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1.
PLoS One ; 12(7): e0181179, 2017.
Article in English | MEDLINE | ID: mdl-28704486

ABSTRACT

Few accounts describe predator-prey interactions between common bottlenose dolphins (Tursiops truncatus Montagu 1821) and marine catfish (Ariopsis felis Linnaeus 1766, Bagre marinus Mitchill 1815). Over the course of 50,167 sightings of bottlenose dolphin groups in Mississippi Sound and along the Florida coast of the Gulf of Mexico, severed catfish heads were found floating and exhibiting movements at the surface in close proximity to 13 dolphin groups that demonstrated feeding behavior. These observations prompted a multi-disciplinary approach to study the predator-prey relationship between bottlenose dolphins and marine catfish. A review was conducted of bottlenose dolphin visual survey data and dorsal fin photographs from sightings where severed catfish heads were observed. Recovered severed catfish heads were preserved and studied, whole marine catfish were collected and examined, and stranding network pathology reports were reviewed for references to injuries related to fish spines. Photographic identification analysis confirms eight dolphins associated with severed catfish heads were present in three such sightings across an approximately 350 km expanse of coast between the Mississippi Sound and Saint Joseph Bay, FL. An examination of the severed catfish heads indicated interaction with dolphins, and fresh-caught whole hardhead catfish (A. felis) were examined to estimate the presumed total length of the catfish before decapitation. Thirty-eight instances of significant trauma or death in dolphins attributed to ingesting whole marine catfish were documented in stranding records collected from the southeastern United States of America. Bottlenose dolphins typically adhere to a ram-feeding strategy for prey capture followed by whole prey ingestion; however, marine catfish skull morphology may pose a consumption hazard due to rigid spines that can puncture and migrate through soft tissue, prompting a prey handling technique for certain dolphins, facilitating consumption of the posterior portion of the fish without the head.


Subject(s)
Bottle-Nosed Dolphin/physiology , Catfishes/physiology , Predatory Behavior , Animals
2.
Oecologia ; 178(2): 415-25, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25656585

ABSTRACT

We examine individual specialization in foraging habits (foraging habitat and trophic level) of female bottlenose dolphins (Tursiops truncatus) resident in Sarasota Bay, Florida, USA, by analyzing time series of stable isotope (δ(15)N and δ(13)C) values in sequential growth layer groups within teeth. The isotope data provide a chronology of foraging habits over the lifetime of the individual and allowed us to show that female bottlenose dolphins exhibit a high degree of individual specialization in both foraging habitat and trophic level. The foraging habits used by adult females are similar to those they used as calves and may be passed down from mother to calf through social learning. We also characterized the foraging habits and home range of each individual by constructing standard ellipses from isotope values and dolphin sightings data (latitude and longitude), respectively. These data show that Sarasota Bay bottlenose dolphins forage within a subset of the habitats in which they are observed. Moreover, females with similar observational standard ellipses often possessed different foraging specializations. Female bottlenose dolphins may demonstrate individual specialization in foraging habits because it reduces some of the cost of living in groups, such as competition for prey.


Subject(s)
Bottle-Nosed Dolphin/physiology , Ecosystem , Estuaries , Feeding Behavior/physiology , Animals , Female , Florida , Nutritional Status , Social Behavior
3.
Front Endocrinol (Lausanne) ; 4: 139, 2013 Oct 10.
Article in English | MEDLINE | ID: mdl-24133483

