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1.
An Acad Bras Cienc ; 96(suppl 1): e20240484, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39319838

RESUMO

Ranacephala hogei is a South American freshwater turtle considered one of the 25 most endangered chelonian species in the world. Endemic to the Atlantic Forest hotspot of southeastern Brazil, the conservation status of R. hogei is subject to continuous assessment at various levels. However, the scarcity of data regarding this species, particularly its geographic range, challenges these evaluations. In an effort to address these gaps, we conducted a comprehensive long-term inventory using different methods to study this species. Our efforts resulted in a 144% increase in documented occurrence points, including a new hydrographic basin and protected areas. By combining historical and current records, we have observed the persistence of R. hogei in rural areas, even in locations where its extinction was previously predicted. Consequently, our data significantly contribute to supporting future conservation assessments.


Assuntos
Ciência do Cidadão , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Tartarugas , Animais , Tartarugas/classificação , Brasil , Distribuição Animal , Densidade Demográfica , Água Doce
2.
Open Vet J ; 14(8): 1789-1793, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39308705

RESUMO

Background: The popularity of tortoises kept in captivity is increasing and has caused concern regarding the necessity to establish safe and straightforward anaesthesia for those reptiles. Aim: This study aimed to compare four protocols using levobupivacaine in spinal anaesthesia for the blockade of the caudal neuraxis of red-footed tortoises (Chelonoidis carbonarius). Methods: Twenty-four tortoises were randomly assigned into four groups: G1, levobupivacaine 0.75% (1.15 mg kg-1); G2, levobupivacaine 0.37% (1.15 mg kg-1); G3, levobupivacaine 0.75% (2.3 mg kg-1); and G4, levobupivacaine 0.75% (0.1 ml 5 cm-1 of straight carapace length). Tortoises were evaluated for respiratory rate, muscle relaxation, response to hindlimb or tail pinch, and cloacal reflex. Results: A 1.15 mg kg-1 dose of levobupivacaine 0.37% appears adequate for shorter procedures, whereas a 1.15 mg kg-1 dose of levobupivacaine 0.75% should be appropriate for longer procedures in red-footed tortoises. Conclusion: Our results are the first to show the effects of levobupivacaine on spinal anaesthesia in reptiles. Weight-based doses presented more intense and more homogeneous effects than carapace length-based doses in red-footed tortoises. Spinal anaesthesia of red-footed tortoises was safe and effective with any of the weight-based protocols.


Assuntos
Raquianestesia , Anestésicos Locais , Levobupivacaína , Tartarugas , Animais , Levobupivacaína/administração & dosagem , Levobupivacaína/farmacologia , Raquianestesia/veterinária , Raquianestesia/métodos , Anestésicos Locais/farmacologia , Anestésicos Locais/administração & dosagem , Masculino , Feminino
3.
J Exp Biol ; 227(19)2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39264243

RESUMO

Testudines possess a rigid shell that influences the mechanics of the respiratory system. We studied respiratory mechanics in the terrestrial red-footed tortoise Chelonoidis carbonarius (Cryptodira), comparing juvenile individuals with a less ossified and more flexible carapace with adults with a well-ossified rigid shell. Combined with these ontogenetic differences, we analyzed respiratory system mechanics with animals in a supine and a prone position, as well as in the isolated lungs, to evaluate the impact of the viscera on breathing mechanics. To do so, we used established protocols to measure pulmonary volume (i.e. resting, VLr; and maximum, VLm), static (Cstat) and dynamic (Cdyn) compliance, and the work of breathing (W). We observed that isolated lungs displayed increased VLr, VLm, Cstat and Cdyn and decreased W. Additionally, pulmonary volume, compliance and W were affected by evaluated position, such as a smaller VLr in a supine position. Cdyn and W showed a volume dependency while frequency had less influence on these variables. At similar levels of ventilation, juveniles showed a lower W than adults when standardized by body mass, but similar W when standardized by VLr. Clear ontogenetic changes could be observed in breathing mechanics between juvenile and adult C. carbonarius. While these differences might largely be explained by variation in shell ossification, other explanations such as differences in visceral proportions or developmental degree of the post-pulmonary septum should also be taken into account.


