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1.
PLoS One ; 15(7): e0235537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614926

RESUMO

Recent studies describe the use of UAVs in collecting blow samples from large whales to analyze the microbial and viral community in exhaled air. Unfortunately, attempts to collect blow from small cetaceans have not been successful due to their swimming and diving behavior. In order to overcome these limitations, in this study we investigated the application of a specific sampling tool attached to a UAV to analyze the blow from small cetaceans and their respiratory microbiome. Preliminary trials to set up the sampling tool were conducted on a group of 6 bottlenose dolphins (Tursiops truncatus) under human care, housed at Acquario di Genova, with approximately 1 meter distance between the blowing animal and the tool to obtain suitable samples. The same sampling kit, suspended via a 2 meter rope assembled on a waterproof UAV, flying 3 meters above the animals, was used to sample the blows of 5 wild bottlenose dolphins in the Gulf of Ambracia (Greece) and a sperm whale (Physeter macrocephalus) in the southern Tyrrhenian Sea (Italy), to investigate whether this experimental assembly also works for large whale sampling. In order to distinguish between blow-associated microbes and seawater microbes, we pooled 5 seawater samples from the same area where blow samples' collection were carried out. The the respiratory microbiota was assessed by using the V3-V4 region of the 16S rRNA gene via Illumina Amplicon Sequencing. The pooled water samples contained more bacterial taxa than the blow samples of both wild animals and the sequenced dolphin maintained under human care. The composition of the bacterial community differed between the water samples and between the blow samples of wild cetaceans and that under human care, but these differences may have been mediated by different microbial communities between seawater and aquarium water. The sperm whale's respiratory microbiome was more similar to the results obtained from wild bottlenose dolphins. Although the number of samples used in this study was limited and sampling and analyses were impaired by several limitations, the results are rather encouraging, as shown by the evident microbial differences between seawater and blow samples, confirmed also by the meta-analysis carried out comparing our results with those obtained in previous studies. Collecting exhaled air from small cetaceans using drones is a challenging process, both logistically and technically. The success in obtaining samples from small cetacean blow in this study in comparison to previous studies is likely due to the distance the sampling kit is suspended from the drone, which reduced the likelihood that the turbulence of the drone propeller interfered with successfully sampling blow, suggested as a factor leading to poor success in previous studies.


Assuntos
Cetáceos/microbiologia , Microbiota , Sistema Respiratório/microbiologia , Aeronaves , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Golfinho Nariz-de-Garrafa/microbiologia , Análise por Conglomerados , Análise de Componente Principal , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Robótica , Baleias/microbiologia
2.
Dis Aquat Organ ; 140(1): 103-108, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32701066

RESUMO

Photographs collected during a 23 yr photo-identification study in the Moray Firth were examined to assess the prevalence, type and severity of vertebral deformations present in bottlenose dolphin Tursiops truncatus calves. Fifteen cases of presenting spinal anomalies (scoliosis, kyphosis, lordosis and combinations thereof) of variable severity were identified in 7.4% of all known calves from the population. Thirteen of the 15 anomalies were either manifest from birth or acquired from an early age, as ascertained from longitudinal sightings histories of their mothers. Most afflicted calves died during early development or shortly after maternal separation. However, 3 survived to adulthood and persist in the population to date, in addition to 2 dependent infants whose fate remains to be established. At 15+ yr of age, the oldest surviving individual was remarkably one of the most severe cases identified, highlighting the ability of these delphinids for adaptation to such gross structural deformities. The aetiology of the observed conditions could be attributed to a range of causative factors that may have implications for the well-being and health of this North Sea coastal dolphin population, a topic which merits further investigation.


Assuntos
Golfinho Nariz-de-Garrafa , Cifose/veterinária , Lordose/veterinária , Animais , Privação Materna , Escócia
3.
J Zoo Wildl Med ; 51(2): 443-447, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549577

RESUMO

Melioidosis is an emerging infectious disease of humans and animals caused by the bacterium Burkholderia pseudomallei and endemic in tropical regions, principally Southeast Asia and northern Australia. In September 2017, after Hurricane Maria impacted the Dolphin Discovery facility in the Federation of St. Kitts and Nevis, a juvenile male bottlenose dolphin (Tursiops truncatus) died within 96 hr of presenting with acute anorexia, lethargy, and respiratory distress. Histopathology demonstrated necrohemorrhagic bronchopneumonia, necrotizing hepatitis, splenitis, and lymphadenitis, with intralesional Gram-negative bacilli. B. pseudomallei was confirmed by bacteriological culture and DNA sequencing. This case emphasizes the challenges of melioidosis diagnosis, the importance of awareness for both early detection and efficacious treatment, and recognition in tropical regions where it has been either not reported or underreported. To the authors' knowledge, this is the first case of cetacean melioidosis in the Caribbean Islands, an often severe and fatal disease with increasing prevalence on the American continent.


