Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Systematization of the brain base arteries in nutria (Myocastor coypus) / Sistematização das artérias da base do encéfalo em nutria (Myocastor coypus)

Background: The nutria (Myocastor coypus) is a medium-size, semi-aquatic rodent, valued in skin and meat industry. The brain circulation has been well studied in rodents but not in nutria. To understand and compare the phylogenetic development of the arteries of the base of the brain in rodents, this paper aims to describe and systematize these arteries, establishing a standard model and its main variations in nutria.Materials, Methods & Results: Following approval by the Ethics Committee of Federal University of Rio Grande do Sul, thirty nutrias from a commercial establishment authorized by Brazilian Institute of Environment and Natural Resources (IBAMA) were studied. For euthanasia, was applied heparin (10000 U.I for animal), intraperitoneally, and after thirty minutes the animals ware sedated with acepromazine (0.5 mg/kg) and meperidine (20 mg/kg), intramuscularly. After sedation, they were euthanized with thiopental sodium (120 mg/kg) and lidocaine (10 mg/mL), intraperitoneally. The heart was accessed, the cardiac apex was sectioned, the aorta was cannulated via the left ventricle and clamped close to the diaphragm, and the arterial system was washed with saline solution and filled with latex. The animals were submerged in water for latex polymerization, the trunk was sectioned, the skin removed and a bony window was opened in the skull vault. The pieces were fixed in formaldehyde. The brains were removed, and schematic drawings of the arteries from the base of the brain were made for elaboration of the results. The nutria’s brain was vascularized by the vertebro-basilar system. The terminal branches of the right and left vertebral artery were anastomosed on the ventral surface of the medulla oblongata, forming the basilar artery, and caudally the ventral spinal artery.[...]

Systematization of the brain base arteries in nutria (Myocastor coypus) / Sistematização das artérias da base do encéfalo em nutria (Myocastor coypus)

Background: The nutria (Myocastor coypus) is a medium-size, semi-aquatic rodent, valued in skin and meat industry. The brain circulation has been well studied in rodents but not in nutria. To understand and compare the phylogenetic development of the arteries of the base of the brain in rodents, this paper aims to describe and systematize these arteries, establishing a standard model and its main variations in nutria.Materials, Methods & Results: Following approval by the Ethics Committee of Federal University of Rio Grande do Sul, thirty nutrias from a commercial establishment authorized by Brazilian Institute of Environment and Natural Resources (IBAMA) were studied. For euthanasia, was applied heparin (10000 U.I for animal), intraperitoneally, and after thirty minutes the animals ware sedated with acepromazine (0.5 mg/kg) and meperidine (20 mg/kg), intramuscularly. After sedation, they were euthanized with thiopental sodium (120 mg/kg) and lidocaine (10 mg/mL), intraperitoneally. The heart was accessed, the cardiac apex was sectioned, the aorta was cannulated via the left ventricle and clamped close to the diaphragm, and the arterial system was washed with saline solution and filled with latex. The animals were submerged in water for latex polymerization, the trunk was sectioned, the skin removed and a bony window was opened in the skull vault. The pieces were fixed in formaldehyde. The brains were removed, and schematic drawings of the arteries from the base of the brain were made for elaboration of the results. The nutrias brain was vascularized by the vertebro-basilar system. The terminal branches of the right and left vertebral artery were anastomosed on the ventral surface of the medulla oblongata, forming the basilar artery, and caudally the ventral spinal artery.[...](AU)

Ectoparasites from some Myocastor coypus (Molina, 1782) populations (Coypus or Nutria) in Argentina / Ectoparasitas de algumas populações de Myocastor coypus (Molina, 1782) (Coypus ou Nutria) na Argentina

The occurrence of ectoparasites in wild nutria is poorly understood. Fifty-five livetrapped wild nutria (Myocastor coypus) from its indigenous region were examined for ectoparasites after capture from December 2013 to December 2014. The captures came from the Buenos Aires Province, by far the area of the country most densely populated by nutria, characterized as a temperate grassland, which are prime areas for sustained agriculture. Only one species of chewing lice (Pitrufquenia coypus, Marelli, 1932), one flea (Nosopsyllus fasciatus, Bosc, 1800) and one tick (Rhipicephalus sanguineus, Latreille, 1806) were collected. Fourteen percent of the animals were infested and P.coypus, an obligate parasite of the nutria, which was the most prevalent ectoparasite. N. fasciatus and R. sanguineus occurrence remains controversial as they may or may not be some accidental host species. To our knowledge, this is the first comprehensive and systematic survey of ectoparasites in wild nutria from the southern hemisphere, the indigenous region of this species.(AU)

A ocorrência de ectoparasitas em nutria selvagem é pouco compreendido. Cinquenta e cinco nutria selvagem capturadas (Myocastor coypus) de sua região indígena foram examinados para os ectoparasitas após até captura a partir de dezembro de 2013 a dezembro de 2014. As capturas ocorreram no estado de Buenos Aires, a área mais densamente povoada do país por nutria, caraterizada como uma pastagem temperada, que se tornou área principal para a agricultura sustentável. Uma espécie de piolhos de mastigação (Pitrufquenia coypus, Marelli, 1932), uma pulga (Nosopsyllus fasciatus, Bosc, 1800) e um carrapato (Rhipicephalus sanguineus, Latreille, 1806) foram recolhidos. Catorze por cento dos animais foram infestadas pelo P.coypus, um parasita obrigatório do nutria, sendo o ectoparasita mais prevalente. A ocorrência de N. fasciatus e R. sanguineus continua controversa, pois podem ou não ser algumas espécies hospedeiras acidentais. Para nosso conhecimento, este é o primeiro estudo abrangente e sistemático de ectoparasitas em nutria selvagem do hemisfério sul, a região indígena desta espécie.(AU)

