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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Ontogenia craniana comparada de Arctocephalus australis, Callorhinus ursinus e Otaria byronia (Otariidae: Pinnipedia)

Sanfelice, Daniela January 2003 (has links)
The search for mechanisms that can generate major morphological changes has led to the study of ontogeny, in part because some kinds of modifications of ontogenies seem an excelent way to generate major phenotypic change. We focus here on Arctocephlaus australis, Callorhinus ursinus and Otaria byronia with the aim of contributing to the understanding of the origin, structure and temporal patterns of otarid morphological diversity. The pattern of change in shape during postnatal development in otarid skull was studied and described by geometric and traditional morphometrics. Our aims are: to compare the skull ontogeny of the species invocated in identifying and in describing shape alterations in the skull; to evaluate and to describe comparatively the sexual dimorphism and disparity during the ontogeny; to study the covariance between size and shape in relationship with age-groups; to investigate the changes in the ontogeny and their relationships with the evolution of the Otariidae Family; to analyze the conservation of ontogenetic trajectories over time, between sexes and among species; to characterize growth trajectories and to compare them among taxa with respect to isometry; to describe the parameters of growth and development of the focused species and to compare the two different approaches employed. Using traditional morphometrics, the allometry vectors for all species were significantly different from isometry. Dimorphism in the allometric vector is observed only in O. byonia and the difference between males and females of the fur seals are related with adult body size. The comparisons species/sex groups revealed similar vectors (any significant shape disassociation are verified in the inter-specific analyzes), suggesting lower plasticity of the ontogenies. Using geometrical methods, the dimorphism is more conspicuous in adult shapes but this is not true for the level of disparity between sexes of O. byronia. Although that dimorphism is linked with size this is not only a question of scaling or allometry (which is present in the morphogenesis of all species, especially in O. byronia). Additionally, the slopes of changes in shape related with size increase are different in A. australis and O. byronia, but are equal in C. ursinus, which is the smaller species. We suggest post-displacement as one of the factors that could have acted in the origin of the sexual dimorphism in the skull of C. ursinus. Heterochrony, perhaps is present in the roots of the modifications suffered by the ontogeny of A. australis and O. byronia too, considering the differences in the rates of development between the sexes of both species (and overall in O. byronia), but surely repatterning allometric is involved too in these cases. We verified that ontogenies can not be summarized by a single linear vector in any analyzed group, where C. ursinus ontogeny is the more linear and O. byronia the more multi-dimensional species among the 3 that we had examined. Shape changes in the otarids studied here are more related with size than with age and any of the species share a common growth allometry or a common ontogenetic trajectory/pattern. In the same way, shapes at onset or offset are not the same in any case. When the three species are pooled together, initial shapes are always very different among the species and the distances between shapes increase with time almost independently from size. On the other hand, when the complete samples are considered, all the ontogenetic trajectories are significantly different in the directions of the allometric vectors during ontogeny. Ontogenetic trajectories differ significantly among almost all the pairs compared, except for the trajectories of A. australis and C. ursinus males. They are no more different than expected by chance considering the range of angles within each sample. A similar pattern is found when the subadults are compared between pairs of species and when we compare adult males of A. australis with adult males of O. byronia. The juveniles are no more different than expected by chance (correlation between ontogenies in that phase is equal to one), excepti between C. ursinus and O. byronia. The ontogenetic trajectory of C. ursinus is the shorter and of O. byronia is the longer being almost three times longer than the former. A. australis has an intermediary length of ontogenetic trajectory. For the sample comprising all three species disparity increase significantly over ontogeny since the disparity of the adults is near the two times of the disparity between juveniles. For any ontogenetic stage, O. byronia is the species that contributes for the disparity of the all group, followed by C. ursinus. When we consider the three species together, the pattern of disparity do not change a lot during ontogeny. Ontogenies examined herein are clearly not constrained and perhaps the differences in patterns have additive effects in the differentiation of the ontogenies. Whether ontogenetic trajectories are linear or curve could be a function of developmental timing or more specifically it could depend on the age at which allometries stabilize in post-natal ontogenies. Otherwise, the amount of differences between species in the ontogenies is in agreement with the phylogenetic relationships. Finally, we addressed basically the following questions: Is onset time the same in the species? Is offset time the same in these species? Does growth rate differ between the species. The answer to those questions could be summarized by the conclusion. but we conclude that the changes in otarids skull ontogenies had occurred in spatial and temporal terms.
2

Ontogenia craniana comparada de Arctocephalus australis, Callorhinus ursinus e Otaria byronia (Otariidae: Pinnipedia)

