PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Anjos B.L., Irigoyen L.F., Piazer J.V.M., Brum J.S., Fighera R.A. & Barros C.S.L. 2009. [Experimental acute poisoning by bracken fern (Pteridium aquilinum) in cattle.] Intoxicação experimental aguda por samambaia (Pteridium aquilinum) em bovinos. Pesquisa Veterinária Brasileira 29(9):753-766. Departamento de Patologia, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: claudioslbarros@uol.com.br This experiment was design to address the following points in relation to the acute poisoning by bracken fern (Pteridium aquilinum) in cattle: 1) the severity of the thrombocytopenia in different stages of the intoxication and its relationship to possible deficits in the secondary hemostasis, 2) the relationship between neutropenia and the morphological signs of septicemia occasionally found at necropsy, and 3) the mechanism of anemia and its relationship with blood loss, medium life of erythrocytes and the progress of the disease. The fresh green upper parts of P. aquilinum were fed to four mixed breed calves with average age of 18 months and weights ranging from 190 to 215 kg. A calf of similar age and weight was kept together with the other four under the same conditions, except for the ingestion of P. aquilinum. The four fern-fed calves died with typical features of acute bracken fern poisoning after being fed with the plant for 53-58 days daily doses of 8.0, 8.6, 10.2, and 10.6g/kg body weight totaling at the end of the experiment, respectively, 59.3%, 63.3%, 47.4%, and 47.5% of bracken fern in relation to their body weight. The disease was characterized by fever up to 42.5°C and varying degrees of hemorrhages observed clinically, at necropsy and on histological examination. Death occurred 6-7 days after the onset of fever. The hematological changes consisted mainly of marked thrombocytopenia and neutropenia. Two of the four affected calves had mild anemia. The deficits in secondary hemostasis were mild in each case. There were no significant changes thus permitting to rule out the role of secondary hemostasis in the pathogenesis of the hemorrhages in the bracken fern poisoning. The measurement of fibrin degradation products in the serum showed conflicting results and did no allow for a solid conclusion regarding the role of disseminated intravascular coagulation in the pathogenesis of the hemorrhages in fern poisoning. The cytology and the histopathology of bone marrow from the four poisoned calves revealed marked decrease in the numbers of hematopoietic cells from the three marrow lineages, which characterizes marrow failure due to aplasia; it was concluded that the events of the primary hemostasis due to thrombocytopenia are responsible for the hemorrhages. In blood culture from three affected calves there was growth of Klebsiella oxytoca, Staphylococcus hyicus and Staphylococcus aureus, indicating that septicemia, facilitated by neutropenia could have a role in the death of cattle acutely poisoned due to the ingestion of P. aquilinum. Additional points of the interest in the acute experimental poisoning by bracken fern in cattle reported here were the development of hematuria and the so called laryngeal form.

• Poisonous plants bracken fern Pteridium aquilinum plant poisoning plantas tóxicas samambaia intoxicação por planta

Abstract in Portuguese:

