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1.
Viruses ; 14(9)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36146656

RESUMO

Cetacean poxviruses (CePVs) cause 'tattoo' skin lesions in small and large cetaceans worldwide. Although the disease has been known for decades, genomic data for these poxviruses are very limited, with the exception of CePV-Tursiops aduncus, which was completely sequenced in 2020. Using a newly developed pan-pox real-time PCR system targeting a conserved nucleotide sequence located within the Monkeypox virus D6R gene, we rapidly detected the CePV genome in typical skin lesions collected from two Peruvian common bottlenose dolphins (Tursiops truncatus) by-caught off Peru in 1993. Phylogenetic analyses based on the sequencing of the DNA polymerase and DNA topoisomerase genes showed that the two viruses are very closely related to each other, although the dolphins they infected pertained to different ecotypes. The poxviruses described in this study belong to CePV-1, a heterogeneous clade that infects many species of dolphins (Delphinidae) and porpoises (Phocoenidae). Among this clade, the T. truncatus CePVs from Peru were more related to the viruses infecting Delphinidae than to those detected in Phocoenidae. This is the first time that CePVs were identified in free-ranging odontocetes from the Eastern Pacific, surprisingly in 30-year-old samples. These data further suggest a close and long-standing pathogen-host co-evolution, resulting in different lineages of CePVs.


Assuntos
Golfinho Nariz-de-Garrafa , Chordopoxvirinae , Toninhas , Poxviridae , Animais , Golfinho Nariz-de-Garrafa/genética , Cetáceos , Chordopoxvirinae/genética , DNA Topoisomerases/genética , DNA Polimerase Dirigida por DNA/genética , Peru/epidemiologia , Filogenia , Toninhas/genética , Poxviridae/genética , Reação em Cadeia da Polimerase em Tempo Real
2.
Proc Biol Sci ; 289(1980): 20221090, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35919995

RESUMO

Extreme asymmetry of the skull is one of the most distinctive traits that characterizes toothed whales (Odontoceti, Cetacea). The origin and function of cranial asymmetry are connected to the evolution of echolocation, the ability to use high-frequency sounds to navigate the surrounding environment. Although this novel phenotype must arise through changes in cranial development, the ontogeny of cetacean asymmetry has never been investigated. Here we use three-dimensional geometric morphometrics to quantify the changes in degree of asymmetry and skull shape during prenatal and postnatal ontogeny for five genera spanning odontocete diversity (oceanic dolphins, porpoises and beluga). Asymmetry in early ontogeny starts low and tracks phylogenetic relatedness of taxa. Distantly related taxa that share aspects of their ecology overwrite these initial differences via heterochronic shifts, ultimately converging on comparable high levels of skull asymmetry. Porpoises maintain low levels of asymmetry into maturity and present a decelerated rate of growth, probably retained from the ancestral condition. Ancestral state reconstruction of allometric trajectories demonstrates that both paedomorphism and peramorphism contribute to cranial shape diversity across odontocetes. This study provides a striking example of how divergent developmental pathways can produce convergent ecological adaptations, even for some of the most unusual phenotypes exhibited among vertebrates.


Assuntos
Ecolocação , Toninhas , Animais , Evolução Biológica , Filogenia , Crânio , Baleias
3.
Dis Aquat Organ ; 149: 145-154, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35735234

