Emydomyces testavorans Surveillance in Multiple Free-Ranging Terrestrial and Aquatic Chelonian Species in Illinois, USA.

The order Onygenales contains multiple fungal pathogens that affect free-ranging and zoo-housed reptilian species. Emydomyces testavorans, an onygenalean fungus associated with skin and shell disease, has been sporadically detected in aquatic chelonians. Because of the recent discovery of this organism, little is known about its prevalence in free-ranging chelonians. The objective of this study was to perform surveillance for E. testavorans in six free-ranging aquatic and terrestrial chelonian species in Illinois, USA: Blanding's turtles (n=437; Emydoidea blandingii), painted turtles (n=199; Chrysemys picta), common snapping turtles (n=35; Chelydra serpentina), red-eared sliders (n=62; RES; Trachemys scripta elegans), eastern box turtles (n=73; Terrapene carolina carolina) and ornate box turtles (n=29; Terrapene carolina ornata). Combined cloacal-oral swabs (COSs) or shell (carapace and plastron surfaces) swabs were collected from 2019 to 2021 and tested for E. testavorans using quantitative PCR. The PCR detected E. testavorans in COSs of an adult male, subadult female, and juvenile male Blanding's turtle (0.6%; 95% confidence interval [CI], 0.2-1.9%) and a shell swab from an adult female RES (1.6%; 95% CI, 0-8.7%). Shell lesions consistent with E. testavorans infection were present in two of the positive Blanding's turtles. These results document the rarity of this pathogen on the landscape in Illinois. Additional studies should determine this pathogen's impact on individuals and clarify its significance for conservation efforts of Blanding's turtle, in which E. testavorans has not been reported previously.

Subcutaneous amikacin administration in red-eared sliders (Trachemys scripta elegans) produces prolonged detectable plasma concentrations without biochemistry evidence of impaired renal function.

OBJECTIVE: To establish pilot data on the plasma concentrations of SC amikacin at 2 doses in red-eared sliders and evaluate concurrent plasma biochemistry parameters. ANIMALS: 8 adult red-eared sliders (Trachemys scripta elegans). METHODS: Amikacin was administered SC at target doses of 5 and 10 mg/kg with a 3-week washout period. Blood samples were collected at 0, 24, 48, 72, and 96 hours postadministration. Plasma amikacin concentrations were quantified using liquid chromatography tandem mass spectrometry. Plasma biochemistry analyses were performed before amikacin administration, 1 week post 5-mg/kg administration, and 1 week post 10-mg/kg administration. RESULTS: Mean maximum amikacin plasma concentrations were recorded 24 hours after 5-mg/kg and 10-mg/kg dosing and were 17.5 ± 2.32 µg/mL and 23.6 ± 2.92 µg/mL, respectively. Mean plasma concentrations after 5-mg/kg dosing steadily decreased to 9.1 ± 0.92 µg/mL by 96 hours postadministration. Amikacin remained detectable in all plasma samples 3 weeks post 5-mg/kg dosing with a mean plasma concentration of 1.04 ± 0.22 µg/mL. Mean plasma concentrations after 10-mg/kg dosing did not decrease over the 96-hour study period. There were no clinically relevant changes in biochemistry parameters. CLINICAL RELEVANCE: Amikacin persists at detectable plasma levels for at least 3 weeks after SC administration of a 5-mg/kg dose in red-eared sliders, which has not previously been reported in any species. No biochemistry changes consistent with renal toxicity occurred after either dose. Use caution with repeated amikacin dosing in this species until further studies can better characterize cumulative amikacin pharmacokinetics and toxic threshold.

Development and analytical validation of a novel quantitative PCR assay for the detection of Trachemys herpesvirus 1.