Descenso testicular: revisão de literatura / Descent testicular: literature review

Durante a fase embrionária o testículo migra para a cavidade abdominal isso se chama descenso testicular. A descida do testículo para o interior do escroto é necessária na maioria dos mamíferos. Este processo depende do gubernáculo testicular, que orienta o testículo em direção ao canal inguinal e através dele. O aumento do peso do testículo, a pressão intraabdominal e a abertura do anel inguinal fornecem a passagem desse órgão para o interior do canal inguinal e, com o total encurtamento do gubernáculo o testículo se posiciona definitivamente no interior do escroto. Vários outros fatores auxiliam na espermatogenese bem como dentre eles a pele glabra do escroto e com presença de glândulas sudeoríferase sebáceas, internamente ao escroto uma túnica dartus, músculo cremáster e plexo pampiniforme. (AU)

During infancy the testicle migrates into the abdominal cavity it is called testicular descent. The descent of the testis into the scrotum is required in most mammals. This process depends on the testicular gubernaculum , which guides the testicle into the inguinal canal and through it. The increase in testis weight , intra-abdominal pressure and the opening of the inguinal ring that body provide passage into the inguinal canal , and with the total shortening of the testis gubernaculum be finally positioned within the scrotum. Several other factors aid in spermatogenesis and among them the glabrous skin of the scrotum and the presence of sudeoríferase sebaceous glands inside the scrotum one dartus tunic , cremaster muscle and […] (AU)

Descenso testicular: revisão de literatura / Descent testicular: literature review

Durante a fase embrionária o testículo migra para a cavidade abdominal isso se chama descenso testicular. A descida do testículo para o interior do escroto é necessária na maioria dos mamíferos. Este processo depende do gubernáculo testicular, que orienta o testículo em direção ao canal inguinal e através dele. O aumento do peso do testículo, a pressão intraabdominal e a abertura do anel inguinal fornecem a passagem desse órgão para o interior do canal inguinal e, com o total encurtamento do gubernáculo o testículo se posiciona definitivamente no interior do escroto. Vários outros fatores auxiliam na espermatogenese bem como dentre eles a pele glabra do escroto e com presença de glândulas sudeoríferase sebáceas, internamente ao escroto uma túnica dartus, músculo cremáster e plexo pampiniforme.

During infancy the testicle migrates into the abdominal cavity it is called testicular descent. The descent of the testis into the scrotum is required in most mammals. This process depends on the testicular gubernaculum , which guides the testicle into the inguinal canal and through it. The increase in testis weight , intra-abdominal pressure and the opening of the inguinal ring that body provide passage into the inguinal canal , and with the total shortening of the testis gubernaculum be finally positioned within the scrotum. Several other factors aid in spermatogenesis and among them the glabrous skin of the scrotum and the presence of sudeoríferase sebaceous glands inside the scrotum one dartus tunic , cremaster muscle and […]

Eliminação dos riscos de transmissão da Febre Maculosa Brasileira através do manejo de capivaras (Hydrochoerus hydrochaeris) em uma área de transmissão no município de Itu-SP

A bactéria Rickettsia rickettsii é o agente etiológico da Febre Maculosa Brasileira (FMB), que tem ocorrido em torno de 80% de letalidade no sudeste do Brasil. A maioria dos casos de FMB no sudeste do Brasil tem sido associada à transmissão por Amblyomma sculptum em áreas onde esta espécie de carrapato foi mantida principalmente por capivaras (Hydrochoerus hydrochaeris). Neste trabalho, avaliamos a expansão de uma população de capivaras em um condomínio residencial no Estado de São Paulo e as implicações dessa expansão para a ocorrência de carrapatos e FMB. Para esse fim, quantificações do número de capivaras foram feitas visualmente de 2004 a 2013. Em 2012, houve um caso humano da FMB na área, o que motivou uma intervenção oficial que consiste no cercamento do perímetro do residencial e na eutanásia de toda a população de capivaras entre 2012 e 2015. Posteriormente, as contagens de capivara durante 2016-2018 confirmaram a ausência de capivaras na área. A contagem de carrapatos no ambiente foi realizada por armadilhas de gelo seco (CO2) de 2005 a 2018, e os resultados são apresentados como número médio de carrapatos por armadilha. Durante 2017-2018, realizamos a captura de ratão do banhado (Myocastor coypus) nas áreas anteriormente ocupadas pelas capivaras. Finalmente, cães domésticos em 2006 e 2011, capivaras em 2012 e ratões do banhado em 2017-2018 foram testados sorologicamente para a presença de. anticorpos de anti-R. rickettsii. Os resultados mostram que o número de capivaras aumentou 5 vezes durante num período de 8 anos, de 2004 (quando 41 capivaras foram contadas) para 2012, quando 230 capivaras foram contadas e o programa de remoção foi iniciado devido a um caso de FMB naquele mesmo ano. Nenhuma capivara foi observada no condomínio durante as contagens de 2016 a 2018. As armadilhas de gelo seco coletaram duas espécies de carrapatos: A. sculptum e Amblyomma dubitatum. O número de carrapatos adultos de A. dubitatum foram geralmente mais altos do que os adultos de A. sculptum durante 2005-2006; no entanto, durante 20122013, A. sculptum superou em número A. dubitatum por uma grande diferença. Durante 2016-2018 (após a remoção de capivaras), o número de ambas as espécies foi sempre muito baixo e estatisticamente semelhante. Considerando cada espécie separadamente, os números de A. dubitatum foram relativamente constantes durante 20052013. Em contraste, os números de A. sculptum mostraram um aumento significativo de 2005-2006 para 2012. Comparando o número de carrapatos adultos por armadilha com o número de capivaras no condomínio, o baixo número de adultos de A. sculptum durante 2005 -2006 coincidiu com números relativamente baixos de capivaras (<80). Por outro lado, em 2012 foram contabilizados os maiores números de carrapatos e capivaras de A. sculptum (230 animais). Apenas quatro ratões do banhado foram capturados durante 2017-2018, infestadas por 0 a 5 ninfas de A. dubitatum. Todas as amostras de sangue caninos de 2006 (30 cães) e 2011 (10 cães) foram soronegativas para R. rickettsii, assim como as quatro ratões do banhado de 2017 - 2018. De um total de 172 capivaras testadas em 2012-2013, 83 (48,3%) foram sororeativos para R. rickettsii. Nossos resultados indicam que o surgimento do FMB no condomínio foi conseqüência do aumento da população de capivaras na área, que por sua vez, proporcionou o incremento da população de A. sculptum. A eutanásia de toda a população de capivaras condomínio resultou na supressão local ambiental da quantidade de A. sculptum e A. dubitatum, eliminando os riscos de novos casos de FMB entre moradores do condomínio.

