Red-eared Slider Trachemys Scripta Research Articles

Morphological and transcriptomic analyses of embryonic development of red-eared slider Trachemys scripta elegans

Embryology provides an understanding of individual’s origin and developmental patterns. Turtles are among the oldest living reptiles and have unique body structure. However, the morphogenesis and mechanisms of turtles are not fully understood. In this study, we focused on the embryonic development of red-eared slider (Trachemys scripta elegans) which widely distributes in the world. At an incubation temperature of 28 °C, the turtle eggs had a 61-day incubation cycle, and the entire embryonic development process was divided into 27 stages and 3 phases according to variations in age, body size, and morphological characteristics. The early phase of embryonic development (the first 12 stages) were characterized by embryo growth, and the appearance of internal organ precursors. The middle phase (stages 13–20) involved prominent heart division at stage 13 and the appearance of carapace and plastron at stages 14 and 17, respectively. In the later phase (stages 21–27), the hatchlings formed, and the carapace and plastron thickened. Transcriptome analysis of embryos showed enrichment of the differential genes in pathways related to development, metabolism, disease, and cellular processes. The Kyoto Encyclopedia of Genes and Genomes enrichment (KEGG) analysis implied the crucial regulatory role of the axon guidance pathway. Real-time fluorescence quantitative PCR indicated upregulated expression of wnt5a and bmp7 in stages 7 and 16 compared to that in stage 12. This study revealed the development process of red-eared slider embryo and the dynamics of the signaling pathway affecting its development, which supplemented the theory of embryo development, and provided new ideas for the molecular mechanism of turtle embryo development.

Coexistence of Native and Invasive Freshwater Turtles: The Llobregat Delta (NE Iberian Peninsula) as a Case Study

The global degradation of wetlands is increasing their susceptibility to invasions, which is greatly determined by a niche overlap between native and invasive species. We analyze its role in regulating the coexistence of the native Mediterranean stripe-necked terrapin Mauremys leprosa and the invasive Red-eared Slider Trachemys scripta elegans in a coastal wetland. We analyzed both water chemistry and landscape attributes, using variance-partitioning analysis to isolate the variance explained by each set of variables. Then, the influence of environmental variables on species co-occurrence patterns was assessed by using latent variable models (LVM), which account for correlation between species that may be attributable to biotic interactions or missing environmental covariates. The species showed a very low niche overlap, with clear differences in their response to environmental and landscape filters. The distribution of T. s. elegans was largely explained by landscape variables, preferring uniform landscapes within the daily movement buffer, whereas at larger scales, it was associated with a high diversity of habitats of small and uniform relative sizes. A high percentage of the distribution of M. leprosa was unexplained by the measured variables and may be related to the competitive exclusion processes with T. s. elegans. The species was positively related with large patches with high perimeter values or ecotone area at medium spatial scales, and it was benefited from a marked heterogeneity in the patches’ size at larger scale. According to latent variable models, both species had wide eutrophication and salinity tolerance ranges, but they showed different environmental preferences. T. s. elegans was related to eutrophic freshwater environments, whereas M. leprosa was related to more saline and less eutrophic waters. Our results suggest that M. leprosa modifies its habitat use in order to avoid interaction with the T. s. elegans. Thus, management actions aimed at removing the invasive species from the territory and promoting habitat heterogeneity might be needed to protect M. leprosa and avoid local extinctions.

Feasibility, Gross Postmortem Results and Participant Perception of Oblique Prefemoral Ovariectomy in Red Eared Sliders (Trachemys scripta elegans) During a Teaching Workshop