Sanfelice, Daniela January 2003 (has links)
The search for mechanisms that can generate major morphological changes has led to the study of ontogeny, in part because some kinds of modifications of ontogenies seem an excelent way to generate major phenotypic change. We focus here on Arctocephlaus australis, Callorhinus ursinus and Otaria byronia with the aim of contributing to the understanding of the origin, structure and temporal patterns of otarid morphological diversity. The pattern of change in shape during postnatal development in otarid skull was studied and described by geometric and traditional morphometrics. Our aims are: to compare the skull ontogeny of the species invocated in identifying and in describing shape alterations in the skull; to evaluate and to describe comparatively the sexual dimorphism and disparity during the ontogeny; to study the covariance between size and shape in relationship with age-groups; to investigate the changes in the ontogeny and their relationships with the evolution of the Otariidae Family; to analyze the conservation of ontogenetic trajectories over time, between sexes and among species; to characterize growth trajectories and to compare them among taxa with respect to isometry; to describe the parameters of growth and development of the focused species and to compare the two different approaches employed. Using traditional morphometrics, the allometry vectors for all species were significantly different from isometry. Dimorphism in the allometric vector is observed only in O. byonia and the difference between males and females of the fur seals are related with adult body size. The comparisons species/sex groups revealed similar vectors (any significant shape disassociation are verified in the inter-specific analyzes), suggesting lower plasticity of the ontogenies. Using geometrical methods, the dimorphism is more conspicuous in adult shapes but this is not true for the level of disparity between sexes of O. byronia. Although that dimorphism is linked with size this is not only a question of scaling or allometry (which is present in the morphogenesis of all species, especially in O. byronia). Additionally, the slopes of changes in shape related with size increase are different in A. australis and O. byronia, but are equal in C. ursinus, which is the smaller species. We suggest post-displacement as one of the factors that could have acted in the origin of the sexual dimorphism in the skull of C. ursinus. Heterochrony, perhaps is present in the roots of the modifications suffered by the ontogeny of A. australis and O. byronia too, considering the differences in the rates of development between the sexes of both species (and overall in O. byronia), but surely repatterning allometric is involved too in these cases. We verified that ontogenies can not be summarized by a single linear vector in any analyzed group, where C. ursinus ontogeny is the more linear and O. byronia the more multi-dimensional species among the 3 that we had examined. Shape changes in the otarids studied here are more related with size than with age and any of the species share a common growth allometry or a common ontogenetic trajectory/pattern. In the same way, shapes at onset or offset are not the same in any case. When the three species are pooled together, initial shapes are always very different among the species and the distances between shapes increase with time almost independently from size. On the other hand, when the complete samples are considered, all the ontogenetic trajectories are significantly different in the directions of the allometric vectors during ontogeny. Ontogenetic trajectories differ significantly among almost all the pairs compared, except for the trajectories of A. australis and C. ursinus males. They are no more different than expected by chance considering the range of angles within each sample. A similar pattern is found when the subadults are compared between pairs of species and when we compare adult males of A. australis with adult males of O. byronia. The juveniles are no more different than expected by chance (correlation between ontogenies in that phase is equal to one), excepti between C. ursinus and O. byronia. The ontogenetic trajectory of C. ursinus is the shorter and of O. byronia is the longer being almost three times longer than the former. A. australis has an intermediary length of ontogenetic trajectory. For the sample comprising all three species disparity increase significantly over ontogeny since the disparity of the adults is near the two times of the disparity between juveniles. For any ontogenetic stage, O. byronia is the species that contributes for the disparity of the all group, followed by C. ursinus. When we consider the three species together, the pattern of disparity do not change a lot during ontogeny. Ontogenies examined herein are clearly not constrained and perhaps the differences in patterns have additive effects in the differentiation of the ontogenies. Whether ontogenetic trajectories are linear or curve could be a function of developmental timing or more specifically it could depend on the age at which allometries stabilize in post-natal ontogenies. Otherwise, the amount of differences between species in the ontogenies is in agreement with the phylogenetic relationships. Finally, we addressed basically the following questions: Is onset time the same in the species? Is offset time the same in these species? Does growth rate differ between the species. The answer to those questions could be summarized by the conclusion. but we conclude that the changes in otarids skull ontogenies had occurred in spatial and temporal terms.
3

Ontogenia craniana comparada de Arctocephalus australis, Callorhinus ursinus e Otaria byronia (Otariidae: Pinnipedia)