RESUMO.- Anjos B.L., Irigoyen L.F., Piazer J.V.M., Brum J.S., Fighera R.A. & Barros C.S.L. 2009. [Experimental acute poisoning by bracken fern (Pteridium aquilinum) in cattle.] Intoxicação experimental aguda por samambaia (Pteridium aquilinum) em bovinos. Pesquisa Veterinária Brasileira 29(9):753-766. Departamento de Patologia, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: claudioslbarros@uol.com.br Este experimento foi delineado para investigar os seguintes pontos em relação à intoxicação aguda por samambaia (Pteridium aquilinum) em bovinos: 1) a intensidade da trombocitopenia em diferentes momentos da intoxicação e sua relação com possíveis déficits na hemostasia secundária, 2) a relação da neutropenia com as manifestações morfológicas de septicemia ocasionalmente observadas na necropsia, e 3) o mecanismo da anemia e sua relação com a perda de sangue, a vida média eritróide e a evolução da doença. As hastes superiores mais verdes de P. aquilinum foram administradas a quatro bovinos sem raça definida, com idade média de 1,5 ano e pesos entre 190-215 kg. Um bovino de idade e peso semelhantes foi usado como controle e, exceto por não ter recebido P. aquilinum, foi mantido nas mesmas condições que os outros quatro. Os quatro bovinos que receberam a planta morreram com quadro característico da intoxicação aguda por samambaia após receberem durante 53-58 dias, doses diárias de 8,0, 8,6, 10,2 e 10,6g/kg de peso corporal, que totalizaram, ao final do experimento, respectivamente, 112,7, 107,6, 85,7, 90,15 kg da planta, o que corresponde, respectivamente, a 59,3%, 63,3%, 47,4%, 47,5% da planta em relação ao peso dos bovinos. A doença caracterizou-se por febre de até 42,5°C e diversos graus de hemorragias observadas clinicamente, na necropsia e na histopatologia. A morte ocorria 6-7 dias após o início do quadro febril. As alterações hematológicas revelaram trombocitopenia e neutropenia acentuadas. Em dois dos quatro bovinos havia anemia leve. Não houve variações significativas nos tempos de coagulação dos bovinos intoxicados, quando avaliados os fatores de coagulação (secundária), excluindo-se assim a possibilidade da participação de distúrbios da hemostasia secundária na patogênese das hemorragias nessa intoxicação. A determinação dos produtos da degradação da fibrina no soro revelou dados conflitantes, não permitindo concluir se a coagulação intravascular disseminada tem participação na patogênese das hemorragias nessa intoxicação. A citopatologia e histopatologia da medula óssea dos quatro bovinos intoxicados revelaram acentuada diminuição no número de células hematopoéticas das três linhagens medulares, caracterizando insuficiência medular por aplasia; conclui-se que apenas eventos da hemostasia primária devidos a trombocitopenia são responsáveis pelas hemorragias. Na hemocultura de três dos bovinos intoxicados houve crescimento de Klebsiella oxytoca, Staphylococcus hyicus e Staphylococcus aureus, indicando que a septicemia, facilitada pela neutropenia, pode ter participação na causa da morte de bovinos na intoxicação aguda pela ingestão de P. aquilinum. Aspectos adicionais de interesse na reprodução da intoxicação aguda por samambaia em bovinos deste relato incluem o desenvolvimento de hematúria na doença aguda e a apresentação da chamada forma laríngea da doença.

Abstract in English:

ABSTRACT.- Camplesi A.C., Sakate M., Simão N.M.B. & Moya C.F. 2009. [Dosing cardiac markers CK-MB and TnIc and electrolytes in experimental toad envenoming in dogs.] Dosagem de marcadores cardíacos CK-MB e TnIc e eletrólitos no envenenamento experimental por veneno de sapo em cães. Pesquisa Veterinária Brasileira 29(8):632-636. Departamento de Clínica Médica Veterinária, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, SP 18600-000, Brazil. E-mail: annecamplesi@yahoo.com.br Among the systemic signs of toad venom (bufotoxin) poisoning in dogs, the cardiotoxic effects are one of the most important. Thus, the objective of this experiment was to evaluate potential changes in the cardiac muscle in dogs poisoned experimentally by toad venom and to observe the eletrolyte alterations which may occur in this condition. Twenty dogs divided into control group (n=5) and poisoned group (n=15) were utilized. The toad venom was extracted by manual compression of the paratoidic glands. After general anesthesia, dogs in the control group received placebo and dogs in the poisoned group received the venom by orogastric catheter. Samples for dosage were collected 6 hours and 24 hours after poisoning and 0, 2, 4, 6 and 12 hours after poisoning for electrolytes dosage. The Man-Withney test was used for statistical analysis (P<0.05). The poisoned dogs showed (saline) elevated levels of cardiac markers CK-MB and TnIc, confirming the cardiotoxic effect of the bufotoxin. Hypokalemia and hypocalcemia were also observed.

• Toad venom poisoning bufotoxin

Abstract in Portuguese:

RESUMO.- Camplesi A.C., Sakate M., Simão N.M.B. & Moya C.F. 2009. [Dosing cardiac markers CK-MB and TnIc and electrolytes in experimental toad envenoming in dogs.] Dosagem de marcadores cardíacos CK-MB e TnIc e eletrólitos no envenenamento experimental por veneno de sapo em cães. Pesquisa Veterinária Brasileira 29(8):632-636. Departamento de Clínica Médica Veterinária, Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, SP 18600-000, Brazil. E-mail: annecamplesi@yahoo.com.br Dentre os sinais sistêmicos causados pelo envenenamento por veneno de sapo (bufotoxina) em cães, os efeitos cardiotóxicos são um dos mais importantes. O objetivo deste estudo foi avaliar as potenciais alterações no músculo cardíaco de cães envenenados experimentalmente por veneno de sapo e observar as alterações eletrolíticas que podem ocorrer nesse tipo de envenenamento. Utilizaram-se 20 cães divididos em grupo controle (n=5) e grupo envenenado (n=15). O veneno de sapo foi extraído por meio de compressão manual das glândulas paratóides. Após anestesia geral, os cães do grupo controle receberam placebo (solução fisiológica) e os do grupo envenenado uma alíquota do veneno por sonda orogástrica. As colheitas de sangue para dosagem dos marcadores cardíacos foram realizadas seis e 24 horas após o envenenamento. As colheitas de sangue para dosagem dos eletrólitos foram realizadas antes e duas, quatro, seis e 12 horas após o envenenamento. A análise estatística empregada foi o teste não-paramétrico de Mann-Withney (P<0,05). Os cães envenenados por veneno de sapo apresentaram elevação dos níveis dos marcadores cardíacos CK-MB e TnIc, confirmando a cardiotoxicidade do veneno. Hipocalemia e hipocalcemia foram também observadas nos cães envenenados.

Abstract in English:

ABSTRACT.- Oliveira R.R., Mamprim M.J., Rahal S.C. & Bicudo A.L.C. 2009. [Radiography and ultrasonography in the diagnosis of rupture of the cranial cruciate ligament in dogs.] Radiografia e ultrassonografia no diagnóstico da ruptura do ligamento cruzado cranial em cães. Pesquisa Veterinária Brasileira 29(8):661-665. Departamento de Patologia Geral, Universidade Estadual do Paraná, Cx. Postal 261, Bandeirantes, PR 86360-000, Brazil. E-mail: rodrigoreisvet@hotmail.com Radiography and ultrasonography were evaluated as tools for diagnosis of the rupture of cranial cruciate ligament (CrCL) in dogs. Twenty-five dogs were submitted to radiographic and ultrasonographic examinations and their results were compared with those obtained by artrotomy (gold standard). Radiography detected the rupture in 84% (21/25) of the cases, but 16% (4/25) were false-negative. Ultrasonography identified accurately 76% (19/25) of the cases and gave a probable diagnosis for the remaining 24% (6/25) what means that this technique presented 100% of positive results. It was possible to conclude that radiography and ultrasonography are valuable tools for the diagnosis of CrCL rupture in dogs.

• Cruciate ligament

Abstract in Portuguese:

RESUMO.- ABSTRACT.- Oliveira R.R., Mamprim M.J., Rahal S.C. & Bicudo A.L.C. 2009. [Radiography and ultrasonography in the diagnosis of rupture of the cranial cruciate ligament in dogs.] Radiografia e ultrassonografia no diagnóstico da ruptura do ligamento cruzado cranial em cães. Pesquisa Veterinária Brasileira 29(8):661-665. Departamento de Patologia Geral, Universidade Estadual do Paraná, Cx. Postal 261, Bandeirantes, PR 86360-000, Brazil. E-mail: rodrigoreisvet@hotmail.com Radiografia e ultrassonografia foram avaliadas como técnicas no diagnóstico por imagem na ruptura do ligamento cruzado cranial (LCCr) em cães. Vinte e cinco cães foram submetidos à radiografia e ultrassonografia e seus resultados foram comparados aos obtidos por artrotomia (teste padrão ouro). O exame radiográfico diagnosticou corretamente a lesão em 84% (21/25) dos casos, mas 16% (4/25) apresentaram resultado falso-negativo. O exame ultrassonográfico foi capaz de diagnosticar acertadamente 76% (19/25) dos casos, e sugeriu a ruptura do LCCr nos 24% (6/25) restantes, apresentando 100% de resultados positivos. Concluiu-se que a radiografia e a ultrassonografia são ferramentas valiosas para diagnosticar casos de ruptura do LCCr em cães.