The purpose of the present report is to describe feasibility and gross postmortem results of oblique prefemoral ovariectomy in red-eared sliders (Trachemys scripta elegans) performed by veterinarians in a teaching environment. Sixteen red-eared sliders were included in a teaching workshop. The turtles were anesthetized and placed in dorsolateral recumbency at an oblique 45-degree angle by use of folded towels. After prefemoral access to the celom and placement of a retractor with elastic bands, the ipsilateral follicles were exteriorized via gentle maneuvering with cotton tip applicators and excised after application of titanium clips and cautery with bipolar radiosurgery. On 14 of the 16 chelonians (87.5%) surgery was successfully completed. Of the two chelonians that did not have the surgical procedure completed, one had marked celomitis with adhesion of the ovaries to the liver and one had immature ovaries. At the end of the surgical procedures all chelonians were euthanized and postmortem was performed. The 14 chelonians that had surgery completed had no evident remaining ovarian tissue on gross postmortem. A survey completed by the attendants nine months after the workshop showed that a minority of the respondents (1/17) found the procedure difficult, and that one of the seven respondents that performed the surgery after the workshop was not able to complete the procedure. This report indicated that oblique prefemoral ovariectomy in mature red-eared sliders can be effectively taught to veterinarians during a workshop, and that if the procedure is completed the chances of leaving ovarian remnants are low.

Online and pet stores as sources of trade for reptiles in South Africa

The ever-increasing human population, globalisation, and desire to keep pets have resulted in the translocation of many species into non-native environments. As a result, some of the non-native reptile species have been introduced to South Africa through the pet trade. However, little is known about the extent of trade in reptiles via online and physical pet stores in South Africa and their potential climatically suitable areas. We assessed the physical pet store and online trade of reptiles in South Africa. We found 69 physical pet stores and 18 online advertising websites selling 1,912 individuals of 66 species and 859 individuals of 50 reptile species, respectively. In total, we found 88 unique species representing 18 families from both sources, of which 86.4% were non-native species and 32 species were CITES-listed. Snakes were the most dominant (76.1%) traded group. Ball python Python regius (n = 601), corn snake Pantherophis guttatus (n = 553) and central bearded dragon Pogona vitticeps (n = 419) were the most-traded reptiles. Prices ranged from ZAR100.00 to ZAR6,000.00, with sharp-nosed viper Deinagkistrodon acutus acutus being the most expensive species. For present distributions, the red-eared slider Trachemys scripta elegans, P. guttatus, and Western diamondback rattlesnake Crotalus atrox had the largest predicted climatic suitability. The future predictions for the latter two species were predicted to increase while red-eared slider suitability shifted. Most popular species were available in large volumes, sold at relatively low prices and had high climatic suitability, representing a high potential invasion risk. We, therefore, propose that the existing pet trade regulations should be revised to include a more restricted trade on the trade of endangered, non-CITES listed and potential invasive pet species.

Range expansion of the alien red-eared slider Trachemys scripta (Thunberg in Schoepff, 1792) (Reptilia, Testudines) in Eastern Europe, with special reference to Latvia and Ukraine

Range expansion of the alien red-eared slider Trachemys scripta (Thunberg in Schoepff, 1792) (Reptilia, Testudines) in Eastern Europe, with special reference to Latvia and Ukraine

Biomimetic approaches towards lightweight composite structures for car interior parts

Due to good density specific mechanical properties and low carbon footprint, natural fibre-reinforced plastic composites made from fleeces and felts are frequently used as automotive interior parts. The industry targets further mass reduction. Following a biomimetic technology-pull approach, natural fibre-reinforced polypropylene plates with improved lightweight potential were produced using compression moulding. Best results were obtained for a sandwich structure with thin, unidirectional flax fibre layers surrounding a needle felt based core. It was inspired by the carapace structure of the red-eared slider Trachemys scripta elegans. The lay-up performed well, not only with a high density specific flexural stiffness of 2.33GPa1/3 cm3/g, strength of 9.46 MPa1/2 cm3/g, and energy dissipation but also through less abrupt failure due to an asymmetric orientation of unidirectional fibres in the two face sheets. Combined with a mass-reduced needle felt as a core, this concept displays a promising and unconventional approach for further mass reduced, sustainable interior panels used as non-visible and visible design elements in the vehicle.

Trichinella pseudospiralisinfectionin 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.