RESUMO

Harbour porpoises are widely distributed in the North Atlantic and represent the most abundant cetacean species in the North and Baltic Seas. Spontaneous neoplasms are relatively rarely reported in cetaceans, and only little is known about neoplasia in harbour porpoises. Thus, archival material was reviewed for spontaneous neoplasms in harbour porpoises recorded during post-mortem examinations between 1999 and 2018. Neoplasms were identified in 7 adult porpoises: 6 animals originating from the North and Baltic Seas and investigated as part of German and Dutch systematic health monitoring programs, and 1 porpoise from Greenlandic waters. The tumours were of different histogenetic origins and further characterised by histology and immunohistochemistry. One individual had a neoplasia in the digestive tract (adenocarcinoma, n = 1); 4 animals, in the genital tract (Sertoli cell tumour, n = 1; genital leiomyoma/fibroleiomyoma, n = 3); and 2 porpoises, in endocrine organs (adrenal adenoma, n = 2). This is the first report of an adenocarcinoma in the liver, a testicular Sertoli cell tumour and adrenocortical adenomas in harbour porpoises. The cause of the tumorigenesis in examined cases remains undetermined. The involvement of endogenous factors, including mutation of cell cycle regulating genes, such as the tumour-suppressor gene p53, cannot be ruled out. The aetiopathogenetic significance of exogenous factors, such as infectious agents like liver flukes or anthropogenic factors, including persistent organic pollutants, should be the subject of future investigations.


Assuntos
Adenocarcinoma , Phocoena , Toninhas , Tumor de Células de Sertoli , Neoplasias Testiculares , Adenocarcinoma/veterinária , Animais , Fígado/metabolismo , Masculino , Tumor de Células de Sertoli/veterinária , Neoplasias Testiculares/veterinária
4.
Arch Microbiol ; 204(7): 361, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35662380

RESUMO

This is a culture-dependent study with the objective of pure culturing and characterizing pathogenic bacteria from the blowhole, lung, stomach and fecal samples of a neonatal crucially endangered Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) that died 27 days after birth. Bacteria were inoculated using a swab onto blood and MacConkey agar plates and representative isolates were identified through 16S rRNA gene sequence analysis. A total of three Clostridium perfringens type C strains from the fecal samples were isolated. Toxin genes, including cpa, cpb and cpb2, were detected by PCR amplification, whereas the etx, iap and cpe genes were not detected. Biofilm formation of the three strains was then examined. Only one strain was capable of biofilm formation. In addition, isolates showed strong resistance against the antibiotics amikacin (3/3), erythromycin (1/3), gentamicin (3/3), streptomycin (3/3), and trimethoprim (3/3), while sensitivity to ampicillin (3/3), bacitracin (3/3), erythromycin (2/3), penicillin G (3/3), and tetracycline (3/3). The results suggested C. perfringens type C could have contributed to the death of this neonatal porpoise.


Assuntos
Toninhas , Animais , Antibacterianos/farmacologia , Bactérias/genética , Biofilmes , Clostridium perfringens/genética , Eritromicina , Genótipo , Toninhas/genética , Toninhas/microbiologia , RNA Ribossômico 16S/genética
5.
Sci Prog ; 105(2): 368504221103776, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35635263

RESUMO

Cetaceans inhabit oceans throughout the world. Four specific odontocetes, namely Cuvier's beaked whale (Ziphius cavirostris), Indo Pacific finless porpoise (Neophocaena phocaenoides), pygmy sperm whale (Kogia breviceps), and dwarf sperm whale (Kogia sima), have occasionally been found stranded along Thailand's coastal waters (the Andaman Sea and the Gulf of Thailand). Although shared haplotypes of each species for many locations have been found, and some species have revealed genetic structure through haplotype networks, cetaceans in Thai waters have never been investigated in terms of comparing haplotypes to those that have existed before. Herein, we have illustrated the matrilineally phylogeographic relationships among worldwide populations through Bayesian Phylogenetic tree computations using Markov Chain Monte Carlo (MCMC) and Median-Joining Networks (MJNs). Unique haplotypes of the control region mitochondrial DNA of Thai odontocetes were found for all species. Moreover, a high degree of worldwide haplotype diversity (hd) above 0.8 among the four species was detected, while the lowest degree of nucleotide diversity (π) was observed in the Indo Pacific finless porpoise (1.12% ± 0.184%). An expansion of the effective female population size worldwide of three odontocete species was detected using Bayesian Skyline Reconstruction, but this did not include the Indo Pacific finless porpoise. Because Thai seas are located within the Indo Polynesian province, where this biodiversity hotspot exists, we speculate that these odontocetes may also inhabit specific habitats within the Malay Peninsula and Thailand's territorial waters. Therefore, closer attention and monitoring of these cetacean populations will be necessary for future conservation efforts.