Abstract in English:

ABSTRACT.- Mendes H.M.F., Escobar A., Vasconcelos A.C., Zucoloto S., Alves G.E.S. & Faleiros R.R. 2009. [Morphometrical alterations in myoenteric plexus of experimentally distended equine small colon.] Alterações morfométricas no plexo mioentérico do cólon menor equino distendido experimentalmente. Pesquisa Veterinária Brasileira 29(7):557-562. Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, MG 30161-970, Brazil. E-mail: faleiros@ufmg.br The equine small colon is frequently affected by obstruction, and intestinal motility dysfunction is a common complication after its surgical treatment. This fact may be related to myoenteric plexus lesion caused by distention; however, little is known about the pathophysiology of this condition. The objective of this study was to evaluate the morphological alterations in the myoenteric inervation of segments of small colon of horses subjected to intraluminal distension with reduction of the microvascular perfusion (partial ischemia) of the intestinal wall. Nine horses were used to promote distension of on segment of small colon for 4 hours. Samples of intestinal wall were collected before and at the end of the distension, after 1.5 and 12 hours of reperfusion in the experimental segment and at the end of the procedure in a different distant segment. Samples were processed and histological sections were stained with cresyl violet for the morphometric studies. An image analyzer software was used to measure perimeter, diameter, and area of the neuronal body, nucleus and nucleolus of the neurons and the areas of the cytoplasm and nucleoplasm. Significant reductions (P<0.05) in the areas of the neuronal body and cytoplasm were detected at the end of intestinal distension, returning to the basal values during the reperfusion. In conclusion, intraluminal distension promoted changes in the morphology of the neurons of myoenteric plexus. These morphological modifications may be associated to the motility dysfunction frequently observed in clinical cases.

• Small colon distension myoenteric plexus horse

Abstract in Portuguese:

ABSTRACT.- Mendes H.M.F., Escobar A., Vasconcelos A.C., Zucoloto S., Alves G.E.S. & Faleiros R.R. 2009. [Morphometrical alterations in myoenteric plexus of experimentally distended equine small colon.] Alterações morfométricas no plexo mioentérico do cólon menor equino distendido experimentalmente. Pesquisa Veterinária Brasileira 29(7):557-562. Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, MG 30161-970, Brazil. E-mail: faleiros@ufmg.br The equine small colon is frequently affected by obstruction, and intestinal motility dysfunction is a common complication after its surgical treatment. This fact may be related to myoenteric plexus lesion caused by distention; however, little is known about the pathophysiology of this condition. The objective of this study was to evaluate the morphological alterations in the myoenteric inervation of segments of small colon of horses subjected to intraluminal distension with reduction of the microvascular perfusion (partial ischemia) of the intestinal wall. Nine horses were used to promote distension of on segment of small colon for 4 hours. Samples of intestinal wall were collected before and at the end of the distension, after 1.5 and 12 hours of reperfusion in the experimental segment and at the end of the procedure in a different distant segment. Samples were processed and histological sections were stained with cresyl violet for the morphometric studies. An image analyzer software was used to measure perimeter, diameter, and area of the neuronal body, nucleus and nucleolus of the neurons and the areas of the cytoplasm and nucleoplasm. Significant reductions (P<0.05) in the areas of the neuronal body and cytoplasm were detected at the end of intestinal distension, returning to the basal values during the reperfusion. In conclusion, intraluminal distension promoted changes in the morphology of the neurons of myoenteric plexus. These morphological modifications may be associated to the motility dysfunction frequently observed in clinical cases.

Abstract in English:

ABSTRACT.- Câmara A.C.L., Afonso J.A.B., Costa N.A., Mendonça C.L. & Souza M.I. 2009. [Primary abomasal impaction in 14 cattle from Pernambuco State, northeastern Brazil.] Compactação primária do abomaso em 14 bovinos no Estado de Pernambuco. Pesquisa Veterinária Brasileira 29(5):387-394. Clínica de Bovinos, Campus Garanhuns, Universidade Federal Rural de Pernambuco, Av. Bom Pastor s/n, Cx. Postal 152, Mundaú, Garanhuns, PE 55292-901, Brazil. E-mail: aclcamara@yahoo.com.br Despite the frequent use of dry and fibrous roughage for feeding cows in many regions, especially during the dry season, impaction of the abomasum has been poorly reported in Brazil, probably because the condition is misdiagnosed by practitioners. The present paper aimed to accomplish a retrospective study on primary abomasal impaction in 14 cattle from Pernambuco State, northeastern Brazil. Eight moderate cases, without severe abdominal distention and with no rumen compaction, were treated conservatively, and four severe cases, with severe abdominal distention and rumen compaction, were treated surgically. One bull was slaughtered and one cow died without treatment. The greater number of abomasal impaction cases was in Holstein cows with six cases (42.9%), followed by crossbred cattle with five cases (35.8%), and the breeds Brown-Swiss, Nelore and Marchigiana, each with one case (21.3%). The food composition was characterized by low quality fibers and varied greatly among cases. Most frequent clinical signs were apathy, dehydration, hypomotility and ruminal bloat, intestinal hypomotility and scanty or absent feces with mucus. The hematological findings revealed leukocytosis with neutrophilia and hyperfibrinogenemia in most cases. Ruminal fluid analysis showed compromised flora and fauna dynamics and increased chlorine ion concentration. Clinical (4/8) and chirurgical (2/4) recovery rate achieved 50%. The clinical and chirurgical methods remain as viable options for the treatment of light and severe impaction, but the prognosis is always reserved especially when associated to late pregnancy.

• Impaction vagal indigestion Compactação indigestão vagal

Abstract in Portuguese:

ABSTRACT.- Câmara A.C.L., Afonso J.A.B., Costa N.A., Mendonça C.L. & Souza M.I. 2009. [Primary abomasal impaction in 14 cattle from Pernambuco State, northeastern Brazil.] Compactação primária do abomaso em 14 bovinos no Estado de Pernambuco. Pesquisa Veterinária Brasileira 29(5):387-394. Clínica de Bovinos, Campus Garanhuns, Universidade Federal Rural de Pernambuco, Av. Bom Pastor s/n, Cx. Postal 152, Mundaú, Garanhuns, PE 55292-901, Brazil. E-mail: aclcamara@yahoo.com.br Despite the frequent use of dry and fibrous roughage for feeding cows in many regions, especially during the dry season, impaction of the abomasum has been poorly reported in Brazil, probably because the condition is misdiagnosed by practitioners. The present paper aimed to accomplish a retrospective study on primary abomasal impaction in 14 cattle from Pernambuco State, northeastern Brazil. Eight moderate cases, without severe abdominal distention and with no rumen compaction, were treated conservatively, and four severe cases, with severe abdominal distention and rumen compaction, were treated surgically. One bull was slaughtered and one cow died without treatment. The greater number of abomasal impaction cases was in Holstein cows with six cases (42.9%), followed by crossbred cattle with five cases (35.8%), and the breeds Brown-Swiss, Nelore and Marchigiana, each with one case (21.3%). The food composition was characterized by low quality fibers and varied greatly among cases. Most frequent clinical signs were apathy, dehydration, hypomotility and ruminal bloat, intestinal hypomotility and scanty or absent feces with mucus. The hematological findings revealed leukocytosis with neutrophilia and hyperfibrinogenemia in most cases. Ruminal fluid analysis showed compromised flora and fauna dynamics and increased chlorine ion concentration. Clinical (4/8) and chirurgical (2/4) recovery rate achieved 50%. The clinical and chirurgical methods remain as viable options for the treatment of light and severe impaction, but the prognosis is always reserved especially when associated to late pregnancy.

Abstract in English:

Abstract.- Pedroso P.M.O., Bandarra P.M., Bezerra Júnior P.S., Raymundo D.L., Borba M.R., Leal J.S. & Driemeier D. 2009. [Natural and experimental poisoning by Nerium oleander (Apocynaceae) in cattle in Rio Grande do Sul.] Intoxicação natural e experimental por Nerium oleander (Apocynaceae) em bovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(5):404-408. Setor de Patologia Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br This paper describes natural and experimental poisoning of cattle by Nerium oleander in Rio Grande do Sul. Two out of eight cattle died acutely after consumption of leaves of Nerium oleander, branches of which had been cut and placed into a paddock where the animals were kept. An affected cow did not show clinical signs, but a 4-month-old calf presented lateral recumbence, paddling, vocalization and death. Main gross findings in the cow naturally poisoned and in two experimentally intoxicated heifers were observed in the heart and included hemorrhages in the left atrium, clots and hemorrhages in the left ventricular endocardium, and pale areas in the interventricular septum and ventricular myocardium. Histologically, there was coagulation necrosis of individual cardiac fibers or small groups of fibers, characterized by enhanced cytoplasmic eosinophily and picnotic nuclei. These lesions were most severe in the papillary muscle. The diagnosis was based on presence of the trimmed N. oleander in the paddock where the animals stayed, evidence of consumption of the plant, consistent clinical and pathological findings, and experimental reproduction of the disease through oral administration of 0.5 and 1.0g/kg of its green leaves to two cattle.