Intestinal Intussusception Associated with Cloacal Protusion in Trachemys scripta elegans

Background: Gastrointestinal dysfunction in reptiles is a common condition seen in animal medicine, and is often caused by inappropriate husbandry. The purpose of this report is to describe the case of a surgical procedure for enterectomy of the small intestines, performed as treatment for an intussusception with cloacal protrusion that occurred in a red-eared slider (Trachemys scripta elegans) kept as a pet.Case: A 20-year-old red-eared slider (Trachemys scripta elegans) was taken into medical care after the owner’s observation of a cloacal protrusion that had started 72 h previously. During physical examination the protrusion was noted as an intestinal segment of approximately 5 cm, which was not reducible. Complementary examinations, including radiography and hematological profiling, were performed and revealed no significant findings; therefore, it was decided that an exploratory celiotomy would be conducted. The patient was referred to the surgical unit for the procedure and underwent surgical anesthesia. After appropriate antisepsis of the surgical area, a plastron osteotomy was performed using a previously sterilized oscillatory saw at a 45º angulation. The celomatic membrane was subsequently incised to enable both cavity and intestinal inspection allowing observation of the intussusception in the small intestine of the animal with the intussuscept segment protruding through the cloaca. The intussusception was undone, and an enterectomy was performed to remove the unviable intestine, using intestinal resection and subsequent anastomosis with simple interrupted sutures using 4-0 nylon, followed by intestinal reposition in the cavity. The celomatic membrane was closed using continuous suture with 4-0 nylon. The plastron fragment was then repositioned with the aid of eight cerclage fixations using 2-0 stainless steel wire. It was subsequently covered in self-polymerizing resin acrylic in order to promote impermeability and to protect the surgical wound. During the recovery period, supportive treatment and analgesia and antibiotic therapy were performed. The patient’s first defecation was observed five days after the procedure, and gastrointestinal tract functions returned to normal after four weeks. In six weeks, the patient was discharged.Discussion: In this case, exploratory celiotomy was performed due to the extension of the necrotic areas of the protruded mucosa. Plastron osteotomy is generally indicated because of the possibility of wide organ exposure. During the long healing period of reptiles, a surgical wound can be a gateway for pathogens that lead to postoperative surgical complications. As such, the use of acrylic resin in the present case was to create a protective barrier that would offer more resistance and impermeability. End-to-end enterectomy, in this instance, proved to be an efficient treatment for the small intestines cloacal protrusion, just as it was for the intussusception that preceded it. The probable cause of this case of intussusception was not well defined, and reptiles kept as pets have several diseases that can affect the gastrointestinal tract. The environment temperature also strongly influences gastrointestinal tract functions, which can lead to motility decline and imbalance of the intestinal flora, followed by the production of gases and toxins by microorganisms responsible for dysfunctions. Inadequate temperature management was the suspected main cause of intussusception in this case, as the patient was kept without access to sunlight or a heating source. In conclusion, the enterectomy with subsequent anastomosis that we performed was successful in the treatment of cloacal protruded intussusception of the small intestines in this red-eared slider (Trachemys scripta elegans).

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 nucleolusorganizer 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).

Red-eared Sliders Trachemys scripta elegans in southern Sydney, including new incursions

The invasive Red-eared Slider Trachemys scripta elegans has spread extensively, forming naturalised populations on all continents except Antarctica. Ranked among the 100 worst invasive species, there are biosecurity concerns that native turtles become outcompeted and displaced, as well as other speculative impacts. The actual ecological impacts in Australia have not been properly studied, however impacts shown in other countries are concerning. Incursions have presented in New South Wales, Queensland, Victoria, Western Australia and the Australian Capital Territory. A number of sightings have been reported from southern Sydney, including six sites where more than one slider has persisted. The incursions at Yeramba Lagoon in the Georges River National Park and the Centennial Parklands have been the most documented, whereas incursions in the Lime Kiln Bay Wetland, Rockdale Wetlands Corridor and Audley in the Royal National Park appear to have occurred recently. To date, breeding in southern Sydney has only been confirmed at Yeramba Lagoon. A range of removal techniques have been successfully applied to eradicate isolated incursions in Brisbane and Melbourne. However, these options are difficult to implement in southern Sydney sites where incursions occur in high visitation public lands.