Assuntos
Toninhas , Baleias , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Feminino , Filogenia , Toninhas/genética , Tailândia
6.
Sci Total Environ ; 838(Pt 1): 155954, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35580683

RESUMO

Habitats of freshwater cetaceans are under increasing threats of deterioration globally. A complete understanding of long-term variations of habitat configurations is therefore critical. Poyang Lake in China contains a large and stable population of the Yangtze finless porpoise, a critically endangered freshwater cetacean species. However, constant water decline and intensified human activities in the lake since 2000 have led to uncertainty for porpoise conservation. We address this issue via remote sensing and hydrodynamic modeling of nine environmental variables during different seasons over the past two decades. The MaxEnt model was used to extrapolate changes in likely habitat configurations of the porpoise, and MARXAN algorithms delineated habitat protection priorities in different seasons. Results illustrate that flow velocity, water depth, Chl-a concentration, distance to grassland and boats greatly affect the porpoise distribution. Shifts in these environmental variables can lead to significant habitat decreases in all seasons. In particular, unstable hydrological regimes may force the porpoises to live in habitats with lower water depths for suitable flow velocity conditions in the dry season, and habitats are increasingly infringed by grassland and mudflats. High protection priority areas such as the northern channel and the estuaries of the tributaries urgently need long-term systematic and targeted surveys of ecosystem functionality and flexible management of anthropogenic activities. Combining remote sensing with hydrodynamic and species distribution models can also assist in understanding the situation of other aquatic species.


Assuntos
Toninhas , Animais , China , Ecossistema , Hidrologia , Lagos , Água
7.
Sci Total Environ ; 822: 153651, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35124055

RESUMO

Stranding data can provide conservation-valuable information on cetaceans over long time and large space, representing a low-cost but useful approach to monitor these indicator species and their inhabiting environments. Here, we established a national dataset by collating all available records of cetacean strandings (CSs) along >30,000-km coastline of China over seven decades. Between 1950 and 2018, a total of 1763 CSs were recorded across 36 cetacean species from eight families. Importantly, 30.5% of the recorded species are currently recognized as threatened levels on the IUCN Red List. In quantity, Odontocete species accounted for 89.9% of total CSs. In 1763 CSs, 91.8% were events of single individual. Furthermore, 31.9% and 42.4% were events of alive and dead animals, respectively. The number of CSs increased gradually from 1950 to 2018, and more rapidly between 1990 and 2018. CSs occurred in all months, while a seasonal pattern could be observed with 38.5% reports between March and June. The most commonly recorded species were finless porpoises (Neophocaena spp., n = 492) and Indo-Pacific humpback dolphin (Sousa chinensis, n = 291). The highest number of CSs (n = 478) was documented in Hong Kong, while the greatest species richness (n = 28) and the highest stranding density (24.6 CSs per 100-km coastline) were observed in Taiwan. Several CS hotspots were identified in the southern and eastern China, while hotspots differed among taxonomic categories. To conclude, these findings provided a comprehensive understanding of cetacean communities in the coastal waters of China, which are beneficial for improving further research, conservation, and management on cetaceans.