Assuntos
Pulmão , Mecânica Respiratória , Tartarugas , Animais , Pulmão/fisiologia , Pulmão/crescimento & desenvolvimento , Tartarugas/fisiologia , Tartarugas/crescimento & desenvolvimento , Mecânica Respiratória/fisiologia , Masculino
4.
Environ Monit Assess ; 196(9): 862, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212756

RESUMO

Turtle species in the Family Podocnemididae, including the Colombian endemic and critically endangered Magdalena River Turtle Podocnemis lewyana, characteristically present low recapture rates that preclude estimation of population parameters using maximum likelihood modeling. In our 12-year monitoring project with this species, we evaluated changes in relative abundances, proportions of sex/size classes, and individual body sizes and body conditions in a population in four channels in the middle Magdalena River drainage. We also inspected for associations between trends in changes in these variables and differences in hunting pressure and habitat degradation. To inspect for temporal and spatial demographic dynamics, we estimated variation in relative abundances using the Catch Per Unit Effort index, the total number of turtles captured over an entire 5-day sampling period using ten baited funnel traps. Relative abundances and the proportions of sex/size classes were different between sites and years. We found a significant decline in the proportion of females and juveniles over time, along with evidence that the females still present were smaller in body size. Our results support the hypothesis that hunting eliminates adult females from these sites, perhaps also translating into a reduction in recruitment. The lack of evidence of generalized declines in body condition of all size classes suggests that habitat degradation might contribute less to the population declines in this region. Our results also illustrate that even when recapture rates are low, monitoring turtles via standardized trapping may yield insights into the population's conservation status that other relative abundance indices cannot.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Rios , Tartarugas , Animais , Caça , Feminino , Masculino , Monitoramento Ambiental/métodos , Dinâmica Populacional , Colômbia
5.
J Appl Microbiol ; 135(8)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39108090

RESUMO

AIMS: This study aimed to describe the bacterial microbiome associated with the carapace of three species of Galapagos giant tortoises (Chelonoidis porteri, Chelonoidis donfaustoi, and Chelonoidis vandenburghi) and determine the potential effect of the whitish lesions caused by the fungus Aphanoascella galapagosensis. METHODS AND RESULTS: We used Oxford Nanopore's MinION to evaluate the external bacterial microbiome associated with the carapaces from the aforementioned species. Taxonomic assignment was carried out by Bugseq and the bacterial communities were compared between carapaces with and without lesions using a NMDS with Bray-Curtis as the dissimilarity index. We found four genera of bacteria that were ubiquitous throughout all individuals, suggesting the presence of shared taxa. The results also displayed a significant difference in the microbiome between carapaces with and without lesions, and for species-carapace interaction, but not among species. CONCLUSIONS: This study establishes a baseline of the bacterial diversity of the carapace within three Galapagos giant tortoise species, showcasing the presence of a distinctive microbial community. Furthermore, our findings suggest a significant influence of the fungus Aphanoascella galapagosensis on the bacterial populations inhabiting the carapace of these reptiles.


Assuntos
Bactérias , Microbiota , Tartarugas , Animais , Tartarugas/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Exoesqueleto/microbiologia , Biodiversidade
6.
An Acad Bras Cienc ; 96(suppl 1): e20231185, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109698

RESUMO

To address urban turtle sampling challenges, we presented Hookless fishing with clip, a cost-effective method for sampling this important group. Effectiveness, biases and potential advantages were analysed in comparison to two commonly used methods (funnel trap and hand capture). Fieldwork was conducted between August and November/2021 in four areas in Brazil, using the three methods simultaneously. A total of 195 turtles from four species (Phrynops geoffroanus, Hydromedusa tectifera, Trachemys dorbigni and T. scripta elegans) were captured. Funnel trap demonstrate a significantly higher capture than hand capture, while Hookless fishing showed no significant difference in captures compared to funnel trap. The highest catch per unit effort values were observed for the new method (0.37) and the funnel trap (0.34). Despite being widely used, funnel traps were the only method to exhibit male bias. Our findings revealed that Hookless fishing with clip exhibited remarkable capture efficiency, cost-effectiveness, and ease of transport and utilization; however, it requires operator presence. Nevertheless, the proposed method, both as the primary or auxiliary approach, appears efficient in enhancing captures and reducing costs and risks. This innovative method has the potential to assist researchers studying omnivorous and carnivores freshwater turtles in environments worldwide, especially in human settlements.