Sanfelice, Daniela January 2003 (has links)
The search for mechanisms that can generate major morphological changes has led to the study of ontogeny, in part because some kinds of modifications of ontogenies seem an excelent way to generate major phenotypic change. We focus here on Arctocephlaus australis, Callorhinus ursinus and Otaria byronia with the aim of contributing to the understanding of the origin, structure and temporal patterns of otarid morphological diversity. The pattern of change in shape during postnatal development in otarid skull was studied and described by geometric and traditional morphometrics. Our aims are: to compare the skull ontogeny of the species invocated in identifying and in describing shape alterations in the skull; to evaluate and to describe comparatively the sexual dimorphism and disparity during the ontogeny; to study the covariance between size and shape in relationship with age-groups; to investigate the changes in the ontogeny and their relationships with the evolution of the Otariidae Family; to analyze the conservation of ontogenetic trajectories over time, between sexes and among species; to characterize growth trajectories and to compare them among taxa with respect to isometry; to describe the parameters of growth and development of the focused species and to compare the two different approaches employed. Using traditional morphometrics, the allometry vectors for all species were significantly different from isometry. Dimorphism in the allometric vector is observed only in O. byonia and the difference between males and females of the fur seals are related with adult body size. The comparisons species/sex groups revealed similar vectors (any significant shape disassociation are verified in the inter-specific analyzes), suggesting lower plasticity of the ontogenies. Using geometrical methods, the dimorphism is more conspicuous in adult shapes but this is not true for the level of disparity between sexes of O. byronia. Although that dimorphism is linked with size this is not only a question of scaling or allometry (which is present in the morphogenesis of all species, especially in O. byronia). Additionally, the slopes of changes in shape related with size increase are different in A. australis and O. byronia, but are equal in C. ursinus, which is the smaller species. We suggest post-displacement as one of the factors that could have acted in the origin of the sexual dimorphism in the skull of C. ursinus. Heterochrony, perhaps is present in the roots of the modifications suffered by the ontogeny of A. australis and O. byronia too, considering the differences in the rates of development between the sexes of both species (and overall in O. byronia), but surely repatterning allometric is involved too in these cases. We verified that ontogenies can not be summarized by a single linear vector in any analyzed group, where C. ursinus ontogeny is the more linear and O. byronia the more multi-dimensional species among the 3 that we had examined. Shape changes in the otarids studied here are more related with size than with age and any of the species share a common growth allometry or a common ontogenetic trajectory/pattern. In the same way, shapes at onset or offset are not the same in any case. When the three species are pooled together, initial shapes are always very different among the species and the distances between shapes increase with time almost independently from size. On the other hand, when the complete samples are considered, all the ontogenetic trajectories are significantly different in the directions of the allometric vectors during ontogeny. Ontogenetic trajectories differ significantly among almost all the pairs compared, except for the trajectories of A. australis and C. ursinus males. They are no more different than expected by chance considering the range of angles within each sample. A similar pattern is found when the subadults are compared between pairs of species and when we compare adult males of A. australis with adult males of O. byronia. The juveniles are no more different than expected by chance (correlation between ontogenies in that phase is equal to one), excepti between C. ursinus and O. byronia. The ontogenetic trajectory of C. ursinus is the shorter and of O. byronia is the longer being almost three times longer than the former. A. australis has an intermediary length of ontogenetic trajectory. For the sample comprising all three species disparity increase significantly over ontogeny since the disparity of the adults is near the two times of the disparity between juveniles. For any ontogenetic stage, O. byronia is the species that contributes for the disparity of the all group, followed by C. ursinus. When we consider the three species together, the pattern of disparity do not change a lot during ontogeny. Ontogenies examined herein are clearly not constrained and perhaps the differences in patterns have additive effects in the differentiation of the ontogenies. Whether ontogenetic trajectories are linear or curve could be a function of developmental timing or more specifically it could depend on the age at which allometries stabilize in post-natal ontogenies. Otherwise, the amount of differences between species in the ontogenies is in agreement with the phylogenetic relationships. Finally, we addressed basically the following questions: Is onset time the same in the species? Is offset time the same in these species? Does growth rate differ between the species. The answer to those questions could be summarized by the conclusion. but we conclude that the changes in otarids skull ontogenies had occurred in spatial and temporal terms.
4

Alterações anatomopatológicas em lobos-marinhos (Otariidae) encontrados na costa do Brasil / Anatomopathological changes in fur seals found ashore on the coast of Brazil

