RESUMEN

Thoracic limbs are extremely versatile and exhibit informative characteristics about habits of the Carnivora order in the wild. Despite this relevance, comparative studies with quantitative variables on thoracic limb muscles are still scarce in carnivorans. The aims of this study were to measure the mass of the intrinsic muscles of the thoracic limb of neotropical species of the Carnivora order and to establish comparative conjectures. For this purpose, 39 thoracic limbs of 10 neotropical carnivorans species were dissected. The mass of each muscle was measured on a digital scale, muscles were grouped by function, and the mass average percentage that each functional group of muscles occupied in the thoracic limb was calculated. The data of the present study was added to that available in the literature for 22 other carnivoran species. Three groups of species were considered: Canidae, Musteloidea, and Feliformia. Comparatively, the eight canid species included in this analyses concentrate muscle mass proximally in the thoracic limb to prioritize essential cursoriality. The nine musteloids had more muscle mass in the distal muscles due to the demand for versatility and manual strength, and the 14 Feliformia species exhibited an intermediate trend. The analysis of clusters revealed a great overlap of the percentage distribution of muscle mass with the phylogeny previously established for carnivorans. It could be verified that the distribution of muscle masses meets the demand of the locomotor habits of the species up to a certain level, from which phylogeny begins to limit morphological adaptations.

Os membros torácicos são extremamente versáteis e exibem características informativas sobre os hábitos das espécies da ordem Carnivora em vida livre. A despeito desta relevência, estudos comparativos com variéveis quantitativas dos músculos do membro torácico são escassos em carnívoros. Os objetivos deste estudo foram aferir a massa dos músculos intrínsecos do membro torácico de espécies neotropicais da ordem Carnivora e estabelecer conjecturas comparativas. Para este fim, foram dissecados 39 membros torácicos de dez espécies de carnívoros neotropicais. A massa de cada músculo foi mensurada em uma balança digital, os músculos foram agrupados por função e calculou-se a massa percentual média a que cada grupo funcional de músculos correspondia no membro torácico. Os dados do presente estudo foram analisados conjuntamente às informações disponíveis na literatura para outras 22 espécies da ordem Carnivora. Três grupos de espécies foram considerados: Canidae, Musteloidea e Feliformia. Comparativamente, as oito espécies de canídeos incluídas nesta análise demonstraram concentração de massa muscular mais proximalmente no membro torácico em razão dos hábitos essencialmente cursoriais. As nove espécies da superfamília Musteloidea exibiram mais massa nos músculos distais devido à maior demanda por versatilidade e força manual. As 14 espécies da subordem Feliformia apresentaram um padrão intermediário. A análise de clusters revelou nítida sobreposição entre o percentual de distribuição da massa muscular com a filogenia previamente estabelecida para a ordem Carnivora. Verificou-se que a distribuição da massa dos músculos atende à demanda dos hábitos locomotores das espécies até um certo nível, a partir do qual a filogenia começa a limitar as adaptações morfológicas.

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RESUMEN

The morphological knowledge of the salivary glands in wild species is fundamental, since these studiescan be used as conservation strategies, clinical treatments and the preservation of species threatened with extinction. Thus, the aim of the study was to anatomically describe the larger salivary glands: parotid, mandibular, sublingual and molar of the jaguar. For this, two specimens of puma (Puma concolor) were used, after death by road traffic accident, donated by the Clinical Surgical Service Department of the Veterinary Hospital Dr. Halim Atique (UNIRP). The animals were fixed with 10% aqueous formaldehyde solution, dissected, descriptively analyzed and photographed. Morphologically, the parotid gland is grayish-yellow in color, distinctly lobulated, and has a semilunar shape. This gland is located in the posterolateral region of the face and at its ventral end we observe the parotid duct. The mandibular gland presents a slightly rounded outline, a grayish color and its surface is covered by a capsule of connective tissue. This gland is located in the posterolateral region of the face and we find the mandibular duct at its ventral end. The monostomatic sublingual gland is located on the rostral border of the mandibular gland and it is covered by the mandibular lymph nodes. The molar gland is a yellowish-gray membranous protuberance, elongated, with rectangular shape and it lies dorsally to the labial commissure. Based on the dissections, we conclude that the morphological and topographic characteristics of salivary glands of puma follow the same structural pattern described for other species of carnivorous mammals (domestic and wild).(AU)