• Nerium oleander plant poisoning poisonous plant intoxicação por planta plantas tóxicas Apocynaceae

Abstract in Portuguese:

Abstract.- Pedroso P.M.O., Bandarra P.M., Bezerra Júnior P.S., Raymundo D.L., Borba M.R., Leal J.S. & Driemeier D. 2009. [Natural and experimental poisoning by Nerium oleander (Apocynaceae) in cattle in Rio Grande do Sul.] Intoxicação natural e experimental por Nerium oleander (Apocynaceae) em bovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(5):404-408. Setor de Patologia Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br This paper describes natural and experimental poisoning of cattle by Nerium oleander in Rio Grande do Sul. Two out of eight cattle died acutely after consumption of leaves of Nerium oleander, branches of which had been cut and placed into a paddock where the animals were kept. An affected cow did not show clinical signs, but a 4-month-old calf presented lateral recumbence, paddling, vocalization and death. Main gross findings in the cow naturally poisoned and in two experimentally intoxicated heifers were observed in the heart and included hemorrhages in the left atrium, clots and hemorrhages in the left ventricular endocardium, and pale areas in the interventricular septum and ventricular myocardium. Histologically, there was coagulation necrosis of individual cardiac fibers or small groups of fibers, characterized by enhanced cytoplasmic eosinophily and picnotic nuclei. These lesions were most severe in the papillary muscle. The diagnosis was based on presence of the trimmed N. oleander in the paddock where the animals stayed, evidence of consumption of the plant, consistent clinical and pathological findings, and experimental reproduction of the disease through oral administration of 0.5 and 1.0g/kg of its green leaves to two cattle.

Abstract in English:

ABSTRACT.- Santos-Rodrigues A., Dagli M.L.Z., Avanzo J.L., Moraes H.P., Mackowiak I.I. & Hernandez-Blazquez F.J. 2009. Expression and distribution of connexin 32 in rat liver with experimentally induced fibrosis. Pesquisa Veterinária Brasileira 29(4):353-357. Departamento de Cirurgia, Setor de Anatomia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: alexsantos@usp.br The connexin 32 (Cx32) is a protein that forms the channels that promote the gap junction intercellular communication (GJIC) in the liver, allowing the diffusion of small molecules through cytosol from cell-to-cell. Hepatic fibrosis is characterized by a disruption of normal tissue architeture by cellular lesions, and may alter the GJIC. This work aimed to study the expression and distribution of Cx32 in liver fibrosis induced by the oral administration of dimethylnitrosamine in female Wistar rats. The necropsy of the rats was carried out after five weeks of drug administration. They presented a hepatic fibrosis state. Sections from livers with fibrosis and from control livers were submitted to immunohistochemical, Real Time-PCR and Western-Blot analysis to Cx32. In fibrotic livers the Cxs were diffusely scattered in the cytoplasm, contrasting with the control livers, where the Cx32 formed junction plaques at the cell membrane. Also it was found a decrease in the gene expression of Cx32 without reduction in the protein quantity when compared with controls. These results suggest that there the mechanism of intercellular communication between hepatocytes was reduced by the fibrotic process, which may predispose to the occurrence of a neoplastic process, taken in account that connexins are considered tumor suppressing genes.