Assuntos
Tartarugas , Animais , Tartarugas/classificação , Brasil , Masculino , Feminino , Caça , Análise Custo-Benefício
7.
An Acad Bras Cienc ; 96(3): e20230753, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985031

RESUMO

The larynx is in the lower respiratory tract and has the function of protecting the airways, controlling, and modulating breathing, assisting the circulatory system, and vocalizing. This study aims to describe the anatomy and histology of the skeleton of the larynx and trachea of the species Chelonia mydas, Caiman yacare and Caiman latirostris. The study was conducted at the Federal University of Espírito Santo (UFES), using nine specimens of Ch. mydas, 20 of Ca. yacare and four of Ca. latirostris. Samples of the larynx and trachea were collected, fixed, and sent for dissection of the structures and subsequent macroscopic analysis. For histology, samples were processed by the routine paraffin embedding method and stained with hematoxylin-eosin and Verhoeff. For the three species, two arytenoid cartilages, a cricoid cartilage, a hyoid apparatus composed of a base and two horns were found. In Ch. mydas, two structures called thyroid wings were observed, not found in crocodilians. The trachea of crocodilians presented incomplete tracheal rings and musculature, while the trachea of Ch. mydas presented complete tracheal rings. Histologically, the entire cartilaginous skeleton of the larynx of the three species, as well as the tracheal rings, are constituted by hyaline cartilage.


Assuntos
Jacarés e Crocodilos , Laringe , Traqueia , Tartarugas , Animais , Traqueia/anatomia & histologia , Jacarés e Crocodilos/anatomia & histologia , Laringe/anatomia & histologia , Tartarugas/anatomia & histologia
8.
Sci Total Environ ; 946: 174151, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38909804

RESUMO

Important foraging and nesting habitats for Caribbean green sea turtles (Chelonia mydas) exist within the Mesoamerican Reef System in the Mexican Caribbean. During the last 25 years, urban development and touristic activities have drastically increased in Quintana Roo, Mexico. Moreover, in the last decade, massive pelagic sargasso blooms have also afflicted this region; however, information about the biochemical responses of Caribbean green turtles to these inputs is absent. This study aimed to assess if the oxidative stress indicators in the red blood cells of green turtles are valuable biomarkers of the extent of the anthropic impact in this region. Persistent organic pollutants (POPs) were also measured in the plasma of free-living green turtles during 2015-2018 to characterize these habitats further. As biochemical biomarkers, the production rate of superoxide radical (O2•-), carbonylated protein content, and lipid peroxidation (TBARS) levels, and the activities of superoxide dismutase, glutathione S-transferase (GST), catalase, glutathione peroxidase were measured in erythrocytes. A 15 % occurrence of fibropapillomatosis (FP) was revealed, with tumor size being positively correlated with CAT activity in the affected individuals. A multivariate analysis embracing all oxidative stress markers discriminated green turtles between years of capture (p < 0.001), with those sampled during 2015 presenting the highest production of O2•- (p = 0.001), activities of GST (p < 0.001), levels of TBARS (p < 0.001) and carbonylated proteins (p = 0.02). These local and temporal biochemical responses coincided with the first massive Sargassum spp. bloom reported in the region. The results of this study corroborate the utility of the oxidative stress indicators as biomarkers of environmental conditions (sargasso blooms and POPs) in the green turtle as sentinel species.