The bacterium Rickettsia rickettsii is the etiological agent of Brazilian spotted fever (BSF), which has occurred around 80% fatality rates in southeastern Brazil. Most of the BSF cases in southeastern Brazil have been associated with the transmission by Amblyomma sculptum in areas where this tick species has been maintained chiefly by capybaras (Hydrochoerus hydrochaeris). Herein, we evaluated the expansion of a capybara population in a residential park in the state of São Paulo, and the implications of such expansion to occurrence of ticks and BSF. For this purpose, quantifications of the number of capybaras were done visually from 2004 to 2013. In 2012, there was a BSF human case in the area, what motivated an official intervention consisting of the compete fencing of the residential park and the culling of the entire capybara population from 2012 and 2015. Thereafter, capybara countings during 2016-2018 confirmed the absence of capybaras in the residential park. Quantification of ticks in the environment was performed by dry ice (CO2) traps from 2005 to 2018, and the results are presented as mean number of ticks per trap. During 2017-2018, we performed capture of nutrias (Myocastor coypus) in the areas previously occupied by capybaras. Finally, domestic dogs in 2006 and 2011, capybaras in 2012, and nutrias in 2017-2018 were serologically tested for the presence of anti-R. rickettsii antibodies. Our results show that capybara number increased 5 times during an 8-year period, from 2004 (when 41 capybaras were counted) to 2012, when 230 capybaras were counted and the culling program was initiated because of a BSF case in that same year. No capybara was seen in the residential Park during the countings of 2016 - 2018. Dry ice traps collected two tick species: A. sculptum and Amblyomma dubitatum. The number of A. dubitatum adult ticks were generally higher than A. sculptum adults during 20052006; however, during 20122013, A. sculptum outnumbered A. dubitatum by a large difference. During 2016-2018 (after capybara culling), the number of both species were always very low and statistically similar. Considering each species separately, the numbers of A. dubitatum were relatively constant during 20052013. In contrast, the numbers of A. sculptum showed a marked increase from the 20052006 to 2012. Comparing the number of adult ticks per trap with the number of capybaras in the residential park, the low numbers of A. sculptum adult ticks during 2005-2006 coincided with relatively low capybara numbers (< 80). On the other hand, in 2012 we counted the highest numbers of both A. sculptum ticks and capybaras (230 animals). Only four nutrias were trapped during 20172018, which were infested by 0 to 5 nymphs of A. dubitatum. All canine blood samples from 2006 (30 dogs) and 2011 (10 dog) were seronegative to R. rickettsii, as were the four nutrias from 2017 2018. From a total of 172 capybaras tested in 2012-2013, 83 (48.3%) were seroreactive to R. rickettsii. Our results indicate that the emergence of BSF in the residential park was a consequence of the increase of the capybara population in the area, which in turn, provided the increment of the A. sculptum population. Culling the entire capybara population of the residential park resulted in the local suppression of the environmental burdens of A. sculptum and A. dubitatum,eliminating the risks of new BSF cases among residents of the residential park.

Arterial vascularization of the stomach, duodenum, pancreas, liver and spleen in Myocastor coypus (nutria) / Vascularização arterial do estômago, duodeno, pâncreas, fígado e baço em Myocastor coypus (nutria)

Background: Rodents are the largest group of mammals. The nutria is a middle-sized rodent, native to South America, raised for meet and fur. This study has the objective to systematize and describe the arterial vascularization of the stomach, duodenum, pancreas, liver and spleen of nutria (Myocastor coypus). Materials, Methods & Results: Thirty young and adult nutrias (15 females and 15 males) were used. Animals were administered 5000 IU heparin and after 30 min 20 mL of 12.5% sodium thiopental by intraperitoneal injection. Then, the thoracic cavity was ventrally opened, the thoracic aorta cannulated close to the diaphragm and the system was washed with saline solution. After, the system was filled with 603 latex colored in red and pieces were immersed in 20% formol for fixation for seven days. The abdominal cavity opened at the ventral median line, the branches of the abdominal aorta artery were dissected and, after the section of the main arterial trunks (celiac, caudal and cranial mesenteric arteries), the digestive tract was removed, sectioning the esophagus and rectus. Schematic drawings of all pieces were prepared with the use of a magnifying glass. The stomach, duodenum, pancreas, liver and spleen of the nutrias were exclusively irrigated by branches of the celiac and the cranial mesenteric arteries, visceral collateral first and second branches of the abdominal aort

Os roedores (ordem Rodentia) representam o mais numeroso grupo dentro da classe Mammalia. No Brasil, da família Capromyidae, registra-se a ocorrência apenas do gênero Myocastor, com uma única espécie vivente, o Myocastor coypus, conhecido como ratão do banhado, ou nutria. [...]

