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1.
Dis Aquat Organ ; 145: 111-117, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196281

RESUMO

The swim bladder inflates early after fish hatching via its interconnection with the digestive tract (ductus pneumaticus). This interconnection may serve as a portal to foreign particles, including bacteria, causing deficiencies in primary swim bladder inflation. We histologically examined 134 African annual killifish (genus Nothobranchius) with secondary loss of swim bladder function ('belly sliders'). We demonstrate that these fish lost the ability of air regulation in their swim bladders likely due to Mycobacterium spp. infection at an individual-specific age. Nearly all examined belly sliders had thickened swim bladder walls, and their swim bladder was filled with material containing mycobacteria, cell debris, young monocytic cells and phagocyting macrophages. Mycobacterial infection was restricted to the swim bladder in juveniles, where mycobacteria likely enter the host through the ductus pneumaticus. Infection in adults was systemic and mycobacteria were present in all examined organs. Presence of mycobacteria in the epithelial lining and submucosal layers of the digestive tract of adults suggests that it may also serve as the entrance site of infection. We suspect 2 sources of Mycobacterium contamination: dietary (with bloodworms) and/or contaminated hatching substrate. These sources of contamination may be eliminated by use of laboratory dry feed and egg disinfection prior to hatching.


Assuntos
Ciprinodontiformes , Tartarugas , Sacos Aéreos , Animais , Bexiga Urinária
2.
Environ Monit Assess ; 193(8): 498, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34287720

RESUMO

Despite the general lack of studies that use reptiles as bioindicators, the value of freshwater turtles and crocodilians in ecotoxicology has been proven, due to their importance as sentinel species. The aim of this study was to compile information on the use of freshwater turtles and crocodilians as environmental biomonitors of inorganic element contamination. We searched for articles in databases using specific keywords. A total of 104 studies published between the years 1970 and 2020 were collected. We noted a general increase in the number of studies involving turtles and crocodilians during the study time period. The Order Testudines were the subjects of 46% of the analysed publications, and the Order Crocodylia accounted for 54%. Within these studies, we counted 39 species (turtles n = 29 and crocodilians n = 10). Forty chemical elements were evaluated in the analysed articles, of which the majority represented non-essential elements (Hg, Cd, Pb). Although internal organs constituted the main biological matrix chosen for each group (37%), we observed an increase in the use of non-destructive matrices in both groups (scale, blood, tail muscle, carapace). The majority of analysed studies used HNO3 for the sample decomposition, with the majority of analyses being performed using atomic absorption spectroscopy (53%). Mainly blank controls (19%), analyte recovery (18%) and replicates (18%) were used as methods of validating analytical procedures. Furthermore, the studies used certified reference materials, which measure the accuracy of the methods used. We conclude that the increase in the use of aquatic reptiles in environmental monitoring research is mainly due to their ability to reveal integrated changes in ecosystems, aiding in environmental public policy decision-making and effective management plans.


Assuntos
Mercúrio , Tartarugas , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Água Doce , Mercúrio/análise , Poluentes Químicos da Água/análise
3.
J Zoo Wildl Med ; 52(2): 520-528, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130394

RESUMO

In this pilot study, the pharmacokinetics of terbinafine were determined in six apparently healthy red-eared slider turtles (Trachemys scripta elegans) after a single PO administration. Terbinafine suspension (15 mg/kg, once) was administered via gavage tube to all turtles. Blood samples were collected immediately before (time 0) and at 1, 2, 4, 8, 24, and 48 h after drug administration. Plasma terbinafine concentrations were quantified by ultra-performance liquid chromatography-mass spectrometry, and noncompartmental pharmacokinetic analysis was performed. None of the animals showed any adverse responses following terbinafine administration. Mean area under the curve from time 0 to 24 h was 1,213 h × ng/ml (range 319-7,309), mean peak plasma concentration was 201.5 ng/ml (range 45.8-585.3), mean time to maximum plasma concentration was 1.26 h (range 1-4), mean residence time was 7.71 h (range 3.85-14.8), and mean terminal half-life was 5.35 h (range 2.67-9.83). The administration of terbinafine (15 mg/kg, PO) may be appropriate for treatment of select fungal organisms with low minimum inhibitory concentrations in red-eared slider turtles but may require q12h administration even for organisms with low minimum inhibitory concentrations. Multiple-dose studies as well as clinical studies are needed to determine ideal dosages and efficacy.


