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PubMed2004

Metastatic squamous cell carcinoma in two loggerhead sea turtles Caretta caretta.

We received 2 stranded loggerhead sea turtles (Caretta caretta) with squamous cell carcinomas to necropsy. The dead turtles had been collected in Gran Canaria and Fuerteventura in April 1994 and May 1997, respectively to determine the cause of death. One turtle had 3 ulcerated lesions in the dorsal part of the neck and several irregular masses in the lungs and kidneys. Histologic examination of lesions in the skin, lungs, kidneys, and ventricular myocardium revealed neoplastic proliferation of abnormal keratinocytes. Ultrastructural examination identified the tumoral cells as epithelial cells. The second turtle had 4 lesions in the skin of the head and flippers, and several irregular masses in the lungs, liver, and kidneys. Histological examination revealed a squamous cell carcinoma with metastases to muscle tissue, liver, lungs, and kidneys. Attempts to characterize the tumoral cells by immunohistochemistry using several monoclonal and polyclonal antisera against high and low molecular weight cytokeratins from mammals, as well as vimentin and desmin, failed. Differences between reptilian keratins (mainly beta-keratins) and mammalian keratins (mainly alpha-keratins) could explain this absence of immunoreactivity. This is the first description of squamous cell carcinoma in sea turtles.

Animals↗
PubMed2005

Myxidium mackiei (Myxosporea) in Indo-Gangetic flap-shelled turtles Lissemys punctata andersonii: parasite-host interaction and ultrastructure.

Myxosporeans are common parasites of fish, and uncommon parasites of amphibians, reptiles and invertebrates, that can cause significant morbidity and mortality. The common genus Myxidium infects the excretory system of turtles, yet knowledge of its pathogenicity in these hosts is limited. We offer new knowledge of morphological and ultrastructural aspects of host-parasite interactions in Myxidium infections from our recent diagnostic investigations on captive freshwater turtles listed in CITES (Appendix II). We investigated the cause of death of 2 adult Indo-Gangetic flap-shelled turtles Lissemys punctata andersonii from a zoo collection. After post-mortem examination, tissues were processed for histopathology, and special stains were used to demonstrate morphology of myxosporean spores. Additional kidney tissue, immersion-fixed in formalin, was processed for transmission electron microscopy. Both turtles were infected with a myxosporidian, Myxidium mackiei, in the kidney, which occluded 5 to 10% of the renal proximal convoluted tubules. The polysporic plasmodia contained pairs of developing and mature spores. Each mature, spindle-shaped spore had 2 asymmetric valves (1 overlapping, 1 overlapped), with 10 to 13 and 10 to 14 longitudinal ridges per valve, and 2 polar capsules each containing a polar filament with 4 to 5 turns. A pair of spores, each surrounded by a membrane-bound electron-lucent matrix, lay in an enclosing cell within the plasmodium. Regions of the parasite-host interface consisted of undulations of the parasite surface, with intense pinocytotic activity beneath, intermingled with the hosts' microvilli, and endocytotic channels at the apex of renal epithelial cells. The microvilli of the renal epithelial cells of infected tubules were frequently sheared or compressed, or occasionally missing; we did not detect other pathology induced by the parasite. Our report of M. mackiei in L. punctata is a new host record. Both individuals also had disseminated pale yellow nodules (bacterial granulomas) present in lung, heart, kidney, and skeletal muscle, and both were infected with coccidia (tentatively identified as Eimeria sp.) in multiple organs. The cause of death for one turtle was septicemia, but remained unknown for the other individual.

Animals↗
PubMed1999

DNA fingerprinting of Fusarium solani isolates related to a cutaneous infection in a sea turtle.