Vascularização arterial do estômago, duodeno, pâncreas, fígado e baço em Myocastor coypus (nutria) / Arterial Vascularization of the Stomach, Duodenum, Pancreas, Liver and Spleen in Myocastor coypus (nutria)

Background: Rodents are the largest group of mammals. The nutria is a middle-sized rodent, native to South America, raised for meet and fur. This study has the objective to systematize and describe the arterial vascularization of the stomach, duodenum, pancreas, liver and spleen of nutria (Myocastor coypus). Materials, Methods & Results: Thirty young and adult nutrias (15 females and 15 males) were used. Animals were administered 5000 IU heparin and after 30 min 20 mL of 12.5% sodium thiopental by intraperitoneal injection. Then, the thoracic cavity was ventrally opened, the thoracic aorta cannulated close to the diaphragm and the system was washed with saline solution. After, the system was filled with 603 latex colored in red and pieces were immersed in 20% formol for fixation for seven days. The abdominal cavity opened at the ventral median line, the branches of the abdominal aorta artery were dissected and, after the section of the main arterial trunks (celiac, caudal and cranial mesenteric arteries), the digestive tract was removed, sectioning the esophagus and rectus. Schematic drawings of all pieces were prepared with the use of a magnifying glass. The stomach, duodenum, pancreas, liver and spleen of the nutrias were exclusively irrigated by branches of the celiac and the cranial mesenteric arteries, visceral collateral first and second branches of the abdominal aorta, respectively. The celiac artery presented a trifurcation after a short path, which originated the left gastric, the lienal and the hepatic arteries in 83.3% of the pieces. But in 16.7% of the cases, the celiac artery emitted the left gastric and lineal arteries, with the hepatic artery being a collateral branch of the cranial mesenteric artery. The lienal artery in 96.7% of the cases, projected lateralwards and emitted, after a short trunk, the left gastroeiploic artery, then continued until the spleen as lineal artery. The caudal pancreaticoduodenal artery was a right branch of the cranial mesenteric artery in 96.7% of the cases, and in 3.3% was branch of the hepatic artery, originated from the cranial mesenteric artery. Discussion: In nutria, it was observed that the celiac artery was originated from the ventral surface of the abdominal aorta, immediately caudal to the aortic hiatus. It was also observed the formation of a common trunk between the celiac and the cranial mesenteric arteries, what was not found in the studied species or in the White-lipped peccary. In nutria, the celiac artery originated, more frequently, the left gastric, lineal and hepatic arteries, with the same trifurcation observed in the White-lipped peccary. Also, in the nutria, the left gastric artery went towards the small curvature of the stomach and emitted a cardiac branch before reaching it and from this branch also emitted some esophagic branches and a large number of branches distributed on the visceral and parietal surfaces of the stomach. In the nutria, the left gastric artery also emitted a similar vessel, which dorsally countered the esophagus to the left and distributed to the left sac of the stomach, besides some ramifications to the esophagus. In the rabbit, as well as in the nutria, the lineal artery presented a similar trajectory and ramification, but in none of the samples it was observed that this artery or the left gastroepiploic artery reached the pyloric region. In the White-lipped peccary, the hepatic artery was emitted in a common trunk with the splenic or left gastric arteries, what was not observed in any of the pieces in nutria. The stomach, duodenum, pancreas, liver and spleen of the nutria are vascularized by branches emitted from the celiac and cranial mesenteric arteries.

Distribution of cranial and caudal mesenteric arteries in nutria (Myocastor coypus) / Distribuição das artérias mesentéricas cranial e caudal na nutria (Myocastor coypus)

Background: The nutria (Myocastor coypus) is a semi-aquatic rodent, originating from the extreme south of South America, exploited for commercial purposes, in particular the quality of your skin and flesh. The objective of this study was to systematize and describe the cranial and caudal mesenteric arteries in the nutria. Materials, Methods & Results: To perform this study were used a total of 30 specimens of nutria, 15 females and 15 males. To the animals were administered heparin and after thirty minutes Thiopental Sodium, via an intraperitoneal injection, to perform euthanasia. The thoracic cavity was opened ventrally in plastron, the thoracic aorta was cannulated and the system was washed with saline solution. Then the system was filled with latex 603 colored in red and the animals remained immersed in running water for one hour. The skin was removed and then the trunk was transversally sectioned near the last thoracic vertebrae. The abdominal cavity remained closed and formaldehyde was administered via an intraperitoneal injection. The specimens were fixed in formaldehyde for seven days, the abdominal cavity was opened, the viscera were removed in block and the arteries were dissected. Statistical analyses of the results were performed using percentage values. It was observed that the abdominal aorta gave rise to the cranial and caudal mesenteric arteries. The cranial

A nutria (Myocastor coypus) é um roedor semi-aquático de porte médio, originário do extremo sul da América do Sul, mas disseminado em várias partes do mundo, como Estados Unidos e Europa, onde tem sido explorado com fins comerciais, em especial pela qualidade de sua pele e de sua carne. Alimentam-se de capim, raízes e plantas aquáticas. [...]