Assuntos
Antifúngicos/farmacocinética , Terbinafina/farmacocinética , Tartarugas/sangue , Animais , Antifúngicos/sangue , Área Sob a Curva , Feminino , Meia-Vida , Projetos Piloto , Terbinafina/sangue
4.
J Zoo Wildl Med ; 52(2): 538-547, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130396

RESUMO

A recently characterized fungal pathogen, Emydomyces testavorans, has been associated with ulcerative shell disease and significant morbidity in Western pond turtles. Voriconazole is a second-generation triazole antifungal medication that prevents fungal growth through disruption of ergosterol synthesis, causing abnormalities in the fungal cell membrane. Preliminary reports of minimum inhibitory concentrations (MIC) indicate that voriconazole is effective in vitro against E. testavorans. Ultraperformance liquid chromatography was used to measure voriconazole plasma concentrations in blood samples from healthy Western pond turtles after administration of a single SC injection of 10 mg/kg and after multiple doses (10 mg/kg SC q48h for seven doses). The data were analyzed using a naïve pooled approach. Mean (SE) observed time to maximum concentration was 2 (0.18) h for a single dose and 50 (2.2) h for multiple doses; the multiple-dose trial observed mean (SE) maximum concentration was 12.4 (2.2) µg/ml, and observed mean (SE) trough concentration was 1.7 (0.7) µg/ml. Multifocal skin sloughing following the single-dose trial was observed in one turtle and there was a significant increase in polychromatophilic cells amongst the study turtles after the multiple-dose voriconazole trial. No other adverse effects were observed. When voriconazole was administered at 10 mg/kg SC q48h, observed trough plasma concentrations were consistently higher than reported E. testavorans MIC concentrations. Further study is needed to determine the clinical safety and in vivo efficacy of this dose in Western pond turtles.


Assuntos
Antifúngicos/sangue , Tartarugas/sangue , Voriconazol/sangue , Animais , Antifúngicos/farmacocinética , Área Sob a Curva , Esquema de Medicação , Feminino , Meia-Vida , Injeções Subcutâneas , Masculino , Voriconazol/farmacocinética
5.
Environ Pollut ; 284: 117453, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34090252

RESUMO

Antimicrobial resistance has become one of the main public health threats worldwide with anthropogenic activities driving the spread of resistance. Understanding and combatting the spread of resistant bacteria is a top priority for global health institutions, and it is included as one of the main goals of the One Health initiative. Giant tortoises (Chelonoidis spp.), some of the most iconic species on Earth, are widely distributed across the Galapagos archipelago and are thus perfect candidates to test the hypothesis that wildlife species in the Galapagos carry antimicrobial resistant genes (ARGs) associated with human activities. We sampled a total of 200 free-living Galapagos tortoises from western Santa Cruz Island (C. porteri), the most human-populated island of the archipelago, and 70 tortoises (C. vandenburghi) from the isolated Alcedo Volcano on Isabela Island, a natural area with minimal human presence. Fecal samples were analyzed by quantitative PCR for a panel of 21 ARGs conferring resistance for eight antimicrobial classes. We found ARGs in both Santa Cruz and Alcedo Volcano giant tortoises; however, both qualitative and quantitative results showed higher loads of ARGs in tortoises inhabiting the human modified environments of Santa Cruz. Moreover, Santa Cruz tortoises sampled in higher human-modified landscapes (i.e., farmlands and urban areas) presented a higher number of ARGs, antimicrobial classes, and multi-resistant microbiomes than those from less anthropized areas within the same island. Our findings suggest that human activities in Galapagos have a negative impact on ecosystem health through ARG dispersal. This research highlights a new threat for the health and conservation of the unique wildlife of the Galapagos, their ecosystems, and the humans inhabiting this World Heritage Site. Our recommendation to local policy makers is to control and reduce the use of antibiotics in both human and animal health, thus helping enforce antimicrobial regulations.