Assuntos
Golfinho Nariz-de-Garrafa , Burkholderia pseudomallei/isolamento & purificação , Melioidose/veterinária , Animais , Animais de Zoológico , Tempestades Ciclônicas , Diagnóstico Diferencial , Masculino , Melioidose/diagnóstico , Melioidose/microbiologia , São Cristóvão e Névis
4.
J Zoo Wildl Med ; 51(2): 448-454, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549578

RESUMO

A freshly dead juvenile bottlenose dolphin (Tursiops truncatus), recovered from the waters near Sand Key, Clearwater, FL, was imaged postmortem using computed tomography and magnetic resonance imaging prior to conventional necropsy. The pattern of imaging findings in the brain was compatible with severe multifocal meningoencephalitis with intralesional necrosis and/or hemorrhage, and the pattern of imaging findings in the lungs was compatible with severe multifocal bronchopneumonia. The subsequent investigation included necropsy, histology, culture, and molecular diagnostics and demonstrated disseminated coinfection of dolphin morbillivirus and Aspergillus fumigatus. This is the first report documenting the cross-sectional imaging findings of this important cetacean comorbidity and demonstrates advances in modern, cooperative investigations of marine mammal mortality events.


Assuntos
Aspergilose/veterinária , Aspergillus fumigatus/isolamento & purificação , Golfinho Nariz-de-Garrafa , Coinfecção/veterinária , Infecções por Morbillivirus/veterinária , Morbillivirus/isolamento & purificação , Animais , Animais Selvagens , Aspergilose/diagnóstico , Aspergilose/microbiologia , Coinfecção/diagnóstico , Coinfecção/microbiologia , Coinfecção/virologia , Imagem por Ressonância Magnética/veterinária , Infecções por Morbillivirus/diagnóstico , Infecções por Morbillivirus/virologia , Tomografia Computadorizada por Raios X/veterinária
5.
Emerg Infect Dis ; 26(7): 1610-1612, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32568058

RESUMO

We characterized novel coronaviruses detected in US bottlenose dolphins (BdCoVs) with diarrhea. These viruses are closely related to the other 2 known cetacean coronaviruses, Hong Kong BdCoV and beluga whale CoV. A deletion in the spike gene and insertions in the membrane gene and untranslated regions were found in US BdCoVs (unrelated to severe acute respiratory syndrome coronavirus 2).


Assuntos
Golfinho Nariz-de-Garrafa/virologia , Infecções por Coronavirus/veterinária , Diarreia/veterinária , Gammacoronavirus/classificação , Gammacoronavirus/genética , Animais , Infecções por Coronavirus/virologia , Diarreia/virologia , Gammacoronavirus/isolamento & purificação , Gammacoronavirus/fisiologia , Genes Virais , Genoma Viral , Mutação , Filogenia , Deleção de Sequência , Glicoproteína da Espícula de Coronavírus/genética , Proteínas da Matriz Viral/genética
6.
Sci Total Environ ; 732: 139125, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32438143

RESUMO

Aquatic contamination, oil spills in particular, could lead to the accumulation of antibiotic resistance by promoting selection for and/or transfer of resistance genes. However, there have been few studies on antibiotic resistance in marine mammals in relation to environmental disturbances, specifically oil contaminations. Here we initiated a study on antibiotic resistance bacteria in bottlenose dolphins Tursiops truncatus in relation to oil contamination following the 2010 BP Oil Spill in the northern Gulf of Mexico. Bacterial communities and antibiotic resistance prevalence one year after the 2010 BP Oil Spill were compared between Barataria Bay (BB) and Sarasota Bay (SB) by applying the rarefaction curve method, and (generalized) linear mixed models. The results showed that the most common bacteria included Vibrio, Shewanella, Bacillus and Pseudomonas. The prevalence of antibiotic resistance was high in the bacterial isolates at both bays. Though bacterial diversity did not differ significantly among water or dolphin samples, and antibiotic resistance did not differ significantly among water samples between the two bays, antibiotic resistance and multi-drug resistance in dolphin samples was significantly higher in the BB than in the SB, mainly attributed to the resistance to E, CF, FEP and SXT. We also found sulfamethoxazole-trimethoprim-resistant Stenotrophomonas maltophilia the first time in the natural aquatic environment. The higher antibiotic resistance in the dolphins in BB is likely attributed to 2010 BP Oil Spill as we expected SB, a more urbanized bay area, would have had higher antibiotic resistance based on the previous studies. The antibiotic resistance data gathered in this research will fill in the important data gaps and contributes to the broader spatial-scale emerging studies on antibiotic resistance in aquatic environments.