Random amplified polymorphic DNA (RAPD) fingerprinting was applied to Fusarium solani from a cutaneous hyalohyphomycosis in a loggerhead sea turtle. A total of seven F. solani isolates were examined, three from culture collections and four from the turtle infection (one from the turtle's lesions and three from the sand of the tank in which the turtle was kept). The banding patterns of the isolates from culture collections were markedly different from the patterns of the isolates from both the turtle and the sand. The RAPD banding patterns were the same with all the primers used, suggesting that this opportunistic infection may be related to the presence of F. solani in the tank. RAPD techniques can be particularly useful for large-scale epidemiological studies and for identifying sources of infection.

Animals↗
PubMed2000

[Identification of turtle shell, tortoise plastron and their counterfeit products].

OBJECTIVE: To identify the commercial Chinese medicines turtle shell and tortoise plastron. METHOD: Morphological identification and differential thermal analysis (DTA). RESULT: 2 kinds of counterfeit turtle shell and 3 kinds of counterfeit tortoise plastron were found, and their morphological and DTA identification features were proposed. CONCLUSION: Sea turtle shells presently on the market are sham commodities of turtle shell, which derive from Lissemys punctata and Pelochelys bibroni indigenous to south Asia, while plastrons of Ocadia sinensis, Chelonia mydas and Lepidochelys olivacea are counterfeit products of tortoise plastron. Turtle shells, tortoise plastrons and their counterfeit products may be exactly distinguished by morphological and DTA features.

Animals↗
PubMed2002

[Thermal tolerance, diel variation of body temperature, and thermal dependence of locomotor performance of hatchling soft-shelled turtles, Trionyx sinensis].

The thermal tolerance, body temperature, and influence of temperature on locomotor performance of hatchling soft-shelled turtles (Trionyx sinensis) were studied under dry and wet conditions, and the selected body temperature of hatchlings was 28.0 and 30.3 degrees C, respectively. Under wet condition, the critical thermal maximum and minimum averaged 40.9 and 7.8 degrees C, respectively. In the environments without thermal gradients, the diel variation of body temperature was highly consistent with the variation of both air and water temperatures, and the body temperature was more directly affected by water temperature than by air temperature, which implied that the physiological thermoregulation of hatchling T. sinensis was very weak. In the environments with thermal gradients, hatchling turtles could maintain relatively high and constant body temperatures, primarily through behavioral thermoregulation. The locomotor performance of hatchling turtles was highly dependent on their body temperature. Within a certain range, the locomotor performance increased with increasing body temperature. In our study, the optimal body temperature for locomotor performance was 31.5 degrees C, under which, the maximum continuous running distance, running distance per minute, and number of stops per minute averaged 1.87 m, 4.92 m.min-1, and 6.2 times.min-1, respectively. The correspondent values at 33.0 degrees C averaged 1.30 m, 4.28 m.min-1, and 7.7 times.min-1, respectively, which indicated that the locomotor performance of hatchling turtles was impaired at 33.0 degrees C. Therefore, extremely high body temperatures might have an adverse effect on locomotor performance of hatchling turtles.

Animals↗
PubMed2004

[Immunological up-regulation of cyclophosphamide-treated mice by turtle blood extract].

AIM: To explore the effect of turtle blood extract on murine immune system. METHODS: We compared the ratio of CD4(+) helper T cells and CD8(+) T cells, NK cell activity, lymphocyte proliferation stimulated by mitogen and capability of cytokine secretion of cyclosphophamide-treated mice with or without treatment of turtle blood extract. RESULTS: Turtle blood extract-treated mice displayed increased CD4(+) helper T cell population, stronger cytotoxicity of NK cells and enhanced of ConA-induced lymphocyte proliferation. In addition, the capacity of IFN-gamma secretion was dramatically up-regulated in turtle blood extract-treated mice group. CONCLUSION: Turtle blood extract can upregulate the immune function of cyclosphophamide-treated mouse.

Adjuvants, Immunologic↗
PubMed2004

Adrenocortical involvement during diverse stress in soft-shelled turtle Lissemys p. punctata Bonnoterre.