Assuntos
Microbiota , Tartarugas , Animais , Animais Selvagens , Antibacterianos , Farmacorresistência Bacteriana , Equador , Humanos
6.
J Exp Biol ; 224(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34096569

RESUMO

The respiratory system of chelonians needs to function within a mostly solid carapace, with ventilation depending on movements of the flanks. When submerged, inspiration has to work against hydrostatic pressure. We examined breathing mechanics in Trachemys scripta while underwater. Additionally, as the respiratory system of T. scripta possesses a well-developed post-pulmonary septum (PPS), we investigated its role by analyzing the breathing mechanics of lungs with and without their PPS attached. Static compliance was significantly increased in submerged animals and in animals with and without their PPS, while removal of the PPS did not result in a significantly different static compliance. Dynamic compliance was significantly affected by changes in volume and frequency in every treatment, with submergence significantly decreasing dynamic compliance. The presence of the PPS significantly increased dynamic compliance. Submersion did not significantly alter work per ventilation, but caused minute work of breathing to be much greater at any frequency and ventilation level analyzed. Lungs with or without their PPS did not show significantly different work per ventilation when compared with the intact animal. Our results demonstrate that submersion results in significantly altered breathing mechanics, increasing minute work of breathing greatly. The PPS was shown to maintain a constant volume within the animal's body cavity, wherein the lungs can be ventilated more easily, highlighting the importance of this coelomic subdivision in the chelonian body cavity.


Assuntos
Imersão , Tartarugas , Animais , Pulmão , Respiração , Mecânica Respiratória
7.
J Zoo Wildl Med ; 52(2): 604-609, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130403

RESUMO

This study aimed to evaluate intraocular pressure (IOP) estimates in healthy eyes of Caretta caretta using rebound tonometry in comparison with applanation tonometry. Twenty-three healthy C. caretta (housed at the Marine Turtle Research Center) without preexisting ophthalmic disease were enrolled in the study. IOP measurements were obtained by the same ophthalmologist, with the turtle in ventral recumbency between 2:30 p.m. and 4:30 p.m., using a rebound tonometer (RT; TonoVet) in dog calibration mode, and after topical anesthesia, an applanation tonometer (AT; Tono-Pen) in both eyes. The average of three readings per instrument was used for analysis. The agreement between the two tonometers was assessed by Bland-Altman analysis and intraclass correlation coefficient (ICC). Moreover, differences in IOP between the two tonometers were analyzed using the Mann-Whitney test. Moderate agreement was found between the two tonometers (ICC, 0.663; 95% confidence interval, 0.206-0.857). The median, Q1, and Q3 IOP obtained with AT (6.2, 4.7, and 9.1 mm Hg) were significantly lower (P = 0.001) than that obtained with RT (9.7, 8.3, and 11.6 mm Hg). It was not possible to obtain an instrument automatically generated mean of four values with AT because of retraction of the globe by the animals, and IOP measurement was unsuccessful in 7 eyes. In conclusion, IOP readings from the RT were statistically higher than those from the AT. RT proved to be more feasible because of the light, short-lasting contact with the cornea.