Emerging infectious diseases are a threat that contributes to the decline of global chelonian species. Herpesviruses are among the most impactful pathogens described in chelonians and are frequently associated with a range of presentations across hosts with the potential for severe morbidity and mortality. Trachemys herpesvirus 1 (TrHV1) has been reported in red-eared and yellow-bellied sliders (Trachemys scripta elegans and Trachemys scripta scripta, respectively) but is largely understudied. Invasive red-eared sliders may serve as a reservoir for transmission to sympatric native species. This study aimed to develop a sensitive and specific quantitative real-time PCR (qPCR) assay for the detection of TrHV1 DNA to aid in the characterization of the epidemiology of this virus in aquatic turtles. Two TaqMan-MGB FAM-dye labeled primer-probe sets were designed and evaluated using plasmid dilutions. The higher performing assay was specific for TrHV1 DNA and had a linear dynamic range of 1.0 × 107 to 1.0 × 101 copies per reaction with an R2 of 0.999, slope of -3.386, and efficiency of 97.39%. The limit of detection was 101 copies per reaction, and there was no loss of reaction efficiency in the presence of TrHV1-negative chelonian oral-cloacal DNA. Overall, the Trachemys herpesvirus 1 assay meets established criteria for acceptable qPCR assays and will be a valuable tool in characterizing the epidemiology of Trachemys herpesvirus 1 in chelonians.

Subcutaneous administration of ceftazidime at 20 and 40 mg/kg produces theoretically therapeutic plasma concentrations for at least 120 hours in red-eared sliders (Trachemys scripta elegans).

OBJECTIVE: To evaluate and compare the pharmacokinetic parameters of SC ceftazidime administered at 20 and 40 mg/kg to red-eared sliders. ANIMALS: 8 adult red-eared sliders (Trachemys scripta elegans). METHODS: In a sequential, 2-period study with a 3-week washout period between treatments, ceftazidime was administered SC to turtles at 20 and 40 mg/kg. Blood samples were collected from the subcarapacial sinus at 0, 24, 48, 72, 96, and 120 hours after ceftazidime administration. Plasma ceftazidime concentrations were quantified using reversed-phase HPLC. RESULTS: Mean plasma half-life after 20- and 40-mg/kg dosing was 39.75 ± 8.0 hours and 33.03 ± 6.56 hours, respectively. Mean maximum plasma concentration after 20- and 40-mg/kg dosing was 71.0 ± 15.93 µg/mL and 120.0 ± 30.62 µg/mL, respectively. Mean plasma ceftazidime concentrations remained ≥ 8 µg/mL, the theoretical MIC for various reptile pathogens for all time points. CLINICAL RELEVANCE: Results indicate that ceftazidime dosed at either 20 or 40 mg/kg produces plasma concentrations exceeding the theoretical MIC of various reptile pathogens for at least 120 hours. An ideal dosing interval could not be determined, as all plasma concentrations remained above the threshold of interest for all time points. Follow-up studies should focus on establishing a dosing interval and more rigorous monitoring for potential adverse effects.

Angiotensin-(1-7) plays an important role in regulating spermatogenesis in Trachemys scripta elegans under salinity stress.

Elevation in water salinity can threaten the spermatogenesis and fertility of freshwater animals. The role of the renin-angiotensin system (RAS) in regulating spermatogenesis has attracted considerable attention. Our previous study found that red-eared sliders (Trachemys scripta elegans), could survive in 10 PSU water for over 1 year. To understand the chronic impact of salinity on testicular spermatogenesis and underlying mechanisms, male T. s. elegans were subjected to treatment with water of 5 PSU and 10 PSU for a year, and spermatogenesis and regulation of the RAS signal pathway was assessed. Results showed induced inflammation in the testes of T. s. elegans in the 10 PSU group, as evidenced by a decrease in the number of testicular germ cells from 1586 to 943. Compared with the control group, the levels of proinflammatory genes, including TNF-α, IL-12A and IL-6 were elevated 3.1, 0.3, and 1.4 times, respectively, in animals exposed to 10 PSU water. Testicular antiapoptotic processes of T. s. elegans might involve the vasoactive peptide angiotensin-(1-7) in the RAS, as its level was significantly increased from 220.2 ng ml-1 in controls to 419.2 ng ml-1 in the 10 PSU group. As expected, specific inhibitor (A-779) for the Ang-(1-7) acceptor effectively prevented the salinity-induced upregulation of genes encoding anti-inflammatory and antiapoptotic factors (TGF-ß1, Bcl-6) in the testis of the 10 PSU animals, whereas it promoted the upregulation of proinflammatory and proapoptotic factors (TNF-α, IL-12A, IL-6, Bax and caspase-3). Our data indicated that Ang-(1-7) attenuates the effect of salinity on inflammation and apoptosis of the testis in T. s. elegans. A new perspective to prevent salinity-induced testis dysfunction is provided.