ABSTRACT

Free-ranging bottlenose dolphins (Tursiops truncatus) living in Sarasota Bay, Florida appear to have a lower risk of developing insulin resistance and metabolic syndrome compared to a group of dolphins managed under human care. Similar to humans, differences in diet and activity cycles between these groups may explain why Sarasota dolphins have lower insulin, glucose, and lipids. To identify potential protective factors against metabolic syndrome, existing and new data were incorporated to describe feeding and activity patterns of the Sarasota Bay wild dolphin community. Sarasota dolphins eat a wide variety of live fish and spend 10-20% of daylight hours foraging and feeding. Feeding occurs throughout the day, with the dolphins eating small proportions of their total daily intake in brief bouts. The natural pattern of wild dolphins is to feed as necessary and possible at any time of the day or night. Wild dolphins rarely eat dead fish or consume large amounts of prey in concentrated time periods. Wild dolphins are active throughout the day and night; they may engage in bouts of each key activity category at any time during daytime. Dive patterns of radio-tagged dolphins varied only slightly with time of day. Travel rates may be slightly lower at night, suggesting a diurnal rhythm, albeit not one involving complete, extended rest. In comparison, the managed dolphins are older; often fed a smaller variety of frozen-thawed fish types; fed fish species not in their natural diet; feedings and engaged activities are often during the day; and they are fed larger but fewer meals. In summary, potential protective factors against metabolic syndrome in dolphins may include young age, activity, and small meals fed throughout the day and night, and specific fish nutrients. These protective factors against insulin resistance and type 2 diabetes are similar to those reported in humans. Further studies may benefit humans and dolphins.

4.
Biol Lett ; 9(3): 20121036, 2013 Jun 23.
Article in English | MEDLINE | ID: mdl-23637389

ABSTRACT

Diet is a fundamental aspect of animal ecology. Cetacean prey species are generally identified by examining stomach contents of stranded individuals. Critical uncertainty in these studies is whether samples from stranded animals are representative of the diet of free-ranging animals. Over two summers, we collected faecal and gastric samples from healthy free-ranging individuals of an extensively studied bottlenose dolphin population. These samples were analysed by molecular prey detection and these data compared with stomach contents data derived from stranded dolphins from the same population collected over 22 years. There was a remarkable consistency in the prey species composition and relative amounts between the two datasets. The conclusions of past stomach contents studies regarding dolphin habitat associations, prey selection and proposed foraging mechanisms are supported by molecular data from live animals and the combined dataset. This is the first explicit test of the validity of stomach contents analysis for accurate population-scale diet determination of an inshore cetacean.


Subject(s)
Diet , Dolphins , Gastrointestinal Contents , Animals , Predatory Behavior
5.
Parasitol Res ; 108(4): 781-92, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21212982

ABSTRACT

In the present study, 407 anisakid nematodes, collected from 11 different species of cetaceans of the families Delphinidae, Kogiidae, Physeteridae, and Ziphiidae, from the southeastern Atlantic coasts of USA, the Gulf of Mexico, and the Caribbean Sea, were examined morphologically and genetically characterized by PCR restriction fragment length polymorphism to identify them to species level, assess their relative frequencies in definitive hosts, and determine any host preference. Sequence data from nuclear ribosomal internal transcribed spacer and mitochondrial cox2 genes were analysed by maximum parsimony and Bayesian inference methods, as separate and combined datasets, to evaluate phylogenetic relationships among taxa. The results revealed a highly diverse ascaridoid community. Seven Anisakis species and Pseudoterranova species were recovered as adult parasites. Larval forms of Contracaecum multipapillatum were also found in a coastal population of bottlenose dolphins. The phylogenetic trees obtained from the combined dataset (and most individual datasets) revealed the existence of distinct clades, the first including species of the Anisakis simplex complex (A. simplex s.s., Anisakis pegreffii, A. simplex C), (Anisakis nascettii, Anisakis ziphidarum) and the second including Pseudoterranova ceticola ((Anisakis paggiae, (Anisakis physeteris, Anisakis brevispiculata)). This finding, excluding the relationship of P. ceticola, is consistent with the morphology of adult and larval specimens. Considering the presence versus absence of an intestinal cecum, the relationship of P. ceticola with the members of the second clade of Anisakis appears inconsistent with morphological evidences but consistent with host preference. The position of Anisakis typica as the sister group to the two main anisakid clades indicates that it represents a third distinct lineage.