Adrenocortical responses to diverse stressful situations (dehydration, formaldehyde treatment and salt loading) were studied in the adult female soft-shelled turtle, Lissenmys p. punctata. Dehydration, formaldehyde treatment (formalin, 1%: 0.1 ml/100 g body weight daily) or salt loading (NaCl, 1%: 0.1 ml/100 g body weight daily) treatments consecutively for 7 days caused hypertrophy of the adrenocortical cells with their nuclear diameter increased, and depletions of adrenal cholesterol and ascorbic acid concentrations followed by decreased acid phosphatase and alkaline phosphatase activities in turtles. Corticosterone levels were elevated in both the adrenal gland and serum of turtles after dehydration and formalin stress, but the hormone level remained unaltered after salt loading in turtles. The results suggest active involvement of adrenal cortex in stress for homeostasis in Lissemys turtles.

Acid Phosphatase↗
PubMed2004

[Fundamental study on the cholesterol-lowering effect of whole turtle egg powder in SD rats].

OBJECTIVE: In order to study the cholesterol-lowering effects of whole turtle egg powder. METHODS: Fifty male SD rats were randomly divided into 5 groups according to body weight and serum cholesterol levels. They were fed one of five diets, a chow diet, a high fat supplemented diet (HF) and a HF diet supplemented with 0.75, 1.50 and or 3.00 g/kg BW whole turtle egg powder. After 24 weeks, collecting of the fecal and blood, serum total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) levels were determined by enzymic methods on an automatic analyzer. RESULTS: The serum TC levels were significantly decreased in both 1.50 g/kg BW group and 3.00 g/kg BW group compared with the HF rats (P < 0.05). Both 1.50 g/kg BW and 3.00 g/kg BW whole turtle egg powder increased fecal cholesterol, coprostanol and coprostanone excretion as well as total bile acids. CONCLUSION: The whole turtle egg powder lowered serum cholesterol by increasing the fecal steroids and turtle bile acids excretion.

Animals↗
PubMed2005

Sequence of a cDNA encoding turtle high mobility group 1 protein.

In order to understand sequence information about turtle HMG1 gene, a cDNA encoding HMG1 protein of the Chinese soft-shell turtle (Pelodiscus sinensis) was amplified by RT-PCR from kidney total RNA, and was cloned, sequenced and analyzed. The results revealed that the open reading frame (ORF) of turtle HMG1 cDNA is 606 bp long. The ORF codifies 202 amino acid residues, from which two DNA-binding domains and one polyacidic region are derived. The DNA-binding domains share higher amino acid identity with homologues sequences of chicken (96.5%) and mammalian (74%) than homologues sequence of rainbow trout (67%). The polyacidic region shows 84.6% amino acid homology with the equivalent region of chicken HMG1 cDNA. Turtle HMG1 protein contains 3 Cys residues located at completely conserved positions. Conservation in sequence and structure suggests that the functions of turtle HMG1 cDNA may be highly conserved during evolution. To our knowledge, this is the first report of HMG1 cDNA sequence in any reptilian.

Amino Acid Sequence↗
PubMed1992

A phylogenetic and biogeographic analysis of the genera of Spirorchinae (Digenea: Spirorchidae) parasitic in freshwater turtles.