• Dimethylnitrosamine fibrosis liver Cx32 gap junctions

Abstract in Portuguese:

ABSTRACT.- Santos-Rodrigues A., Dagli M.L.Z., Avanzo J.L., Moraes H.P., Mackowiak I.I. & Hernandez-Blazquez F.J. 2009. Expression and distribution of connexin 32 in rat liver with experimentally induced fibrosis. Pesquisa Veterinária Brasileira 29(4):353-357. Departamento de Cirurgia, Setor de Anatomia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: alexsantos@usp.br The connexin 32 (Cx32) is a protein that forms the channels that promote the gap junction intercellular communication (GJIC) in the liver, allowing the diffusion of small molecules through cytosol from cell-to-cell. Hepatic fibrosis is characterized by a disruption of normal tissue architeture by cellular lesions, and may alter the GJIC. This work aimed to study the expression and distribution of Cx32 in liver fibrosis induced by the oral administration of dimethylnitrosamine in female Wistar rats. The necropsy of the rats was carried out after five weeks of drug administration. They presented a hepatic fibrosis state. Sections from livers with fibrosis and from control livers were submitted to immunohistochemical, Real Time-PCR and Western-Blot analysis to Cx32. In fibrotic livers the Cxs were diffusely scattered in the cytoplasm, contrasting with the control livers, where the Cx32 formed junction plaques at the cell membrane. Also it was found a decrease in the gene expression of Cx32 without reduction in the protein quantity when compared with controls. These results suggest that there the mechanism of intercellular communication between hepatocytes was reduced by the fibrotic process, which may predispose to the occurrence of a neoplastic process, taken in account that connexins are considered tumor suppressing genes.

Abstract in English:

ABSTRACT.- Sampaio R.S., Lacerda M.S., Oliveira P.C.L., Paneto J.C.C., Bittar E.R., Borges G.A., Camacho G.M.M. & Braga E.M. 2009. [Variation of the resistance force to the micro-traction of fragments of cortical bones preserved in several means and fresh: Experimental study in rabbits.] Variação da força de resistência à micro-tração de fragmentos de ossos corticais preservados e a fresco: estudo experimental em coelhos. Pesquisa Veterinária Brasileira 29(4):345-352. Instituto de Estudos Avançados em Veterinária “José Caetano Borges”, Universidade de Uberaba, Av. Afrânio Azevedo 2140, Bairro Olinda, Uberaba, MG 38020-450, Brazil. E-mail: relisampa@terra.com.br Due to the increasing use of cortical bone allografts in orthopedic surgeries, de knowledge of its biomechanics characteristics during preservation time is needed. The present study consisted in the analyses of the resistance power to the micro-traction of samples of rabbit cortical bones preserved in several means for up to 180 days and fresh. The results showed that the resistance and the preservation time presented an inversely proportional relation, meaning that, the longer the time of preservation, the shorter the physical resistance evaluated in the biomechanical rehearsal of resistance to the micro-traction. The glycerin has presented lower values in relation to the resistance test, showing, after 30 days, only 24.58% of the present power in the fresh bone, and by 180 days, 1.76%. The samples submitted to autoclavation also showed low values by the end of the experiment, while they remained with just 12.31% of the power present in the fresh bone. The bones preserved in homologous plasma, Dakin liquid and the ones cryopreserved showed the best levels of resistance at the end of the experiment, remaining, respectively with 82.47, 70.34 and 66.72% of the maximum power, while compared with the resistance of the fresh bones. The conclusion is that the choice of methodology and time of preservation interfered directly in the biomechanics of the cortical bones, promoting decrease of the resistance capacity to the traction along the period of preservation.

• Bone graft bone preservation bone resistance bone micro-traction rabbits

Abstract in Portuguese:

ABSTRACT.- Sampaio R.S., Lacerda M.S., Oliveira P.C.L., Paneto J.C.C., Bittar E.R., Borges G.A., Camacho G.M.M. & Braga E.M. 2009. [Variation of the resistance force to the micro-traction of fragments of cortical bones preserved in several means and fresh: Experimental study in rabbits.] Variação da força de resistência à micro-tração de fragmentos de ossos corticais preservados e a fresco: estudo experimental em coelhos. Pesquisa Veterinária Brasileira 29(4):345-352. Instituto de Estudos Avançados em Veterinária “José Caetano Borges”, Universidade de Uberaba, Av. Afrânio Azevedo 2140, Bairro Olinda, Uberaba, MG 38020-450, Brazil. E-mail: relisampa@terra.com.br Due to the increasing use of cortical bone allografts in orthopedic surgeries, de knowledge of its biomechanics characteristics during preservation time is needed. The present study consisted in the analyses of the resistance power to the micro-traction of samples of rabbit cortical bones preserved in several means for up to 180 days and fresh. The results showed that the resistance and the preservation time presented an inversely proportional relation, meaning that, the longer the time of preservation, the shorter the physical resistance evaluated in the biomechanical rehearsal of resistance to the micro-traction. The glycerin has presented lower values in relation to the resistance test, showing, after 30 days, only 24.58% of the present power in the fresh bone, and by 180 days, 1.76%. The samples submitted to autoclavation also showed low values by the end of the experiment, while they remained with just 12.31% of the power present in the fresh bone. The bones preserved in homologous plasma, Dakin liquid and the ones cryopreserved showed the best levels of resistance at the end of the experiment, remaining, respectively with 82.47, 70.34 and 66.72% of the maximum power, while compared with the resistance of the fresh bones. The conclusion is that the choice of methodology and time of preservation interfered directly in the biomechanics of the cortical bones, promoting decrease of the resistance capacity to the traction along the period of preservation.