O conhecimento morfológico das glândulas salivares em espécies silvestres é fundamental, pois podem ser utilizadas como estratégias de conservação, tratamentos clínicos e preservação de espécies ameaçadas de extinção. Dessa forma, o objetivo do estudo foi descrever anatomicamente as glândulas salivares maiores: parótida, mandibular, sublingual e molar da onça-parda. Para isso, foram utilizados dois espécimes de onça-parda (Puma concolor), após morte por atropelamento, doados pelo Setor de Atendimento Clínico Cirúrgico de Animais Selvagens (SACCAS) do Hospital Veterinário Dr. HalimAtique (UNIRP). Os animais foram fixados com solução aquosa de formol a 10%, dissecados, analisados descritivamente e fotografados. Morfologicamente, a glândula parótida possui uma coloração cinza amarelada, é distintamente lobulada e apresenta um formato semilunar. Essa glândula localiza-se na região póstero-dorsal da face, e na sua extremidade ventral observamos o ducto parotídeo. A glândula mandibular apresenta um contorno levemente arredondado, coloração acinzentada e sua superfície é revestida por uma cápsula de tecido conjuntivo. Essa glândula situa-se na região póstero-ventral da face e na sua extremidade ventral encontramos o ducto mandibular. A glândula sublingual monostomática está localizada na borda rostral da glândula mandibular e apresenta-se coberta pelos linfonodos mandibulares. A glândula molar é uma protuberância membranosa de coloração cinza amarelada, formato retangular alongado que fica situada ventralmente a comissura labial. Fundamentado nas dissecações, concluímos que as características morfológicas e topográficas das glândulas salivares da onça-parda seguem o mesmo padrão estrutural descrito para outras espécies de mamíferos carnívoros (domésticos e silvestres).(AU)

Asunto(s)

RESUMEN

The morphological knowledge of the salivary glands in wild species is fundamental, since these studiescan be used as conservation strategies, clinical treatments and the preservation of species threatened with extinction. Thus, the aim of the study was to anatomically describe the larger salivary glands: parotid, mandibular, sublingual and molar of the jaguar. For this, two specimens of puma (Puma concolor) were used, after death by road traffic accident, donated by the Clinical Surgical Service Department of the Veterinary Hospital Dr. Halim Atique (UNIRP). The animals were fixed with 10% aqueous formaldehyde solution, dissected, descriptively analyzed and photographed. Morphologically, the parotid gland is grayish-yellow in color, distinctly lobulated, and has a semilunar shape. This gland is located in the posterolateral region of the face and at its ventral end we observe the parotid duct. The mandibular gland presents a slightly rounded outline, a grayish color and its surface is covered by a capsule of connective tissue. This gland is located in the posterolateral region of the face and we find the mandibular duct at its ventral end. The monostomatic sublingual gland is located on the rostral border of the mandibular gland and it is covered by the mandibular lymph nodes. The molar gland is a yellowish-gray membranous protuberance, elongated, with rectangular shape and it lies dorsally to the labial commissure. Based on the dissections, we conclude that the morphological and topographic characteristics of salivary glands of puma follow the same structural pattern described for other species of carnivorous mammals (domestic and wild).

O conhecimento morfológico das glândulas salivares em espécies silvestres é fundamental, pois podem ser utilizadas como estratégias de conservação, tratamentos clínicos e preservação de espécies ameaçadas de extinção. Dessa forma, o objetivo do estudo foi descrever anatomicamente as glândulas salivares maiores: parótida, mandibular, sublingual e molar da onça-parda. Para isso, foram utilizados dois espécimes de onça-parda (Puma concolor), após morte por atropelamento, doados pelo Setor de Atendimento Clínico Cirúrgico de Animais Selvagens (SACCAS) do Hospital Veterinário Dr. HalimAtique (UNIRP). Os animais foram fixados com solução aquosa de formol a 10%, dissecados, analisados descritivamente e fotografados. Morfologicamente, a glândula parótida possui uma coloração cinza amarelada, é distintamente lobulada e apresenta um formato semilunar. Essa glândula localiza-se na região póstero-dorsal da face, e na sua extremidade ventral observamos o ducto parotídeo. A glândula mandibular apresenta um contorno levemente arredondado, coloração acinzentada e sua superfície é revestida por uma cápsula de tecido conjuntivo. Essa glândula situa-se na região póstero-ventral da face e na sua extremidade ventral encontramos o ducto mandibular. A glândula sublingual monostomática está localizada na borda rostral da glândula mandibular e apresenta-se coberta pelos linfonodos mandibulares. A glândula molar é uma protuberância membranosa de coloração cinza amarelada, formato retangular alongado que fica situada ventralmente a comissura labial. Fundamentado nas dissecações, concluímos que as características morfológicas e topográficas das glândulas salivares da onça-parda seguem o mesmo padrão estrutural descrito para outras espécies de mamíferos carnívoros (domésticos e silvestres).