<b>Diversity and distribution of freshwater turtles (Reptilia: Testudines) in Goa, India</b>

Freshwater turtles symbolize a key component of biodiversity in aquatic ecosystems. Of the 356 living species of turtles and tortoises in the world, 34 species are recorded from India. The number of freshwater turtle and tortoise species found in the state of Goa, however, is debatable. No study specific to the Goa region has been carried out on freshwater turtles. Therefore, baseline data on diversity and distribution of freshwater turtles is scanty. The present study was conducted to address this lacuna in knowledge, which will further aid in identifying threats to the population of freshwater turtles and in devising appropriate methods for their conservation. The diversity and distribution of freshwater turtles was investigated in 186 sites in Goa from June 2012 to May 2015. A total of 337 specimens of two native and one introduced species of freshwater turtles belonging to three families—Trionychidae (Indian Flap-shell Turtle Lissemys puncata), Geomydidae (Indian Black Turtle Melanochelys trijuga) and Emydidae (Red-eared Slider Trachemys scripta elegans)— were identified. Melanochelys trijuga (52.23%) was the most widely and abundantly distributed species, and was recorded from 132 sites. L. punctata (46.88%) was recorded from 113 sites, while T. scripta elegans (0.89%) was rare and was recorded from only two sites. While Melanochelys trijuga is generalized in habitat selection, making it the widely distributed species in the State of Goa, L. punctata is more specific in habitat selection thus restricting its range to coastal, middle-level plateau and the foothills of Western Ghats.

Rozmieszczenie stanowisk inwazyjnego żółwia czerwonolicego (Trachemys scripta elegans) (Wied, 1838) w województwie zachodniopomorskim (północno-zachodnia Polska)

Rozmieszczenie stanowisk inwazyjnego żółwia czerwonolicego (Trachemys scripta elegans) (Wied, 1838) w województwie zachodniopomorskim (północno-zachodnia Polska)

Distribution and Status of the Alien Invasive Red-eared Slider (Trachemys scripta elegans) in Jeju Island, South Korea

Distribution and Status of the Alien Invasive Red-eared Slider (Trachemys scripta elegans) in Jeju Island, South Korea

Introduction and invasion of the red-eared slider and its parasites in freshwater ecosystems of Southern Europe: risk assessment for the European pond turtle in wild environments

The North American red-eared slider Trachemys scripta elegans, which is nowadays considered among the world’s worst invasive species, could constitute a real threat to native freshwater turtles. Because this species shares the same habitats of the European pond turtle Emys orbicularis since its introduction in the European wetlands, we surveyed populations of both alien and indigenous species in France and Spain in order to determine the diversity of platyhelminth parasites (Monogenea, Polystomatidae) in natural environments and to evaluate the levels of risks associated with parasitism. DNA barcoding procedure based on partial cytochrome c oxydase I sequences revealed ten monogenean parasite species within E. orbicularis populations and/or captive animals among which at least eight could be considered as introduced parasites from American freshwater turtles. Results indicated that host switching could have occurred either in natural environments or in captivity, when indigenous turtles were kept with exotic species, demonstrating that captive turtles could act as reservoirs of parasites. The presence of non-native parasite species within wild populations of E. orbicularis in the European freshwater ecosystems also highlighted the risks that these parasites may pose on the survival of natural turtle’s populations and on the dynamics of native parasites.

Host Associations ofHelobdella octatestisaca(Hirudinida: Glossiphoniidae) and the First Report of this Leech in the United States

ABSTRACT: Helobdella octatestisaca Lai and Chang, 2009, was originally described from Taiwan where it is believed to have been introduced. It has subsequently been reported from throughout much of Mexico. Helobdella octatestisaca was collected from a small pond in Walker County, Texas, U.S.A., representing the first report of this species from the United States. Helobdella octatestisaca occurred primarily associated with red-eared slider turtles, Trachemys scripta, and common mud turtles, Kinosternon subrubrum. Individuals of H. octatestisaca were frequently found within clusters of juveniles of the common turtle leech, Placobdella parasitica, and were often attached to individuals of P. parasitica. It was hypothesized that H. octatestisaca is utilizing P. parasitica as a source of food and that Helobdella spp. preferentially associate with turtles, thereby gaining enhanced access to prey items.

The high resolution melting analysis (HRM) as a molecular tool for monitoring parasites of the wildlife.