Assuntos
Pressão Intraocular/fisiologia , Tonometria Ocular/veterinária , Tartarugas/fisiologia , Animais , Tonometria Ocular/instrumentação , Tonometria Ocular/métodos
8.
J Zoo Wildl Med ; 52(2): 610-617, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130404

RESUMO

Blood fatty acid profiles can indicate an animal's wild-type diet composition and fatty acid status, but have not been reported in sea turtles. Newer technologies allow for fatty acid profiles from very small (less than three drops) samples of whole blood. This study examined whole blood fatty acid profiles of presumably healthy, neritic, juvenile, wild green (Chelonia mydas) (n = 9; 6 males, 3 females) and Kemp's ridley (Lepidochelys kempii) (n = 8; 6 males, 2 females) turtles from North Carolina, USA. Saturated fatty acids, which can be synthesized de novo, consisted primarily of 16:0, although green turtle blood had a higher proportion of 18:0 (P < 0.001) than Kemp's ridleys, while Kemp's ridley blood had higher proportions of 17:0 (P = 0.007), 20:0 (P = 0.03), 22:0 (P= 0.002), and 24:0 (P < 0.001) as compared with green turtles. Total monounsaturated w7 fatty acids, which can be synthesized de novo or may be diet derived, were higher in Kemp's ridleys and predominantly in the form of 16:1 and 18:1w7 fatty acids. Kemp's ridley blood had more than double the relative proportion of 16:1w7 as compared with green turtles (P= 0.03). Green turtles had higher levels of 18:2w6 than Kemp's ridleys (P= 0.02). In both turtle species, 20:4w6 was detected, despite predicted low dietary proportions, suggesting bioconversion from precursors. Finally, green turtles had higher levels of 18:3w3 compared with Kemp's ridleys, while Kemp's ridleys had higher proportions of 20:5w3 compared with green turtles (P < 0.001, = 0.007, respectively). Whole blood fatty acid profiles generally correlate to previous work with lipid depots, supporting the use of this less invasive methodology to advance the understanding of fatty acid nutrition of sea turtles. These data can be used to assess and guide nutrition and health programs for sea turtles under human care.


Assuntos
Animais Selvagens/sangue , Ácidos Graxos/sangue , Tartarugas/sangue , Animais , Feminino , Masculino , Especificidade da Espécie , Tartarugas/genética
9.
J Zoo Wildl Med ; 52(2): 704-709, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130414

RESUMO

Spotted turtles (Clemmys guttata) are an endangered species and are commonly encountered in the pet trade and in many zoological collections across the United States, yet peer-reviewed published reference intervals (RI) for common clinicopathologic tests are unavailable for this species. The objectives of this study were to calculate partial RI for routine hematology, biochemistry, and electrophoretic analyses, as well as to perform an initial comparison of capillary zone electrophoresis (CZE) and agarose gel electrophoresis (AGE) in this species. A single blood sample was obtained from a single collection of 32 apparently healthy captive spotted turtles weighing at least 100 g and was submitted for standard hematologic and biochemistry analyses, as well as electrophoresis via CZE and AGE methods. Partial RI were calculated for corresponding analytes for each type of testing. While CZE and AGE protein fractions were found to have good correlation, some significant differences were observed, reinforcing that RI should be reported with the specific method used for their determination. The spotted turtle electrophoretograms were distinctly different from those previously reported from turtles in the same taxonomic family, including differences in the number and relative prominence of protein fractions.


Assuntos
Proteínas Sanguíneas/química , Eletroforese em Gel de Ágar/veterinária , Eletroforese Capilar/veterinária , Tartarugas/sangue , Animais , Animais de Zoológico , Contagem de Eritrócitos , Feminino , Hematologia , Contagem de Leucócitos/veterinária , Masculino , Minerais/sangue , Valores de Referência
10.
Biol Lett ; 17(6): 20210167, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34102073

RESUMO

Animals with temperature-dependent sex determination (TSD) respond to thermal cues during early embryonic development to trigger gonadal differentiation. TSD has primarily been studied using constant temperature incubations, where embryos are exposed to constant male- or female-producing temperatures, and these studies have identified genes that display sex-specific expression in response to incubation temperature. Kdm6b, a histone demethylase gene, has received specific attention as it is among the initial genes to respond to incubation temperature and is necessary for testis development. Interestingly, Kdm6b retains an intron when eggs are incubated at a constant male-producing temperature, but the role of thermal variability in this developmental process is relatively understudied. Species with TSD regularly experience thermal cues that fluctuate between male- and female-producing temperatures throughout development but it is unclear how Kdm6b responds to such variable temperatures. In this study, we investigate temperature-sensitive splicing in Kdm6b by exposing embryos to male- and female-producing thermal conditions. We show a rapid decrease in levels of the intron retaining transcript of Kdm6b upon exposure to female-producing conditions. These results demonstrate that, under ecologically relevant conditions, temperature-sensitive splicing can differentially regulate genes critical to TSD.