Distribuição das artérias mesentéricas cranial e caudal na nutria (Myocastor coypus) / Distribution of Cranial and Caudal Mesenteric Arteries in Nutria (Myocastor coypus)

Background: The nutria (Myocastor coypus) is a semi-aquatic rodent, originating from the extreme south of South America, exploited for commercial purposes, in particular the quality of your skin and flesh. The objective of this study was to systematize and describe the cranial and caudal mesenteric arteries in the nutria. Materials, Methods & Results: To perform this study were used a total of 30 specimens of nutria, 15 females and 15 males. To the animals were administered heparin and after thirty minutes Thiopental Sodium, via an intraperitoneal injection, to perform euthanasia. The thoracic cavity was opened ventrally in plastron, the thoracic aorta was cannulated and the system was washed with saline solution. Then the system was filled with latex 603 colored in red and the animals remained immersed in running water for one hour. The skin was removed and then the trunk was transversally sectioned near the last thoracic vertebrae. The abdominal cavity remained closed and formaldehyde was administered via an intraperitoneal injection. The specimens were fixed in formaldehyde for seven days, the abdominal cavity was opened, the viscera were removed in block and the arteries were dissected. Statistical analyses of the results were performed using percentage values. It was observed that the abdominal aorta gave rise to the cranial and caudal mesenteric arteries. The cranial mesenteric artery originated as a standard the caudal pancreaticoduodenal, middle colic, right colic, ileocolic, jejunal arteries and ileal branches. The pancreaticoduodenal artery traveled the interior of mesoduodeno irrigating part of the body and the right lobe of the pancreas and the end of the duodenum. The middle colic artery bifurcated into right and left branches, going to irrigate the transverse and descending colon, respectively. The right colic artery gave a branch to the beginning of the ascending colon, small branches to the transverse colon and continued going through the loop formed by the ascending colon. The ileocolic artery emitted the cecal artery, ileal, ascending colic and cecum branches, for irrigation of the cecum, ileum and ascending colon. The jejunal arteries were responsible for the irrigation of the jejunum, ileum, and the last jejunal artery anastomosed with the ileal artery. The caudal mesenteric artery originated the left colic and cranial rectal arteries. Discussion: In this study and in others papers of nutria and chinchilla, we observed the cranial mesenteric artery originating from the abdominal aorta caudally to the celiac artery. The sequences of the origin of the branches of the cranial mesenteric artery were varied between rodent species and within them. In this study, and in another one of nutria, the caudal pancreaticoduodenal artery was predominantly double. In rodents, the middle colic artery was originated, as standard, from the cranial mesenteric artery, but this study showed that in one piece, this artery originated from the ileocolic artery. The terminal branch of middle colic artery was anastomosed in osculum with the left colic artery, branch of the caudal mesenteric artery in 46,7% of the sample, and this observation was also found in another articles of nutria (30%) and agouti (36,3%). The right colic artery emitted a colic branch to the top of the ascending colon and anastomosed in osculum to the colic branch of the ileocolic artery in 46.7% of the animals, and this anastomosis was also observed in agouti. The number of jejunal arteries varied widely inside and within species of rodents. The ileocolic artery vascularized the cecum, ileum and ascending colon in nutrias and agouti. The caudal mesenteric artery bifurcated into the left colic and cranial rectal artery in nutrias, agoutis, chinchillas, cavies and rabbits.

SISTEMATIZAÇÃO, DISTRIBUIÇÃO E TERRITÓRIOS DAS ARTÉRIAS CEREBRAIS ROSTRAL, MÉDIA E CAUDAL NA SUPERFÍCIE DO ENCÉFALO EM NUTRIA (Myocastor coypus)

Foram utilizados 30 encéfalos de nutria (Myocastor coypus), injetados com látex, corado em vermelho, com objetivo de sistematizar e descrever a distribuição e territórios das artérias cerebrais rostral, média e caudal e suas ramificações na superfície dos hemisférios cerebrais e no tronco encefálico. A artéria carótida interna apresentouse atrofiada, sendo o encéfalo vascularizado exclusivamente pelo sistema vértebrobasilar. A artéria vertebral penetrou pelo forame magno, e seus antímeros anastomosaram-se formando uma calibrosa artéria basilar. A artéria basilar, de grande calibre, alcançou o sulco rostral da ponte, dividiu-se em dois ramos terminais, em uma divergência de aproximadamente 90°, e lançou as artérias cerebelar rostral, cerebral caudal, hipofisária, corióidea rostral e ramos centrais para o lobo piriforme. Após, os ramos terminais da artéria basilar projetaram-se rostro-lateralmente até a altura da origem aparente do nervo oculomotor (III par craniano), e curvaram-se alcançando o trato óptico, lançando a artéria cerebral média e a artéria cerebral rostral, seu ramo terminal. A artéria cerebelar rostralemitiu um ramo tectal mesencefálico caudal, para a face caudal do colículo caudal. A artéria cerebral caudal, normalmente única, de grosso calibre, projetava-se látero-dorsalmente para o interior da fissura transversa do cérebro, lançando as artérias tectal mesencefálica rostral (componente proximal) e interhemisférica caudal. A artéria tectal mesencefálica rostral vascularizou a maior parte do tecto mesencefálico, e os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formaram uma rede anastomótica sobre a superfície dos colículos rostrais e caudais. A artéria inter-hemisférica caudal lançou ramos centrais, artérias corióidea caudal (esta anastomosava-se com a artéria corióidea rostral, vascularizando o diencéfalo e o hipocampo), hemisféricas occipitais (para o pólo occipital do hemisfério cerebral), ramos tectais mesencefálicos rostrais (componentes distais), e então contornava o esplênio do corpo caloso anastomosando-se em ósculo com a artéria inter-hemisférica rostral. A artéria cerebral média, de grande calibre, projetava-se pelo interior da fossa lateral do cérebro, lançando ramos centrais caudais e rostrais para o páleo-palio da região. Ela ultrapassou o sulco rinal lateral, formando um a dois eixos principais para a face convexa do hemisfério cerebral, originando ramos hemisféricos convexos caudais e rostrais, e suas ramificações terminais anastomosavam-se em ósculo no lobo parietal com os ramos das artérias hemisféricas mediais rostrais, ramo da artéria cerebral rostral. A artéria cerebral rostral, de grosso calibre, projetou-se rostro-medialmente, na altura do quiasma óptico, emitindo um ramo medial, para a fissura longitudinal do cérebro. Seu eixo principal projetava-se rostralmente, acompanhando a fissura longitudinal do cérebro, até o bulbo olfatório, continuando-se para a cavidade nasal como artéria etmoidal interna. Esta emitiu ramos centrais, hemisférico medial e artérias lateral e medial do bulbo olfatório. O ramo medial anastomosava-se com seu homólogo contralateral, quando presente, fechando o círculo arterial cerebral rostralmente, formando uma artéria comunicante rostral, mediana ímpar. Esta se bifurcou nas artérias inter-hemisféricas rostrais, que vascularizavam toda face medial dos hemisférios cerebrais, até o esplênio do corpo caloso, emitindo as artérias hemisférica rostral e hemisférica medial rostral, sendo que os ramos terminais desta alcançavam a face convexa, anastomosando-se com os ramos terminais da artéria cerebral média.

