| a novel host-adapted strain of salmonella typhimurium causes renal disease in olive ridley turtles (lepidochelys olivacea) in the pacific. | salmonella spp. are frequently shed by wildlife including turtles, but s. enterica subsp. enterica serovar typhimurium or lesions associated with salmonella are rare in turtles. between 1996 and 2016, we necropsied 127 apparently healthy pelagic olive ridley turtles (lepidochelys olivacea) that died from drowning bycatch in fisheries and 44 live or freshly dead stranded turtles from the west coast of north and central america and hawaii. seven percent (9/127) of pelagic and 47% (21/44) of strand ... | 2019 | 31249336 |
| first report of fibropapillomatosis in an olive ridley turtle lepidochelys olivacea from the southeastern pacific. | an adult olive ridley turtle lepidochelys olivacea with lesions suggestive of fibropapillomatosis was rescued on the coast of san antonio, central chile. histopathologic analysis showed an exophytic and pedunculated mass formed by epidermal papillary projections supported by fibrovascular cores, epidermal hyperplasia and marked orthokeratotic hyperkeratosis. chhv5 unique long genes ul27, ul28 and ul30 were amplified from tumor lesions and sequenced for phylogeny. phylogenetic reconstruction show ... | 2019 | 31244483 |
| supernumerary scutes verify a segment-dependent model of the horny shell development in turtles. | turtle horny shell has a scute pattern, which is conservative through evolution and across species. the discovery of epidermal placodes as the scute primordia and their strict topographical association to the somites of the turtle embryo suggested a new interpretation of the developmental mechanism of the scute pattern. here, we tested the hypothesis that horny scutes develop from a mosaic of placodes corresponding exactly to the paths of myoseptae, with vertebral and pleural scutes developing s ... | 2019 | 31198986 |
| methylation status of the putative pax6 promoter in olive ridley sea turtle embryos with eye defects: an initial approach. | normal development involves the interplay of genetic and epigenetic regulatory mechanisms. pax6 is an eye-selector factor responsible for initiating the regulatory cascade for the development of the eyes. for the olive ridley sea turtle (lepidochelys olivacea), a threatened species, eye malformations have been reported. in order to study the dna methylation status of the putative promoter of the pax6 gene in embryos with ocular malformations, an exploratory study was carried out in which dna was ... | 2018 | 30110613 |
| mercury concentration, dna methylation, and mitochondrial dna damage in olive ridley sea turtle embryos with schistosomus reflexus syndrome. | schistosomus reflexus syndrome (sr) is a rare and lethal congenital malformation that has been reported in the olive ridley sea turtle (lepidochelys olivacea) in mexico. although the etiology remains unclear, it is presumed to be genetic. since embryonic development in sea turtles largely depends on environmental conditions, we investigated whether sea turtle total mercury content participates in the etiology of sr. given that several toxins are known to affect both dna methylation and/or mitoch ... | 2019 | 31434549 |
| relationship between plasma biochemistry values and metal concentrations in nesting olive ridley sea turtles. | a hundred nesting olive ridley turtles were sampled to determine biochemical parameters (alp, ast, alt, creatinine, albumin, cholesterol, glucose, proteins, triglycerides, urea, and p-nitrophenyl acetate esterase activity). esterase activity (ea) is a new biomarker very sensitive to metals. most of the samples showed detectable levels. we also analyzed the concentration of 11 inorganic elements (as, cd, cr, cu, mn, ni, pb, sr, ti, se, and zn), some of them previously reported with very high conc ... | 2018 | 30377965 |
| synchronised nesting aggregations are associated with enhanced capacity for extended embryonic arrest in olive ridley sea turtles. | sea turtle species in the genus lepidochelys exhibit an unusual behavioural polymorphism, nesting in both aggregations and solitarily. aggregated nesting events, termed 'arribadas', involve hundreds of thousands of females congregating at a single nesting beach over a few days to oviposit their eggs. aggregate and solitary nesting behaviours are associated with distinct inter-nesting intervals, three and four weeks for non-arribada and arribada nesters respectively. consequently, embryos are mai ... | 2019 | 31278292 |
| isolation by environment in the highly mobile olive ridley turtle (lepidochelys olivacea) in the eastern pacific. | spatial and temporal scales at which processes modulate genetic diversity over the landscape are usually overlooked, impacting the design of conservation management practices for widely distributed species. we examine processes shaping population divergence in highly mobile species by re-assessing the case of panmixia in the iconic olive ridley turtle from the eastern pacific. we implemented a biophysical model of connectivity and a seascape genetic analysis based on nuclear dna variation of 634 ... | 2018 | 29720414 |
| carapace asymmetry: a possible biomarker for metal accumulation in adult olive ridleys marine turtles? | the olive ridley marine turtle (lepidochelys olivacea) is characterized by individual morphological variability in the number and shape of scutes. the influence of pollutants on developmental instability and one of its consequences, the asymmetry of individuals, has been demonstrated in several species, especially invertebrates and some birds. however, the use of this asymmetry as a biomarker of contamination in adult individuals has never been explored. we developed an index to quantify develop ... | 2018 | 29680573 |
| blood biochemistry of olive ridley (lepidochelys olivacea) sea turtles foraging in northern sinaloa, mexico. | blood parameters provide an excellent tool to evaluate the health status of wildlife. however, there are few studies about health parameters of sea turtles in mexico. for olive ridley turtles (lepidochelys olivacea), no information was available to establish the health baseline for the species. the objective of this study was to establish reference blood biochemistry values for olive ridley turtles in the northern sinaloa foraging area. between 2013 and 2015, 82 olive ridley turtles were capture ... | 2018 | 30044783 |