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The clavicle is a bone whose development is related to the versatility of the thoracic limbs in mammals. Studies with vestigial structures are scarce and controversial, especially in the order Carnivora. The objective of this study was to verify the presence and to investigate the shape and constitution of the clavicle in neotropical carnivores. In order to do this, 108 cadavers of 19 different species were collected dead on highways and were analyzed. The clavicles were submitted to dissections, longitudinal length measurements, radiographs, histological sections and, in some cases, diaphanization. Sixteen of the 19 species had clavicles in both sides, being significantly larger (P < 0.05) and distinctly more radiopaque in the felids than in the other families. There were no macro or microscopic evidence of clavicle in the specimens of Nasua nasua (n = 6), Conepatus semistriatus (n = 2), and Conepatus chinga (n = 1). The clavicle of the males of Lycalopex gymnocercus, Galictis cuja, and Leopardus geoffroyi was significantly larger (P < 0.05). The predominating contour of the clavicles was a thin stick with cranial convexity. The histological sections demonstrated compact bone consisting of trabecula and lamellae filled by bone marrow and different levels of occupation by chondroid matrix. It can be proposed the clavicles of the order Carnivora, although vestigial and rarely absent, have their presence, constitution and shape more associated with the phylogenetic proximity and evolutionary history of the species than to the variety of movements the thoracic limbs perform in free-living conditions. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1831-1841, 2020. © 2019 American Association for Anatomy.

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Nenhuma característica dos seres vivos é tão primordial quanto a respiração, e os pulmões são os principais órgãos do sistema respiratório. Este estudo tem por objetivo descrever os aspectos macroscópicos da traqueia, dos brônquios e dos lobos pulmonares bem como os aspectos microscópicos dos brônquios pulmonares do mão-pelada e compará-los com dados da literatura de estudos realizados com mamíferos silvestres e domésticos. Utilizaram-se três exemplares de Procyon cancrivorus, que foram fixados em solução aquosa de formaldeído a 10%. Os pulmões e a traqueia foram dissecados e fotografados com câmera fotográfica digital (Câmera Sony a200, 10.2mpx). Para a identificação das características microscópicas, foram coletados fragmentos de cada brônquio seguindo as técnicas de rotina histológica. O pulmão do Procyon cancrivorus se divide em quatro lobos direito e dois lobos esquerdo e a traqueia apresenta cerca de 31 a 34 anéis. Os brônquios extrapulmonares se dividem em direito e esquerdo; o direito se subdivide em brônquios lobares cranial, médio, acessório e caudal, e o esquerdo em lobares cranial e caudal, com seus respectivos brônquios segmentares. Microscopicamente, os brônquios apresentam um epitélio prismático pseudoestratificado ciliado com células caliciformes e feixes de fibras de musculatura lisa, placas de cartilagem hialina e fibras elásticas. O conhecimento da morfologia desses órgãos nas espécies silvestres auxilia em estudos descritivos e/ou comparativos entre espécies.

No characteristic of living beings is as primal as breathing, and the lungs are the main organs in the respiratory system. This study aims to describe the macroscopic aspects of the trachea, bronchus and lung lobes and microscopic aspects of the bronchi of raccoon lungs and compare with data from the literature studies performed with wild and domestic mammals. We used three samples of Procyon cancrivorus, which were fixed in aqueous 10% formaldehyde, lungs and trachea were dissected and photographed with a digital camera (Sony a200 Camera, 10.2mpx). For the identification of microscopic characteristics, fragments were collected from each bronchus following routine histological techniques. The Procyon cancrivorus lung is divided into four lobes, with two right and left lobes. The trachea has about 31-34 rings. The extrapulmonary bronchi divides into left and right, where the right is divided into lobar bronchi cranial, middle, accessory and caudal lobes and the left in cranial and caudal, with their respective segmental bronchi. Microscopically the bronchial epithelium has prismatic pseudo-ciliated and goblet cells with bundles of smooth muscle fibers, plates of hyaline cartilage and elastic fibers. Knowledge of the morphology of these organs in wild species helps us in descriptive studies and / or comparisons between species.