Thirty nutria brains were used (Myocastor coypus), injected with latex and stained in red, in order to systematize and describe the distribution and the territories of the rostral, middle and caudal cerebral arteries and their ramifications in the surface of cerebral hemispheres and in the brain stem in nutria. The internal carotid artery was atrophied, being the encephalic vascularized exclusively by the vertebro-basilar system. The vertebral artery penetrated the magnum foramen, and their antimeres anastomosed to form a calibrous basilar artery. The basilar artery, of great caliber, reached the rostral sulcus of the pons, divided into two terminal branches, at a divergence of approximately 90°, and launched the rostral cerebellar, caudal cerebral, hypophyseal, rostral choroid arteries and central branches to the piriform lobe. Afterwards, the terminal branches of the basilar artery were projected rostrolaterally up to the apparent origin of the oculomotor nerve (III cranial nerve), and bent over reaching the optic tract, launching the middle cerebral artery and the rostral cerebral artery, its terminal branch. The rostral cerebellar artery emitted a caudal tectal mesencephalic branch, to the caudal surface of the caudal colliculus. The caudal cerebral artery, usually unique, of large caliber, projected laterally into the transverse fissure of the brain, launching the rostral tectal mesencephalic (proximal component) and caudal inter-hemispheric arteries. The rostral tectal mesencephalic artery vascularized most of the mesencephalic roof, and the terminal branches of the tectal mesencephalic arteries, rostral and caudal, formed an anastomotic network on the surface of rostral and caudal colliculus. The caudal inter-hemispheric artery emitted central branches, caudal choroid (this anastomosis with the rostral choroidal artery, vascularizing of the diencephalon and hippocampus), occipital hemispheres artery (to the occipital pole of the cerebral hemisphere), rostrais tectral mesencephalic branches (distal components), and then bypassed the splenius of the corpus callosum anastomosing "in osculum" with the rostral inter-hemispheric artery. The medium cerebral artery, of great caliber, projected through the interior of the cerebral lateral fossa, Releasing caudal and rostrais central branches to the paleopallio region. It crossed the lateral rinal groove, forming one to two main axes to the convex surface of the cerebral hemisphere, originating caudal and rostral convex hemispheric branches, and its terminal branches anastomosed "in osculum" in the parietal lobe with the branches of the mediais rostrais hemispherics arteries, branch of the rostral cerebral artery. The rostral cerebral artery, of large caliber, projected rostro-medially, at the level of optic chiasm, emitting a medial branch, for the cerebral longitudinal fissure. Its main axis was projected rostrally, accompanying the cerebral longitudinal fissure, until the olfactory bulb, continuing to the nasal cavity as internal ethmoidal artery. It emitted central branches, medial hemispheric and lateral and medial of the olfactory bulb arteries. The medial branch was anastomosed with its contralateral homologous, when present, closing the cerebral arterial circle rostrally, forming a rostral communicating artery, unique median. This bifurcated in the inter-hemispheric rostrais arteries, which vascularized the entire medial face of the cerebral hemispheres, until the splenius of the corpus callosum, emitting the rostral hemispherical and hemispherical medial rostral arteries, being that the terminal branches of this reached the convex surface, anastomosing with the terminal branches of the middle cerebral artery.

Ramos colaterais viscerais da artéria aorta abdominal em Myocastor coypus (nutria)

A nutria é um roedor originário do extremo sul da América do Sul explorado comercialmente por sua pele e carne. Neste trabalho, sistematizou-se os ramos colaterais viscerais da aorta abdominal. Utilizaram-se 30 nutrias, 15 fêmeas e 15 machos, com o sistema arterial aórtico-abdominal preenchido com látex 603. A aorta abdominal emitiu ventralmente como ramo colateral visceral à artéria celíaca, que se trifurcou nas artérias gástrica esquerda, hepática e lienal. Os ramos da artéria celíaca promoveram a irrigação do estômago, duodeno, fígado, pâncreas e baço. A seguir, a aorta abdominal emitiu a artéria mesentérica cranial, de calibre maior que a artéria celíaca, justaposta caudalmente. A artéria mesentérica cranial emitiu ramos, vascularizando a parte final do duodeno, lobo direito do pâncreas, jejuno, íleo, ceco, cólon maior e cólon menor. A aorta abdominal emitiu lateralmente as artérias renais direita e esquerda. As artérias adrenais foram ramos colaterais diretos das artérias renais e/ou da artéria frênico-abdominal. A artéria mesentérica caudal foi emitida da superfície ventral da aorta abdominal, próximo à sua bifurcação em artérias ilíacas comuns. A artéria mesentérica caudal lançou ramos para o cólon menor e porção cranial do reto. Os ramos colaterais viscerais diretos da aorta abdominal foram: artéria celíaca, artéria mesentérica cranial, artérias renais e artéria mesenté

