischemic/stroke models to occur primarily through mediation of apoptotic pathways, and a number of heat shock proteins are upregulated in animal models capable of extended anoxic survival. in the present study, we investigated the role of hsp72 on cell death and apoptotic regulators in one anoxia tolerant model system, the freshwater turtle trachemys scripta. since hsp72 is known to regulate apoptosis through interactions with bc ... | 2014 | 25107858 |
| embryonic pcb exposure alters phenotypic, genetic, and epigenetic profiles in turtle sex determination, a biomarker of environmental contamination. | in species with temperature-dependent sex determination, embryonic gonadal differentiation can be modified by exposure to exogenous chemicals such as environmental contaminants. although phenotypic outcomes of such events are well documented, the underlying molecular mechanisms are rarely described. here we examine the genetic and epigenetic effect of the embryonic exposure to polychlorinated biphenyls (pcbs) on gonad differentiation in red-eared slider turtles (trachemys scripta). some pcb cong ... | 2014 | 25105783 |
| dense distributed processing in a hindlimb scratch motor network. | in reduced preparations, hindlimb movements can be generated by a minimal network of neurons in the limb innervating spinal segments. the network of neurons that generates real movements is less well delineated. in an ex vivo carapace-spinal cord preparation from adult turtles (trachemys scripta elegans), we show that ventral horn interneurons in mid-thoracic spinal segments are functionally integrated in the hindlimb scratch network. first, mid-thoracic interneurons receive intense synaptic inp ... | 2014 | 25100606 |
| evaluation of rebound tonometry in red-eared slider turtles (trachemys scripta elegans). | to evaluate feasibility and accuracy of intraocular pressure (iop) measurement by rebound tonometry in adult red-eared slider turtles and determine the effects of manual and chemical restraint on iop. | 2014 | 25097909 |
| honest sexual signaling in turtles: experimental evidence of a trade-off between immune response and coloration in red-eared sliders trachemys scripta elegans. | sexual signals can be evolutionarily stable if they are honest and condition dependent or costly to the signaler. one possible cost is the existence of a trade-off between maintaining the immune system and the elaboration of ornaments. this hypothesis has been experimentally tested in some groups of animals but not in others such as turtles. we experimentally challenged the immune system of female red-eared sliders trachemys scripta elegans, with a bacterial antigen (lipopolysaccharide (lps)) wi ... | 2014 | 25091549 |
| an alternative staining method for counting red-eared slider turtle (trachemys scripta) blood cells using crystal violet in cells diluted with 0.45% sodium chloride. | various staining methods are available for reptilian species blood cell quantification. however, these methods have shown inaccurate differentiation limitations. the current study evaluates staining effects and blood cell counting results using an alternative method, counting blood cells diluted with 0.45% sodium chloride solution and stained with crystal violet. blood samples from 8 red-eared slider turtles (trachemys scripta) were collected. red and white blood cell counts were performed using ... | 2014 | 25080443 |
| phallus development in the turtle trachemys scripta. | development of a phallus occurs in almost all amniotes; however, considerable variation in phallus morphology among different amniote lineages has contributed to the debate about their structural homology. mammals are the only amniotes that form a closed urethral tube within the penis. in contrast, the phallus of reptiles and birds has an open urethral groove, or sulcus spermaticus, that facilitates directional flow of sperm along the penis. one condition of structural homology is that the organ ... | 2015 | 24969757 |
| activation of the carbohydrate response element binding protein (chrebp) in response to anoxia in the turtle trachemys scripta elegans. | chrebp (carbohydrate response element binding protein) is a glucose-responsive transcription factor that is known to be an important regulator of glycolytic and lipogenic genes in response to glucose. we hypothesized that activation of chrebp could be relevant to anoxia survival by the anoxia-tolerant turtle, trachemys scripta elegans. | 2014 | 24931694 |