Assuntos
Golfinhos , Toninhas , Animais , Cetáceos , China , Hong Kong , Humanos
8.
J Paediatr Child Health ; 58(6): 978-984, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35060658

RESUMO

AIM: To develop a model for a paediatric sepsis registry for use in emergency care settings. A regional study, in the UK, was undertaken to identify the most basic registry components which are desirable and feasible using the concept of a minimum viable product. METHODS: Two-round survey of clinicians using a modified Delphi methodology in conjunction with a regional data collection project in three paediatric emergency departments across London. RESULTS: The survey identified 34 desirable information items to be included in a registry. Fifteen of 34 items are currently feasible from our experience of data collection. CONCLUSION: The development of a multi-centre paediatric sepsis registry sepsis may have several benefits but is currently extremely limited primarily because of technological fragmentation within our Health Service. Our findings have important implications for researchers wishing to plan sepsis surveillance programmes, locally and internationally.


Assuntos
Serviços Médicos de Emergência , Toninhas , Sepse , Animais , Criança , Serviço Hospitalar de Emergência , Humanos , Sistema de Registros , Sepse/diagnóstico
9.
Environ Int ; 159: 107014, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34883460

RESUMO

Harbour porpoises are under pressure from increasing human activities. This includes the detonation of ammunition that was dumped in large amounts into the sea during and after World War II. In this context, forty-two British ground mines from World War II were cleared by means of blasting in the period from 28 to 31 August 2019 by a NATO unit in the German Exclusive Economic Zone within the marine protected area of Fehmarn Belt in the Baltic Sea, Germany. Between September and November 2019, 24 harbour porpoises were found dead in the period after those clearing events along the coastline of the federal state of Schleswig-Holstein and were investigated for direct and indirect effects of blast injury. Health evaluations were conducted including examinations of the brain, the air-filled (lungs and gastrointestinal tract) and acoustic organs (melon, acoustic fat in the lower jaw, ears and their surrounding tissues). The bone structure of the tympano-periotic complexes was examined using high-resolution peripheral quantitative computed tomography (HR-pQCT). In 8/24 harbour porpoises, microfractures of the malleus, dislocation of middle ear bones, bleeding, and haemorrhages in the melon, lower jaw and peribullar acoustic fat were detected, suggesting blast injury. In addition, one bycaught animal and another porpoise with signs of blunt force trauma also showed evidence of blast injury. The cause of death of the other 14 animals varied and remained unclear in two individuals. Due to the vulnerability and the conservation status of harbour porpoise populations in the Baltic Sea, noise mitigation measures must be improved to prevent any risk of injury. The data presented here highlight the importance of systematic investigations into the acute and chronic effects of blast and acoustic trauma in harbour porpoises, improving the understanding of underwater noise effects and herewith develop effective measures to protect the population level.


Assuntos
Traumatismos por Explosões , Phocoena , Toninhas , Animais , Traumatismos por Explosões/etiologia , Traumatismos por Explosões/veterinária , Explosões , Pulmão , II Guerra Mundial
10.
Environ Sci Technol ; 56(10): 6113-6122, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33851820