Asunto(s)

RESUMEN

Nenhuma característica dos seres vivos é tão primordial quanto a respiração, e os pulmões são os principais órgãos do sistema respiratório. Este estudo tem por objetivo descrever os aspectos macroscópicos da traqueia, dos brônquios e dos lobos pulmonares bem como os aspectos microscópicos dos brônquios pulmonares do mão-pelada e compará-los com dados da literatura de estudos realizados com mamíferos silvestres e domésticos. Utilizaram-se três exemplares de Procyon cancrivorus, que foram fixados em solução aquosa de formaldeído a 10%. Os pulmões e a traqueia foram dissecados e fotografados com câmera fotográfica digital (Câmera Sony a200, 10.2mpx). Para a identificação das características microscópicas, foram coletados fragmentos de cada brônquio seguindo as técnicas de rotina histológica. O pulmão do Procyon cancrivorus se divide em quatro lobos direito e dois lobos esquerdo e a traqueia apresenta cerca de 31 a 34 anéis. Os brônquios extrapulmonares se dividem em direito e esquerdo; o direito se subdivide em brônquios lobares cranial, médio, acessório e caudal, e o esquerdo em lobares cranial e caudal, com seus respectivos brônquios segmentares. Microscopicamente, os brônquios apresentam um epitélio prismático pseudoestratificado ciliado com células caliciformes e feixes de fibras de musculatura lisa, placas de cartilagem hialina e fibras elásticas. O conhecimento da morfologia desses órgãos nas espécies silvestres auxilia em estudos descritivos e/ou comparativos entre espécies.(AU)

No characteristic of living beings is as primal as breathing, and the lungs are the main organs in the respiratory system. This study aims to describe the macroscopic aspects of the trachea, bronchus and lung lobes and microscopic aspects of the bronchi of raccoon lungs and compare with data from the literature studies performed with wild and domestic mammals. We used three samples of Procyon cancrivorus, which were fixed in aqueous 10% formaldehyde, lungs and trachea were dissected and photographed with a digital camera (Sony a200 Camera, 10.2mpx). For the identification of microscopic characteristics, fragments were collected from each bronchus following routine histological techniques. The Procyon cancrivorus lung is divided into four lobes, with two right and left lobes. The trachea has about 31-34 rings. The extrapulmonary bronchi divides into left and right, where the right is divided into lobar bronchi cranial, middle, accessory and caudal lobes and the left in cranial and caudal, with their respective segmental bronchi. Microscopically the bronchial epithelium has prismatic pseudo-ciliated and goblet cells with bundles of smooth muscle fibers, plates of hyaline cartilage and elastic fibers. Knowledge of the morphology of these organs in wild species helps us in descriptive studies and / or comparisons between species.(AU)

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RESUMEN

Este estudo teve o objetivo de descrever a origem e ramificação dos nervos de vinte plexos braquiais de cachorro-do-mato (Cerdocyon thous). Dez animais da espécie, obtidos post mortem por atropelamento em rodovias, foram utilizados para o estudo, de acordo com a autorização do IBAMA/SISBIO nº33667-1. Depois de coletados, os cadáveres foram fixados em solução de formaldeído a 50% e conservados por pelo menos 14 dias em solução de formaldeído a 10% antes das dissecções. Após remoção da pele, incisões na musculatura peitoral e afastamento dos membros, acessou-se o espaço axilar e os nervos do plexo tiveram seu trajeto dissecados individualmente até sua inserção muscular. Para melhorar a visualização dos ramos ventrais cervicais e torácicos que originavam cada nervo, removeram-se a musculatura que encobria os forames intervertebrais, os processos transversos e os corpos vertebrais ventralmente, expondo inclusive a medula espinhal. Registros fotográficos e desenhos esquemáticos documentaram a origem e ramificação dos nervos. Os vinte plexos braquiais foram resultantes das conexões entre os ramos ventrais dos três últimos nervos espinhais cervicais (C6, C7 e C8) e do primeiro torácico (T1). Estes ramos derivaram os nervos supra-escapular, subescapular, axilar, musculocutâneo, radial, mediano, ulnar para a musculatura intrínseca e os nervos braquiocefálico, toracodorsal, torácico lateral, torácico longo, peitoral cranial e peitoral caudal para a musculatura extrínseca do membro torácico. Constatou-se que os ramos ventrais de C7 foram os que mais contribuíram na formação de nervos (61,5%), seguido de C8 (55,4%), de T1 (41,2%) e de C6 (30,8%). O teste t de comparação entre as médias, ao nível de significância de 5%, não demonstrou diferenças na origem do plexo quando comparados os antímeros e os sexos. Do total dos 260 nervos dissecados, 68,8% foram originados pela combinação de dois ou três ramos, enquanto apenas 31,2% tiveram formação por um único ramo. A combinação entre C8 e T1 foi a que mais formou nervos para o plexo (23,8%) nesta espécie. Quando comparadas a origem, ramificação e área de inervação do plexo braquial do C. thous com outras espécies domésticas e silvestres, verificou-se maior semelhança com o cão doméstico. Os resultados deste estudo podem embasar o diagnóstico de disfunções neuromusculares, as técnicas de bloqueios anestésicos e análises morfofuncionais comparativas envolvendo esta espécie.