Reisfeld, Laura Chrispim 04 February 2016 (has links)
Diversas doenças emergentes, lesões e agentes infecciosos em mamíferos marinhos foram identificados pela primeira vez em animais encalhados. No Brasil, é comum a ocorrência de encalhes de lobos marinhos que se encontram debilitados e/ou enfermos. Devido à falta de estudos recentes que descrevam as principais causas de morte e alterações histopatológicas nos animais encalhados, o presente trabalho visa contribuir para a patologia comparada e, indiretamente, para a conservação de pinípedes por meio da investigação das principais lesões, enfermidades e causas de morte que acometem estas espécies no sul do Brasil. Para esse estudo, foram analisadas amostras de tecidos de 50 indivíduos de duas espécies de lobos marinhos: lobo-marinho-sul-americano (Arctocephalus australis) e lobo-marinho-subantártico (Artocephalus tropicalis), que foram encontrados ao longo da costa brasileira, incluindo cadáveres e animais recebidos vivos e que vieram a óbito em centros de reabilitação no Brasil. Essas amostras estão armazenadas no Banco de Tecido de Mamíferos Marinhos e foram avaliadas, identificadas e processadas no Laboratório de Histologia do VPT/FMVZ. Os achados histopatológicos que tiveram ocorrência superior ou igual a 30% foram: pneumonia (90%; 44/49), hiperplasia linfoide em linfonodo (59%; 19/32), congestão hepática (55%; 27/49), hiperplasia linfoide esplênica (55%; 24/44), edema pulmonar (53%; 26/49), enterite em intestino delgado (51%; 18/35), traqueíte (45%; 14/31), hepatite (43%; 21/49), enterite em intestino grosso (42%; 13/31), congestão pulmonar (33%; 16/49), expansão folicular em linfonodo (31%; 10/32) e glomerulonefrite membranosa (30%; 14/47). Dois casos de interesse especial foram reportados; um indíviduo de A. australis com possível causa de morte associada a meningoencefalite causada por protozoário da família Sarcocystidae e um indíviduo de A. tropicalis em que foi observado linfoma. Em uma análise geral, o principal sistema acometido foi o respiratório com 34% (17/50) dos casos, seguido por processos infecciosos, registrados em 28% (14/50) dos casos, sendo que infecções parasitárias por parafilaroides representaram 30,7% (4/13) das causas de morte de A. tropicalis. Dentre os infecciosos, a septicemia representou 42% (6/14) dos casos e foi reportada com maior frequência em A. australis. As outras causas de morte também observadas foram: nutricional (caquexia) 10% (5/50), indeterminada 10% (5/50), digestivo (enterite e hepatite) 6%(3/50), circulatório (choque) 6% (3/50), metabólico (estresse) 4% (2/50) e neoplasia (linfoma), observada em um único caso. Acreditamos que a análise dos dados obtidos no presente trabalho poderá fornecer um panorama sobre as doenças que indivíduos dessas espécies em vida livre possam apresentar em situações de encalhe e durante a reabilitação. Quantificar e entender as causas de encalhe de pinípedes irá fornecer importantes dados aos centros de reabilitação, que por sua vez, poderão utilizar essas informações para planejar cuidados veterinários adequados / Many emerging diseases, injuries and infectious agents in marine mammals have been identified for the first time in stranded animals. Stranding of fur seals that are weak and/or debilitated is common in Brazil. Due to lack of recent studies describing the main causes of death and histopathological changes in stranded animals, this paper aims to contribute to the comparative pathology and indirectly, for the conservation of pinnipeds, by investigating major injuries, illnesses and causes of death that affect these animals in southern Brazil. For this study, we analyzed tissue samples from 50 individuals from two species of sea lions: South American fur seal (Arctocephalus australis) and Sub-Antarctic fur seal (Artocephalus tropicalis), which were found along the Brazilian coast, including carcasses and animals that died in rehabilitation centers in Brazil. These samples are stored in the Marine Mammal Tissue Bank and were evaluated, identified and processed in the Laboratory of Histology (VPT/FMVZ). Histopathological findings that had occurrence equal to 30 % or higher were: pneumonia (90%; 44/49), lymphoid hyperplasia in lymph node (59%; 19/32), hepatic congestion (55%; 27/49), splenic lymphoid hyperplasia (55%; 24/44), pulmonary edema (53%; 26/49), small intestine enteritis (51%; 18/35), tracheitis (45%; 14/31), hepatitis (43%; 21/4 9), large intestine enteritis (42%; 13/31), pulmonary congestion (33%; 16/49), follicular expansion in lymph node (31%; 10/32) and membranous glomerulonephritis (30%; 14/47). Two cases of special interest were reported; one individual of A. australis, with cause of death possibly associated with meningoencephalitis caused by protozoa of Sarcocystidae family, and one individual of A. tropicalis, where lymphoma was observed. In an overview, the main affected system was respiratory with 34% (17/50) of the cases, followed by infectious processes, recorded in 28% (14/50) of the cases, in which Parafilaroides parasitic infections accounted for 30.7% (4/13) of the causes of death for A. tropicalis. Among the infectious process, septicemia accounted for 42% (6/14) of the cases and was more frequently reported in A. australis. Other causes of death that were also observed were: Nutritional (cachexia) 10% (5/50), undetermined 10% (5/50), digestive (enteritis and hepatitis) 6% (3/50), circulatory (shock) 6% (3/50), metabolic (stress) 4% (2/50) and neoplasia (lymphoma), observed in a single case. We believe that the analysis of the data obtained in this study may provide an overview of the diseases that wild individuals of these species can present in stranding situations and during rehabilitation. Quantifying and understanding the causes of strandings in pinnipeds, will provide important data for rehabilitation centers, which in turn may use this information to plan appropriate veterinary care
5

Órgãos genitais femininos do Lobo-marinho-sul-americano (Arctocephalus australis): uma abordagem morfofuncional / Female genital organs of the South-American-fur-seal (Arctocephalus australis): a morphofunctional approach