Assuntos
Golfinho Nariz-de-Garrafa , Animais , Bactérias , Farmacorresistência Bacteriana , Golfo do México , Poluição por Petróleo
7.
PLoS One ; 15(5): e0233658, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442214

RESUMO

Most commonly, animal communication systems are driven by shared call repertoires, with some individual distinctiveness encoded as a byproduct of voice cues. We provide evidence that bottlenose dolphins produce both individually distinctive whistles, and a shared whistle type. A stereotyped whistle contour (termed the group whistle) is shared by five bottlenose dolphins that have lived, worked, and traveled together for at least 21 years. These five dolphins are members of a group of eight dolphins that work as a specialized team for the Navy Marine Mammal Program. Each dolphin is routinely recorded during periods when an individual is isolated from the others in above ground pools as part of their routine training. Each of the eight dolphins has an individually distinctive signature whistle. In addition, at least five of these dolphins share a distinct non-signature whistle type. This shared whistle contour was produced an average of 22.4% +/- 9.0% of the time during periods in which individuals were isolated. During these isolations the signature whistle was produced an average of 42.9% +/- 11.9% of the time. This is consistent with decades of signature whistle research. A group of 10 naïve observers rated the similarity of the different whistle contours. The observers rated the group whistle contour produced by all five dolphins as highly similar (P < 0.01). Their ratings further showed that the signature whistles of the five dolphins were very different (P < 0.01). These findings were further supported by discriminant function analyses. That said, the shared whistle contours still exhibited individual differences which may allow conspecifics to identify the producer even when a whistle contour is shared among multiple dolphins. This is the first in-depth analysis of a non-signature whistle type shared among multiple conspecifics.


Assuntos
Golfinho Nariz-de-Garrafa/psicologia , Vocalização Animal , Animais , Feminino , Individualidade , Masculino , Comportamento Social , Espectrografia do Som/métodos , Estereotipagem
8.
Dis Aquat Organ ; 139: 69-79, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32351237

RESUMO

Dolphin tattoo lesions are superficial non-raised skin lesions caused by poxviruses. Their presentation can vary but typical lesions in bottlenose dolphins are circular to ovoid with concentric rings of black stippling. These lesions have at times been suggested as an indicator of overall dolphin health and welfare. This study explored the effect of water temperature on the extent of tattoo lesions in 25 dolphins, along with established hematological health parameters and food consumption. Study animals consisted of 9 males and 16 females with dolphin tattoo lesions ranging in age from 2 to 45 yr. A significant decrease (p < 0.01) in extent and appearance of tattoo lesions was documented following increase in water temperature from 21-24°C (70-75°F) to 25.5-26.5°C (78-80°F). Reduction in tattoo lesions could be noted as early as 2-3 wk following water temperature increase. Marked reduction to complete resolution of tattoo lesions was reproducibly seen 5-6 wk post temperature increase. Food consumption following temperature increase was variable: decrease in intake was noted in 48% of dolphins, increase in intake in 52%. Routine blood parameters (complete blood count, serum chemistry panel, fibrinogen, erythrocyte sedimentation rate) remained within normal limits. A significant increase (p < 0.05) in extent and appearance of tattoo lesions was documented in 3 dolphins as early as 4-5 wk following a decrease in water temperature from 26.1°C (79°F) to 21°C (70°F). Water temperature is a key environmental parameter affecting cetacean pox ('tattoo') lesions in bottlenose dolphins. The absence of changes in hematological parameters along with lack of correlation between extent of pox lesions and food intake indicates that dolphin tattoo lesions are not an appropriate indicator of overall health.


Assuntos
Golfinho Nariz-de-Garrafa , Tatuagem , Animais , Feminino , Masculino , Temperatura , Água
9.
Proc Biol Sci ; 287(1924): 20192944, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32228413

RESUMO

Synchronous displays are hallmarks of many animal societies, ranging from the pulsing flashes of fireflies, to military marching in humans. Such displays are known to facilitate mate attraction or signal relationship quality. Across many taxa, synchronous male displays appear to be driven by competition, while synchronous displays in humans are thought to be unique in that they serve a cooperative function. Indeed, it is well established that human synchrony promotes cooperative endeavours and increases success in joint action tasks. We examine another system in which synchrony is tightly linked to cooperative behaviour. Male bottlenose dolphins form long-lasting, multi-level, cooperative alliances in which they engage in coordinated efforts to coerce single oestrus females. Previous work has revealed the importance of motor synchrony in dolphin alliance behaviour. Here, we demonstrate that allied dolphins also engage in acoustic coordination whereby males will actively match the tempo and, in some cases, synchronize the production of their threat vocalization when coercing females. This finding demonstrates that male dolphins are capable of acoustic coordination in a cooperative context and, moreover, suggests that both motor and acoustic coordination are features of coalitionary behaviour that are not limited to humans.