This study aimed to describe the origin and branching of nerves from twenty brachial plexuses of crab-eating foxes (Cerdocyon thous). Ten animals of the species, obtained post mortem from being run over on highways, were used for the study, in accordance with the authorization from IBAMA / SISBIO No. 33667-1. Once collected, the cadavers were fixed in 50% formaldehyde and kept for at least 14 days in a solution of 10% formaldehyde before dissections. After removal of skin, incisions in breast muscles and reflection of thoracic limbs allowed access to axillary space and the nerves could have trajects dissected individually to each muscle insertion. To improve visualization of the cervical and thoracic ventral roots that originated every single nerve, muscles that covered the intervertebral foramina, transverse processes and vertebral bodies were removed ventrally and the spinal cord exposed. Schematic drawings and photographic records documented the origin and branching of nerves. The twenty plexuses were resulted from connections between the ventral branches of the last three cervical spinal nerves (C6, C7 and C8) and first thoracic (T1). These branches derived the nerves suprascapular, subscapular, axillary, musculocutaneous, radial, median and ulnar to the intrinsic muscles and brachiocephalic, thoracodorsal, lateral thoracic, long thoracic, cranial and caudal pectoral nerves to the extrinsic muscles of the thoracic limb. It was found that the ventral rami of C7 were the main contributors in the formation of nerves (61.5%), followed by C8 (55.4%), T1 (41.2%) and C6 (30.8%). The t-test comparison between means at a significance level of 5% showed no differences in the origin of plexus when compared antimeres and sexes. Of the total of 260 dissected nerves, 68.8% originated by the combination of two or three roots, while only 31.2% were formed by a single root. The combination between C8 and T1 was the most frequent origin of nerves to the plexus (23.8%) in this species. Comparing the origin, branching and innervation area of the brachial plexus in C. thous with other domestic and wild species, there was a greater similarity with the domestic dog. These results may give the anatomical basis to diagnosis of neuromuscular disorders, anesthetic blocks techniques and comparative morphofunctional analyzes involving this species.

Asunto(s)

RESUMEN

Este estudo teve o objetivo de descrever a origem e ramificação dos nervos de vinte plexos braquiais de cachorro-do-mato (Cerdocyon thous). Dez animais da espécie, obtidos post mortem por atropelamento em rodovias, foram utilizados para o estudo, de acordo com a autorização do IBAMA/SISBIO nº33667-1. Depois de coletados, os cadáveres foram fixados em solução de formaldeído a 50% e conservados por pelo menos 14 dias em solução de formaldeído a 10% antes das dissecções. Após remoção da pele, incisões na musculatura peitoral e afastamento dos membros, acessou-se o espaço axilar e os nervos do plexo tiveram seu trajeto dissecados individualmente até sua inserção muscular. Para melhorar a visualização dos ramos ventrais cervicais e torácicos que originavam cada nervo, removeram-se a musculatura que encobria os forames intervertebrais, os processos transversos e os corpos vertebrais ventralmente, expondo inclusive a medula espinhal. Registros fotográficos e desenhos esquemáticos documentaram a origem e ramificação dos nervos. Os vinte plexos braquiais foram resultantes das conexões entre os ramos ventrais dos três últimos nervos espinhais cervicais (C6, C7 e C8) e do primeiro torácico (T1). Estes ramos derivaram os nervos supra-escapular, subescapular, axilar, musculocutâneo, radial, mediano, ulnar para a musculatura intrínseca e os nervos braquiocefálico, toracodorsal, torácico lateral, torácico longo, peitoral cranial e peitoral caudal para a musculatura extrínseca do membro torácico. Constatou-se que os ramos ventrais de C7 foram os que mais contribuíram na formação de nervos (61,5%), seguido de C8 (55,4%), de T1 (41,2%) e de C6 (30,8%). O teste t de comparação entre as médias, ao nível de significância de 5%, não demonstrou diferenças na origem do plexo quando comparados os antímeros e os sexos. Do total dos 260 nervos dissecados, 68,8% foram originados pela combinação de dois ou três ramos, enquanto apenas 31,2% tiveram formação por um único ramo. A combinação entre C8 e T1 foi a que mais formou nervos para o plexo (23,8%) nesta espécie. Quando comparadas a origem, ramificação e área de inervação do plexo braquial do C. thous com outras espécies domésticas e silvestres, verificou-se maior semelhança com o cão doméstico. Os resultados deste estudo podem embasar o diagnóstico de disfunções neuromusculares, as técnicas de bloqueios anestésicos e análises morfofuncionais comparativas envolvendo esta espécie.(AU)