Cladistic analysis of the freshwater genera of Spirorchinae (Schistosomatoidea: Spirorchidae sensu Yamaguti, 1971) plus Haematotrema Stunkard, 1923, and Aphanospirorchis Platt, 1990, was completed. The Spirorchinae were considered monophyletic based on synapomorphies of the esophagus. Three lineages, Spirhapalum (Europe/Asia), Plasmiorchis+Hemiorchis (India), and Spirorchis + Henotosoma + Haematotrema + Aphanospirorchis (North America), were identified. Nelsen consensus analysis was used as the basis for recognizing 3 valid monophyletic genera: Spirhapalum, Plasmiorchis, and Spirorchis. Hapalotrematinae sensu Smith, 1972 (e.g., Hapalorhynchus/Coeuritrema), is considered the most plesiomorphic group of spirorchids. Freshwater representatives of the hapalotrematines have been reported from 7 of 12 extant turtle families, including the relatively primitive Pelomedusidae (Pleurodira) and exhibit a worldwide distribution. It is hypothesized that this group arose in the early Triassic period, prior to the breakup of Pangea. Thus, it represents a primitive lineage that was present during the diversification of turtle lineages in the mid-Mesozoic era. Spirorchinae arose later (late Cretaceous period) as a Laurasian component parasitic in the more recent pond turtles (Emydidae + Bataguridae). Species of Spirhapalum retained a relatively plesiomorphic distribution, and they are found in emydids (Europe) and batagurids (Asia). Species of Spirorchis arose and diversified with North America emydids following the separation of North America and Europe in the late Cretaceous or early Tertiary periods. Species of Plasmiorchis are hypothesized to be derived from Asian ancestors that accompanied the colonization of India by Asian batagurids during the early Tertiary period. The presence of Spirorchis species in snapping turtles (Chelydridae/North America) and of Plasmiorchis species in Indian soft-shelled turtle (Trionychidae) are considered independent colonization events.

Animals↗
PubMed1988

Ganglion cells in the turtle retina contain the neuropeptide LANT-6.

This study investigated the presence of the neurotensin-related hexapeptide, LANT-6, in retinal ganglion cells and their central projections in the turtle Pseudemys scripta elegans. Immunocytochemical techniques demonstrated that many of the cells in the ganglion cell layer of the turtle retina could be labeled with an antiserum specific for LANT-6. Radioimmunoassay and chromatographic analysis confirmed the presence of LANT-6-related peptides in retina, as well as brain. Several molecular forms of LANT-6 were observed, some larger than LANT-6. Characterization of the cells labeled in the ganglion cell layer in terms of their cell body size and their dendritic arborization patterns revealed that at least 6 specific LANT-6-positive cell types were present in the ganglion cell layer. Morphologically, the LANT-6-positive cells strongly resembled turtle ganglion cells, as previously described. In addition, two other lines of evidence supported this interpretation. First, double-label studies were performed in which retinal ganglion cells projecting to the tectum were retrogradely labeled by HRP injected into the tectum (using a cobalt chloride color-modified DAB reaction product) and immunocytochemically labeled with DAB using the antiserum against LANT-6. These double-label studies revealed that many of the LANT-6-positive cells in the ganglion cell layer in the portion of the retina labeled retrogradely by the HRP injection did project to the tectum. Within the retrogradely labeled portion of the retina, LANT-6-positive cells that were not labeled retrogradely, as well as neurons labeled retrogradely that did not contain LANT-6 were also observed. Second, the central projections of LANT-6-positive cells of the ganglion cell layer were examined by studying the effects of monocular enucleation on the distribution of LANT-6-positive fibers in the central projection targets of the turtle retina. Two to 8 weeks after enucleation, a substantial reduction in LANT-6-positive fibers was observed in all retinal target areas contralateral to the enucleated eye. Radioimmunoassay and chromatographic studies confirmed the presence of LANT-6-related peptides in the turtle brain and corroborated the reduction of LANT-6 observed in the contralateral tectum following monocular enucleation. Previous studies have demonstrated that LANT-6-related material is present in cells of the ganglion cell layer in a variety of vertebrates. The present results indicate that LANT-6 is in ganglion cells and that it may play a role in neurotransmission between retinal ganglion cells and their central target areas.

Animals↗
PubMed1978

Activation of latent Salmonella and Arizona organisms by dehydration of red-eared turtles, Pseudemys scripta-elegans.

Salmonella and Arizona organisms could not be isolated from water samples, feces, and tissues of turtles prior to the experiment. After stressing, Salmonella organisms were isolated from tissues of 7 of 27 stressed turtles and from only 1 of 12 unstressed turtles. Arizona organisms were isolated from 9 of 36 stressed turtles whereas results for all 12 unstressed turtles were negative.