Systemic Caryospora-like coccidiosis in a clutch of hatchling red-eared slider turtles (Trachemys scripta elegans).

Caryospora-like organisms (CLOs) form a clade of at least 11 genotypes of related coccidia that can cause epizootic mortality in marine turtles. The biology, transmission, host species range, and host cell tropism of these organisms are still largely unknown. The goal of this study was to characterize the host cell tropism, pathologic and ultrastructural features, and phylogeny associated with the first report of a mortality event due to CLO in the freshwater red-eared slider turtle (Trachemys scripta elegans). Sudden mortalities within a clutch of captive-raised red-eared slider hatchlings (n = 8) were recorded, and deceased animals had severe segmental to diffuse, transmural, fibrinonecrotic enterocolitis and multifocal to coalescing hepatic necrosis, among other lesions associated with numerous intracytoplasmic developing stages of intralesional coccidia. Among the different developmental stages, merozoites were ultrastructurally characterized by an apical complex. A pan-apicomplexan polymerase chain reaction (PCR) yielded a 347 bp-amplicon matching the Schellackia/Caryospora-like clade with 99.1% identity to the US3 strain from green sea turtles (Chelonia mydas) and 99.1% identity to Schellackia sp. Isolate OC116. Surviving hatchlings were treated with toltrazuril sulfone (ponazuril) but were subsequently euthanized due to the risk of spreading the parasite to other chelonids in the collection. The ponazuril-treated hatchlings (n = 4) had mild proliferative anterior enteritis, with few intraepithelial coccidia in one hatchling confirmed as CLO by PCR. This is the first report of Caryospora-like coccidiosis in non-cheloniid turtles, highlighting the relevance of this disease as an emerging highly pathogenic intestinal and extra-intestinal form of coccidiosis of turtles with potential cross-species infectivity.

Bacterial communities of the threatened Western Pond Turtle may be impacted by land use.

As semi-aquatic species that use both terrestrial and aquatic habitats, freshwater turtles and their microbial communities are especially sensitive to the impacts of habitat disturbance. In this study, we use 16S rRNA amplicon sequencing to characterize the shell and cloacal bacterial communities of turtles in the San Francisco Bay Area. We captured western pond turtles (Actinemys/Emys marmorata) across eight sites located in urban and rural environments, along with invasive red-eared sliders (Trachemys scripta elegans). We assessed differences in western pond turtle bacterial communities diversity/composition between shell and cloacal samples and evaluated how alpha/beta diversity metrics were influenced by habitat quality. We found phylum-level bacterial taxonomic turnover in the bacterial communities of western pond turtles relative to the host tissue substrate samples. Our findings indicate that location identity elicits a high degree of lower-level (i.e. species/genus) bacterial taxonomic turnover. Further, we found that samples originating from good quality habitat had poorer shell bacterial communities but more diverse cloacal ones. The shell bacterial communities of red-eared sliders overlapped with those western pond turtles suggesting the existence of microbial dispersal between these two species. Our results add to our current understanding of turtle symbiont microbial ecology by establishing patterns of bacterial symbiont variation in an urban to rural gradient.

Evidence for RA-dependent meiosis onset in a turtle embryo.

Meiotic entry is one of the earliest sex determination events of the germ cell in higher vertebrates. Although advances in meiosis onset have been achieved in mammals, birds and fish, how this process functions in reptiles is largely unknown. In this study, we present the molecular analysis of meiosis onset and the role of retinoic acid (RA) in this process in the red-eared slider turtle. Our results using Stra8 as a pre-meiosis indicator show that in the female embryonic gonad, meiosis commitment starts around stage 19. Additionally, signals of the meiosis marker Sycp3 could be detected at stage 19 and become highly expressed by stage 23. No expression of these genes was detected in male embryonic gonads, suggesting the entry into meiosis prophase I was restricted to female embryonic germ cells. Notably, RA activity in fetal gonads is likely to be elevated in females than that in males, as evidenced by the higher expression of RA synthase Aldh1a1 and lower expression of RA-degrading enzyme Cyp26a1 in female gonads prior to meiotic entry. In addition, exogenous RA treatment induced the expression of Stra8 and Sycp3 in both sexes, whether in vivo or in vitro. Together, these results indicate that high levels of RA in the embryonic female gonads can lead to the initiation of meiosis in the turtle.