Assuntos
Ecossistema , Monitoramento Ambiental , Estresse Oxidativo , Tartarugas , Animais , Tartarugas/fisiologia , México , Poluentes Químicos da Água/análise , Biomarcadores , Catalase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Sargassum/fisiologia , Superóxido Dismutase/metabolismo
9.
Vet Res Commun ; 48(5): 2943-2961, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38922387

RESUMO

Fibropapillomatosis (FP) - tumour-associated chelonid alphaherpesvirus 5 (ChHV5; Scutavirus chelonidalpha5) - is a disease that affect marine turtles around the world, and characterized by the formation of cutaneous tumours that can appear anywhere on the body. We carried out a thorough literature search (from 1990 to 2024) in the feeding sites of North-western Mexico, a region that hosts important habitats for feeding, development, and reproduction for five of the seven existing sea turtle species. We found 18 reports recording a total of 32 cases of FP and/or ChHV5/Scutavirus chelonidalpha5 in coastal and insular areas of North-western Mexico. Baja California Sur resulted with the highest number of cases (75%). While the first case of ChHV5/Scutavirus chelonidalpha5 infection was reported in 2004, the presence of FP tumours was reported in 2014 and became more frequent between 2019 and 2024. The affected species were black, Chelonia mydas (50%), olive ridley, Lepidochelys olivacea (46.8%) and loggerhead turtles, Caretta caretta (3.2%). Tumours occurred mainly in anterior flippers (46.1%) and neck (22.5%), and most had a nodular and verrucous appearance with a rough surface. In the study region, there is a potential sign of the emergence of the ChHV5/Scutavirus chelonidalpha5 infections and FP disease during the last 20 years, with a rapid increase during the last 10 years. As long as infections by ChHV5/Scutavirus chelonidalpha5 and the prevalence of the FP disease may be potentially influenced by anthropogenic activities, a One Health approach is needed to understand and improve sea turtles' health.


Assuntos
Alphaherpesvirinae , Infecções por Herpesviridae , Tartarugas , Tartarugas/virologia , Animais , México/epidemiologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/virologia , Alphaherpesvirinae/isolamento & purificação , Neoplasias Cutâneas/veterinária , Neoplasias Cutâneas/virologia , Neoplasias Cutâneas/epidemiologia , Papiloma/veterinária , Papiloma/virologia , Papiloma/epidemiologia , Papiloma/patologia
10.
Sci Rep ; 14(1): 14102, 2024 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-38890338

RESUMO

Large predators have disproportionate effects on their underlying food webs. Thus, appropriately assigning trophic positions has important conservation implications both for the predators themselves and for their prey. Large-bodied predators are often referred to as apex predators, implying that they are many trophic levels above primary producers. However, theoretical considerations predict both higher and lower trophic position with increasing body size. Nitrogen stable isotope values (δ15N) are increasingly replacing stomach contents or behavioral observations to assess trophic position and it is often assumed that ontogenetic dietary shifts result in higher trophic positions. Intraspecific studies based on δ15N values found a positive relationship between size and inferred trophic position. Here, we use datasets of predatory vertebrate ectotherms (crocodilians, turtles, lizards and fishes) to show that, although there are positive intraspecific relationships between size and δ15N values, relationships between stomach-content-based trophic level (TPdiet) and size are undetectable or negative. As there is usually no single value for 15N trophic discrimination factor (TDF) applicable to a predator species or its prey, estimates of trophic position based on δ15N in ectotherm vertebrates with large size ranges, may be inaccurate and biased. We urge a reconsideration of the sole use of δ15N values to assess trophic position and encourage the combined use of isotopes and stomach contents to assess diet and trophic level.


Assuntos
Tamanho Corporal , Cadeia Alimentar , Isótopos de Nitrogênio , Comportamento Predatório , Vertebrados , Animais , Isótopos de Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Comportamento Predatório/fisiologia , Lagartos/fisiologia , Lagartos/metabolismo , Peixes/fisiologia , Conteúdo Gastrointestinal/química , Tartarugas/fisiologia , Tartarugas/metabolismo
11.
Parasitol Res ; 123(6): 249, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907803