Subject(s)
Ascaridoidea/classification , Ascaridoidea/isolation & purification , Cetacea/parasitology , Phylogeny , Animals , Ascaridoidea/genetics , Caribbean Region , Cluster Analysis , Cyclooxygenase 2/genetics , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Helminth Proteins/genetics , Mexico , Molecular Sequence Data , Molecular Typing , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Sequence Analysis, DNA , Southeastern United States
6.
Syst Parasitol ; 61(3): 157-71, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16025205

ABSTRACT

In the present study, a new biological species of Anisakis Dujardin, 1845, was detected in Kogia breviceps and K. sima from West Atlantic waters (coast of Florida) on the basis of 19 (nuclear) structural genes studied by multilocus allozyme electrophoresis. Fixed allele differences at 11 enzyme loci were found between specimens of both adults and larvae of the new species and the other Anisakis spp. tested. Reproductive isolation from A. brevispiculata Dollfus, 1968 was demonstrated by the lack of hybrid or recombinant genotypes in mixed infections in K. breviceps. Genetic distance of the new species from its closest relative, A. brevispiculata, was D(Nei)=0.79. The new species is morphologically different from the other species which have been genetically characterised and from the other Anisakis retained by Davey (1971) as valid or as species inquirendae: the name of Anisakis paggiae n. sp. is proposed for the new taxon. Anisakis Type II larvae (sensu Berland, 1961) from the European hake Merluccius merluccius in the northeastern Atlantic Ocean (Galician coast) and from the scabbard fish Aphanopus carbo in Central Atlantic waters (off Madeira), were identified as A. paggiae n. sp. Its genetic relationships with respect to the seven species previously characterised (A. simplex (Rudolphi, 1809) sensu stricto), A. pegreffii Campana-Rouget & Biocca, 1955, A. simplex, (A. typica (Diesing, 1860), A. ziphidarum Paggi et al., 1998, A. physeteris Baylis, 1923 and A. brevispiculata) were also inferred. Overall, a low genetic identity was detected at allozyme level between the eight Anisakis species. Interspecific genetic identity ranged from I(Nei)=0.68, between the sibling species of the A. simplex complex, to I(Nei)=0.00 (no alleles shared at the considered loci) when A. physeteris, A. brevispiculata and the new species were compared with the other species of the genus. Concordant topologies were obtained using both UPGMA and NJ tree analyses for the considered species. In both analyses, A. paggiae n. sp. clustered with A. brevispiculata. They also indicated two main clades, the first including A. physeteris, A. brevispiculata and A. paggiae n. sp., the second containing all of the remaining species (i.e. A. simplex (s.s.), A. pegreffii, A. simplex, A. typica and A. ziphidarum). A deep separation between these two main Anisakis clades, also supported by high bootstrap values at the major nodes, was apparent. This is also supported by differences in adult and larval morphology, as well as with respect to their main definitive hosts. A morphological key for distinguishing adult A. paggiae n. sp., A. physeteris and A. brevispiculata is presented. Allozyme markers for the identification of any life-history stage of the Anisakis spp. so far studied, as well as ecological data on their definitive host preferences and geographical distribution, are updated.


Subject(s)
Anisakis/classification , Anisakis/genetics , Cetacea/parasitology , Alleles , Animals , Anisakis/anatomy & histology , Anisakis/enzymology , Electrophoresis , Enzymes/chemistry , Enzymes/genetics , Female , Genetic Variation , Male , Phylogeny
7.
Nature ; 435(7043): 755-6, 2005 Jun 09.
Article in English | MEDLINE | ID: mdl-15944690

ABSTRACT

Potent marine neurotoxins known as brevetoxins are produced by the 'red tide' dinoflagellate Karenia brevis. They kill large numbers of fish and cause illness in humans who ingest toxic filter-feeding shellfish or inhale toxic aerosols. The toxins are also suspected of having been involved in events in which many manatees and dolphins died, but this has usually not been verified owing to limited confirmation of toxin exposure, unexplained intoxication mechanisms and complicating pathologies. Here we show that fish and seagrass can accumulate high concentrations of brevetoxins and that these have acted as toxin vectors during recent deaths of dolphins and manatees, respectively. Our results challenge claims that the deleterious effects of a brevetoxin on fish (ichthyotoxicity) preclude its accumulation in live fish, and they reveal a new vector mechanism for brevetoxin spread through food webs that poses a threat to upper trophic levels.