Machado, Alex Sander Dias 17 December 2009 (has links)
O Lobo-marinho-sul-americano (A. australis) apresenta particularidades em seu ciclo reprodutivo que revelam sua interação com o ecossistema onde habita. Dentre estas podemos citar o intervalo entre partos de 12 meses, a sincronização dos partos e cópulas no início do verão, umlongo período de diapausa e uma implantação do blastocisto no inicio do inverno, que ocorre 4 a 5 meses após a cópula. A anatomia e fisiologia reprodutivas desta espécie ainda não foram profundamente estudadas. O presente trabalho tem como objetivo, a partir do emprego de métodos não invasivos de pesquisa, descrever a anatomia, histologia, quando possível a ultraestrutura, e a vascularização arterial dos órgãos genitais femininos, bem como investigar proteínas e RNAs mensageiros de fatores de crescimento relacionados à vascularização nestes tecidos. Os dados morfológicos foram correlacionados com dados ambientais, oriundos de estações climatológicas próximas à área da colônia estudada. O A. australis apresenta especializações morfológicas passíveis de correlação com o ambiente, hábitos reprodutivos e ciclo reprodutivo sazonal. Estas estruturas foram identificadas como importantes em momentos específicos da biologia reprodutiva e auxiliam na manutenção do status de conservação da espécie. Análises dos dados climatológicos e sua relação com as variações durante o ano revelam que os eventos do parto, cópula e implantação embrionária, ocorrem em momentos onde as maiores variações ambientais acontecem. Os dados morfológicos revelam que existe uma interação entre o ciclo reprodutivo e as especializações anatômicas dos órgãos genitais femininos / The South-American-fur-seal (A.australis) presents unique features in its reproductive cycle, which reflect their interaction with the ecosystem where it lives. The parturition interval of 12 months, synchronization of parturition and copulation in the beginning of the summer, long diapause and implantation of the blastocyst in the beginning of the winter, which occurs 4 to 5 months after copulation are some of these features. The anatomy and reproductive physiology of this species have not been widely studied. This work describes the anatomy, histology, some ultrastructural characteristics, and the main arterial vascularization of the female genital organs using non invasive methods. Moreover, this study investigates the proteins and messenger RNAs of growth factors which are related to vascularization in these tissues. An association between morphological and environmental data from climatology stations near the area of the studied colony was investigated. A. australis presented morphological specialization in genital organs, which might be related to the environment, reproductive habits and seasonal reproductive cycle. Some of these identified structures are essential in specific stages of A. australis reproductive biology, and play an important role in the maintenance and conservation status of this species. Analysis of climatological data and their relation with changes over the year showed that parturition, copulation and embrionary implantation occur in time periods where the highest environmental variations take place. Morphological data revealed an interaction between the reproductive cycle and the anatomic specialization of female genital organs
6

Estudo do sistema reprodutor masculino do Lobo-Marinho-do- Sul (Arctocephalus australis) / Study of the male reproductive system of Southern-Fur-Seal (Arctocephalus australis)