Assuntos
Processos de Determinação Sexual , Tartarugas , Animais , Feminino , Gônadas , Íntrons , Masculino , Processos de Determinação Sexual/genética , Temperatura
11.
Mar Pollut Bull ; 169: 112574, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34119959

RESUMO

Beaches in southern Brazil have substantial marine debris and strandings of dead juvenile green turtles (Chelonia mydas). This study investigates associations by quantifying marine debris (1) ingested among new (<40 cm curved carapace length; CCL) and older (≥40 cm CCL) juvenile C. mydas recruits; (2) concentrations on beach transects; and then (3) selective ingestion by C. mydas. Among 40 C. mydas (2014-2015), 93% had ingested debris, with smaller individuals having proportionally more. Sheet-like and hard plastics were the most frequently ingested, and commonly concentrated on beach transects. Estuarine beach transects had more debris than those facing the ocean. Selectivity analyses revealed all C. mydas avoided white miscellaneous debris and straws, while smaller conspecifics selected clear sheet-like plastics and avoided coloured ones. The results reiterate a need for long-term reforms to regional waste disposal and short-term initiatives encouraging social awareness to avoid key plastics and reduce ingestion by C. mydas.


Assuntos
Tartarugas , Animais , Brasil , Ingestão de Alimentos , Plásticos
12.
Science ; 372(6546)2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083458

RESUMO

Scott et al (Reports, 27 November 2020, p. 1086) bring much-needed attention to species conservation by demonstrating heterozygote superiority among translocated tortoises. However, we believe that their recommended heterozygosity decision rule risks taking conservation genomics backward. We argue that their advice could misguide conservation management aimed at establishing viable populations, and that it can be improved by also assessing the genetic load.


Assuntos
Tartarugas , Animais , Heterozigoto , Tartarugas/genética
13.
Science ; 372(6546)2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083459

RESUMO

Hansson et al argue that our main finding could provide an overly simplistic metric for maximizing genetic rescue. They agree that translocating the most genetically diverse individuals led to a large increase in translocated tortoise survival, but recommend instead moving individuals that have low genetic load and the greatest representation of metapopulation diversity. Their recommendation is based on specific model assumptions and fitness effects that are often unknown and are not generalizable to many endangered species applications.


Assuntos
Tartarugas , Animais , Espécies em Perigo de Extinção , Heterozigoto , Humanos , Tartarugas/genética
14.
Science ; 372(6546)2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083460

RESUMO

Scott et al (Reports, 27 November 2020, p. 1086) suggest, on the basis of conclusions obtained from a desert tortoise reintroduction program, that higher genomic heterozygosity should be used to identify individuals for successful translocation. I contend that this recommendation is questionable given these relocated tortoises' unknown origin, their high mortality, insufficient data on resident tortoises and other components of fitness, and potential allelic dropout.


Assuntos
Tartarugas , Animais , Heterozigoto , Humanos , Tartarugas/genética
15.
Science ; 372(6546)2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083461

RESUMO

Hedrick brings up several potential concerns that he feels challenge or limit our main finding. Hedrick does not comment on our empirical results, but rather argues that several factors may confound or invalidate our conclusion. Many of these concerns focus on unknown ecological aspects of the translocated tortoises, but we believe there is no reason to conclude that they bias the results or interpretation as presented in our original paper.