RESUMO

Perfluoroalkyl sulfonates (PFSAs), perfluoroalkyl carboxylates (PFCAs), and emerging alternatives and precursors of these compounds were determined in tissues of finless porpoise (Neophocaena asiaeorientalis sunameri) collected from East China Sea in 2009-2010 and 2018-2019. The median hepatic concentrations of emerging poly- and perfluoroalkyl substances (PFASs), including 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA), 8:2 chlorinated polyfluorinated ether sulfonate (8:2 Cl-PFESA), 2,3,3,3-tetrafluoro-2-propanoate (HFPO-DA), and 4,8-dioxa-3H-perfluorononanoate (ADONA) were 16.2, 2.16, < LOQ (limit of quantification) and < LOQ ng/g ww (wet weight), respectively. The concentrations of legacy substances, perfluorooctanesulfonate (PFOS), and perfluorooctanoate (PFOA), were 86.9 and 1.95 ng/g ww, respectively. The liver concentrations of 6:2 Cl-PFESA, HFPO-DA, and perfluorohexanesulfonate (PFHxS) increased with time between 2009-2010 and 2018-2019. Further, concentrations of PFOA showed a declining trend in finless porpoise, whereas PFOS and its precursor (i.e., perfluorooctane sulfonamide [FOSA]) showed an increasing trend with time between 2009-2010 and 2018-2019. Analysis of PFASs in nine different tissues/organs of finless porpoise (i.e., liver, heart, intestine, spleen, kidney, stomach, lung, muscle, and skin) revealed a similar distribution pattern between 6:2 Cl-PFESA and PFOS; however, the tissue distribution patterns differed between HFPO-DA and PFOA. The concentrations of PFAS alternatives in kidney were similar or lower than the prototype compounds PFOS and PFOA (i.e., 8:2 Cl-PFESA < 6:2 Cl-PFESA ≈ PFOS; HFPO-DA < PFOA), implying slow renal excretion of PFAS alternatives as that of legacy PFASs. The estimates of body burdens of PFASs in porpoises suggested comparable accumulation of PFAS alternatives and legacy PFSAs and PFCAs. This study provides novel information on temporal trends and tissue distribution of emerging PFASs in marine mammals in China.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Toninhas , Alcanossulfonatos/análise , Ácidos Alcanossulfônicos/análise , Animais , China , Éter , Éteres , Fluorcarbonetos/análise
11.
Integr Zool ; 17(4): 638-655, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34751496

RESUMO

The stratification of blubber fatty acids (FAs) is a widely used strategy in marine mammals and can be influenced by many factors, including their diet, environmental temperature, and physiological status. There are 3 distinct finless porpoise species/subspecies in Chinese coastal and inland waters in a wide range from 20°N to 40°N. The biochemical stratification of the blubbers of finless porpoises in different regions may provide valuable information for understanding their environmental adaptations. The FA compositions of 4 geographic populations of finless porpoise (FP) collected from the Bohai Gulf, East China Sea, South China Sea, and Yangtze River were therefore analyzed and compared. The blubber FA compositions of finless porpoises were dominated by ΣMUFAs, followed by ΣSFAs and ΣPUFAs, and were generally consistent with those of other cetaceans. The blubber of finless porpoises was significantly stratified with increasing levels of ΣMUFAs and decreasing levels of ΣSFAs and ΣPUFAs from the inner to the outer layers. The 3 marine populations shared more similarities in their FA compositions and stratifications compared to the freshwater porpoises, particularly regarding the PUFAs in the inner layers, which might have been mainly influenced by the diet compositions of marine and freshwater porpoises. Contrary to what was expected, in the 3 marine populations, the SFA and MUFA levels showed opposite correlations (negative and positive, respectively) with habitat temperatures, possibly indicating an adaptation mechanism in finless porpoises characterized by a trade-off between the insulation and fluidity properties of the blubber through the adjustment of the compositions and gradients of MUFAs and SFAs across the blubber depth in response to environmental temperature/latitude changes.


Assuntos
Toninhas , Animais , China , Ácidos Graxos , Água Doce , Toninhas/fisiologia , Rios
12.
J Morphol ; 283(3): 273-286, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34962309

