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1.
Sci Rep ; 8(1): 11577, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068967

RESUMO

Mass strandings of sperm whales (Physeter macrocephalus) are rare in the Mediterranean Sea. Nevertheless, in 2014 a pod of 7 specimens stranded alive along the Italian coast of the Central Adriatic Sea: 3 individuals died on the beach after a few hours due to internal damages induced by prolonged recumbency; the remaining 4 whales were refloated after great efforts. All the dead animals were genetically related females; one was pregnant. All the animals were infected by dolphin morbillivirus (DMV) and the pregnant whale was also affected by a severe nephropathy due to a large kidney stone. Other analyses ruled out other possible relevant factors related to weather conditions or human activities. The results of multidisciplinary post-mortem analyses revealed that the 7 sperm whales entered the Adriatic Sea encountering adverse weather conditions and then kept heading northward following the pregnant but sick leader of the pod, thereby reaching the stranding site. DMV infection most likely played a crucial role in impairing the health condition and orientation abilities of the whales. They did not steer back towards deeper waters, but eventually stranded along the Central Adriatic Sea coastline, a real trap for sperm whales.


Assuntos
Comportamento Animal , Infecções por Morbillivirus/veterinária , Morbillivirus/isolamento & purificação , Cachalote , Animais , Itália , Mar Mediterrâneo , Infecções por Morbillivirus/patologia
3.
Anat Rec (Hoboken) ; 298(7): 1294-300, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25676796

RESUMO

The present study, performed with a dual-energy X-ray (DXA) bone densitometer on a series of fetal and newborn striped and short-beaked common dolphins, shows that the bone density of the area of the tympanic bulla within the tympanoperiotic complex starts with 0.483 g cm(-2) in 5- to 6-month-old specimens of striped (or common) dolphin fetuses and reaches 1.841 g cm(-2) in newborn striped dolphins, with values consistently higher than in other parts of the skull or elsewhere in the skeleton. The same results apply to the common bottlenose dolphins, in which the area of the tympanic bulla has a density of 0.312 g cm(-2) in 5-month-old specimens and becomes four times as much in newborns. Regardless of the areal bone density results correlated to the DXA-technique, comparisons with DXA-bone density data in the literature referred to other mammals emphasize the presence of very high mineral deposition in the area of the tympanoperiotic bone in fetal and newborn dolphins and the most dense part of it belongs to the tympanic bulla. The early osseous maturation of the tympanic bulla area may be compared to what described in fin whales and may represent an unique ontogenetic and phylogenetic feature of cetaceans, possibly related to the development of essential acoustic sense and establishment of immediate post-natal mother-calf relationship.


Assuntos
Adaptação Fisiológica/fisiologia , Golfinhos/fisiologia , Osteogênese/fisiologia , Osso Temporal/fisiologia , Animais , Animais Recém-Nascidos , Evolução Biológica , Ecossistema
4.
Mar Environ Res ; 100: 94-111, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25016937

RESUMO

The Marine Strategy Framework Directive (MSFD) requires the assessment of the environmental status in relation to human pressures. In this study the biodiversity of the cetacean community is proposed as MSFD descriptor of the environmental status and its link with anthropogenic pressures is investigated. Functional groups are generally favoured over indicator species since they are thought to better reflect to anthropogenic stressors. Cetaceans are in many situations the most well known component of pelagic ecosystems. Their habitat requirements are known and can be used to evaluate the theoretical biodiversity that should be expected in a certain area. The deviations between the theoretical biodiversity and the actual biodiversity may be used to detect the impacts of human activities. Based on this analysis fishery resulted to be by far the most significant of the existing pressures. Among all the species, bottlenose dolphin was found the most correlated with the fishery sector dynamics.


Assuntos
Biodiversidade , Cetáceos/fisiologia , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Animais , União Europeia , Pesqueiros
5.
Dis Aquat Organ ; 109(1): 81-6, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24781797

RESUMO

An unusual mortality event involving cetaceans, mainly striped dolphins Stenella coeruleoalba (Meyen, 1833), occurred along the Tyrrhenian Sea coast of Italy during the first 3 mo of 2013. Based on post-mortem analyses carried out according to body condition on 66 dolphins (54% of stranded animals), several hypotheses to explain the causes of this mortality event were proposed. Although no definitive conclusions can be drawn, dolphin morbillivirus was deemed the most likely cause, although other infectious agents (including Photobacterium damselae damselae and herpesvirus) or environmental factors may also have contributed to this recent mortality event.