This study aimed to describe the origin and branching of nerves from twenty brachial plexuses of crab-eating foxes (Cerdocyon thous). Ten animals of the species, obtained post mortem from being run over on highways, were used for the study, in accordance with the authorization from IBAMA / SISBIO No. 33667-1. Once collected, the cadavers were fixed in 50% formaldehyde and kept for at least 14 days in a solution of 10% formaldehyde before dissections. After removal of skin, incisions in breast muscles and reflection of thoracic limbs allowed access to axillary space and the nerves could have trajects dissected individually to each muscle insertion. To improve visualization of the cervical and thoracic ventral roots that originated every single nerve, muscles that covered the intervertebral foramina, transverse processes and vertebral bodies were removed ventrally and the spinal cord exposed. Schematic drawings and photographic records documented the origin and branching of nerves. The twenty plexuses were resulted from connections between the ventral branches of the last three cervical spinal nerves (C6, C7 and C8) and first thoracic (T1). These branches derived the nerves suprascapular, subscapular, axillary, musculocutaneous, radial, median and ulnar to the intrinsic muscles and brachiocephalic, thoracodorsal, lateral thoracic, long thoracic, cranial and caudal pectoral nerves to the extrinsic muscles of the thoracic limb. It was found that the ventral rami of C7 were the main contributors in the formation of nerves (61.5%), followed by C8 (55.4%), T1 (41.2%) and C6 (30.8%). The t-test comparison between means at a significance level of 5% showed no differences in the origin of plexus when compared antimeres and sexes. Of the total of 260 dissected nerves, 68.8% originated by the combination of two or three roots, while only 31.2% were formed by a single root. The combination between C8 and T1 was the most frequent origin of nerves to the plexus (23.8%) in this species. Comparing the origin, branching and innervation area of the brachial plexus in C. thous with other domestic and wild species, there was a greater similarity with the domestic dog. These results may give the anatomical basis to diagnosis of neuromuscular disorders, anesthetic blocks techniques and comparative morphofunctional analyzes involving this species.(AU)

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The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado.

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We analysed mandible shape of the orders Dasyuromorpha, Didelphimorphia, and Carnivora using twodimensional geometric morphometrics, in order to explore the relationship between shape, size, and phylogeny. We studied 541 specimens, covering most of the genera of the terrestrial Carnivora (115 species) and a wide sample of marsupials (36 species). The observed shape variation had an ecological component. As an example, omnivorous carnivores have thick mandibles and large talonids in the carnassials, while hypercarnivores possess short mandibles and reduced talonids. There is also a discrimination between different taxonomic groups (i.e. marsupials and Carnivora), indicating some kind of constraint. Size explains a large percentage of total variance (large species had shorter and stronger mandibles, with anteriorly displaced carnassials), was significant when phylogeny was taken into account with a comparative method, but not when size and shape were optimized on the phylogeny. Carnivora presents a larger disparity and variation in body size, which could be related to the difference in teeth replacement. The optimization of mandible shape on the phylogenetic tree indicates that functional aspects, such as diet, are a key factor in the evolution of the carnivore mandible, but also that there is a phylogenetic pattern that cannot be explained by differences in diet alone.

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A nearly complete skeleton of the new abelisaurid Skorpiovenator bustingorryi is reported here. The holotype was found in Late Cenomanian-Early Turonian outcrops of NW Patagonia, Argentina. This new taxon is deeply nested within a new clade of South American abelisaurids, named Brachyrostra. Within brachyrostrans, the skull shortening and hyperossification of the skull roof appear to be correlated with a progressive enclosure of the orbit, a set of features possibly related to shock-absorbing capabilities. Moreover, the development of horn-like structures and differential cranial thickening appear to be convergently acquired within Abelisauridae. Based on the similarities between Skorpiovenator and carcharodontosaurid tooth morphology, we suggest that isolated teeth originally referred as post-Cenomanian Carcharodontosauridae most probably belong to abelisaurids.