Ramos colaterais parietais e terminais da aorta abdominal em Myocastor coypus (nutria) / Terminal and parietal colateral branches of the abdominal aorta in Myocastor coypus (nutria)

Neste estudo, utilizaram-se 30 nutrias, 15 fêmeas e 15 machos, com o sistema arterial aórtico-abdominal preenchido com látex 603, pigmentado em vermelho, e fixado em uma solução aquosa de formaldeído a 20 por cento. A aorta abdominal emitiu de sua superfície dorsal de 6 a 8 artérias lombares únicas. Das artérias renais, direita e esquerda, originaram-se as artérias frênico-abdominal para irrigar parte do diafragma e da parede abdominal lateral cranial. A aorta abdominal lançou dorsalmente, a artéria sacral mediana, cranialmente a sua bifurcação em artérias ilíacas comuns. As artérias ilíacas comuns, ramos terminais da aorta abdominal, originaram as artérias ilíacas interna e externa. A artéria ilíaca interna distribuiu-se nas vísceras da cavidade pélvica. A artéria ilíaca externa emitiu uma artéria umbilical e, antes de alcançar o anel femoral, lançou a artéria circunflexa ilíaca profunda para a parede abdominal lateral, em seus dois terços caudais. A artéria ilíaca externa lançou o tronco pudendo-epigástrico, que originou a artéria epigástrica caudal, para a parede abdominal ventral e a artéria pudenda externa, que saiu pelo canal inguinal, para irrigar a genitália externa. Os ramos parietais diretos da aorta abdominal foram as artérias lombares e a artéria sacral mediana, enquanto as artérias frênico-abdominal, circunflexa ilíaca profunda e epigástrica caudal, foram ramos colaterais parietais indiretos. Os ramos terminais da artéria aorta abdominal foram as artérias ilíacas comuns com seus ramos, as artérias ilíacas interna e externa.(AU)

For this study it was used 30 nutria, 15 females and 15 males, with its abdominal aorta system full filled with latex 603, stained in red, and fixed in an aqueous solution of formaldehyde 20 percent. The abdominal aorta emitted from its dorsal surface 6 to 8 single lumbar arteries. From the renal arteries, left and right, it has been originated the phrenicoabdominal arteries, in order to irrigate part of the diaphragm and the cranial lateral abdominal walls. The abdominal aorta emitted, dorsally, the median sacral artery, cranially to its bifurcation into the common iliac arteries. These common iliac arteries, terminal branches of the aorta, originate the internal and external iliac arteries. The internal iliac artery was distributed along the pelvic cavity viscera. The external iliac artery emitted an umbilical artery and, before reaching the inguinal ring, emitted the deep circunflex iliac artery to 2/3 of the caudal lateral abdominal wall. The external iliac artery emitted the pudendoepigastric trunk, wich has originated the caudal epigastric artery, to the ventral abdominal wall, and the external pudendal artery, wich passed through the inguinal ring to irrigate the external genital. The direct parietal branches of the abdominal aorta were the lumbar arteries and the median sacral artery, while the phrenicoabdominal arteries, deep circunflex iliac and the caudal epigastric artery were indirect colateral parietal branches. The terminal branches of the abdominal aorta were the common iliac arteries with its branches, the internal and external iliac arteries.(AU)

Arterial vascularization of the stomach, duodenum, pancreas, liver and spleen in Myocastor coypus (nutria) / Vascularização arterial do estômago, duodeno, pâncreas, fígado e baço em Myocastor coypus (nutria)

Background: Rodents are the largest group of mammals. The nutria is a middle-sized rodent, native to South America, raised for meet and fur. This study has the objective to systematize and describe the arterial vascularization of the stomach, duodenum, pancreas, liver and spleen of nutria (Myocastor coypus). Materials, Methods & Results: Thirty young and adult nutrias (15 females and 15 males) were used. Animals were administered 5000 IU heparin and after 30 min 20 mL of 12.5% sodium thiopental by intraperitoneal injection. Then, the thoracic cavity was ventrally opened, the thoracic aorta cannulated close to the diaphragm and the system was washed with saline solution. After, the system was filled with 603 latex colored in red and pieces were immersed in 20% formol for fixation for seven days. The abdominal cavity opened at the ventral median line, the branches of the abdominal aorta artery were dissected and, after the section of the main arterial trunks (celiac, caudal and cranial mesenteric arteries), the digestive tract was removed, sectioning the esophagus and rectus. Schematic drawings of all pieces were prepared with the use of a magnifying glass. The stomach, duodenum, pancreas, liver and spleen of the nutrias were exclusively irrigated by branches of the celiac and the cranial mesenteric arteries, visceral collateral first and second branches of the abdominal aort

Os roedores (ordem Rodentia) representam o mais numeroso grupo dentro da classe Mammalia. No Brasil, da família Capromyidae, registra-se a ocorrência apenas do gênero Myocastor, com uma única espécie vivente, o Myocastor coypus, conhecido como ratão do banhado, ou nutria. [...]