Animals↗
PubMed1983

Transplantation of turtle embryonic thymus into quail embryo: colonization by quail cells.

Turtle (Emys orbicularis L.) embryo thymuses grafted in the somatopleure or onto the quail embryo chorioallantoic membrane developed in these heterotopic sites for 2-12 days. When the thymus was removed from embryos at early stages such that no thymocytes were yet present during normal development, epithelial cells with mitoses were observed in the explants but no turtle thymocytes developed whatever the duration of explantation. An extrinsic origin of lymphoid precursor cells can explain such results. Quail lymphoid-like cells distinguishable from turtle cells by their nuclear structure began entering the explants 5 days after grafting. Their number increased progressively until the 12th day, when all the grafts were retrieved. When an already lymphoid thymus was removed from embryos at later stages, turtle thymocytes remained fairly abundant in the explants until 5 days. Beyond this period, they gradually disappeared. After 11-12 days, none were left and only epithelial tissue from the turtle was present, showing excellent development. Quail lymphoid-like cells entered this more mature thymus following the same time course as they did in the early rudiment. Thus we observed no difference between attraction of quail lymphoid cells by the precolonization thymic epithelium or by the lymphoid thymus.

Animals↗
PubMed1994

New host and geographic records for coccidia (Apicomplexa: Eimeriidae) from North American turtles.

Two-hundred-fifty-three turtles, representing 26 species within 5 families (Chelydridae, Emydidae, Kinosternidae, Testudinidae, Trionychidae) were examined for coccidia. Of these, 127 (50%) were found to harbor 1 or more of 28 species of eimerians, or isosporan, or both. One-hundred-thirteen (89%) of the infected turtles were aquatic species, whereas only 14 (11%) of the infected turtles were terrestrial species. Two-fold more aquatic turtles were infected with coccidia (113 of 200, 57%) compared to only 26% (14 of 53) of the terrestrial species. This report documents 14 new host and 8 new geographic records for eimerians from turtles in Arkansas and Texas.

Animals↗
PubMed1994

[Morphometric variation and ecologic characteristics of the habitat of the Kinosternon scorpioides turtle in Costa Rica (Chelonia,Kinosternidae)].

Kinosternon scorpioides shows sexual dimorphism in Costa Rica. Males are bigger than females since in the length of the shell ranges between 15.0-17.5 cm (average: 16.10 cm) and in these ones between 12.4-15.9 cm (average: 13.8 cm). According to the Life Zone System of Holdridge, K. scorpioides is in two geographic regions with different characteristics, one situated in the tropical dry forest zone and the other in tropical very rain forest. Morphometric variation is evident since females, more rounded, are in the first life zone, and males, more elongated, in the second zone. Shape and size of the shell of the turtles is a fit adaptation in their habitats because the average height of the shell of the turtles in tropical very rain forest is smaller than the average height in the tropical dry forest. This means that turtles of tropical very rain forest are more smoothed and more hydrodynamics than the others, which might to be advantageous for the swim very quickly and to hide out in the numerous tunnels or caves on the banks of the streams when they are attacked by jaguars or other predators. This life zone has several perennial streams without rocks, while on tropical dry forest zone, small seasonal lakes and marshes prevail during all year with abundant aquatic vegetation which obstructs the free displacement of the turtles. Likewise, the tropical very rain forest zone has 80% of turtles with physical damages produced by jaguars, while in tropical dry forest none of them shows this type of damages.

Animals↗
PubMed1998

Embryonic temperature influences juvenile temperature choice and growth rate in snapping turtles Chelydra serpentina.

