Embryonic and Fetal Development in - Pigmy Rice Rat - Oligoryzomys sp (Rodentia, Sigmodontinae) and its Significance for Being a new Experimental Model

Oligoryzomys (Cricetidae, Sigmodontinae) is a common rodent genus from South America that includes a couple of very similar species. Related species have been used as experimental model for understanding several diseases for which these species are reservoirs. In order to provide a better understanding of the embryological aspects of this group, herein we showed data on the embryonic and fetal development in Oligoryzomys sp. Eight specimens of different stages of gestation were obtained from the Collection of the Zoology Museum of University of Sao Paulo, Brazil. Gestational ages were estimated by crown-rump-length according to Evans and Sack (1973). To address our analysis after examining the gross morphology, tissues from several organs were processed for light and scanning electron microscopy. Morphological data on the systems (nervous system, cardiorespiratory system, intestinal tract and urogenital system) were described in detail. Finally, the findings were compared with what is known about embryological aspects in other rodent species in order to establish similarities and differences during the organogenesis in different species.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP

Peritoneopericardial Diaphragmatic Hernia in a Persian Cat

Background: Peritoneopericardial diaphragmatic hernia is a congenital defect characterized by an anomalous communication between the abdominal cavity and pericardial sac, which can lead to displacement of the abdominal viscera into the thoracic cavity. The occurrence in felines is higher among long-haired breeds, mainly the Persian breed, possibly based onan autosomal recessive inheritance. The diagnosis of PPDH is performed by means of chest radiography with or without contrast, in association with other imaging tests such as ultrasonography and echocardiography. Our objective in this study was to report the occurrence and macroscopic changes in a case of peritoneopericardial diaphragmatic hernia in a Persian feline. Case: A 9-year-old male Persian cat weighing 3.4 kg was referred to the HPET-Private Veterinary Clinic, Salvador, Bahia, with an history of weight loss and chronic intermittent vomiting during the preceding 6 months, with lateral decubitus and breathing difficulties. Ultrasonography revealed findings suggestive of an infiltrative process in the stomach and duodenum, enlarged gastric lymph nodes, and some nodular images indicating slight displacement of the liver. Chest radiography revealed a cardiac silhouette with markedly enlarged dimensions associated with a dorsal deviation of the terminal trachea, and echocardiography revealed a small amount of pericardial effusion. The patient showed initial clinical improvement after blood transfusion; however, after 2 days, he exhibited significant clinical worsening and was therefore euthanized with the owner's consent. Post mortem evaluation revealed partial herniation of the liver and gallbladder into the chest cavity through a diaphragmatic hernia ring. The heart was partially surrounded by the left medial lobe of the liver, which was displaced into the pericardial sac. Herniated hepatic lobes had an irregular capsular surface with evident lobulation and tension lipidosis. In the abdominal cavity, the remainder of the liver (right lateral and medial lobes) was observed to be slightly enlarged, with an irregular surface, diffusely reddish with intense evidence of the lobular pattern and white and firm multifocal areas (fibrosis). In the duodenum, close to the pylorus, there was a nodule measuring 2.8 x 2.5 x 1.0 cm, with a whitish and ulcerated surface. When cut, it was soft and exhibited a homogeneous, whitish compact surface.Histopathological examinationshowed marked proliferation of fibrous connective tissue, which for the most part separated the lobes by septa and surrounded the portal space (fibrosis), a marked diffuse chronic inflammatory infiltrate composed of lymphocytes and plasma cells. In addition, marked bile duct hyperplasia and multifocal areas of fatty degeneration (steatosis).Discussion: The diagnosis was based on the association of clinical and pathological findings. Considering the age and clinical signs presented by the patient in this report, as well as the presence of few radiographic signs that were indicative of PPDH, the first differential diagnosis thought was pericardial neoplasia. Peritoneopericardial diaphragmatic hernia in felines is always of congenital origin and may occur asymptomatically depending on the number and involvement of herniated viscera. In this case, the patient's diagnosis of peritoneopericardial hernia was a necropsy finding; the fact that in agreement with previous reports of high rates of incidental diagnoses reinforces the importance of performing necropsy for confirmation or diagnosis of unexpected pathologies. In the present case, peritoneopericardial diaphragmatic hernia in isolation may not have led to severe anemia that culminated in the patient's death. The anatomopathological findings were compatible with biliary cirrhosis and multifocal liver fibrosis, accompanied by the presence of anemia and consequent hypovolemia. Keywords: congenital diaphragmatic hernia, congenital abnormalities, cats. Título: Hérnia Diafragmática Peritoneopericárdica em um Felino da Raça PersaDescritores: hérnia diafragmática congênita, anomalias congênitas, felinos.