RESUMO

Species of Haemogregarina are blood parasites known to parasitise vertebrate hosts, including fishes (Haemogregarina sensu lato) and freshwater turtles (Haemogregarina sensu stricto). Their vectors, include gnathiid isopods and leeches, respectively. In turtles, Haemogregarina balli has the best-characterized life cycle in the genus. However, no studies in Brazil have suggested a possible vector for any species of Haemogregarina from freshwater turtles. Therefore, in the present study, we provide insights into a leech vector based on specimens found feeding on two species of freshwater turtles, Podocnemis unifilis and Podocnemis expansa, using morphological and molecular data. In 2017 and 2019, freshwater turtles were collected in Goiás State, Brazil. Hosts were inspected for ectoparasites and leeches were collected from two specimens of P. expansa and nine specimens of P. unifilis. Leeches were subsequently identified as members of the genus Unoculubranchiobdella. Leech histological slides revealed haemogregarine-like structures, similar to post-sporogonic merogony, found near the gills and within the posterior sucker. Molecular analysis of the haemeogregarines resulted in the identification of three species of Haemogregarina: Haemogregarina embaubali, Haemogregarina goianensis, and Haemogregarina brasiliana. Therefore, our findings, based on morphology and DNA data suggest leeches of the genus Unoculubranchiondella as vectors for at least three species of Haemogregarina from Brazilian turtles.


Assuntos
Água Doce , Sanguessugas , Tartarugas , Animais , Tartarugas/parasitologia , Brasil , Água Doce/parasitologia , Sanguessugas/classificação , Sanguessugas/anatomia & histologia , Sanguessugas/parasitologia , Filogenia , Vetores de Doenças , Eucoccidiida/isolamento & purificação , Eucoccidiida/genética , Eucoccidiida/classificação
12.
Open Vet J ; 14(4): 962-972, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38808293

RESUMO

Background: The developmental biology of Kinosternon scorpioides is described, based on the phenotype. This species is important for the flora because they are excellent seed disseminators. In addition, basic embryological information is not yet fully clarified, and this research provides unprecedented information on the chelonian embryology of the Amazonian fauna. Aim: The present study aims to identify the embryology of K. scorpioides in captivity during different periods. Methods: Females were monitored throughout the reproductive cycle, by video monitoring, to identify nests and the presence of newly laid eggs. At regular weekly intervals, embryo samples were collected fixed in a 4% paraformol solution and preserved in 70% alcohol. For the embryonic characterization, we used a stereomicroscope and the scanning electron microscopy method. Results: We describe 15 embryonic stages for a 15-week (105-day) incubation process. Only at 42 days (6th week) was the morphological characterization of a chelonian observed and at the 12th week (Stage XII), the phenotypic characterization of the species K. scorpioides. Conclusion: In view of the evidence, we found that these phases are similar to the other turtles, with structural variations in the appearance and disappearance of structures due to the specific characteristics of the species.


Assuntos
Desenvolvimento Embrionário , Tartarugas , Animais , Tartarugas/embriologia , Feminino , Embrião não Mamífero , Microscopia Eletrônica de Varredura/veterinária
13.
BMC Ecol Evol ; 24(1): 71, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811886

RESUMO

Home range is a fundamental characteristic of an animal natural history. The study of home range provides information on the sites where organisms forage for food, find shelter, or locate mates. Home range size and shape can change throughout the lifespan of an organism, during the year, or across seasons, driven by resource availability and the basic needs for each organism. For freshwater and semi-aquatic turtles, home range is greatly affected by water availability, humidity, and temperature throughout the year, nevertheless demographic factors such age and sex are also important determinants of home range size. In this study we estimated home range and dispersal movements for Kinosternon creaseri, Terrapene yucatana, and Rhinoclemmys areolata in a semi-tropical dry forest in central Yucatán. For a two-year period, turtles were surveyed using hoop traps and visual encounters. Twenty-one individuals (5-8 per species) were equipped with radio transmitters to track them across the landscape. Distances between relocations and home range were compared across species seasons, sex, and interactions of these variables. Monthly average movements were positively correlated with rain in the three species studied. Home range of R. areolata was larger than those of K. creaseri and T. yucatana. Home range of the three studied species were larger during the wet season. Home range overlap index within same species individuals was higher during the rainy than dry season, but overall overlap is low between and within species.