| adenosinergic regulation of the cardiovascular system in the red-eared slider trachemys scripta. | few studies have investigated adenosinergic regulation of the cardiovascular system in reptiles. the haemodynamic effect of a bolus intra-arterial adenosine injection (2.5 μm kg⁻¹) was investigated in nine anaesthetised red-eared sliders (trachemys scripta). adenosine caused a transient bradycardia, which was accompanied by systemic vasodilatation as evidenced by an increase in systemic flow and a decrease in systemic pressure. meanwhile, pulmonary flow fell significantly. both the bradycardia a ... | 2014 | 24726607 |
| modelling favourability for invasive species encroachment to identify areas of native species vulnerability. | we assessed the vulnerability of the native mediterranean pond turtle to encroachment by the invasive red-eared slider in southern spain. we first obtained an ecogeographical favourability model for the mediterranean pond turtle. we then modelled the presence/absence of the red-eared slider in the mediterranean pond turtle range and obtained an encroachment favourability model. we also obtained a favourability model for the red-eared slider using the ecogeographical favourability for the mediter ... | 2014 | 24719577 |
| recognition of an important water quality issue at zoos: prevalence and potential threat of toxic cyanobacteria. | zoo animals may be particularly vulnerable to water sources contaminated with cyanobacterial toxins given their nonvoluntary close association with this resource. however, the prevalence and potential threat of toxic cyanobacteria in this setting are unknown. several otherwise unexplained yellow-bellied slider (trachemys scripta scripta) deaths were documented in a zoo moat with recurring blooms of toxic microcystis aeruginosa. furthermore, an extremely high and potentially lethal concentration ... | 2014 | 24712178 |
| a high-throughput protocol for message rna quantification using rna dot-blots. | this study develops a method to rapidly measure the relative abundance of mrna in total rna samples using a dot-blotting technique and biotin-labeled detection probes that recognize the polyadenylate tail on mrna. we demonstrate the effectiveness of this technique by determining the relative total amounts of mrna in three tissues of turtles (trachemys scripta elegans) exposed to normoxic versus anoxic conditions. the data emphasize the usefulness of the method for the simple and rapid analysis o ... | 2014 | 24560727 |
| golgi study of medium spiny neurons from dorsolateral striatum of the turtle trachemys scripta elegans. | comparative anatomy has shown similarities between reptilian and mammalian basal ganglia. here the morphological characteristics of the medium spiny neurons (msn) in the dorsolateral striatum (dls) of the turtle are described after staining them with the golgi technique. the soma of msn in dls showed three main forms: spherical, ovoid, and fusiform. the number of primary dendritic branches (3-4 dendrites/cell) was less than observed in mammals. the msn axon originates mainly from the soma, and r ... | 2013 | 24513300 |
| golgi study of medium spiny neurons from dorsolateral striatum of the turtle trachemys scripta elegans. | comparative anatomy has shown similarities between reptilian and mammalian basal ganglia. here the morphological characteristics of the medium spiny neurons (msn) in the dorsolateral striatum (dls) of the turtle are described after staining them with the golgi technique. the soma of msn in dls showed three main forms: spherical, ovoid, and fusiform. the number of primary dendritic branches (3-4 den-drites/cell) was less than observed in mammals. the msn axon originates mainly from the soma, and ... | 2013 | 24511608 |
| the efficacy of intracoelomic fospropofol in red-eared sliders (trachemys scripta elegans). | intravenous anesthetic delivery in reptiles can be challenging. current injectable techniques have varied induction/recovery times and anesthetic quality. this study hypothesized that intracoelomic administration of a new anesthetic, fospropofol, in turtles would result in dose-dependent anesthesia and respiratory depression. a two-part prospective trial using adult red-eared slider turtles (trachemys scripta elegans) weighing 764 +/- 17 g was conducted to determine an effective anesthetic dose ... | 2013 | 24450053 |