Machado, Alex Sander Dias 31 May 2006 (has links)
O Lobo-Marinho-do-Sul (Arctocephalus australis), carnívoro, caniforme, membro da superfamília dos Focóides, família Otaridae, é o mais comum mamífero marinho pertencente à fauna brasileira. É freqüentemente avistado, nos meses de outono e inverno na costa do Brasil, desde o Rio de Janeiro até o Rio Grande do Sul. Ainda é discutido se algum dia este animal já possuiu colônias reprodutivas neste país. É histórica a grande pressão antrópica que esta espécie recebeu, sendo explorado pelas populações litorâneas, para aproveitamento de sua pele, óleo e carne desde a antiguidade. No Uruguai, foram por muitos séculos abatidos em números que variavam em torno de 10 mil animais por ano, com o intuito de aproveitamento de sua pele para a confecção de casacos e testículos, para confecção de elixires no Oriente. Porém, deixou de ser explorado comercialmente naquele país na década de 80 e desde então seu número vem aumentando, e por isso especula-se sobre o surgimento de novos sítios reprodutivos em ilhas pedregosas, típicas de sua preferência. É possível até que estuários como o de Cananéia no litoral sul do Estado de São Paulo - BR, possam receber esta espécie nos meses de verão, o que, de acordo com a sazonalidade de sua reprodução, ocorre nesta época. Esse novo "pólo reprodutivo" pode representar um desbravamento de novas áreas (ou mesmo retorno a antigas áreas) pela espécie. É ainda muito escassa a literatura sobre esta espécie e poucos pesquisadores brasileiros a conhecem. Este trabalho buscou através da coleta de indivíduos (cinco jovens e um adulto) em óbito recente, por causas naturais, contribuir com conhecimentos anatômicos, histológicos, ultraestruturais e imuno-histoquímicos do sistema reprodutor masculino do Arctocephalus australis de animais jovens e adultos. Os resultados demonstraram muitas vezes a singularidade da espécie estudada: expressiva queratinização da camada córnea do epitélio escrotal e forte coloração negra nesta região; diferença estrutural existente entre as túnicas albugínea do testículo e do pênis: na primeira observaram-se fibras elásticas bem distribuídas e ausência destas fibras na segunda; ausência de ampolas nos ductos deferentes; uretra pélvica pequena; bulbo do pênis ventral aos pilares penianos e posicionamento singular do seu osso peniano; glande do pênis petaliforme. Encontramos um grande grau de adaptação do sistema reprodutor do macho ao da fêmea, nas duas idades estudadas, demonstrando que a evolução foi direcionada para o ciclo reprodutivo do tipo monoéstrico-estacional, de modo a otimizar a cópula e o volume do ejaculado, garantindo a deposição do sêmem o mais próximo possível do óstio uterino externo da fêmea, e conseqüentemente uma maior taxa de concepção. / The Southern-Fur-Seal (Arctocephalus australis) Carnivora, Caniform, member of the Superfamily Focoidae, Family Otaridae, is the most common marine mammal in brazilian sees, frequently seen in the months of autumn and winter in the coast from Rio de Janeiro until Rio Grande do Sul. There are controversies if some day A. australis already possessed reproductive colonies in this country. The great antropic pressure over the species is historical, being explored by cost populations because of its skin, oil, and meat. In Uruguay, it was slaughtered for many centuries in numbers that reached 10 000 animals per year: the skin was used for the confection of coats and testis, for elixir in the East. However, since the beginning of the decade of 80, commercial exploitation stopped and its number started increasing. Therefore one speculates on the sprouting of new reproductive places in stony islands, typical of its preference, and it is possible that estuaries like Cananéia, in the south coast of the State of São Paulo - BR, started to receiving this species in the summer months, what is in accordance with the reproductive season, which occurs at this time of the year. It can represent an opening of new areas (or even a return the old areas) for the species. Literature is still very scarce on this species and few brazilian researchers know about it. For developing this work, six recent dead for natural causes individuals (five young and one adult) were collected and the reproductive tract was submitted to anatomical, histological, ultrastructural and immunohistochemistry approaches aiming to improve the knowledge about the male reproductive system of the Arctocephalus australis of two ages. Results pointed towards peculiarities of the studied species: expressive keratinization of scrotal epithelium; structural differences between the tunica albuginea in the testis and penis: only in the testis elastic fibers could be observed; no ductus deferens ampulae, small pelvic urethra; glans penis in flower shape. We found a great degree of adaptation of the reproductive system of the male to the one of the female, in the two ages studied, demonstrating that the evolutive orientation was in direction of sazonal-monoestric reproductive cycle, in order to optimize copulation and the volume of the semen, guaranteeing the deposition of the semen as next as possible to the external female uterine ostium and consequently a bigger tax of conception.
7

Órgãos genitais femininos do Lobo-marinho-sul-americano (Arctocephalus australis): uma abordagem morfofuncional / Female genital organs of the South-American-fur-seal (Arctocephalus australis): a morphofunctional approach

Alex Sander Dias Machado 17 December 2009 (has links)
O Lobo-marinho-sul-americano (A. australis) apresenta particularidades em seu ciclo reprodutivo que revelam sua interação com o ecossistema onde habita. Dentre estas podemos citar o intervalo entre partos de 12 meses, a sincronização dos partos e cópulas no início do verão, umlongo período de diapausa e uma implantação do blastocisto no inicio do inverno, que ocorre 4 a 5 meses após a cópula. A anatomia e fisiologia reprodutivas desta espécie ainda não foram profundamente estudadas. O presente trabalho tem como objetivo, a partir do emprego de métodos não invasivos de pesquisa, descrever a anatomia, histologia, quando possível a ultraestrutura, e a vascularização arterial dos órgãos genitais femininos, bem como investigar proteínas e RNAs mensageiros de fatores de crescimento relacionados à vascularização nestes tecidos. Os dados morfológicos foram correlacionados com dados ambientais, oriundos de estações climatológicas próximas à área da colônia estudada. O A. australis apresenta especializações morfológicas passíveis de correlação com o ambiente, hábitos reprodutivos e ciclo reprodutivo sazonal. Estas estruturas foram identificadas como importantes em momentos específicos da biologia reprodutiva e auxiliam na manutenção do status de conservação da espécie. Análises dos dados climatológicos e sua relação com as variações durante o ano revelam que os eventos do parto, cópula e implantação embrionária, ocorrem em momentos onde as maiores variações ambientais acontecem. Os dados morfológicos revelam que existe uma interação entre o ciclo reprodutivo e as especializações anatômicas dos órgãos genitais femininos / The South-American-fur-seal (A.australis) presents unique features in its reproductive cycle, which reflect their interaction with the ecosystem where it lives. The parturition interval of 12 months, synchronization of parturition and copulation in the beginning of the summer, long diapause and implantation of the blastocyst in the beginning of the winter, which occurs 4 to 5 months after copulation are some of these features. The anatomy and reproductive physiology of this species have not been widely studied. This work describes the anatomy, histology, some ultrastructural characteristics, and the main arterial vascularization of the female genital organs using non invasive methods. Moreover, this study investigates the proteins and messenger RNAs of growth factors which are related to vascularization in these tissues. An association between morphological and environmental data from climatology stations near the area of the studied colony was investigated. A. australis presented morphological specialization in genital organs, which might be related to the environment, reproductive habits and seasonal reproductive cycle. Some of these identified structures are essential in specific stages of A. australis reproductive biology, and play an important role in the maintenance and conservation status of this species. Analysis of climatological data and their relation with changes over the year showed that parturition, copulation and embrionary implantation occur in time periods where the highest environmental variations take place. Morphological data revealed an interaction between the reproductive cycle and the anatomic specialization of female genital organs
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Estudo do sistema reprodutor masculino do Lobo-Marinho-do- Sul (Arctocephalus australis) / Study of the male reproductive system of Southern-Fur-Seal (Arctocephalus australis)