Assuntos
Comportamento de Retorno ao Território Vital , Estações do Ano , Tartarugas , Tartarugas/fisiologia , Animais , Feminino , Masculino , México , Comportamento de Retorno ao Território Vital/fisiologia
14.
Ecotoxicology ; 33(4-5): 425-439, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38700807

RESUMO

Due to their natural history and ecological attributes, turtles are excellent organisms for studies of heavy metal contamination. Turtles have a large geographical distribution, occupy different aquatic habitats, and occupy various trophic levels. The present study investigated mercury bioaccumulation in the carnivorous chelonian Chelus fimbriata (Matamata turtle) and Hg biomagnification in relation to its aquatic food chain in the middle Rio Negro, AM-Brazil. Tissue samples of muscle, carapace and claws were collected from 26 C. fimbriata individuals, as well as collections of autotrophic energy sources found in the turtle's aquatic habitat area. The samples were collected in February-March/2014 and analyzed for THg concentrations and carbon (δ13C) and nitrogen (δ15N) stable isotopes. The highest THg levels were found in claws (3780 ng.g-1), carapace (3622 ng.g-1) and muscle (403 ng.g-1), which were found to be significantly different [F(2.73) = 49.02 p < 0.01]. However, THg concentrations in muscle tissue were below the consumption threshold indicated by the WHO and Brazilian Health Ministry. The average δ13C and δ15N values in Matamata samples were -31.7‰ and 11.9‰, respectively. The principal energy source sustaining the food chain of C. fimbriata was found to be terrestrial shrubs, with smaller contributions from emergent aquatic herbaceous plants and algae, while δ15N values showed its trophic position to be two levels above the autotrophic energy sources. There was a positive correlation between THg and turtle size, while a significant relationship was found between THg and δ15N, showing strong biomagnification in the food chain of C. fimbriata: y = 0.21x + 0.46; r2 = 0.45; p < 0.001, for which the slope presented a value of 0.21.


Assuntos
Monitoramento Ambiental , Cadeia Alimentar , Mercúrio , Tartarugas , Poluentes Químicos da Água , Animais , Tartarugas/metabolismo , Brasil , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Mercúrio/análise , Bioacumulação
15.
Sci Rep ; 14(1): 10827, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734762

RESUMO

The creation of protected areas (PAs) is not always based on science; consequently, some aquatic species may not receive the same level of protection as terrestrial ones. The objective of this study was to identify priority areas for the conservation of chelonians in the Brazilian Amazon basin and assess the contribution of PAs, distinguishing between Full Protection Areas, Sustainable Use Areas, and Indigenous Lands for group protection. The entire species modeling procedure was carried out using Species Distribution Models. Location records were obtained from platforms such as SpeciesLink, GBIF, the Hydroatlas database, and WorldClim for bioclimatic variables adjusted with algorithms like Maximum Entropy, Random Forest, Support Vector Machine, and Gaussian-Bayesian. Indigenous lands cover more than 50% of the distribution areas of chelonian species in the Brazilian Amazon. Protected areas with higher conservation importance (Full Protection Areas and Sustainable Use Areas) hold less than 15% of the combined species distribution. Researchers face significant challenges when making decisions with models, especially in conservation efforts involving diverse taxa that differ significantly from one another within a group of individuals.


Assuntos
Conservação dos Recursos Naturais , Tartarugas , Brasil , Conservação dos Recursos Naturais/métodos , Animais , Biodiversidade , Ecossistema
16.
Environ Sci Pollut Res Int ; 31(25): 37215-37228, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38764087