| genomic organization and identification of promoter regions for the bdnf gene in the pond turtle trachemys scripta elegans. | brain-derived neurotrophic factor (bdnf) is an important regulator of neuronal development and synaptic function. the bdnf gene undergoes significant activity-dependent regulation during learning. here, we identified the bdnf promoter regions, transcription start sites, and potential regulatory sequences for bdnf exons i-iii that may contribute to activity-dependent gene and protein expression in the pond turtle trachemys scripta elegans (tbdnf). by using transfection of bdnf promoter/luciferase ... | 2014 | 24443176 |
| radial glia in the proliferative ventricular zone of the embryonic and adult turtle, trachemys scripta elegans. | to better understand the role of radial glial (rg) cells in the evolution of the mammalian cerebral cortex, we investigated the role of rg cells in the dorsal cortex and dorsal ventricular ridge of the turtle, trachemys scripta elegans. unlike mammals, the glial architecture of adult reptile consists mainly of ependymoradial glia, which share features with mammalian rg cells, and which may contribute to neurogenesis that continues throughout the lifespan of the turtle. to evaluate the morphology ... | 2014 | 27504470 |
| bending mechanics of the red-eared slider turtle carapace. | the turtle shell is a natural shield that possesses complex hierarchical structure, giving rise to superior mechanical properties. the keratin-covered boney top (dorsal) part of the shell, termed carapace, is composed of rigid sandwich-like ribs made of a central foam-like interior flanked by two external cortices. the ribs are attached to one another in a 3-d interdigitated manner at soft unmineralized collagenous sutures. this unique structural combination promotes sophisticated mechanical res ... | 2014 | 24333673 |
| predetermination of sexual fate in a turtle with temperature-dependent sex determination. | egg incubation temperature determines offspring sex in many reptilian species, including red-eared slider turtles, where embryos incubated at low temperatures during the initial stages of gonad formation develop as males, while those kept at higher temperatures develop as females. incubation at the threshold, or pivotal, temperature (pvt) yields an even ratio of males and females. this strong susceptibility to temperature indicates that each embryo of this species is competent to develop as a ma ... | 2014 | 24316144 |
| morphological and mechanical changes in juvenile red-eared slider turtle (trachemys scripta elegans) shells during ontogeny. | turtles experience numerous modifications in the morphological, physiological, and mechanical characteristics of their shells through ontogeny. although a general picture is available of the nature of these modifications, few quantitative studies have been conducted on changes in turtle shell shape through ontogeny, and none on changes in strength or rigidity. this study investigates the morphological and mechanical changes that juvenile trachemys scripta elegans undergo as they increase in size ... | 2014 | 24301373 |
| prevalence of selected pathogens in western pond turtles and sympatric introduced red-eared sliders in california, usa. | pathogen introduction by invasive species has been speculated to be a cause of declining western pond turtle emys marmorata populations in california, usa. this study determined the prevalence of ranavirus spp., herpesvirus spp., mycoplasma spp. (via polymerase chain reaction of blood and nasal flush contents), and salmonella spp. infection (via fecal culture) in native e. marmorata and invasive red-eared sliders trachemys scripta elegans and compared infection prevalence in e. marmorata populat ... | 2013 | 24270022 |
| [spectra analysis reveals the sexual dichromatism of red-eared slider turtle(trachemys scripta)]. | in this study,spectra analysis was conducted to investigate the sexual dichromatism and relationship between body color and quality of the red-eared slider turtle (trachemys scripta). visual modeling revealed that the differences of the hues of body colors' ultraviolet (uv) components between male and female were significant. moreover, the visible(vis)components of the hues of forelimbs were correlated with body qualities of male but not of female. our results indicated that uv might act as a si ... | 2013 | 24115659 |
| effects of body position and extension of the neck and extremities on lung volume measured via computed tomography in red-eared slider turtles (trachemys scripta elegans). | to determine the effects of body position and extension of the neck and extremities on ct measurements of ventilated lung volume in red-eared slider turtles (trachemys scripta elegans). | 2013 | 24094268 |