Ramos colaterais viscerais da artéria aorta abdominal em Myocastor coypus (nutria)

A nutria é um roedor originário do extremo sul da América do Sul explorado comercialmente por sua pele e carne. Neste trabalho, sistematizou-se os ramos colaterais viscerais da aorta abdominal. Utilizaram-se 30 nutrias, 15 fêmeas e 15 machos, com o sistema arterial aórtico-abdominal preenchido com látex 603. A aorta abdominal emitiu ventralmente como ramo colateral visceral à artéria celíaca, que se trifurcou nas artérias gástrica esquerda, hepática e lienal. Os ramos da artéria celíaca promoveram a irrigação do estômago, duodeno, fígado, pâncreas e baço. A seguir, a aorta abdominal emitiu a artéria mesentérica cranial, de calibre maior que a artéria celíaca, justaposta caudalmente. A artéria mesentérica cranial emitiu ramos, vascularizando a parte final do duodeno, lobo direito do pâncreas, jejuno, íleo, ceco, cólon maior e cólon menor. A aorta abdominal emitiu lateralmente as artérias renais direita e esquerda. As artérias adrenais foram ramos colaterais diretos das artérias renais e/ou da artéria frênico-abdominal. A artéria mesentérica caudal foi emitida da superfície ventral da aorta abdominal, próximo à sua bifurcação em artérias ilíacas comuns. A artéria mesentérica caudal lançou ramos para o cólon menor e porção cranial do reto. Os ramos colaterais viscerais diretos da aorta abdominal foram: artéria celíaca, artéria mesentérica cranial, artérias renais e artéria mesenté

Ramos colaterais viscerais da artéria aorta abdominal em Myocastor coypus (nutria)

A nutria é um roedor originário do extremo sul da América do Sul explorado comercialmente por sua pele e carne. Neste trabalho, sistematizou-se os ramos colaterais viscerais da aorta abdominal. Utilizaram-se 30 nutrias, 15 fêmeas e 15 machos, com o sistema arterial aórtico-abdominal preenchido com látex 603. A aorta abdominal emitiu ventralmente como ramo colateral visceral à artéria celíaca, que se trifurcou nas artérias gástrica esquerda, hepática e lienal. Os ramos da artéria celíaca promoveram a irrigação do estômago, duodeno, fígado, pâncreas e baço. A seguir, a aorta abdominal emitiu a artéria mesentérica cranial, de calibre maior que a artéria celíaca, justaposta caudalmente. A artéria mesentérica cranial emitiu ramos, vascularizando a parte final do duodeno, lobo direito do pâncreas, jejuno, íleo, ceco, cólon maior e cólon menor. A aorta abdominal emitiu lateralmente as artérias renais direita e esquerda. As artérias adrenais foram ramos colaterais diretos das artérias renais e/ou da artéria frênico-abdominal. A artéria mesentérica caudal foi emitida da superfície ventral da aorta abdominal, próximo à sua bifurcação em artérias ilíacas comuns. A artéria mesentérica caudal lançou ramos para o cólon menor e porção cranial do reto. Os ramos colaterais viscerais diretos da aorta abdominal foram: artéria celíaca, artéria mesentérica cranial, artérias renais e artéria mesenté

Ramos colaterais viscerais da artéria aorta abdominal em Myocastor coypus (nutria)

A nutria é um roedor originário do extremo sul da América do Sul explorado comercialmente por sua pele e carne. Neste trabalho, sistematizou-se os ramos colaterais viscerais da aorta abdominal. Utilizaram-se 30 nutrias, 15 fêmeas e 15 machos, com o sistema arterial aórtico-abdominal preenchido com látex 603. A aorta abdominal emitiu ventralmente como ramo colateral visceral à artéria celíaca, que se trifurcou nas artérias gástrica esquerda, hepática e lienal. Os ramos da artéria celíaca promoveram a irrigação do estômago, duodeno, fígado, pâncreas e baço. A seguir, a aorta abdominal emitiu a artéria mesentérica cranial, de calibre maior que a artéria celíaca, justaposta caudalmente. A artéria mesentérica cranial emitiu ramos, vascularizando a parte final do duodeno, lobo direito do pâncreas, jejuno, íleo, ceco, cólon maior e cólon menor. A aorta abdominal emitiu lateralmente as artérias renais direita e esquerda. As artérias adrenais foram ramos colaterais diretos das artérias renais e/ou da artéria frênico-abdominal. A artéria mesentérica caudal foi emitida da superfície ventral da aorta abdominal, próximo à sua bifurcação em artérias ilíacas comuns. A artéria mesentérica caudal lançou ramos para o cólon menor e porção cranial do reto. Os ramos colaterais viscerais diretos da aorta abdominal foram: artéria celíaca, artéria mesentérica cranial, artérias renais e artéria mesenté

Ramos colaterais viscerais da artéria aorta abdominal em Myocastor coypus (nutria)

A nutria é um roedor originário do extremo sul da América do Sul explorado comercialmente por sua pele e carne. Neste trabalho, sistematizou-se os ramos colaterais viscerais da aorta abdominal. Utilizaram-se 30 nutrias, 15 fêmeas e 15 machos, com o sistema arterial aórtico-abdominal preenchido com látex 603. A aorta abdominal emitiu ventralmente como ramo colateral visceral à artéria celíaca, que se trifurcou nas artérias gástrica esquerda, hepática e lienal. Os ramos da artéria celíaca promoveram a irrigação do estômago, duodeno, fígado, pâncreas e baço. A seguir, a aorta abdominal emitiu a artéria mesentérica cranial, de calibre maior que a artéria celíaca, justaposta caudalmente. A artéria mesentérica cranial emitiu ramos, vascularizando a parte final do duodeno, lobo direito do pâncreas, jejuno, íleo, ceco, cólon maior e cólon menor. A aorta abdominal emitiu lateralmente as artérias renais direita e esquerda. As artérias adrenais foram ramos colaterais diretos das artérias renais e/ou da artéria frênico-abdominal. A artéria mesentérica caudal foi emitida da superfície ventral da aorta abdominal, próximo à sua bifurcação em artérias ilíacas comuns. A artéria mesentérica caudal lançou ramos para o cólon menor e porção cranial do reto. Os ramos colaterais viscerais diretos da aorta abdominal foram: artéria celíaca, artéria mesentérica cranial, artérias renais e artéria mesenté