RESUMO

The present study aimed to report the morphometric and hematological indices and genotoxicity of a free-life population of D'Orbigny's slider turtles (Trachemys dorbigni) living in an urban area in Southern Brazil. For that, 16 specimens were randomly captured in an urban canal that receives irregular releases of wastewater. Biometrics and external visual changes were analyzed, such as turtle shell deformities, and the presence of parasites. Blood samples were collected to evaluate the hematological profile and the presence of micronuclei and other erythrocyte nuclear abnormalities as potential mutagenic and genotoxic effects. Water physicochemical parameters were also measured. Organisms with ectoparasites (31.25%) and small carapace deformations (56.25%) were observed, but maximum carapace length and weight were considered normal for the species according to the literature. The blood profile indicated low hemoglobin and hematocrit and a high number of total leukocytes, particularly eosinophils which characterize parasitic infections. A frequency of 0.12% for the micronucleus was considered basal, but the frequency of other erythrocyte abnormalities was evident, mainly of blebbed nuclei (63.79%), indicating chromosomal damage in the early stage. The results of this study suggest that natural populations of chelonian inhabiting urbanized areas are impacted by anthropogenic activities in the surrounding environment. Furthermore, it provides comprehensive data which can serve as a comparative model for environmental monitoring studies involving turtles.


Assuntos
Tartarugas , Animais , Brasil , Biomarcadores/sangue , Água Doce , Monitoramento Ambiental , Testes para Micronúcleos
17.
Mar Environ Res ; 198: 106491, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657368

RESUMO

Our study aimed to establish reference values for nesting females and compare them with those previously reported to understand olive ridley turtles' health status and contribute to long-term health assessment and monitoring in foraging and nesting areas from the state of Sinaloa, Mexico. In August and September 2018, morphometric data and biochemical profiles were collected from 33 nesting olive ridley turtles from Ceuta Beach Sanctuary (CBS) and 14 foraging female turtles captured at the foraging site, Navachiste Marine Area (NMA). Nesting turtles sampled had greater CCL (65.86 ± 1.70 cm) than those from the foraging area (61.54 ± 1.22) (p < 0.05). Regarding biochemical profiles, post-nesting turtles had higher packed cell volume (PCV), albumin, blood urea nitrogen (BUN), cholesterol, triglycerides, and calcium than turtles from the foraging area (p < 0.05). Phosphorus levels were higher in foraging turtles than in nesting turtles (p = 0.001), while the remaining parameters showed no significant differences. The present study describes for the first time the blood biochemical values of nesting turtles from the Ceuta Beach Sanctuary in southern Sinaloa, Mexico, similar to those of foraging turtles from the north of the state. The significant differences observed between the two analysis groups may be due to the energy reserves and reproductive and nesting activity of the nesting turtles, so the blood biochemistry values described in this study can be used as a standard reference blood value for the olive ridley turtle population of Sinaloa, Mexico.


Assuntos
Comportamento de Nidação , Tartarugas , Animais , Tartarugas/sangue , Tartarugas/fisiologia , México , Feminino , Monitoramento Ambiental , Nitrogênio da Ureia Sanguínea , Valores de Referência , Hematócrito
18.
Environ Sci Pollut Res Int ; 31(22): 31967-31977, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38642227

RESUMO

Marine pollution by trace elements is a global concern due to potential toxicity to species and ecosystems. Copper is a fundamental trace element for many organisms; however, it becomes toxic at certain concentrations. The green turtle (Chelonia mydas) is a good sentinel species, due to its circumglobal distribution, long life cycle, coastal habits when juvenile, and is subject to environmental pollution. Quantifying and comparing copper levels makes it possible to understand the availability of this trace element in nature. During this research, comparisons were made between the levels of copper found in the liver, kidneys, and muscles of 35 turtles, from the United States (Hawaii and Texas), Brazil, and Japan. Copper was found in all specimens. In the liver, animals from Hawaii (91.08 µg g-1), Texas (46.11 µg g-1), and Japan (65.18 µg g-1) had statistically equal means, while those from Brazil (16. 79 µg g-1) had the lowest means. For the kidney, copper means were statistically equal for all Hawaii (3.71 µg g-1), Texas (4.83 µg g-1), Japan (2.47 µg g-1), and Brazil (1.89 µg g-1). In muscle, the means between Texas (0.75 µg g-1) and Japan (0.75 µg g-1) were the same, and the mean for Brazil (0.13 µg g-1) was the lowest. Among the organs, the highest levels of copper were found in the liver (28.33 µg g-1) followed by the kidney (2.25 µg g-1) and with the lowest levels in the muscle (0.33 µg g-1). This is the first study of copper levels among marine vertebrates in distant parts of the globe using similar comparative filters between different locations. Similar levels in turtles from such distant locations may indicate that there is a pantropical pattern of copper distribution in the biota, and that these animals are subject to the process of bioavailability of this metal in the environment and metabolic regulation.