Assuntos
Acústica , Comportamento Animal , Golfinho Nariz-de-Garrafa/fisiologia , Comportamento Cooperativo , Vocalização Animal , Animais , Feminino , Masculino
10.
PLoS One ; 15(4): e0230769, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32259832

RESUMO

Bottlenose dolphins (Tursiops truncatus) are long-lived mammals that can develop chronic aging-associated conditions similar to humans, including metabolic syndrome. Initial studies suggest that these conditions may be attenuated in dolphins using a modified fish diet. Serum metabolomics, fatty acid panels, and blood-based health indices were compared between 20 dolphins on a modified, 50% wild-type diet (50% mullet, 25% capelin, and 25% squid and/or herring) and 10 dolphins on a baseline diet (75% capelin and 25% squid and/or herring). Blood samples were collected at Months 0, 1, 3 and 6. Dolphins on the modified diet had lower insulin (7.5 ± 4.0 and 14.8 ± 14.0 µIU/ml, P = 0.039), lower cholesterol (160 ± 26 and 186 ± 24 mg/dl, P = 0.015) and higher hematocrit (46 ± 3 and 44 ± 3%, P = 0.043) by Month 1 compared to controls. Dolphins with anemia (hemoglobin ≤ 12.5 g/dl, n = 6) or low-normal hemoglobin (12.5-13.5 g/dl, n = 3) before placed on the modified diet had normal hemoglobin concentrations (> 13.5 g/dl) by Month 3. The modified diet caused a significant shift in the metabolome, which included 664 known metabolites. Thirty prioritized metabolites at Months 1 and 3 were 100% predictive of dolphins on the modified diet. Among 25 prioritized lipids, 10 (40%) contained odd-chain saturated fatty acids (OCFAs); C15:0 was the highest-prioritized OCFA. Increased dietary intake of C15:0 (from 1.3 ± 0.4 to 4.5 ± 1.1 g/day) resulted in increased erythrocyte C15:0 concentrations (from 1.5 ± 0.3 to 5.8 ± 0.8 µg/ml, P < 0.0001), which independently predicted raised hemoglobin. Further, increasing age was associated with declining serum C15:0 (R2 = 0.14, P = 0.04). While higher circulating OCFAs have been previously associated with lower risks of cardiometabolic diseases in humans, further studies are warranted to assess potential active roles of OCFAs, including C15:0, in attenuating anemia.


Assuntos
Anemia/etiologia , Anemia/metabolismo , Golfinho Nariz-de-Garrafa/sangue , Golfinho Nariz-de-Garrafa/metabolismo , Ácidos Graxos/metabolismo , Peixes/sangue , Peixes/metabolismo , Metaboloma/fisiologia , Animais , Colesterol/metabolismo , Dieta/métodos , Feminino , Masculino , Síndrome Metabólica/genética , Síndrome Metabólica/metabolismo
11.
PLoS One ; 15(3): e0230319, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32168368

RESUMO

Passive acoustic monitoring (PAM) is a powerful method to study the occurrence, movement and behavior of echolocating odontocetes (toothed whales) in the wild. However, in areas occupied by more than one species, echolocation clicks need to be classified into species. The present study investigated whether the echolocation clicks produced by small, at-risk, resident sympatric populations of Indian Ocean humpback dolphin (Sousa plumbea) and Indo-Pacific bottlenose dolphin (Tursiops aduncus) in Menai Bay, Zanzibar, East Africa, could be classified to allow species specific monitoring. Underwater sounds of S. plumbea and T. aduncus groups were recorded using a SoundTrap 202HF in January and June-August 2015. Eight acoustic parameters, i.e. -10 dB duration, peak, centroid, lower -3 and lower -10 dB frequencies, and -3 dB, -10 dB and root-mean-squared bandwidth, were used to describe and compare the two species' echolocation clicks. Statistical analyses showed that S. plumbea clicks had significantly higher peak, centroid, lower -3 and lower -10 dB frequencies compared to T. aduncus, whereas duration and bandwidth parameters were similar for the two species. Random Forest (RF) classifiers were applied to determine parameters that could be used to classify the two species from echolocation clicks and achieved 28.6% and 90.2% correct species classification rates for S. plumbea and T. aduncus, respectively. Both species were classified at a higher rate than expected at random, however the identified classifiers would only be useful for T. aduncus monitoring. The frequency and bandwidth parameters provided most power for species classification. Further study is necessary to identify useful classifiers for S. plumbea. This study represents a first step in acoustic description and classification of S. plumbea and T. aduncus in the western Indian Ocean region, with potential application for future acoustic monitoring of species-specific temporal and spatial occurrence in these sympatric species.