Assuntos
Tartarugas , Animais , Heterozigoto , Masculino , Tartarugas/genética
16.
Food Res Int ; 145: 110414, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34112417

RESUMO

This study aimed to explore nutritional compositions and proteomics of soft-shelled turtle (SST) egg, as well as identify potential antidiabetic oligopeptides with α-glucosidase inhibitory property. Results revealed that SST egg is a promising source of highly nutritious proteins and minerals (54.64% and 5.81% of dry matter, respectively). Further proteomic analysis showed SST egg proteins contained at least 9 protein families, such as transferrin/iron binding protein and immunoregulation-related protein. Hydrolysis by different enzymes, especially papain, remarkably increased α-glucosidase inhibitory activity and scavenging activity for ABTS, DPPH, hydroxyl and oxygen radicals of SST egg proteins. Peptides from papain hydrolysate were fractionated using ultrafiltration followed by reverse phase chromatography, and 16 peptides were identified in the most active fraction by LC-QTOF-MS/MS. Molecular docking revealed that 14 of these peptides could easily dock into the substrate-binding pocket and/or inhibitor binding sites of α-glucosidase with the docking score below -150 kcal/mol, indicating their potential α-glucosidase inhibitory properties. The five most abundant oligopeptides with potent interaction with α-glucosidase were further synthesized, and oligopeptides HNKPEVEVR, ARDASVLK and SGTLLHK strongly inhibited the activity of α-glucosidase (IC50 of 56, 195 and 289 µmol/L, respectively). Therefore, oligopeptides from enzymatic hydrolysate of SST egg protein exhibit potential antidiabetic activity, making it a promising functional food ingredient.


Assuntos
Tartarugas , alfa-Glucosidases , Animais , Simulação de Acoplamento Molecular , Oligopeptídeos , Proteômica , Espectrometria de Massas em Tandem
17.
Zootaxa ; 4991(1): 1-35, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34186737

RESUMO

A tuberculated species of turtle leech is indigenous to the Great Dismal Swamp and environs of northeastern North Carolina, and differs from other known species of Placobdella. This study of hundreds of specimens for more than a decade documents its unexpected taxonomic complexity. In fact, this seemingly innocuous leech undergoes radical transformations in terms of morphology and behaviour, each adapted to a different phase of its life cycle. Biological observations reveal a progressive darkening with age which imposes taxonomic uncertainties. Furthermore, some commonly used characters are found to be unsound for taxonomic diagnosis in that they do not occur in all individuals of this species. The primary objective of this paper is a comprehensive description of this Albemarle turtle leech. The question is then asked, what distinguishes it from allied species? Toward this end, a formal taxonomic diagnosis is proposed based on details of the proboscis complex and crop-related tuberculation. This species is allied to the northern P. rugosa (Verrill, 1874) or its southern counterpart P. multilineata Moore, 1953. However, synonymy to either of these forms is problematical due to inadequacy of type descriptions. Nonetheless, in view of habitat similarity the Albemarle leech is provisionally identified as P. multilineata pending comparable studies of variability and development of other tuberculated Placobdella.


Assuntos
Sanguessugas , Tartarugas , Animais , Sanguessugas/anatomia & histologia , Sanguessugas/classificação , North Carolina , Especificidade da Espécie , Tartarugas/parasitologia , Áreas Alagadas
18.
BMC Genomics ; 22(1): 346, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33985425