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Se describen los músculos del miembro toracico del puma (Puma concolor). Con este objetivo se hizo una disección en dos pumas adultos,donados por el Servicio Agricola y Ganadero (SAG) a la Universidad Santo Tomás y por el Parque Zoológico Metropolitano a la Universidad de Chile. Los cadaveres fueron conservados mediante metodos anatómicos tradicionales, realizandosela disección muscular de los miembros toracicos. Nuestras observaciones mostraron que los músculos presentes son los mismos que los descritos para otros felinos como el gato doméstico, siendo el grado de desarrollo que alcanza cada músculo, el parametro de variabilidad entre ambas especies. Se destaca, ademas, la presencia del músculo flexor digital superficial, que en textos clasicos es llamado músculo palmar largo.

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Es un hecho notable que la identificación de huesos o fragmentos de éstos contribuye sobremanera en el esclarecimiento de problemas judiciales. Cuando no se dispone del esqueleto o de huesos íntegros, el análisis de características histomorfológicas óseas se torna un factor decisivo en la elucidación de ciertos casos de identificación. El propósito del presente estudio fue ampliar o buscar nuevas posibilidades en la identificación de fragmentos óseos de seres humanos y de otros 19 mamíferos. Así, analizamos los sistemas de Havers, los canales de Havers, los osteocitos y los canalículos de los mismos, del hombre, anta, aracambé, buey, cabra, perro montés, perro, capivara, carnero, cateto, caballo, conejo, cutia, gato, mono-clavo, jaguar, puerco espín, cerdo, oso hormiguero y venado. Fueron analizados cortes histológicos por desgaste del tejido óseo en sentido longitudinal y transversal y analizados con microscopio de luz. Los resultados demuestran con claridad y precisión que el análisis histomorfológico de las estructuras citadas posibilita la identificación y diferenciación de los géneros estudiados o excluyen la posibilidad de que fragmentos óseos examinados pertenezcan al género Homo sapiens

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Captive adult male ocelots (Leopardus pardalis, n = 3), margays (L. wiedii, n = 3) and tigrinas (L. tigrinus, n = 4) in two locations in southern Brazil were studied for 14 consecutive months to evaluate the effect of season on testicular function. Reproductive evaluations, including testicular measurements, electroejaculation and blood collection were conducted monthly. Fecal samples were collected weekly for androgen metabolite analysis to assess testicular steroidogenic activity. Ocelots had the highest number of motile spermatozoa in the ejaculate (114.7+/-15.8 x 10(6); P < 0.05), the highest percentage of morphologically normal spermatozoa (82.4+/-1.2%; P < 0.05) and the highest concentration of fecal androgens (1.71 vs. 0.14 microg/g; P < 0.05). Margays and tigrinas had lower numbers of motile spermatozoa (23.4+/-2.8 x 10(6), 74.2+/-8.9 x 10(6), respectively), lower percentages of morphologically normal spermatozoa (57.4+/-2.8, 59.2+/-3.5%, respectively), and lower fecal androgen concentrations (0.15+/-0.01, 0.23+/-0.01 microg/g, respectively). Serum testosterone concentrations were similar among the three species. Fecal androgen concentrations were not affected by season, with the exception of the ocelot where concentrations were higher (P < 0.05) in the summer. Ejaculates were collected throughout the year; however, peaks in average sperm production were observed during the summer for all species. In summary, this study has identified several species differences in male testicular traits among ocelots, margays and tigrinas. Results of longitudinal reproductive assessments suggest males of each species are capable of breeding throughout the year.

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Studies of the gross morphology and microstructure of teeth have provided a great deal of information about the function and evolution of mammals. Among the structural features studied, the dentinoenamel junction has received relatively little attention. In the present work, we used ground sections to perform a comparative analysis of the structure of the dentinoenamel junction (DEJ) among diverse mammalian species. Among the species studied, only two (human and Miguelsoria parayirunhor) presented a scalloped DEJ. In the other 14 species analyzed, the DEJ surface was formed by tiny spikes and depressions, corresponding to the impression of enamel prisms. Our results show that the topography of the DEJ in the analyzed taxa apparently does not relate to dietary, functional or structural features.

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En los estudios de neurología experimental se ha evitado, en general, utilizar al perro, a pesar que esta especie es una de las favoritas para la fisiología experimental. Esta situación se debe en parte a la variabilidad en la morfometría de su cráneo, pero la causa fundamental es que la investigación se ha realizado en otras especies en las que la anatomía del encéfalo es mejor conocida. Los trabajos de Lim, Liu y Moffit demostraron que la variabilidad de las cabezas de los perros no era necesariamente un obstáculo, y aplicaron en los caninos la técnica estereotáxica de Horsley y Clarke. A partir de tales estudios, se multiplicaron las posibilidades en la investigación de la neuroanatomía del perro. No obstante, la cantidad y calidad de información respecto al encéfalo de los caninos que ha generado este impulso en la neurofisiología y la neurología experimental, no ha encontrado su contraparte en la neuroanatomía, situación que genera una disociación del conocimiento, al punto de trabajar con distintas nomenclaturas y denominaciones. En este trabajo se ha intentado, con un criterio fundamentalmente anatómico, conjugar las descripciones macroscópicas del cerebro de los caninos con las descripciones citoarquitectónicas, así como también, con los hallazgos funcionales, para que la neuroanatomía sea la base de la pirámide del conocimiento en el que se sustenta la neurofisiología y la neurología aplicada