Assuntos
Golfinho Nariz-de-Garrafa/fisiologia , Golfinhos/fisiologia , Ecolocação/fisiologia , Vocalização Animal/fisiologia , Animais , Ecossistema , Oceano Índico , Oceano Pacífico , Especificidade da Espécie , Tanzânia
12.
Dis Aquat Organ ; 138: 17-27, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32052791

RESUMO

Pulmonary function testing was performed in 3 bottlenose dolphins Tursiops truncatus (1 female and 2 males) under managed care during a 2 yr period to assess whether these data provide diagnostic information about respiratory health. Pulmonary radiographs and standard clinical testing were used to evaluate the pulmonary health of each dolphin. The female dolphin (F1) had evidence of chronic pulmonary fibrosis, and 1 male (M2) developed pneumonia during the study. Pulmonary function data were collected from maximal respiratory efforts in water and from spontaneous breaths while beached. From these data, the flow-volume relationship, the flow measured between 25 and 75% of the expired vital capacity (mid forced expiratory flow, FEF25%-75%), and the percent of the vital capacity (VC) at the peak expiratory flow (%VCPEF), were evaluated and compared with the diagnostic assessment. For maximal respiratory manoeuvres in water, there were no differences in FEF25%-75% or %VCPEF, and the flow-volume relationship showed a consistent pattern for F1. Additionally, FEF25%-75% and %VCPEF decreased by 27 and 52%, respectively, and the flow-volume relationship showed clear flow limitations with emerging disease in M2. While spontaneously breathing on land, M2 also showed a 49% decrease in %VCPEF and changes in the flow-volume relationship, indicating flow limitations following the development of pneumonia. Based on these preliminary results, we suggest that pulmonary function testing should be given more attention as a non-invasive and possibly adjunctive diagnostic tool to evaluate lung health of dolphins under managed care and in the wild.


Assuntos
Golfinho Nariz-de-Garrafa , Animais , Feminino , Pulmão , Masculino
13.
Aust Vet J ; 98(3): 92-95, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32030727

RESUMO

A captive adult female bottlenose dolphin presented with stillbirth. The placenta appeared oedematous. No other gross lesions were evident in the placenta or the stillborn calf. Histopathology revealed mild multifocal placentitis and foetal encephalitis. Brucella sp. was isolated from lung, liver, spleen and kidney. Sequence and phylogenetic analysis demonstrated this organism to be most similar to Brucella ceti sequence type (ST) 27. Brucella sp. DNA was detected in formalin-fixed paraffin-embedded placenta and brain by real-time PCR using primers targeting the IS711 gene. Immunohistochemical staining revealed Brucella sp. antigen in placental inflammation. This is the first report of isolation of Brucella sp. from a marine mammal in the Southern Hemisphere and the first report of marine Brucella-associated disease in Australia.


Assuntos
Golfinho Nariz-de-Garrafa , Brucelose/veterinária , Animais , Austrália , Brucella , Feminino , Filogenia , Gravidez , Natimorto/veterinária
14.
Vet Surg ; 49(4): 741-747, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31916617

RESUMO

OBJECTIVE: To evaluate the efficacy of stents to distribute pressure when incorporated into tension-relieving sutures. STUDY DESIGN: An in vitro study and case report. ANIMAL: One common bottlenose dolphin (Tursiops truncates). METHODS: Three novel silicone stents, a traditional stent, and a control were tested in vitro by using a suture simulator. Stent surface area was measured by using a pressure mapping sensor. Pressure was derived from the measured surface area and the downward force of the suture simulator. Novel silicone stents were also used in the closure of an incision in a bottlenose dolphin. RESULTS: No difference was found in surface area or pressure among the three silicone stents (adjusted P > .05). Silicone stents yielded an average, 2.69 cm2 more surface area and 842.37 kPa less pressure compared with the control as well as 1.67 cm2 more surface area and 110.67 kPa less pressure compared with the traditional stent. The traditional stent yielded 1.02 cm2 more surface area and 731.7 kPa less pressure compared with the control. Incision site and silicone stent assessment performed postoperatively revealed no obvious pressure necrosis. CONCLUSION: Stents improved distribution of suture pressure, and novel silicone stents were more effective compared with traditional stents. Novel silicone stents appear to have preliminary clinical success in vivo. CLINICAL SIGNIFICANCE: Our study provides evidence that stents effectively help distribute suture pressure, and their incorporation might minimize the risk of suture pressure necrosis. Novel silicone stents should be integrated into tension-relieving suture patterns when closing wounds and incisions, particularly in aquatic animals.