Subject(s)
Dinoflagellida/chemistry , Food Chain , Mammals/metabolism , Marine Biology , Marine Toxins/analysis , Oxocins/analysis , Animals , Dolphins/metabolism , Fishes/metabolism , Gastrointestinal Contents/chemistry , Humans , Trichechus/metabolism
8.
Radiol. bras ; 36(6): 379-384, nov.-dez. 2003. ilus
Article in Portuguese | LILACS | ID: lil-355958

ABSTRACT

As lesões expansivas do plexo coróide constituem um grupo bastante amplo e heterogêneo de doenças e seus simuladores. Tumores, infecções, anomalias congênitas, hemorragias, cistos e fenômenos degenerativos são alguns dos exemplos de causas de lesões expansivas do plexo coróide. No presente trabalho fizemos revisão da literatura pertinente, descrevendo os achados de imagem e ilustrando-os com alguns casos do nosso serviço. Apesar de não existir na literatura descrição de sinais patognomônicos, a avaliação criteriosa e sistemática das características das lesões pode sugerir determinada etiologia.


Choroid plexus mass lesions encompass a broad and heterogeneous group of diseases and their simulators. Tumors, infections, congenital anomalies, hemorrhage, cysts and degenerative diseases are some examples of mass lesions affecting the choroid plexus. In this article we review the current literature, describing the imaging findings and illustrating choroid plexus mass lesions with some cases diagnosed at our facility. Despite the inexistence of pathognomonic signs, a careful and systematic evaluation of the imaging characteristics may suggest many etiologies.


Subject(s)
Humans , Brain Diseases , Choroid Plexus Neoplasms , Choroid Plexus/physiopathology , Choroid Plexus/injuries , Diagnosis, Differential , Lung Diseases/diagnosis , Tomography, X-Ray Computed
9.
Arq. neuropsiquiatr ; 56(1): 45-52, mar. 1998. tab
Article in Portuguese | LILACS | ID: lil-212441

ABSTRACT

Objetivo: Investigar a ocorrência e os fatores de risco para morbidade depressiva em uma amostra de 38 pacientes ambulatoriais com neurosisticercose. Métodos: O diagnóstico psiquiátrico baseou-se nos exames do estado mental atual e pregresso, respectivamente obtidos pelas entrevistas estruturadas do PSE-9 e SADS-L; as funçoes cognitivas foram avaliadas pelo MMS e pelo roteiro de Strub & Black (Mental Status Examination). Resultados: Transtornos depressivos foram o achado psiquiátrico mais frequente (63,1 por cento) entre os pacientes da amostra. Destes, 20 (52,6 por cento) mostravam-se deprimidos no momento da avaliaçao e 4 apresentaram depressao no passado. Entre os pacientes deprimidos, 16 preencheram critérios diagnósticos do DSM-III-R para transtorno orgânico do humor (k = 0,4). Antecedentes pessoais de depressao (p = 0,006), sinais de atividade da doença (p = 0,044) e ocorrência de hipertensao intracraniana (p=0,065) foram os parâmetros clínicos que se correlacionaram com a presença de depressao. Conclusoes: Tais achados, aliados à ausência de predomínio do sexo feminino entre os casos de depressao, sugerem etiologia orgânica. Os autores discutem essas observaçoes à luz da literatura sobre outros transtornos mentais orgânicos.