Comparative aspects among the irrigation types of both ventricular and sinoatrial node in cats

Utilizou-se 30 corações de gatos sem raça definida, machos e fêmeas, adultos de idades variadas que não portavam nenhuma afecção cardíaca. Os corações foram injetados pela aorta torácica com Neoprene Latex 450, corados com pigmento vermelho. Verificou-se quando do predomínio da vascularização ventricular do tipo esquerda (63,34%) que a região irrigada pelo nó sinoatrial fica predominantemente na dependência do ramo proximal atrial direito (78,9%) ou com menor freqüência pelo ramo proximal atrial esquerdo (21,1%). Quando ocorreu a vascularização ventricular do tipo equilibrada (33,34%), a região ocupada pelo nó sinoatrial ficou na dependência mais frequentemente do ramo proximal atrial direito (80%), ou com menor freqüência a nutrição do nó se deu pelo ramo proximal atrial esquerdo (20%). Em um caso isolado, onde ocorreu a vascularização ventricular do tipo direita (3,34%), a nutrição da área ocupada pelo nó sinoatrial, ficou na dependência exclusiva do ramo intermédio atrial direito. Estes resultados indicam que nesta espécie não existe nenhuma relação entre a irrigação do nó sinoatrial e o tipo de vascularização ventricular.We analyzed 30 hearts of cats without pedigree, males and females, adults of several ages. They were not carrying any heart problems. The hearts were injected by the thoracic aorta with Neoprene Latex 450 and stained with red pigment. We analyzed the prevalence of ventricular vascularization of the left type (63.34%) the irrigated region by the sinoatrial node was predominantly in the dependency of the Ramus proximalis atrii dextri (78.9%) or with less frequency by Ramus proximalis atrii sinister (21.1%). When occurred the ventricular vascularization of the type balanced (33.34%), the region occupied by the sinoatrial node was in the responsibility more often of the Ramus proximalis atrii dextri (80%) or with less frequency the nutrition of the sinoatrial node occurred by Ramus proximalis atril sinister (20%). In a singlecase, where we observed the ventricular vascularization of the right type (3.34%), the nutrition of the area occupied by the sinoatrial node, was the exclusive dependence of the Ramus intermedius atril dextri. These results showed that this specie there are no relationship between both the sinoatrial node irrigation and the type of ventricular vascularization, therefore, the nutrition of the sinoatrial node does not depend on the type of the ventricles vascularization

Comparative apects among the vascularization types of both ventricular and sinoatrial node in dogs