Assuntos
Golfinho Nariz-de-Garrafa/cirurgia , Necrose/prevenção & controle , Pressão/efeitos adversos , Stents/veterinária , Suturas/veterinária , Animais , Feminino , Técnicas In Vitro , Necrose/etiologia
15.
Vet Radiol Ultrasound ; 61(2): 215-226, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31899939

RESUMO

Reproductive success is vital in sustaining free-ranging and managed bottlenose dolphin (Tursiops truncatus) populations. Ultrasonography is an invaluable, non-invasive tool in assessing the fetomaternal unit in humans and animals, including dolphins and horses. The purpose of this prospective longitudinal cohort study was to develop a protocol for fetomaternal ultrasonographic monitoring in dolphins and to report normal measurements and descriptive findings correlated with a positive outcome. From 2010 to 2017, serial ultrasonographic evaluations of 12 healthy dolphins were performed over the course of 16 pregnancies. A total of 203 ultrasound examinations were included in the study. Several metrics were accurate in predicting fetal age. Fetal biparietal diameter (BPD), thoracic width in dorsal and transverse planes, thoracic height in a sagittal plane, aortic diameter, and blubber thickness all demonstrated high correlation with gestational age (r > 0.94, P < .00001). Regional uteroplacental thickness significantly increased with each trimester (range 0.22-0.40 cm; P < .00011 cranial uterus, P < .00057 mid, and P < .000011 caudal). Lung:liver mean pixel intensity was 2.57 ± 0.46 (95% confidence interval 2.47-2.67). Ultrasonographic characteristics of normal pregnancy in dolphins are described and an equation for prediction of parturition date in Tursiops is reported: days to parturition = 348.16 - (26.03 × BPD(cm)) (R2  = 0.99). Future applications of these normal data will help identify in utero abnormalities indicative of fetal morbidity, and improve understanding of reproductive failure in wild and managed populations.


Assuntos
Golfinho Nariz-de-Garrafa , Prenhez , Ultrassonografia Pré-Natal/veterinária , Animais , Estudos de Coortes , Feminino , Desenvolvimento Fetal , Estudos Longitudinais , Gravidez , Estudos Prospectivos , Útero
16.
Aquat Toxicol ; 218: 105371, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790939

RESUMO

Harmful algal bloom (HAB) toxins have severe negative impacts on marine mammals, particularly for Florida bottlenose dolphins (Tursiops truncatus) which frequently experience mass mortality events. Dolphins on the Florida Atlantic coast inhabit a region endemic to two HAB species, Karenia brevis and Pyrodinium bahamense, which produce the neurotoxins brevetoxin (PbTx) and saxitoxin (STX), respectively. Although toxic HABs and associated dolphin mortality events have been reported from this region, there is a lack of available data necessary for comparing toxin exposure levels between bloom ('exposed') conditions and non-bloom ('baseline') conditions. Here we present a 10-year dataset of PbTx and STX concentrations detected in dolphins stranding in this region, and compare the toxin loads from HAB-exposed dolphins to those detected in dolphins recovered in the absence of a HAB. We analyzed liver tissue samples from dead-stranded dolphins (n = 119) recovered and necropsied between 2002-2011, using an enzyme-linked immunosorbent assay (ELISA) modified for use with mammalian tissues. For dolphins recovered during baseline conditions, toxin-positive samples ranged in concentration from 0.27 to 1.2 ng/g for PbTx and from 0.41 to 1.9 ng/g for STX. For K. brevis-exposed dolphins, concentrations of up to 12.1 ng PbTx/g were detected, and for P. bahamense-exposed dolphins, concentrations of up to 9.9 ng STX/g were detected. Baseline PbTx values were similar to those reported in other regions where K. brevis blooms are more frequent and severe, but HAB-exposed PbTx values were considerably lower relative to these other regions. Since no baseline STX dolphin data exist for any region, our data serve as a first step towards establishing reference STX values for potential dolphin mortality events associated with STX-producing blooms in the future. This study demonstrates that although HABs in eastern Florida are only infrequently associated with dolphin mortalities, the presence of toxins in these animals may pose significant health risks in this region.