Keep numbers in view: red-eared sliders (Trachemys scripta elegans) learn to discriminate relative quantities.

The ability to discriminate relative quantities, one of the numerical competences, is considered an adaptive trait in uncertain environments. Besides humans, previous studies have reported this capacity in several non-human primates and birds. Here, we test whether red-eared sliders (Trachemys scripta elegans) can discriminate different relative quantities. Subjects were first trained to distinguish different stimuli with food reward. Then, they were tested with novel stimulus pairs to demonstrate how they distinguished the stimuli. The results show that most subjects can complete the initial training and use relative quantity rather than absolute quantity to make choices during the testing phase. This study provides behavioural evidence of relative quantity discrimination in a reptile species and suggests that such capacity may be widespread among vertebrates.

Comparison of intramuscular alfaxalone with medetomidine-ketamine for inducing anaesthesia in Trachemys scripta spp. undergoing sterilization.

OBJECTIVE: To compare the effect of two anaesthetic protocols on heart rate (HR), time to muscle relaxation and tracheal intubation and time to surgical plane of anaesthesia, in Trachemys scripta spp. undergoing oophorectomy. STUDY DESIGN: Prospective randomized clinical study. ANIMALS: A total of 43 healthy female turtles. METHODS: Morphine (1.5 mg kg-1) was injected subcutaneously 2 hours before anaesthesia induction. The turtles were randomly administered either medetomidine (0.2 mg kg-1) and ketamine (10 mg kg-1) (group MK; n = 23) or alfaxalone (20 mg kg-1) (group A; n = 20) intramuscularly followed by bupivacaine (2 mg kg-1) administered subcutaneously along the incision site. Anaesthesia was maintained with isoflurane delivered in oxygen (100%). HR and the anaesthetic depth score (ADS) were recorded every 5 minutes from induction to recovery. A Friedman test followed by Wilcoxon tests with Bonferroni adjustment were used to compare these non-parametric data (HR and ADS) between groups and over time. Time to muscle relaxation of neck and limbs (TMR), tracheal tube insertion (TTTI) and stage of surgical anaesthesia (TADS≤3) were recorded and compared between groups using a Welch's t test after logarithmic transformation. RESULTS: Median values of TMR, TTTI and TADS≤3 were 4, 9.5 and 25 minutes in group A, respectively, and 14, 20 and 35 minutes in group MK (TMR, TTTIp ≤ 0.0001; TADS≤3p = 0.001). Plane of anaesthesia was significantly deeper in group A than in group MK for the first 20 minutes (p < 0.01). HR at 10 and 15 minutes post injection was significantly lower in group MK (28 beats minute-1) than in group A (36 and 34 beats minute-1) (p < 0.02). CONCLUSIONS AND CLINICAL RELEVANCE: After intramuscular injection in Trachemys scripta spp., tracheal intubation, muscle relaxation and a surgical plane of anaesthesia developed faster with alfaxalone than medetomidine-ketamine.

Quantum Mechanics/Molecular mechanics calculations predict A1, not A2, is present in melanopsin (Opn4m) of red-eared slider turtles (Trachemys scripta elegans).