Utilizamos nesta pesquisa 40 corações de cães adultos, 17 machos e 23 fêmeas, de idades variadas, que não portavam macroscopicamente nenhuma afecção cardíaca. Os corações tiveram as artérias coronárias injetadas, separadamente, com Neoprene Látex 450, corado com pigmento vermelho, e posteriormente dissecados. Em todas estas preparações verificamos que na vascularização dos ventrículos predominava a artéria coronária esquerda que fornecia os ramos interventriculares paraconal e subsinuoso. Já, a região ocupada pelo nó sinoatrial ficava mais frequentemente (17 vezes 42,5%) na dependência do ramo proximal atrial esquerdo ou de colateral deste vaso, oriundo do ramo circunflexo esquerdo, ou deste vaso associado ao ramo distal atrial direito (8 vezes 20%), procedente do ramo circunflexo direito. Com menor frequência (14 vezes 30%), a área tomada pelo nó sinoatrial, encontramos apenas colaterais do ramo circunflexo direito, mais exatamente somente o ramo distal atrial direito (10 vezes 25%), apenas o ramo proximal atrial direito (3 vezes 7,5%) ou ainda exclusivamente o ramo intermédio atrial direito (1 vez 2,5%). Em um único caso (1 vez 2,5%) no território do nó sinoatrial observamos apenas colateral do ramo circunflexo esquerdo, isto é o ramo distal atrial esquerdo. A análise destes resultados permite concluir, que nesta espécie não existe qualquer tipo de relação entre o tipo de vascularização dos ventrículos e a irrigação do nó sinoatrial.In this research we analyzed 40 hearts of adult dogs, males and females with different ages, which had no cardiac disease. The hearts had the coronary arteries inject using Neoprene Latex 450, stained by red pigment and then were dissected. In the ventricular vascularization the left coronary artery was predominant and it gave rise to the branches paraconal interventricular and subsinuous. The region occupied by the sinoatrial node was most frequently (17 times 42.5%) in the dependence of the left atrial proximal branch or in the collateral of that vessel, coming from the left circumflex branch, or this vessel associated to the right atrial distal branch (8 times 20%). With less frequency (14 times 30%), in the area occupied by the sinoatrial node, we found only the collaterals of the right circumflex branch, rather only the right atrial distal branch (10 times 25%), only the right atrial proximal branch (3 times 7.5%) or exclusively through the right atrial intermediary branch (1 time 2.5%). In just one case (Once 2.5%) in the area of the sinoatrial node we observed only the collateral of the left circumflex branch, i.e. the left atrial distal branch. According to our results we concluded that in this specie there are no relation between the type of vascularization of the ventricles and the irrigation of the sinoatrial node

Comparative apects among the vascularization types of both ventricular and sinoatrial node in dogs

Utilizamos nesta pesquisa 40 corações de cães adultos, 17 machos e 23 fêmeas, de idades variadas, que não portavam macroscopicamente nenhuma afecção cardíaca. Os corações tiveram as artérias coronárias injetadas, separadamente, com Neoprene Látex 450, corado com pigmento vermelho, e posteriormente dissecados. Em todas estas preparações verificamos que na vascularização dos ventrículos predominava a artéria coronária esquerda que fornecia os ramos interventriculares paraconal e subsinuoso. Já, a região ocupada pelo nó sinoatrial ficava mais frequentemente (17 vezes 42,5%) na dependência do ramo proximal atrial esquerdo ou de colateral deste vaso, oriundo do ramo circunflexo esquerdo, ou deste vaso associado ao ramo distal atrial direito (8 vezes 20%), procedente do ramo circunflexo direito. Com menor frequência (14 vezes 30%), a área tomada pelo nó sinoatrial, encontramos apenas colaterais do ramo circunflexo direito, mais exatamente somente o ramo distal atrial direito (10 vezes 25%), apenas o ramo proximal atrial direito (3 vezes 7,5%) ou ainda exclusivamente o ramo intermédio atrial direito (1 vez 2,5%). Em um único caso (1 vez 2,5%) no território do nó sinoatrial observamos apenas colateral do ramo circunflexo esquerdo, isto é o ramo distal atrial esquerdo. A análise destes resultados permite concluir, que nesta espécie não existe qualquer tipo de relação entre o tipo de vascularização dos ventrículos e a irrigação do nó sinoatrial.In this research we analyzed 40 hearts of adult dogs, males and females with different ages, which had no cardiac disease. The hearts had the coronary arteries inject using Neoprene Latex 450, stained by red pigment and then were dissected. In the ventricular vascularization the left coronary artery was predominant and it gave rise to the branches paraconal interventricular and subsinuous. The region occupied by the sinoatrial node was most frequently (17 times 42.5%) in the dependence of the left atrial proximal branch or in the collateral of that vessel, coming from the left circumflex branch, or this vessel associated to the right atrial distal branch (8 times 20%). With less frequency (14 times 30%), in the area occupied by the sinoatrial node, we found only the collaterals of the right circumflex branch, rather only the right atrial distal branch (10 times 25%), only the right atrial proximal branch (3 times 7.5%) or exclusively through the right atrial intermediary branch (1 time 2.5%). In just one case (Once 2.5%) in the area of the sinoatrial node we observed only the collateral of the left circumflex branch, i.e. the left atrial distal branch. According to our results we concluded that in this specie there are no relation between the type of vascularization of the ventricles and the irrigation of the sinoatrial node