Assuntos
Golfinho Nariz-de-Garrafa/metabolismo , Monitoramento Ambiental/métodos , Proliferação Nociva de Algas , Toxinas Marinhas/análise , Oxocinas/análise , Saxitoxina/análise , Poluentes Químicos da Água/análise , Animais , Dinoflagelados/crescimento & desenvolvimento , Ensaio de Imunoadsorção Enzimática , Florida , Fígado/química , Fígado/metabolismo , Toxinas Marinhas/toxicidade , Oxocinas/toxicidade , Rios/química , Saxitoxina/toxicidade , Poluentes Químicos da Água/toxicidade
17.
Gen Comp Endocrinol ; 286: 113323, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733207

RESUMO

Providing for infants nutritionally via lactation is one of the hallmarks of mammalian reproduction, and infants without motivated mothers providing for them are unlikely to survive. Mothers must maintain regular contact with infants both spatially and temporally while utilising their environment to forage, avoid threats and find shelter. However, mothers can only do this and maximise their reproductive success with some degree of co-operation from infants, despite their developing physical and cognitive capabilities. The neuropeptide hormone oxytocin (OT) triggers proximity-seeking behaviour and acts in a positive feedback loop across mother-infant bonds, stimulating appropriate pro-social behaviour across the pair. However, data on infant OT levels is lacking, and it is unclear how important infants are in maintaining mother-infant associations. The bottlenose dolphin (Tursiops truncatus) is a mammalian species that is fully physically mobile at birth and has multi-year, but individually variable, lactation periods. We investigated OT concentrations in mother-infant pairs of wild individuals compared to other age and reproductive classes. An ELISA to detect OT in dolphin plasma was successfully validated with extracted plasma. We highlight a statistical method for testing for parallelism that could be applied to other ELISA validation studies. OT concentrations were consistently elevated in calves up to at least 4 years of age with lactating mothers (12.1 ±â€¯0.9 pg/ml), while all mothers (4.5 ±â€¯0.4 pg/ml) had OT concentrations comparable to non-lactating individuals (5.9 ±â€¯0.5 pg/ml). Concentrations within infants were individually variable, and may reflect the strength of the bond with their mother. The OT system likely provides a physiological mechanism for motivating infants to perform behaviours that prevent long-term separation from their mothers during this crucial time in their life history. Elevated infant OT has also been linked to energetic and developmental advantages which may lead to greater survival rates. Environmental or anthropogenic disturbances to OT release can occur during bond formation or can disrupt the communication methods used to reinforce these bonds via OT elevation. Variation in OT expression in infants, and its behavioural and physiological consequences, may explain differences in reproductive success despite appropriate maternal behaviour expression.


Assuntos
Comportamento Materno/fisiologia , Ocitocina/metabolismo , Reprodução/fisiologia , Animais , Golfinho Nariz-de-Garrafa , Feminino , Humanos , Masculino
18.
Theriogenology ; 142: 92-103, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585227

RESUMO

The physiological demands of pregnancy inevitably result in changes of both biochemical and hematological parameters as the fetus develops. Alterations in blood parameters have been observed to shift according to both trimester and species, to support fetal physiological needs and maternal basal requirements. Establishing normal reference ranges for each stage in gestation is important to facilitate diagnosis of underlying health concerns and prevent over-diagnosing abnormalities. Despite bottlenose dolphins (Tursiops truncatus) being one of the most highly studied cetaceans, the blood profile changes occurring as a result of pregnancy have not been previously described. A retrospective analysis was performed from blood samples obtained from 42 successful pregnancies from 20 bottlenose dolphins in a managed population over 30 years. Samples were compared to non-pregnant states and among trimesters of pregnancy. Blood profile fluctuations occurred throughout gestation, however significant alterations predominantly occurred between the 2nd and 3rd trimester. Hematological changes from the 2nd to the 3rd trimester included a decrease in lymphocytes, decrease in platelet count, and hemoconcentration with increased hematocrit and hemoglobin. Biochemical changes in the 3rd trimester included significant reductions in ALKP (alkaline phosphatase), ALT (alanine aminotransferase) and AST (aspartate aminotransferase) with significant increases observed in albumin, globulins, total protein, cholesterol, triglycerides and CO2. It's important to note that despite significant shifts occurring between the 2nd and 3rd trimester, there was no significant change in platelets, hematocrit, hemoglobin, lymphocytes or CO2 between non-pregnant and 3rd trimester blood samples. The normal reference ranges for each trimester established herein, will enable future identification of abnormalities occurring during pregnancy and help improve our understanding of factors potentially influencing a failed or successful pregnancy outcome.