Alex Sander Dias Machado 31 May 2006 (has links)
O Lobo-Marinho-do-Sul (Arctocephalus australis), carnívoro, caniforme, membro da superfamília dos Focóides, família Otaridae, é o mais comum mamífero marinho pertencente à fauna brasileira. É freqüentemente avistado, nos meses de outono e inverno na costa do Brasil, desde o Rio de Janeiro até o Rio Grande do Sul. Ainda é discutido se algum dia este animal já possuiu colônias reprodutivas neste país. É histórica a grande pressão antrópica que esta espécie recebeu, sendo explorado pelas populações litorâneas, para aproveitamento de sua pele, óleo e carne desde a antiguidade. No Uruguai, foram por muitos séculos abatidos em números que variavam em torno de 10 mil animais por ano, com o intuito de aproveitamento de sua pele para a confecção de casacos e testículos, para confecção de elixires no Oriente. Porém, deixou de ser explorado comercialmente naquele país na década de 80 e desde então seu número vem aumentando, e por isso especula-se sobre o surgimento de novos sítios reprodutivos em ilhas pedregosas, típicas de sua preferência. É possível até que estuários como o de Cananéia no litoral sul do Estado de São Paulo - BR, possam receber esta espécie nos meses de verão, o que, de acordo com a sazonalidade de sua reprodução, ocorre nesta época. Esse novo "pólo reprodutivo" pode representar um desbravamento de novas áreas (ou mesmo retorno a antigas áreas) pela espécie. É ainda muito escassa a literatura sobre esta espécie e poucos pesquisadores brasileiros a conhecem. Este trabalho buscou através da coleta de indivíduos (cinco jovens e um adulto) em óbito recente, por causas naturais, contribuir com conhecimentos anatômicos, histológicos, ultraestruturais e imuno-histoquímicos do sistema reprodutor masculino do Arctocephalus australis de animais jovens e adultos. Os resultados demonstraram muitas vezes a singularidade da espécie estudada: expressiva queratinização da camada córnea do epitélio escrotal e forte coloração negra nesta região; diferença estrutural existente entre as túnicas albugínea do testículo e do pênis: na primeira observaram-se fibras elásticas bem distribuídas e ausência destas fibras na segunda; ausência de ampolas nos ductos deferentes; uretra pélvica pequena; bulbo do pênis ventral aos pilares penianos e posicionamento singular do seu osso peniano; glande do pênis petaliforme. Encontramos um grande grau de adaptação do sistema reprodutor do macho ao da fêmea, nas duas idades estudadas, demonstrando que a evolução foi direcionada para o ciclo reprodutivo do tipo monoéstrico-estacional, de modo a otimizar a cópula e o volume do ejaculado, garantindo a deposição do sêmem o mais próximo possível do óstio uterino externo da fêmea, e conseqüentemente uma maior taxa de concepção. / The Southern-Fur-Seal (Arctocephalus australis) Carnivora, Caniform, member of the Superfamily Focoidae, Family Otaridae, is the most common marine mammal in brazilian sees, frequently seen in the months of autumn and winter in the coast from Rio de Janeiro until Rio Grande do Sul. There are controversies if some day A. australis already possessed reproductive colonies in this country. The great antropic pressure over the species is historical, being explored by cost populations because of its skin, oil, and meat. In Uruguay, it was slaughtered for many centuries in numbers that reached 10 000 animals per year: the skin was used for the confection of coats and testis, for elixir in the East. However, since the beginning of the decade of 80, commercial exploitation stopped and its number started increasing. Therefore one speculates on the sprouting of new reproductive places in stony islands, typical of its preference, and it is possible that estuaries like Cananéia, in the south coast of the State of São Paulo - BR, started to receiving this species in the summer months, what is in accordance with the reproductive season, which occurs at this time of the year. It can represent an opening of new areas (or even a return the old areas) for the species. Literature is still very scarce on this species and few brazilian researchers know about it. For developing this work, six recent dead for natural causes individuals (five young and one adult) were collected and the reproductive tract was submitted to anatomical, histological, ultrastructural and immunohistochemistry approaches aiming to improve the knowledge about the male reproductive system of the Arctocephalus australis of two ages. Results pointed towards peculiarities of the studied species: expressive keratinization of scrotal epithelium; structural differences between the tunica albuginea in the testis and penis: only in the testis elastic fibers could be observed; no ductus deferens ampulae, small pelvic urethra; glans penis in flower shape. We found a great degree of adaptation of the reproductive system of the male to the one of the female, in the two ages studied, demonstrating that the evolutive orientation was in direction of sazonal-monoestric reproductive cycle, in order to optimize copulation and the volume of the semen, guaranteeing the deposition of the semen as next as possible to the external female uterine ostium and consequently a bigger tax of conception.
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Estudo de causa mortis de ARCTOCEPHALUS AUSTRALIS (ZIMMERMANN, 1783) (LOBO-MARINHO-SUL-AMERICANO) no litoral norte do Rio Grande do Sul, Brasil