Peritoneopericardial Diaphragmatic Hernia in a Persian Cat

Background: Peritoneopericardial diaphragmatic hernia is a congenital defect characterized by an anomalous communication between the abdominal cavity and pericardial sac, which can lead to displacement of the abdominal viscera into the thoracic cavity. The occurrence in felines is higher among long-haired breeds, mainly the Persian breed, possibly based onan autosomal recessive inheritance. The diagnosis of PPDH is performed by means of chest radiography with or without contrast, in association with other imaging tests such as ultrasonography and echocardiography. Our objective in this study was to report the occurrence and macroscopic changes in a case of peritoneopericardial diaphragmatic hernia in a Persian feline. Case: A 9-year-old male Persian cat weighing 3.4 kg was referred to the HPET-Private Veterinary Clinic, Salvador, Bahia, with an history of weight loss and chronic intermittent vomiting during the preceding 6 months, with lateral decubitus and breathing difficulties. Ultrasonography revealed findings suggestive of an infiltrative process in the stomach and duodenum, enlarged gastric lymph nodes, and some nodular images indicating slight displacement of the liver. Chest radiography revealed a cardiac silhouette with markedly enlarged dimensions associated with a dorsal deviation of the terminal trachea, and echocardiography revealed a small amount of pericardial effusion. The patient showed initial clinical improvement after blood transfusion; however, after 2 days, he exhibited significant clinical worsening and was therefore euthanized with the owner's consent. Post mortem evaluation revealed partial herniation of the liver and gallbladder into the chest cavity through a diaphragmatic hernia ring. The heart was partially surrounded by the left medial lobe of the liver, which was displaced into the pericardial sac. Herniated hepatic lobes had an irregular capsular surface with evident lobulation and tension lipidosis. In the abdominal cavity, the remainder of the liver (right lateral and medial lobes) was observed to be slightly enlarged, with an irregular surface, diffusely reddish with intense evidence of the lobular pattern and white and firm multifocal areas (fibrosis). In the duodenum, close to the pylorus, there was a nodule measuring 2.8 x 2.5 x 1.0 cm, with a whitish and ulcerated surface. When cut, it was soft and exhibited a homogeneous, whitish compact surface.Histopathological examinationshowed marked proliferation of fibrous connective tissue, which for the most part separated the lobes by septa and surrounded the portal space (fibrosis), a marked diffuse chronic inflammatory infiltrate composed of lymphocytes and plasma cells. In addition, marked bile duct hyperplasia and multifocal areas of fatty degeneration (steatosis).Discussion: The diagnosis was based on the association of clinical and pathological findings. Considering the age and clinical signs presented by the patient in this report, as well as the presence of few radiographic signs that were indicative of PPDH, the first differential diagnosis thought was pericardial neoplasia. Peritoneopericardial diaphragmatic hernia in felines is always of congenital origin and may occur asymptomatically depending on the number and involvement of herniated viscera. In this case, the patient's diagnosis of peritoneopericardial hernia was a necropsy finding; the fact that in agreement with previous reports of high rates of incidental diagnoses reinforces the importance of performing necropsy for confirmation or diagnosis of unexpected pathologies. In the present case, peritoneopericardial diaphragmatic hernia in isolation may not have led to severe anemia that culminated in the patient's death. The anatomopathological findings were compatible with biliary cirrhosis and multifocal liver fibrosis, accompanied by the presence of anemia and consequent hypovolemia. Keywords: congenital diaphragmatic hernia, congenital abnormalities, cats. Título: Hérnia Diafragmática Peritoneopericárdica em um Felino da Raça PersaDescritores: hérnia diafragmática congênita, anomalias congênitas, felinos.