In an interconnected world, the international pet trade on wild animals is becoming increasingly important. As a consequence, non-native parasite species are introduced, which affect the health of wildlife and contribute to the loss of biodiversity. Because the investigation of parasite diversity within vulnerable host species implies the molecular identification of large samples of parasite eggs, the sequencing of DNA barcodes is time-consuming and costly. Thereby, the objectives of our study were to apply the high resolution melting (HRM) approach for species determination from pools of parasite eggs. Molecular assays were validated on flatworm parasites (polystomes) infecting the Mediterranean pond turtle Mauremys leprosa and the invasive red-eared slider Trachemys scripta elegans in French natural environments. HRM analysis results indicated that double or multiple parasitic infections could be detected from wild animal populations. They also showed that the cycle of parasite eggs production was not regular over time and may depend on several factors, among which the ecological niche and the target species. Thereby, monitoring parasites from wild endangered animals implies periodic parasitological surveys to avoid false negative diagnostics, based solely on eggs production.

Helminth fauna of the invasive American red-eared slider Trachemys scripta in eastern Spain: potential implications for the conservation of native terrapins

In this study we report on the helminth fauna of the invasive American red-eared slider Trachemys scripta in five localities from eastern Spain where this species co-occurs with two native, endangered freshwater turtles, i.e. Emys orbicularis and Mauremys leprosa. In total, 46 individuals of T. scripta were analysed for parasites. Adult individuals of three helminth species were found: the monogenean Neopolystoma orbiculare, the digenean Telorchis solivagus and the nematode Serpinema microcephalus. Telorchis solivagus and S. microcephalus are trophically transmitted parasites of native turtles that probably infected T. scripta through shared infected prey. Neopolystoma orbiculare infects T. scripta in its native Nearctic range and probably survived the overseas shipping of hosts due to the combination of a direct life cycle, long lifespan in turtles and crowding conditions that allowed frequent (re)infections. These findings entail potentially significant conservation consequences that deserve further attention. First, there was a successful spill-back of Telorchis solivagus and S. microcephalus to large invasive populations of T. scripta in the study area, which could eventually increase infection levels in native turtles. Second, the possibility of spill-over of N. orbiculare to native turtles should not be underestimated as this phenomenon has recently been reported in France. Given the pathogenic potential of N. orbiculare, its transference to native turtles could be troublesome.

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 sequence divergence of the mt-genome (p distance) between scripta and elegans was 0.4%. A detailed comparison between the mitochondrial genomes of the two subspecies is shown.

Corticosterone Levels during the Nesting Process in Red-eared Sliders (Trachemys scripta)

Abstract Free-living vertebrates tend to respond to environmental challenges by increasing circulating glucocorticoid levels. Changes in glucocorticoids can modulate various aspects of physiology and behavior, which can have fitness benefits in the short term but may be detrimental to fitness if elevated levels are frequent, prolonged, or both. The transfer of glucocorticoids from females to offspring might also have fitness consequences, but there is less known about the potential effects of transgenerational glucocorticoid transfer. Our study examined corticosterone levels in female Red-eared Sliders (Trachemys scripta) during the nesting season because of the potential fitness consequences for both females and offspring. Whether caught in aquatic traps or caught during the nesting process, females had similar circulating corticosterone levels that were relatively low. However, when females were subjected to a restraint protocol, corticosterone rose. Therefore, corticosterone levels may be elevated duri...

Reproductive demography of two closely related Emydine Turtles in a spring fed system

Freshwater turtles are appropriate organisms for studying maternal investment in offspring because, unlike most long-lived vertebrates, turtles show high fecundities and most provide no parental care. We studied reproductive patterns of two emydine freshwater turtle species, the Texas river cooter (Pseudemys texana) and the red-eared slider (Trachemys scripta elegans) at Spring Lake, Hays County, Texas during the 2009 nesting season. Forty-six percent of all nesting Texas river cooters and 25% of all nesting red-eared sliders nested twice, with some Texas river cooters nesting more than twice. Mean egg mass, egg length, and egg width decreased in subsequent clutches in Texas river cooters. However, there was an insufficient sample size of subsequent clutches (n = 6) to draw conclusions for red-eared sliders. Red-eared sliders did not show a positive relationship between clutch size and body size. We found that in both species there was a positive relationship between egg width and egg mass in relation to maternal body size. However, only Texas river cooters showed a positive relationship between clutch size and maternal size, while only red-eared sliders showed a positive relationship between egg length and maternal size. By comparing reproductive parameters of these two coexisting populations, we concluded that the members of these two species allocate resources differently for reproduction.