Snapping turtles (Chelydra serpentina) demonstrate temperature-dependent sex determination (TSD): intermediate egg incubation temperatures (23-27 degrees C) produce males, while extreme temperatures produce females. Snapping turtles are also sexually dimorphic: adult males are typically larger than females. Previous researchers hypothesized that male-producing egg temperatures enhanced the growth rate of juvenile turtles, resulting in the adult dimorphism and potentially providing an adaptive benefit for TSD. In reptiles, the choice of ambient temperature can also influence growth. I measured the effect of egg incubation temperature on juvenile growth rate and water temperature choice of C. serpentina. Eggs were incubated in the laboratory at 21.5, 24.5, 27.5 or 30.5 degrees C to produce both sexes, all males, both sexes or all females, respectively. Egg temperature was linearly and negatively correlated with growth rate of both male and female juveniles. Thus, growth was enhanced, but not maximized, by male-producing egg temperatures. Egg temperature was also negatively correlated with juvenile temperature choice such that, on average, turtles from 21.5 degrees C eggs selected 28 degrees C water, while turtles from 30.5 degrees C eggs chose 24.5 degrees C water. Additionally, these temperature choices were highly repeatable, even following a 6 month hibernation period at 7 degrees C. Thus, while male egg temperatures do not directly maximize growth, multiple effects of embryonic temperature may combine to create long-lasting differences in the behavioral physiology of male and female C. serpentina. Such differences could be important to the ecology and evolution of TSD.

Animals↗
PubMed2004

Pulmonary hyalohyphomycosis caused by Fusarium spp in a Kemp's ridley sea turtle (Lepidochelys kempi): an immunohistochemical study.

AIM: To describe the microscopic and immunohistochemical findings in a case of pulmonary hyalohyphomycosis in a Kemp's ridley sea turtle (Lepidochelys kempi). METHODS: Samples of lung, liver and kidney from a stranded, dead Kemp's ridley sea turtle were routinely processed for histopathological studies. Two monoclonal antibodies that reacted specifically with antigens of Aspergillus spp and the Mucorales (Zygomycetes) group, and a panel of polyclonal antibodies raised against Aspergillus fumigatus, Candida albicans, Geotrichum candidum, Fusarium solani, and Scedosporium apiospermum were used for immunohistochemical or immunofluorescence staining. RESULTS: Histologically, a severe multifocal granulomatous pneumonia associated with fungal infection was diagnosed. All hyphae were identified as Fusarium spp because a strong and uniform reactivity was obtained only with a heterologously-absorbed polyclonal antibody raised against somatic antigens of Fusarium solani. CONCLUSIONS: Fusarium spp should be included in the differential diagnosis of mycotic pneumonia in Kemp's ridley sea turtles. CLINICAL RELEVANCE: This is the first report of a pulmonary mycotic infection in a sea turtle diagnosed using immunohistochemistry. Wildlife rehabilitators and pathologists should be aware of the availability of immunohistochemical techniques for identifying fungi in sea turtles.

Journal Article↗
PubMed1996

Orientation and open-sea navigation in sea turtles

Loggerhead sea turtle hatchlings (Caretta caretta L.) emerge from underground nests, scramble to the sea and begin a transoceanic migration by swimming away from their natal beach and into the open ocean. Evidence suggests that hatchlings sequentially use three different sets of cues to maintain orientation during their initial migration offshore. While on the beach, hatchlings find the ocean by crawling towards the lower, brighter seaward horizon and away from the dark, elevated silhouettes of vegetation and dunes. Upon entering the ocean, turtles initially orient seawards by swimming into waves, which can be detected as orbital movements from under water. Laboratory experiments have demonstrated that turtles can transfer a course initiated on the basis of waves or visual cues to a course mediated by a magnetic compass. Thus, by setting a magnetic course on the basis of nearshore cues that indicate the seaward direction, hatchlings may continue on offshore headings after entering deep water beyond sight of land. Sea turtles may use the earth's magnetic field not only as a cue for compass orientation but also as a source of world-wide positional information. Recent experiments have demonstrated that loggerheads can detect subtle differences in magnetic field inclination and intensity, two geomagnetic features that vary across the surface of the earth. Because most nesting beaches and oceanic regions are marked by a unique combination of these features, these findings raise the possibility that adult sea turtles navigate using a bicoordinate magnetic map.

Journal Article↗