RESUMO

Vertebral morphology has profound biomechanical implications and plays an important role in adaptation to different habitats and foraging strategies for cetaceans. Extant porpoise species (Phocoenidae) display analogous evolutionary patterns in both hemispheres associated with convergent evolution to coastal versus oceanic environments. We employed 3D geometric morphometrics to study vertebral morphology in five porpoise species with contrasting habitats: the coastal Indo-Pacific finless porpoise (Neophocaena phocaenoides); the mostly coastal harbor porpoise (Phocoena phocoena) and Burmeister's porpoise (Phocoena spinipinnis); and the oceanic spectacled porpoise (Phocoena dioptrica) and Dall's porpoise (Phocoenoides dalli). We evaluated the radiation of vertebral morphology, both in size and shape, using multivariate statistics. We supplemented data with samples of an early-radiating delphinoid species, the narwhal (Monodon monoceros); and an early-radiating delphinid species, the white-beaked dolphin (Lagenorhynchus albirostris). Principal component analyses were used to map shape variation onto phylogenies, and phylogenetic constraints were investigated through permutation tests. We established links between vertebral morphology and movement patterns through biomechanical inferences from morphological presentations. We evidenced divergence in size between species with contrasting habitats, with coastal species tending to decrease in size from their estimated ancestral state, and oceanic species tending to increase in size. Regarding vertebral shape, coastal species had longer centra and shorter neural processes, but longer transverse processes, while oceanic species tended to have disk-shaped vertebrae with longer neural processes. Within Phocoenidae, the absence of phylogenetic constraints in vertebral morphology suggests a high level of evolutionary lability. Overall, our results are in accordance with the hypothesis of speciation within the family from a coastal ancestor, through adaptation to particular habitats. Variation in vertebral morphology in this group of small odontocetes highlights the importance of environmental complexity and particular selective pressures for the speciation process through the development of adaptations that minimize energetic costs during locomotion and prey capture.


Assuntos
Golfinhos , Phocoena , Toninhas , Animais , Ecossistema , Filogenia , Toninhas/anatomia & histologia , Coluna Vertebral
13.
Sci Total Environ ; 807(Pt 1): 150782, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34619183

RESUMO

Identifying seasonal high-use habitats and migration corridors is the basis for migratory species conservation. Previous studies have focused on Marine Protected Areas, while freshwater ecosystems, often accompanied by severe hydrological fluctuations, suggest new perspectives for flexible management. Poyang Lake is an essential habitat for the critically endangered Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis, YFP), supporting almost half of their natural population. However, studies on the movement patterns and habitat preferences of YFPs still lack there, preventing potential protected areas' effectiveness. In this study, we conducted 10 surveys for the YFP population in the main body and tributaries of Poyang Lake from October 2018 to August 2020. We used habitat modeling to analyze their seasonal habitat use and the environmental predictors. YFPs showed a seasonal movement pattern consistent with water level fluctuations. They entered the tributaries from the main lake body in low and medium water levels and returned to the main lake during high water level periods. The water depth was the most important environmental variable in each hydrological season that affects YFPs' habitat selection. The suitable water depth was about 4-8 m during the low water level, 6-12 m during the medium water level, and 7-20 m during the high water level. YFPs' 50% core habitats distribution showed noticeable seasonal changes. The proportion of their suitable habitats in the whole lake was relatively low, which was highest during high water level (16.89%), and the weakest during low water level (12.11%). Considering the seasonal movements of the YFPs in the lake, we recommend flexible management measures for their core habitats to alleviate human interference and restore their movement rhythm between the river and the lake, which shed light on protected area management for aquatic animals in such seasonal fluctuating habitats.


Assuntos
Toninhas , Animais , China , Ecossistema , Lagos , Rios , Estações do Ano
14.
Science ; 374(6573): 1332-1333, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34882455
15.
Ecotoxicol Environ Saf ; 226: 112860, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34624534

RESUMO

The Yangtze River exhibits a high biodiversity and plays an important role in global biodiversity conservation. As the world's busiest inland river in regard to shipping, little attention has been paid to underwater noise pollution. In 2017, the underwater noise level in 25 riverside locations along the middle and lower reaches of the Yangtze River mainly at night time were investigated by using passive acoustic monitoring method. Approximately 88% and 40% of the sampled sites exhibit noise levels exceeding the underwater acoustic thresholds of causing responsiveness and temporary threshold shift, respectively, in cetacean. Noise pollution may impose a high impact on fish with physostomous swim bladders and Weberian ossicles, such as silver carp, bighead carp, goldfish and common carp, whereas it may affect fish with physoclistous swim bladders and without Weberian ossicles, such as lake sturgeon and paddlefish, to a lesser extent. Noise levels reductions of approximately 10 and 20 dB were observed in the middle and lower reaches, respectively, of the Yangtze River over the 2012 level. The green development mode of the ongoing construction of green shipping in the Yangtze River Economic Belt, including the development of green shipping lanes, ports, ships and transportation organizations, may account for the alleviated underwater noise pollution. Follow-up noise mitigation endeavors, such as the extension of ship speed restrictions and the study and implementation of the optimal navigation speed in ecologically important areas, are required to further reduce the noise level in the Yangtze River to protect local porpoises and fish.