Amorim, Derek Blaese de January 2014 (has links)
Arctocephalus australis (Zimmermann, 1783) (lobo-marinho-sul-americano), é um carnívoro marinho com ampla distribuição, que ocorre nas costas leste e oeste da América do Sul, desde o Peru até o Brasil. O maior número de registros de espécimes de A. australis no Brasil ocorre no estado do Rio Grande do Sul, onde estão localizadas as duas principais áreas de concentração de pinípedes no País. Apesar de não haver colônias reprodutivas da espécie no litoral brasileiro, todos os anos, principalmente no período entre junho e outubro, inúmeros animais (vivos e mortos) são encontrados no litoral do País. O objetivo deste trabalho foi caracterizar as causas de morte mais comuns nos animais que ocorrem no litoral norte do estado do Rio Grande do Sul em 2012 e 2013. Para isso, foi realizada necropsia em 50 animais encontrados mortos na praia. Dos animais necropsiados, 30% tiveram a morte associada com trauma severo, apresentando laceração da musculatura, hemorragia extensa e politraumatismo e 8% trauma severo com laceração da musculatura e hemorragia extensa. Ainda 14% tiveram como causa mortis alterações no trato respiratório, 6% apresentaram alterações no trato gastrointestinal, 4% no sistema muscular, 4% no sistema nervoso central, 2% no sistema hepático e 2% com alterações no trato reprodutivo. Ainda, 18% tiveram a morte associada à caquexia e em 12% não foi possível concluir a causa da morte. Os principais achados são discutidos, bem como fatores antrópicos e não antrópicos que podem ter causado ou contribuído para o óbito dos animais.
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Estudo de causa mortis de ARCTOCEPHALUS AUSTRALIS (ZIMMERMANN, 1783) (LOBO-MARINHO-SUL-AMERICANO) no litoral norte do Rio Grande do Sul, Brasil

Amorim, Derek Blaese de January 2014 (has links)
Arctocephalus australis (Zimmermann, 1783) (lobo-marinho-sul-americano), é um carnívoro marinho com ampla distribuição, que ocorre nas costas leste e oeste da América do Sul, desde o Peru até o Brasil. O maior número de registros de espécimes de A. australis no Brasil ocorre no estado do Rio Grande do Sul, onde estão localizadas as duas principais áreas de concentração de pinípedes no País. Apesar de não haver colônias reprodutivas da espécie no litoral brasileiro, todos os anos, principalmente no período entre junho e outubro, inúmeros animais (vivos e mortos) são encontrados no litoral do País. O objetivo deste trabalho foi caracterizar as causas de morte mais comuns nos animais que ocorrem no litoral norte do estado do Rio Grande do Sul em 2012 e 2013. Para isso, foi realizada necropsia em 50 animais encontrados mortos na praia. Dos animais necropsiados, 30% tiveram a morte associada com trauma severo, apresentando laceração da musculatura, hemorragia extensa e politraumatismo e 8% trauma severo com laceração da musculatura e hemorragia extensa. Ainda 14% tiveram como causa mortis alterações no trato respiratório, 6% apresentaram alterações no trato gastrointestinal, 4% no sistema muscular, 4% no sistema nervoso central, 2% no sistema hepático e 2% com alterações no trato reprodutivo. Ainda, 18% tiveram a morte associada à caquexia e em 12% não foi possível concluir a causa da morte. Os principais achados são discutidos, bem como fatores antrópicos e não antrópicos que podem ter causado ou contribuído para o óbito dos animais.

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