Melanopsin is a photopigment that plays a role in non-visual, light-driven, cellular processes such as modulation of circadian rhythms, retinal vascular development, and the pupillary light reflex (PLR). In this study, computational methods were used to understand which chromophore is harbored by melanopsin in red-eared slider turtles (Trachemys scripta elegans). In mammals, the vitamin A derivative 11-cis-retinal (A1) is the chromophore, which provides functionality for melanopsin. However, in red-eared slider turtles, a member of the reptilian class, the identity of the chromophore remains unclear. Red-eared slider turtles, similar to other freshwater vertebrates, possess visual pigments that harbor a different vitamin A derivative, 11-cis-3,4-didehydroretinal (A2), making their pigments more sensitive to red-light than blue-light, therefore, suggesting the chromophore to be the A2 derivative instead of the A1. To help resolve the chromophore identity, in this work, computational homology models of melanopsin in red-eared slider turtles were first constructed. Next, quantum mechanics/molecular mechanics (QM/MM) calculations were carried out to compare how A1 and A2 derivatives bind to melanopsin. Time dependent density functional theory (TDDFT) calculations were then used to determine the excitation energy of the pigments. Lastly, calculated excitation energies were compared to experimental spectral sensitivity data from responses by the irises of red-eared sliders. Contrary to what was expected, our results suggest that melanopsin in red-eared slider turtles is more likely to harbor the A1 chromophore than the A2. Furthermore, a glutamine (Q622.56) and tyrosine (Y853.28) residue in the chromophore binding pocket are shown to play a role in the spectral tuning of the chromophore.

Effect of Impact Angle on the Impact Mechanical Properties of Bionic Foamed Silicone Rubber Sandwich Structure.

In this paper, a red-eared slider turtle is used as the prototype for the bionic design of the foamed silicone rubber sandwich structure. The effect of impact angle on the performance of the foamed silicone rubber sandwich structure against low-velocity impact is studied by the finite element method. The numerical model uses the intrinsic structure model of foamed silicone rubber with porosity and the three-dimensional Hashin fiberboard damage model. The validity of the model was verified after experimental comparison. Based on the finite element simulation of different impact angles and velocities, the relationship between impact velocity and residual velocity, as well as the penetration threshold at various impact angles are obtained, and the change law of impact resistance of foamed silicone rubber sandwich structure with impact angle and velocity, as well as the damage pattern of sandwich structure at different impact angles and velocities are given. The results can provide a basis for the impact resistance design of the bionic foamed silicone rubber sandwich structure. The results show that, at a certain impact speed, the smaller the impact angle, the longer the path of the falling hammer along the plane of the sandwich structure, the lighter the damage to the sandwich structure and the greater the absorbed energy, so that avoiding the impact from the frontal side of the sandwich structure can effectively reduce the damage of the sandwich structure. When the impact angle is greater than 75°, the difference in impact resistance performance is only 2.9% compared with 90°, and the impact angle has less influence on the impact resistance performance at this time.

Indirect evidence that anoxia exposure and cold acclimation alter transarcolemmal Ca2+ flux in the cardiac pacemaker, right atrium and ventricle of the red-eared slider turtle (Trachemys scripta).

We indirectly assessed if altered transarcolemmal Ca2+ flux accompanies the decreased cardiac activity displayed by Trachemys scripta with anoxia exposure and cold acclimation. Turtles were first acclimated to 21 °C or 5 °C and held under normoxic (21N; 5N) or anoxic conditions (21A; 5A). We then compared the response of intrinsic heart rate (fH) and maximal developed force of spontaneously contracting right atria (Fmax,RA), and maximal developed force of isometrically-contracting ventricular strips (Fmax,V), to Ni2+ (0.1-10 mM), which respectively blocks T-type Ca2+ channels, L-type Ca2+ channels and the Na+-Ca2+-exchanger at the low, intermediate and high concentrations employed. Dose-response curves were established in simulated in vivo normoxic (Sim Norm) or simulated in vivo anoxic extracellular conditions (Sim Anx; 21A and 5A preparations). Ni2+ decreased intrinsic fH, Fmax,RA and Fmax,V of 21N tissues in a concentration-dependent manner, but the responses were blunted in 21A tissues in Sim Norm. Similarly, dose-response curves for Fmax,RA and Fmax,V of 5N tissues were right-shifted, whereas anoxia exposure at 5 °C did not further alter the responses. The influence of Sim Anx was acclimation temperature-, cardiac chamber- and contractile parameter-dependent. Combined, the findings suggest that: (1) reduced transarcolemmal Ca2+ flux in the cardiac pacemaker is a potential mechanism underlying the slowed intrinsic fH of anoxic turtles at 21 °C, but not 5 °C, (2) a downregulation of transarcolemmal Ca2+ flux may aid cardiac anoxia survival at 21 °C and prime the turtle myocardium for winter anoxia and (3) confirm that altered extracellular conditions with anoxia exposure can modify turtle cardiac transarcolemmal Ca2+ flux.