Assuntos
Carpas , Toninhas , Animais , Biodiversidade , China , Ruído/efeitos adversos , Rios
16.
Sci Rep ; 11(1): 21164, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34707173

RESUMO

Laterality has been reported in many vertebrates, and asymmetrical cerebral hemisphere function has been hypothesized to cause a left-bias in social behavior and a right-bias in feeding behavior. In this paper, we provide the first report of behavioral laterality in free-ranging finless porpoises, which seems to support the aforementioned hypothesis. We observed the turning behavior of finless porpoises in Omura Bay, Japan, using land-based and unmanned aerial system observations. We found a strong tendency in finless porpoises to turn counterclockwise with their right side down when pursuing and catching fish at the surface of the water. Our results suggest that this population of finless porpoises shows consistent right-biased laterality. Right-biased laterality has been observed in various foraging cetaceans and is usually explained by the dominance of the right eye-left cerebral hemisphere in prey recognition; however, right-biased laterality in foraging cetaceans may have multiple causes.


Assuntos
Lateralidade Funcional , Movimento , Toninhas/fisiologia , Animais , Comportamento Animal , Encéfalo/fisiologia
17.
J Acoust Soc Am ; 150(2): 1243, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34470267

RESUMO

Ocean noise has a negative impact on the acoustic recordings of odontocetes' echolocation clicks. In this study, deep convolutional autoencoders (DCAEs) are presented to denoise the echolocation clicks of the finless porpoise (Neophocaena phocaenoides sunameri). A DCAE consists of an encoder network and a decoder network. The encoder network is composed of convolutional layers and fully connected layers, whereas the decoder network consists of fully connected layers and transposed convolutional layers. The training scheme of the denoising autoencoder was applied to learn the DCAE parameters. In addition, transfer learning was employed to address the difficulty in collecting a large number of echolocation clicks that are free of ambient sea noise. Gabor functions were used to generate simulated clicks to pretrain the DCAEs; subsequently, the parameters of the DCAEs were fine-tuned using the echolocation clicks of the finless porpoise. The experimental results showed that a DCAE pretrained with simulated clicks achieved better denoising results than a DCAE trained only with echolocation clicks. Moreover, deep fully convolutional autoencoders, which are special DCAEs that do not contain fully connected layers, generally achieved better performance than the DCAEs that contain fully connected layers.


Assuntos
Ecolocação , Toninhas , Animais , Aprendizagem , Aprendizado de Máquina , Redes Neurais de Computação
18.
J Exp Biol ; 224(16)2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34387665

RESUMO

Echolocating toothed whales face the problem that high sound speeds in water mean that echoes from closely spaced targets will arrive at time delays within their reported auditory integration time of some 264 µs. Here, we test the hypothesis that echolocating harbour porpoises cannot resolve and discriminate targets within a clutter interference zone given by their integration time. To do this, we trained two harbour porpoises (Phocoena phocoena) to actively approach and choose between two spherical targets at four varying inter-target distances (13.5, 27, 56 and 108 cm) in a two-alternative forced-choice task. The free-swimming, blindfolded porpoises were tagged with a sound and movement tag (DTAG4) to record their echoic scene and acoustic outputs. The known ranges between targets and the porpoise, combined with the sound levels received on target-mounted hydrophones revealed how the porpoises controlled their acoustic gaze. When targets were close together, the discrimination task was more difficult because of smaller echo time delays and lower echo level ratios between the targets. Under these conditions, buzzes were longer and started from farther away, source levels were reduced at short ranges, and the porpoises clicked faster, scanned across the targets more, and delayed making their discrimination decision until closer to the target. We conclude that harbour porpoises can resolve and discriminate closely spaced targets, suggesting a clutter rejection zone much shorter than their auditory integration time, and that such clutter rejection is greatly aided by spatial filtering with their directional biosonar beam.