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The morphology of the parotid and submandibular glands in the marten, a carnivore, were studied and analyzed under a transmission electron microscope. The nature of the granules in both glands, as well as in the acini and in the secretory tubules, is rather mucous. The structure of the secretory tubules is very characteristic, especially the striated ones. The myoepithelial cells are close to the acini and tubules and covered by the basement membrane separating them from the connective tissue, which enhances its epithelial origin. The cytoplasm of the basal parts of the acinar and tubular cells is abundant and separates the nucleus from the secretion granules. Although the morphology of the salivary glands of many carnivores is known, those of the parotid gland of the marten present peculiar characteristics, since they produce a rather mucous saliva and the granules, when forming, are far from the base as well as from the apex of the secretory cells. The submandibular gland contains granules of different densities, an aspect that in general resembles that of other animals.

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This study describes a strong aponeurosis on the caudal surface of the antebrachium, between the Mm. Flexoris and the M. pronator quadratus. This aponeurosis has not been experimentally validated. By dissection and macroscopic examination of formaldehyde-prepared material, and experimental surgical transection of the structure in F. catus, the aponeurosis is described and its functional capacity is determined. The origin of the aponeurosis is the Facies caudalis, Margo medialis of the Radius and distal Ulna and inserts on the Crista transversa of the Radius and the Ligg. radiocarpeum palmare and ulno-carpeum palmare, and a strong Pars radialis. Its disposition is similar to that of the supernumerary M. anterior radialis brevis in humans. Surgical transection of the aponeurosis in F. catus resulted in hyperextension of the Manus and a decrease in the Carpus in its weight-bearing ability. These findings indicate the anatomico-functional importance of the aponeurosis in providing support to the claws.

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Despite numerous systematic studies, the relationships among many species within the dog family, Canidae, remain unresolved. Two problems of broad evolutionary significance are the origins of the taxonomically rich canidae fauna of South America and the development in three species of the trenchant heel, a unique meat-cutting blade on the lower first molar. The first problem is of interest because the fossil record provides little evidence for the origins of divergent South American species such as the maned wolf and the bush dog. The second issue is problematic because the trenchant heel, although complex in form, may have evolved independently to assist in the processing of meat. We attempted to resolve these two issues and five other specific taxonomic controversies by phylogenetic analysis of 2,001 base pairs of mitochondrial DNA (mtDNA) sequence data from 23 canidae species. The mtDNA tree topology, coupled with data from the fossil record, and estimates of rates of DNA sequence divergence suggest at least three and possibly four North American invasions of South America. This result implies that an important chapter in the evolution of modern canids remains to be discovered in the fossil record and that the South American canidae endemism is as much the result of extinction outside of South America as it is due to speciation within South America. The origin of the trenchant heel is not well resolved by our data, although the maximum parsimony tree is weakly consistent with a single origin followed by multiple losses of the character in several extant species. A combined analysis of the mtDNA data and published morphological data provides unexpected support for a monophyletic South American canidae clade. However, the homogeneity partition tests indicate significant heterogeneity between the two data sets.

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Two endocasts of the extinct marsupial Thylacosmilus atrox are studied. The specimens were found in outcrops at present considered of Pliocene Age. The followings are the conclusions arrived in the study: 1) The encephalon of Thylacosmilus atrox shows a well developed neocortex, with a deep rhinal fissure and the major marsupial neocortical sulci well observable. The homologies of the sulci was certainly easy in the major part of them, and consequently, functional inferencies were possible. 2) The somatic neocortical area shows certain distinctive characteristics. It appears that the size proportions between the mandibular and maxillary areas is reversed in T. atrox, which appears congruent with the infered function of its peculiar cranial anatomy. 3) The relative brain size of T. atrox is very heigh for a Polyprotodont marsupial being its encephalization quotients and progression indexes at the level of the living Diprotodonta. 4) Thylacosmilus atrox was a very peculiar extinct carnivore marsupial, which at the Late Tertiary in South America reached higher levels of encephalization than the posterior or living representatives of its same Order.

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