Endoplasmic reticulum unfolded protein response modulates the adaptation of Trachemys scripta elegans in salinity water.

Trachemys scripta elegans, as a freshwater invasive species, can survive and lay eggs in brackish water, which may lead to the expansion of its potential invasion range due to freshwater salinization. Our previous studies have shown that high salinity leads to the accumulation of serum lipid content, which may induce endoplasmic reticulum stress (ERS) in the turtle. To better understand whether ERS is triggered by salinity, and in turn whether the turtles promote the protection mechanism, we exposed the turtles to the freshwater (CK), 5‰ salinity water (S5) and 15‰ salinity water (S15), and sampled at 6 h, 24 h and 30 d. 13 differentially expressed genes (DEGs) related to ERS pathways were found in the comparison of CK vs. S15 by transcriptomics analysis. Then, the mRNA and protein expression of ERS and its related activation pathways were further investigated. ERS marker glucose regulated protein 78 kD (GRP78) increased significantly (p < 0.05) in both the transcript and protein levels after exposure to 15‰ salinity water, which clearly indicated that salinity could induce ERS in T. s. elegans. Meanwhile, the three unfolded protein response (UPR) including transducers protein kinase RNA (PKR)-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1α (IRE1α) and activating transcription factor-6 (ATF6) were promoted by salinity, suggesting that the turtle might promote physiological process to eliminate damaged cells and cope with unfolded proteins accumulation induced by ERS. Our results provide new insight into the mechanism of salinity adaptation in T. s. elegans and salt-tolerant biological invasion.

Trichinella pseudospiralis infection in red-eared slider, Trachemys scripta, influenced by environmental temperature.

Experimental infection with Trichinella pseudospiralis larvae in red-eared slider Trachemys scripta was carried out. Ten turtles were divided into 3 groups and kept at different temperature (38, 32 and 28 °C). The turtles were fed mice muscles which were infected with T. pseudospiralis larvae (444 - 23,013 larvae/mouse), kept in the aforementioned temperature and necropsied at day 30 after infection. At necropsy, the tongue, forelimbs, hindlimbs and spinal column muscles of turtles were removed separately for pepsin digestion, and the larvae counted. Larvae were found from all 3 turtles kept at 38 °C. Larvae per gram of muscle were highest in the tongue. No larvae were recovered from turtles kept at 32 and 28 °C. The result suggested that T. pseudospiralis is able to infect the red-eared slider in a high temperature environment. We speculated that environmental temperature play an important role in altering the physiological condition of the turtle to facilitate the infection of T. pseudospiralis.

Evaluation of the effects of two anaesthetic protocols on oxidative status and DNA damage in red-eared sliders (Trachemys scripta elegans) undergoing endoscopic coeliotomy.

The aim of this study was to assess how red-eared sliders (Trachemys scripta elegans) respond to anaesthesia itself and coelioscopy. For that purpose, the turtles were anaesthetised with ketamine-medetomidine or propofol, and the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the level of malondialdehyde (MDA) were determined by spectrophotometry. The possible genotoxic effects of the anaesthetic agents were estimated by comet assay. A total of 24 turtles were included in this study. The animals were divided into four groups according to the anaesthetic protocol and according to whether endoscopy would be performed. Significantly decreased activities of CAT were found only in the propofol group and in turtles undergoing coelioscopy. Both anaesthetic protocols induced significantly increased MDA levels, while no differences were observed after the intervention. A significant increase in GST activity was detected in turtles after both anaesthetic protocols, but after coelioscopy significant changes in GST activity were found only in the propofol group. However, no differences in SOD activity and no DNA damages were detected in either group. These findings suggest that ketamine-medetomidine may be more suitable anaesthetic agents in red-eared sliders than propofol.