| presence of chelonid herpesvirus 5 (chhv5) in sea turtles in northern sinaloa, mexico. | the presence of fibropapilloma and its associated chelonid herpesvirus 5 (chhv5) was assessed in 82 wild sea turtles. olive ridley turtles lepidochelys olivacea (n = 58) were caught in the pelagic area of marine influence (ami) (off the coast of guasave, sinaloa), and black turtles chelonia mydas agassizii (n = 24) were captured in the navachiste lagoon system. the apparent physical condition was evaluated as 'good' or 'poor' by physical examination. the population structure and general health s ... | 2019 | 30628576 |
| large-scale connectivity, cryptic population structure, and relatedness in eastern pacific olive ridley sea turtles (lepidochelys olivacea). | endangered species are grouped into genetically discrete populations to direct conservation efforts. mitochondrial control region (mtcr) haplotypes are used to elucidate deep divergences between populations, as compared to nuclear microsatellites that can detect recent structuring. when prior populations are unknown, it is useful to subject microsatellite data to clustering and/or ordination population inference. olive ridley sea turtles (lepidochelys olivacea) are the most abundant sea turtle, ... | 2020 | 32884651 |
| optimized technique to extract and fix olive ridley turtle hatchling retina for histological study. | the efficient extraction and fixation of a tissue allows in preserving the cytoarchitecture, chemical composition and tissue organization, which is key in physiological and histopathological studies. the main goal of this study was to establish a microsurgery technique to obtain ocular tissue and provide an optimized immersion fixation protocol based on the 10 % formalin-intraocular injection on olive ridley sea turtle hatchlings (lepidochelys olivacea). to evaluate this optimized technique, a h ... | 2020 | 32778246 |
| introduction of developmental biology at utkal university, (odisha, india). | the paper deals with the background and the establishment of a developmental biology laboratory in utkal university in odisha state. it describes the process from a humble beginning with limited facilities into a leading research centre, initially for amphibians and later for the endangered olive ridley (lepidochelys olivacea) turtle. starting from the biology, reproduction and development in many anurans, the laboratory took up research on regeneration, especially on super-regeneration in tadpo ... | 2020 | 32659019 |
| spatiotemporal expression of foxl2 and dmrt1 before, during, and after sex determination in the sea turtle lepidochelys olivacea. | the sex of sea turtles is determined by temperature during egg incubation. thus, climate change affects the sex ratio, exacerbating their vulnerability to extinction. understanding spatiotemporal effects of temperature on sex determination at the gonadal level may facilitate the design of strategies to mitigate the effects of global warming. here, we used qrt-pcr and immunofluorescence to analyze the spatiotemporal expression of dmrt1 and foxl2 in developing gonads of lepidochelys olivacea incub ... | 2019 | 32396908 |
| recent advances on the estimation of the thermal reaction norm for sex ratios. | temperature-dependent sex determination, or tsd, is a widespread phenomenon in reptiles. the shape of the relationship between constant incubation temperature and sex ratio defines the tsd pattern. the tsd pattern is considered a life-history parameter important for conservation because the wider the range of temperatures producing both sexes, the more resilient the species is to climate change impacts. we review the different published equations and methodologies that have been used to model ts ... | 2020 | 32181050 |
| spatial distribution of epibionts on olive ridley sea turtles at playa ostional, costa rica. | there is a wealth of published information on the epibiont communities of sea turtles, yet many of these studies have exclusively sampled epibionts found only on the carapace. considering that epibionts may be found on almost all body-surfaces and that it is highly plausible to expect different regions of the body to host distinct epibiont taxa, there is a need for quantitative information on the spatial variation of epibiont communities on turtles. to achieve this, we measured how total epibion ... | 2019 | 31490927 |
| monitoring data of marine turtles on the togolese coast during 2012-2013. | this dataset contains information on the presence and distribution of sea turtles in togo. observations were carried out through a network of ten ecoguards (local guides), facilitated by five fishermen, and coordinated by a field technician, all under the supervision of a scientific coordinator. data on the occurrence or direct observation of sea turtles on the togolese coast from september 2012 to august 2013 is presented based on 740 occurrences. | 2018 | 30123024 |
| blood oxygen stores of olive ridley sea turtles, lepidochelys olivacea are highly variable among individuals during arribada nesting. | sea turtles dive with a full lung of air and these o2 stores are supplemented by o2 stored in blood and muscle. olive ridley sea turtles exhibit polymorphic nesting behavior, mass nesting behavior called arribada, where thousands of turtles will nest at once, and solitary nesting behavior. the potential physiological differences between the individuals using these strategies are not well understood. we measured blood volume and associated variables, including blood hemoglobin content and hematoc ... | 2020 | 33064209 |
| spatiotemporal variation in lepidochelys olivacea sea turtle nests and their influence on the abundance and reproductive phenology of the sapro-necrophagous beetle omorgus suberosus. | the olive ridley sea turtle, lepidochelys olivacea (eschscholtz, 1829), nests en masse in the protected natural area of la escobilla, mexico. on this beach, omorgus suberosus (fabricius, 1775), a sapro-necrophagous beetle, feeds on the sea turtles' decomposing and live eggs and is considered to be a threat for the conservation of l. olivacea. however, the abundance and reproductive phenology of o. suberosus in relation to the spatial and temporal availability of this food resource are unknown. w ... | 2020 | 33017032 |