Subject(s)
Adult , Middle Aged , Female , Humans , Brain Diseases/parasitology , Cysticercosis/complications , Depressive Disorder/etiology , Brain Diseases/complications , Cysticercosis/psychology , Depressive Disorder , Depressive Disorder/diagnosis , Depressive Disorder/parasitology , Morbidity , Prevalence , Risk Factors
10.
Arq. neuropsiquiatr ; 54(3): 375-83, set. 1996. ilus, tab
Article in English | LILACS | ID: lil-184765

ABSTRACT

The aim of this study was to compare the accuracy of computed tomography (CT) and single photon emission computerized tomography (SPECT) in the diagnosis of dementia. Fifty-two patients with clinical diagnosis of dementia and 11 controls were studied. The scans were interpreted by one experienced neuroradiologist and one nuclear radiologist, both blinded to the clinical data. In the diagnosis of dementia, CT and SPECT showed equal sensitivity (82.7 per cent) and statistically similar specificity (63.8 and 81.8 per cent, respectively). The specificity of SPECT in diagnosing Alzheimer's disease (100 per cent) was statistically superior to CT (69 per cent). However, both methods showed similar sensitivity in detecting Alzheimer's disease. In conclusion, SPECT and CT showed similar accuracy in the diagnosis of dementia. The quite high specificity of SPECT in Alzheimer's disease may be useful for confirming that diagnosis, particularly for patients with presenile onset of the disease.


Subject(s)
Humans , Adult , Middle Aged , Dementia/diagnosis , Tomography, Emission-Computed , Tomography, X-Ray Computed , Aged, 80 and over , Dementia, Vascular/diagnosis , Dementia , Dementia , Diagnosis, Differential , Alzheimer Disease/diagnosis , Follow-Up Studies , Prospective Studies , Sensitivity and Specificity
11.
In. Machado, Luís dos ramos; Livramento, José Antonio; Netto, Antonio Spina-França; Nóbrega, José Paulo Smith. Neuroinfecçäo 96. Säo Paulo, Clínica Neurológica HC/FMUSP, 1996. p.51-54, tab.
Monography in Portuguese | LILACS | ID: lil-179839
12.
In. Machado, Luis dos Ramos; Nóbrega, José Paulo Smith; Livramento, José Antonio; Spina França Netto, Antonio. Neuroinfecçäo 94. Säo Paulo, Hospital das Clínicas da Faculdade de Medicina da Universidade de Säo Paulo. Clínica Neurológica, 1994. p.117-118.
Monography in Portuguese | LILACS | ID: lil-154967
14.
Arq. bras. neurocir ; 7(1): 39-45, mar. 1988. ilus, tab
Article in Portuguese | LILACS | ID: lil-68431

ABSTRACT

Os autores descrevem a ténica de estereotomografia utilizada para biópsia estereotomográfica (14 doentes) e para a localizaçäo de malformaçäo arteriovenosa profunda, a fim de permitir o correto acesso cirúrgico (1 doente). Concluem pela simplicidade, maleabilidade, precisäo e segurança do método, em comparaçäo com a biópsia estereotáxica convencional


Subject(s)
Child , Adolescent , Adult , Middle Aged , Humans , Cerebrovascular Disorders/pathology , Biopsy , Stereotaxic Techniques , Tomography, X-Ray Computed
15.
Rev. paul. pediatr ; 4(15): 144-6, dez. 1986. ilus
Article in Portuguese | LILACS | ID: lil-43094

ABSTRACT

O artigo apresenta o caso de um RN que apresentou uma encefalopatia hipóxico-isquêmica neonatal grave e evoluiu para uma leucoencefalopatia multicística, documentada pelos exames ultra-sonográficos evolutivos. A reabsorçäo do parênquima cerebral foi täo extensa que o aspecto tomográfico com 3 meses de idade lembrava um caso de hidranencefalia. A criança evoluiu com crises convulsivas que foram controladas com medicaçäo anticonvulsivante e coma que regrediu lentamente. Por ocasiäo da alta hospitalar apresentava um exame neurológico francamente anormal, com tetraplegia espástica e contacto pobre com o meio


Subject(s)
Infant, Newborn , Humans , Female , Encephalomalacia/diagnosis , Tomography, X-Ray Computed , Ultrasonography
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