Assuntos
Cetáceos/virologia , Animais , Itália , Mar Mediterrâneo , Morbillivirus/classificação , Morbillivirus/isolamento & purificação , Infecções por Morbillivirus/epidemiologia , Infecções por Morbillivirus/mortalidade , Infecções por Morbillivirus/veterinária , Fatores de Tempo
6.
PLoS One ; 7(5): e37110, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22615912

RESUMO

The evolution of the cetacean skeleton followed a path that differentiated this group from other terrestrial mammals about 50 million years ago [1], and debate is still going on about the relationships between Cetacea and Artiodactyla [2], [3], [4]. Some skeletal traits of the basilosaurids (the more advanced forms of Archaeocetes), such as the expansion of the peribullary air sinuses, dental modification and vertebral size uniformity [5] are maintained and further emphasized also in contemporary odontocetes and mysticetes. Using Dual-Energy X-Ray Absorptiometry here we report that the deposition of bone mineral in fetal and newborn specimens of the fin whale Balaenoptera physalus is remarkably higher in the bulla tympanica than in the adjacent basal skull or in the rest of the skeleton. Ossification of the tympanic bulla in fetal Artiodactyla (bovine, hippopotamus) is minimal, becomes sensible after birth and then progresses during growth, contrarily to the precocious mineralization that we observed in fin whales. Given the importance of the ear bones for the precise identification of phylogenetic relationship in therian evolution [6], this feature may indicate a specific evolutionary trait of fin whales and possibly other cetacean species or families. Early mineralization of the tympanic bulla allows immediate sound conduction in the aquatic medium and consequently holds potential importance for mother-calf relationship and postnatal survival.


Assuntos
Calcificação Fisiológica/fisiologia , Baleia Comum/metabolismo , Osso Temporal/metabolismo , Absorciometria de Fóton/métodos , Animais , Animais Recém-Nascidos , Evolução Biológica , Feto , Osteogênese/fisiologia , Filogenia
7.
PLoS One ; 6(5): e19417, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21673789

RESUMO

BACKGROUND: Mass strandings of sperm whales (Physeter macrocephalus) remain peculiar and rather unexplained events, which rarely occur in the Mediterranean Sea. Solar cycles and related changes in the geomagnetic field, variations in water temperature and weather conditions, coast geographical features and human activities have been proposed as possible causes. In December 2009, a pod of seven male sperm whales stranded along the Adriatic coast of Southern Italy. This is the sixth instance from 1555 in this basin. METHODOLOGY/PRINCIPAL FINDINGS: Complete necropsies were performed on three whales whose bodies were in good condition, carrying out on sampled tissues histopathology, virology, bacteriology, parasitology, and screening of veins looking for gas emboli. Furthermore, samples for age determination, genetic studies, gastric content evaluation, stable isotopes and toxicology were taken from all the seven specimens. The animals were part of the same group and determined by genetic and photo-identification to be part of the Mediterranean population. Causes of death did not include biological agents, or the "gas and fat embolic syndrome", associated with direct sonar exposure. Environmental pollutant tissue concentrations were relatively high, in particular organochlorinated xenobiotics. Gastric content and morphologic tissue examinations showed a prolonged starvation, which likely caused, at its turn, the mobilization of lipophilic contaminants from the adipose tissue. Chemical compounds subsequently entered the blood circulation and may have impaired immune and nervous functions. CONCLUSIONS/SIGNIFICANCE: A multi-factorial cause underlying this sperm whales' mass stranding is proposed herein based upon the results of postmortem investigations as well as of the detailed analyses of the geographical and historical background. The seven sperm whales took the same "wrong way" into the Adriatic Sea, a potentially dangerous trap for Mediterranean sperm whales. Seismic surveys should be also regarded as potential co-factors, even if no evidence of direct impact has been detected.