Assuntos
Cobre , Tartarugas , Poluentes Químicos da Água , Animais , Tartarugas/metabolismo , Cobre/análise , Oceano Pacífico , Poluentes Químicos da Água/análise , Oceano Atlântico , Monitoramento Ambiental , Brasil , Fígado/metabolismo , Fígado/química , Rim/química , Japão , Texas
19.
J Helminthol ; 98: e30, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584420

RESUMO

Six species of freshwater turtles dominate the Chaco-Pampa Plain in southern South America and their parasites have been relatively understudied, with most records concentrated in Brazil. Particularly in Argentina, there are only scattered records of parasites for most of the turtles that inhabit the region, leaving a large knowledge gap. The purpose of the present contribution is to increase the knowledge of the internal parasites of six species of freshwater turtles from Argentina, after 15 years of fieldwork, by providing new hosts and additional geographic records for many host-parasite relationships. Some molecular sequences of the studied parasites were provided as a tool for better species identification. We processed 433 stomach and fecal samples from live individuals and visceral and soft tissue samples from 54 dissected turtles collected from a wide range and different ecoregions. We found 6230 helminths belonging to 18 taxa (one cestode, 11 digeneans and six nematodes). Fourteen new parasite-host associations are reported here, and for the first time parasites are recorded for Phrynops williamsi. This work contributes significantly to the knowledge of the parasitofauna in freshwater turtles in Argentina, providing a detailed list of parasites present in each turtle species and reporting molecular characters for future studies.


Assuntos
Helmintos , Parasitos , Tartarugas , Animais , Tartarugas/parasitologia , Helmintos/genética , Água Doce , Brasil
20.
Mol Phylogenet Evol ; 197: 108083, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38679303

RESUMO

Kinosternon is the most speciose genus of extant turtles, with 22 currently recognized species, distributed across large parts of the Americas. Most species have small distributions, but K. leucostomum and K. scorpioides range from Mexico to South America. Previous studies have found discordance between mitochondrial and nuclear phylogenies in some kinosternid groups, with the current taxonomy following the nuclear-based results. Herein, based on extended molecular, geographic, and taxonomic sampling, we explore the phylogeographic structure and taxonomic limits for K. leucostomum and the K. scorpioides group and present a fossil-calibrated nuclear time tree for Kinosternon. Our results reveal contrasting differentiation patterns for the K. scorpioides group and K. leucostomum, despite overlapping distributions. Kinosternon leucostomum shows only shallow geographic divergence, whereas the K. scorpioides group is polyphyletic with up to 10 distinct taxa, some of them undescribed. We support the elevation of K. s. albogulare and K. s. cruentatum to species level. Given the deep divergence within the genus Kinosternon, we propose the recognition of three subgenera, Kinosternon, Cryptochelys and Thyrosternum, and the abandonment of the group-based classification, at least for the K. leucostomum and K. scorpioides groups. Our results show an initial split in Kinosternon that gave rise to two main radiations, one Nearctic and one mainly Neotropical. Most speciation events in Kinosternon occurred during the Quaternary and we hypothesize that they were mediated by both climatic and geological events. Additionally, our data imply that at least three South American colonizations occurred, two in the K. leucostomum group, and one in the K. scorpioides group. Additionally, we hypothesize that discordance between mitochondrial and nuclear phylogenetic signal is due to mitochondrial capture from an extinct kinosternine lineage.


Assuntos
Filogenia , Filogeografia , Tartarugas , Animais , Tartarugas/classificação , Tartarugas/genética , América do Sul , Núcleo Celular/genética , DNA Mitocondrial/genética , Análise de Sequência de DNA , Tipagem de Sequências Multilocus , Variação Genética , Teorema de Bayes
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