Assuntos
Contagem de Células Sanguíneas/veterinária , Golfinho Nariz-de-Garrafa/sangue , Prenhez , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Glicemia , Proteínas Sanguíneas , Nitrogênio da Ureia Sanguínea , Golfinho Nariz-de-Garrafa/fisiologia , Cálcio/sangue , Dióxido de Carbono/sangue , Cloretos/sangue , Creatinina/metabolismo , Feminino , L-Lactato Desidrogenase/sangue , Lipídeos/sangue , Fósforo/sangue , Potássio/sangue , Gravidez , Prenhez/sangue , Estudos Retrospectivos , Sódio/sangue , Ácido Úrico/sangue
19.
Environ Res ; 180: 108886, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31708171

RESUMO

Due to their long life-span and top trophic position, odontocetes can accumulate high concentrations of mercury (Hg) in their tissues. This study measured the concentration of total Hg (THg) in the blubber and skin of bottlenose dolphins (Tursiops truncatus) that stranded along the Florida (FL) panhandle and Louisiana (LA) coasts and investigated the relationship between total Hg (THg) concentration and sex, body length, age, stranding location, diet/trophic position (δ13C and δ15N, respectively), and foraging habitat (δ34S). Additionally, we compared models using body length and age as explanatory variables to determine which was a better predictor of THg concentration. In both tissues, sex was not an influential predictor of THg concentration and there was a positive relationship between body length/age and THg concentration (p < 0.001). Florida dolphins had greater mean blubber and skin THg concentrations compared to LA dolphins (p < 0.001). There was a modest improvement in model fit when age was used in place of body length. δ13C, δ15N, and δ34S differed between stranding locations and together with age were significant predictors of THg concentrations (R2 = 0.52, P < 0.001). Florida dolphins were δ13C enriched compared to LA dolphins (p < 0.001) and THg concentrations were positively correlated with δ13C (R2 = 0.22, p < 0.001). Our results demonstrate spatial variability in THg concentrations from stranded bottlenose dolphins from the northern Gulf of Mexico; however, future research is required to understand how fine-scale population structuring of dolphins within FL and LA impacts THg concentrations, particularly among inshore (bay, sound, and estuary) stocks and between inshore and offshore stocks, as variations in biotic and abiotic conditions can influence both stable isotope ratios and THg concentrations.


Assuntos
Golfinho Nariz-de-Garrafa , Mercúrio , Poluentes Químicos da Água , Tecido Adiposo/química , Animais , Carga Corporal (Radioterapia) , Monitoramento Ambiental , Florida , Golfo do México , Louisiana , Mercúrio/análise , Pele/química
20.
Anim Reprod Sci ; 212: 106248, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864493

RESUMO

The use of cryopreserved dolphin spermatozoa facilitates the exchange of genetic material between aquatic parks and makes spermatozoa accessible to laboratories for studies to further our understanding of marine mammal reproduction. Sperm cryopreservation in the bottlenose dolphin (Tursiops truncatus) has been developed for the exchange of gametes within the ex situ population. The aim of this study was to develop an effective method for refrigeration of bottlenose dolphin spermatozoa diluted in a commercial extender (BTS). In Experiment 1, the effect of temperature (5 compared with 15 °C) on sperm quality was evaluated during 7 days of storage at 100 × 106 spermatozoa/ml. In Experiment 2, the effect of the storage concentration (100 × 106 compared with 20 × 106 spermatozoa/ml) on sperm quality was assessed during 7 days of storage at 5 °C. In Experiment 1, total motility (including % of rapid sperm) was greater at 5 than 15 °C. When the effect of storage concentration was evaluated (Experiment 2), total motility and ALH were greater at the higher storage concentration (100 × 106 spermatozoa/ml). For both experiments, values for viability, acrosome integrity, and normal morphology variables were consistent throughout the 7 days of refrigeration. In Experiment 3, a microbiological study was performed to evaluate the effect of the refrigeration temperature and days of storage on bacterial growth. The results of microbiological analysis indicated there was Staphylococcus aureus in some samples, however, there was no effect of temperature or days of refrigeration. In conclusion, bottlenose dolphin semen can be refrigerated for a short to medium period of storage and there is maintenance of functionality of sperm when stored at 100 × 106 spermatozoa/ml at 5 °C.


Assuntos
Golfinho Nariz-de-Garrafa/fisiologia , Refrigeração , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Temperatura Baixa , Criopreservação/veterinária , Masculino , Fatores de Tempo
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