Assuntos
Comportamento Animal/fisiologia , Orientação/fisiologia , Cachalote/fisiologia , Tecido Adiposo/química , Tecido Adiposo/metabolismo , Animais , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Geografia , Humanos , Itália , Masculino , Mar Mediterrâneo , Metais Pesados/química , Metais Pesados/metabolismo , Conceitos Meteorológicos , Cachalote/anatomia & histologia
8.
Anat Rec (Hoboken) ; 293(2): 235-42, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20027645

RESUMO

Toothed whales have undergone a profound telescopic rearrangement of the skull, with elongation of facial bones and formation of a hollow rostrum, filled in vivo by the mesorostral cartilage. In most species of the family Ziphiidae, this latter cartilage becomes secondarily ossified, producing in some cases the densest bone existing in nature. Starting from this observation, we wanted to investigate the patterns of distribution of bone mineral density (BMD) in the rostrum of two families of toothed whales with different ecological and behavioral traits: Delphinidae and Ziphiidae. We analyzed BMD non invasively by means of the dual energy X-ray absorptiometry technology, and found two different density distribution patterns that distinctly set the two families apart. Namely, BMD values decrease from the proximal to the distal region of the rostrum in delphinids, whereas the beaked whales show a BMD peak in the central region. Possible functions such as ballast or protection against clashes might be likely, although more data about the species of both families is needed to give better evidence.


Assuntos
Densidade Óssea , Cartilagem/anatomia & histologia , Golfinhos/anatomia & histologia , Ossos Faciais/anatomia & histologia , Baleias/anatomia & histologia , Absorciometria de Fóton/estatística & dados numéricos , Animais , Evolução Biológica , Densidade Óssea/genética , Cartilagem/diagnóstico por imagem , Interpretação Estatística de Dados , Golfinhos/genética , Ossos Faciais/diagnóstico por imagem , Padrões de Herança , Especificidade da Espécie , Baleias/genética
9.
J Anat ; 211(5): 639-46, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17850286

RESUMO

The determination of age is an important step in defining the life history traits of individuals and populations. Age determination of odontocetes is mainly based on counting annual growth layer groups in the teeth. However, this useful method is always invasive, requiring the cutting of at least one tooth, and sometimes the results are difficult to interpret. Based on the concept that bone matrix is constantly deposited throughout life, we analysed the bone mineral density of the arm and forearm of a series of bottlenose dolphins (Tursiops truncatus, Montagu 1821) stranded along the Italian coast of the Adriatic Sea or maintained in confined waters. The bone mineral density values we obtained were evaluated as possible age predictors of the Mediterranean population of this species, considering age as determined by counting growth layer groups in sections of the teeth and the total body length of the animal as references. Comparisons between left and right flipper showed no difference. Our results show that bone mineral density values of the thoracic limb are indeed reliable age predictors in Tursiops truncatus. Further investigations in additional odontocete species are necessary to provide strong evidence of the reliability of bone mineral density as an indicator of growth and chronological wear and tear in toothed-whales.


Assuntos
Determinação da Idade pelo Esqueleto/veterinária , Densidade Óssea , Ossos da Extremidade Superior/fisiologia , Golfinho Nariz-de-Garrafa/fisiologia , Absorciometria de Fóton , Animais , Biometria , Ossos da Extremidade Superior/anatomia & histologia , Feminino , Masculino
10.
Anat Rec ; 267(3): 225-30, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12115272

RESUMO

The age of odontocetes living in the wild is determined mainly by analysis of dentine layers in sections of the teeth. We examined a series of specimens from striped dolphins (Stenella coeruleoalba, Meyen, 1833) that had stranded along the Italian coast of the Mediterranean sea. The present study analyzes and describes bone density in the arm and forearm of the stranded specimens, and correlates the data with total body length of the animal and age as determined by the number of dentine layers in sections of the teeth. According to our model, age can be predicted on the basis of bone density and total body length of the stranded animal. This is the first study to use bone density as a biological parameter to understand the wear and tear of life in the sea. The results suggest that bone density is a new tool for recording age in wild odontocetes.


Assuntos
Determinação da Idade pelo Esqueleto/veterinária , Densidade Óssea , Golfinhos , Membro Anterior/crescimento & desenvolvimento , Absorciometria de Fóton , Determinação da Idade pelo Esqueleto/métodos , Distribuição por Idade , Animais , Feminino , Membro Anterior/metabolismo , Masculino , Mar Mediterrâneo
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