On some structural and evolutionary aspects of rDNA amplification in oogenesis of Trachemys scripta turtles.

The features of rDNA amplification have been studied in oocytes of the red-eared slider Trachemys scripta using a number of specific histochemical and cytomolecular methods. A single nucleolus in early diplotene oocytes is associated with the nucleolus organizer region (NOR). With oocyte growth, the number of nucleoli increases dramatically and reaches hundreds by the lampbrush chromosome stage (pre-vitellogenesis). RNA-polymerase I, fibrillarin, and PCNA immunodetection in the amplified nucleoli and FISH of the 5'ETS probe to the oocyte nuclear content suggest pre-rRNA and rDNA synthesis in the nucleoli at all stages studied. This implies a continuous reproduction of the nucleoli during oocyte development from early diplotene up to vitellogenesis. The data obtained offer a different way for rDNA amplification and formation of extrachromosomal nucleoli in turtle oocytes compared with the amplified nucleoli formation in amphibian and fish oocytes. In the Sauropsida clade of Archelosauria, which includes turtles, crocodiles, and birds, rDNA function is known to be suppressed in avian oogenesis during the lampbrush stage (Gaginskaya et al. in Cytogenet Genome Res 124:251-267, 2009).

TEMPORAL STABILITY OF IN VITRO VENOUS BLOOD GAS, pH, AND LACTATE VALUES OF COWNOSE RAYS (RHINOPTERA BONASUS) AND RED-EARED SLIDER TURTLES (PSEUDEMYS SCRIPTA ELEGANS).

This study assessed the in vitro temporal changes that occur in blood pH and lactate concentrations for an elasmobranch species and a chelonian species, as well as blood gases (partial pressures of carbon dioxide [pCO2] and oxygen [pO2]) for a chelonian species, with a portable clinical point-of-care analyzer. Blood samples were collected from 10 cownose rays (Rhinoptera bonasus) and 10 red-eared sliders (Pseudemys scripta elegans), stored on ice, and serially analyzed at six time points up to 90 min postcollection. Results indicate that analysis should be conducted as soon as possible after blood collection for these species, with immediate analysis being preferred. However, if analysis must be delayed, syringes may be capped, placed on ice, and analyzed at a later time. Analysis within 90 min provided clinically acceptable results for pH and lactate in both species and for pCO2 in red-eared sliders, whereas substantial artifactual increases of pO2 were seen in red-eared sliders.

Detection of Cryptosporidium parvum in a Red-Eared Slider Turtle (Trachemys scripta elegans), a Noted Invasive Alien Species, Captured in a Rural Aquatic Ecosystem in Eastern Poland.

PURPOSE: Little is known about cryptosporidiosis in turtles of invasive alien species (IAS) inhabiting European bodies of fresh water. In this article, we report an occurrence of Cryptosporidium parvum in a red-eared slider turtle (Trachemys scripta elegans) captured in a rural aquatic ecosystem in eastern Poland. METHODS: A pair of samples consisting of feces and scrapings of intestinal mucosa (taken during necropsy) were collected from 104 animals representing the four IAS turtle species red-eared slider, yellow-bellied slider, false map and Cumberland slider. The animals were trapped in running and standing freshwater ecosystems across the Lublin province. Parasite genomic DNA was extracted from samples using a modified alkali wash and a heat-lysis method and identification of the Cryptosporidium species was performed at the 18SSU rRNA and COWP loci. RESULTS: The presence of Cryptosporidium DNA was only detected in one sample of intestinal scraping collected from a red-eared slider. A phylogenetic analysis of a 18SSU rRNA gene fragment showed 100% sequence identity between the C. parvum strain isolated from the turtle and other C. parvum strains previously detected in cattle from the Lublin province. CONCLUSIONS: There was no clinical evidence that the red-eared slider turtle was truly infected rather than being merely a mechanical parasite carrier. Sporadic detection of this protozoan parasite in the studied population of IAS turtles could be associated with low natural occurrence of Cryptosporidium infections in this animal species. The results provide evidence for possible transmission of zoonotic Cryptosporidium species by IAS turtles.