Assuntos
Ecolocação , Phocoena , Toninhas , Acústica , Animais , Som , Natação
19.
Environ Pollut ; 290: 118007, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461413

RESUMO

We investigated the tissue distribution, trophic transfer, and ecological risk of 13 trace elements in 26 East Asian finless porpoises (Neophocaena asiaeorientalis sunameri), an endangered species found in the Liaodong Bay and the north Yellow Sea. All the investigated trace elements were detected in the tissue and food web of the East Asian finless porpoises. The concentrations of the potentially toxic elements were 2.37 × 10-5 - 754 mg kg-1 dry weight (dw) in stranded porpoises and 0.01-159 mg kg-1 dw in their food web. Tissue-specific distribution of the trace elements generally ranked as: liver > kidney > heart > lung > muscle. Zn was the dominant contaminant in the five investigated tissues. Significant positive correlations were found between body length or age and some trace elements, especially Cd. Adults (≥2 years old) presented higher concentrations of most of the trace elements than juveniles (<2 years old). Sex-dependent distribution of the trace elements was insignificant except for Mn, Ni, and Zn in muscle and renal tissue. As, Cu, Mn, Ni, Pb, and V biodiluted across the East Asian finless porpoise food web while Zn biomagnified. However, Hg, Cd, Co, Cr, Se, and Sn did not exhibit apparent trophic transfer trends. Overall, ecological risk assessment of trace elements in East Asian finless porpoises suggested that greater attention should be given to Hg, As, Cd, and Se.


Assuntos
Mercúrio , Toninhas , Oligoelementos , Animais , Músculos , Distribuição Tecidual
20.
Sci Rep ; 11(1): 15485, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326428

RESUMO

A dense bridge-like tissue named the myodural bridge (MDB) connecting the suboccipital muscles to the spinal dura mater was originally discovered in humans. However, recent animal studies have revealed that the MDB appears to be an evolutionarily conserved anatomic structure which may have significant physiological functions. Our previous investigations have confirmed the existence of the MDB in finless porpoises. The present authors conducted research to expound on the specificity of the MDB in the porpoise Neophocana asiaeorientalis (N.asiaeorientalis). Five carcasses of N.asiaeorientalis, with formalin fixation, were used for the present study. Two of the carcasses were used for head and neck CT scanning, three-dimensional reconstructions, and gross dissection of the suboccipital region. Another carcass was used for a P45 plastination study. Also, a carcass was used for a histological analysis of the suboccipital region and also one was used for a Scanning Electron Microscopy study. The results revealed that the MDB of the N.asiaeorientalis is actually an independent muscle originating from the caudal border of the occiput, passing through the posterior atlanto-occipital interspace, and then attaches to the cervical spinal dura mater. Thus the so called MDB of the N.asiaeorientalis is actually an independent and uniquely specialized muscle. Based on the origin and insertion of this muscle, the present authors name it the 'Occipital-Dural Muscle'. It appears that the direct pull of this muscle on the cervical spinal dura mater may affect the circulation of the cerebrospinal fluid by altering the volume of the subarachnoid space via a pumping action.


Assuntos
Articulação Atlantoccipital/fisiologia , Sistema Musculoesquelético , Músculos do Pescoço/diagnóstico por imagem , Músculos do Pescoço/fisiologia , Animais , Vértebras Cervicais/fisiologia , Dura-Máter/fisiologia , Cabeça , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Pescoço , Neurofisiologia , Toninhas , Especificidade da Espécie , Tomografia Computadorizada por Raios X
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