RESUMO

BACKGROUND: Transcriptomic data has demonstrated utility to advance the study of physiological diversity and organisms' responses to environmental stressors. However, a lack of genomic resources and challenges associated with collecting high-quality RNA can limit its application for many wild populations. Minimally invasive blood sampling combined with de novo transcriptomic approaches has great potential to alleviate these barriers. Here, we advance these goals for marine turtles by generating high quality de novo blood transcriptome assemblies to characterize functional diversity and compare global transcriptional profiles between tissues, species, and foraging aggregations. RESULTS: We generated high quality blood transcriptome assemblies for hawksbill (Eretmochelys imbricata), loggerhead (Caretta caretta), green (Chelonia mydas), and leatherback (Dermochelys coriacea) turtles. The functional diversity in assembled blood transcriptomes was comparable to those from more traditionally sampled tissues. A total of 31.3% of orthogroups identified were present in all four species, representing a core set of conserved genes expressed in blood and shared across marine turtle species. We observed strong species-specific expression of these genes, as well as distinct transcriptomic profiles between green turtle foraging aggregations that inhabit areas of greater or lesser anthropogenic disturbance. CONCLUSIONS: Obtaining global gene expression data through non-lethal, minimally invasive sampling can greatly expand the applications of RNA-sequencing in protected long-lived species such as marine turtles. The distinct differences in gene expression signatures between species and foraging aggregations provide insight into the functional genomics underlying the diversity in this ancient vertebrate lineage. The transcriptomic resources generated here can be used in further studies examining the evolutionary ecology and anthropogenic impacts on marine turtles.


Assuntos
Tartarugas , Animais , Sequência de Bases , Especificidade da Espécie , Transcriptoma , Tartarugas/genética
19.
Sci Total Environ ; 788: 147790, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34034177

RESUMO

Harmful algal blooms (HABs), caused primarily by nutrient input from agricultural runoff, are a threat to freshwater systems worldwide, and are further predicted to increase in size, frequency, and intensity due to climate change. HABs occur annually in the Western Basin of Lake Erie (Ohio, USA), and these blooms become toxic when dominated by cyanobacteria that produce the liver toxin microcystin. Although we are making substantial inroads toward understanding how microcystin affects human health, less is known about effects of microcystin on wildlife exposed to HABs. Wetland-associated songbirds (barn swallows, Hirundo rustica, and red-winged blackbirds, Agelaius phoeniceus) and reptiles (Northern watersnakes, Nerodia sipedon, and painted turtles, Chrysemys picta) were sampled from wetlands exposed to chronically high microcystin levels due to a prolonged HAB event, and from unexposed, control wetlands. Physiological stress levels and several measures of immune functioning were compared between the HAB-exposed and control populations. Physiological stress levels, measured as heterophil:lymphocyte ratios, were higher in barn swallows, red-winged blackbirds, and Northern watersnakes exposed to a chronic HAB compared to unexposed, control individuals, but painted turtles did not differ in physiological stress levels between HAB-exposed and control individuals. Neither barn swallows nor red-winged blackbirds differed in immune functioning between populations, but HAB-exposed watersnakes had higher bactericidal capacity than control snakes, and HAB-exposed painted turtles had lower bactericidal capacity than control turtles. These results suggest that even when HABs do not cause direct mortality of exposed wildlife, they can potentially act as a physiological stressor across several taxa, and furthermore may compromise immune functioning in some species.


Assuntos
Aves Canoras , Tartarugas , Animais , Proliferação Nociva de Algas , Ohio , Áreas Alagadas
20.
Mar Pollut Bull ; 168: 112395, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33991990

RESUMO

During the monitoring of Caretta caretta nests on the island of Linosa, 30 unhatched eggs from four nests were collected to study the presence of phthalates in their three components (shell, yolk, and albumen). Four phthalates, namely diethyl (DEP), dibutyl (DBP), di-(2-ethylhexyl) (DEHP), and dioctyl (DOTP) phthalic acid esters (PAE), which are widely used as additives in plastics, were detected in all egg components. The most frequently found phthalate was DBP, followed by DEHP in eggshell and yolk. Dimethyl- (DMP) and butylbenzyl-phthalate (BBP) were below the limits of detection for all samples. The high total phthalate recorded in the yolk suggests that contamination could arise by vitellogenesis. PERMANOVA analysis (p = 0.01) confirmed significant differences in the PAEs contamination profiles in the eggs from the four nests. This study confirms the negative impact of plastic related compounds posing questions about the potential adverse effects on organisms and their conservation status.


Assuntos
Ácidos Ftálicos , Tartarugas , Animais , Dibutilftalato , Ilhas , Mar Mediterrâneo , Ácidos Ftálicos/análise , Plásticos
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