Abstract in English:

ABSTRACT.- Mendes H.M.F., Faleiros R.R., Vasconcelos A.C., Alves G.E.S. & Moore R.M. 2009. [Apoptosis in equine small colon subjected to experimental ischemia and reperfusion.] Apoptose no cólon menor eqüino submetido à isquemia e reperfusão experimentais. Pesquisa Veterinária Brasileira 29(3):198-204. Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, Pampulha, Belo Horizonte, MG 31270-901, Brazil. E-mail: faleiros@ufmg.br Intestinal ischemia and reperfusion are important factors for mortality in horses. The objective of this study was to detect and to quantify apoptosis in the mucosa of equine small colon in a model of ischemia and reperfusion. The small colon was surgically exposed in twelve horses, and two intestinal segments were demarcated and subjected to 90 (SI) or 180 (SII) minutes of complete arteriovenous ischemia. Intestinal samples were collected before ischemia (control), at its end and after 90 and 180 minutes of reperfusion. Samples were histological processed and stained by hematoxylin and eosin (SI and SII) and by the technique of TUNEL (SI). Digitized histological images were analyzed morphometrically to detect apoptotic cells and to determine the apoptotic index (AI). After 90 or 180 minutes of arteriovenous ischemia, an increase in apoptotic cells was verified when compared with the control group, although no difference could be detected between the different periods of ischemia (P<0.05). After the first 90 minutes of reperfusion, a decrease in AI occurred, similar in both segments, possibly due to lack of energy source promoted by ischemia. AI was maximized after 180 minutes of reperfusion (sample harvested only in SI) (P<0.05). In conclusion, apoptosis is an important cause of cellular mucosal death in equine small colon ischemic obstruction, occurring early in ischemia, and later (after 90 minutes) in the reperfusion period.

• Horse small colon apoptosis ischemia and reperfusion

Abstract in Portuguese:

ABSTRACT.- Mendes H.M.F., Faleiros R.R., Vasconcelos A.C., Alves G.E.S. & Moore R.M. 2009. [Apoptosis in equine small colon subjected to experimental ischemia and reperfusion.] Apoptose no cólon menor eqüino submetido à isquemia e reperfusão experimentais. Pesquisa Veterinária Brasileira 29(3):198-204. Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, Pampulha, Belo Horizonte, MG 31270-901, Brazil. E-mail: faleiros@ufmg.br Intestinal ischemia and reperfusion are important factors for mortality in horses. The objective of this study was to detect and to quantify apoptosis in the mucosa of equine small colon in a model of ischemia and reperfusion. The small colon was surgically exposed in twelve horses, and two intestinal segments were demarcated and subjected to 90 (SI) or 180 (SII) minutes of complete arteriovenous ischemia. Intestinal samples were collected before ischemia (control), at its end and after 90 and 180 minutes of reperfusion. Samples were histological processed and stained by hematoxylin and eosin (SI and SII) and by the technique of TUNEL (SI). Digitized histological images were analyzed morphometrically to detect apoptotic cells and to determine the apoptotic index (AI). After 90 or 180 minutes of arteriovenous ischemia, an increase in apoptotic cells was verified when compared with the control group, although no difference could be detected between the different periods of ischemia (P<0.05). After the first 90 minutes of reperfusion, a decrease in AI occurred, similar in both segments, possibly due to lack of energy source promoted by ischemia. AI was maximized after 180 minutes of reperfusion (sample harvested only in SI) (P<0.05). In conclusion, apoptosis is an important cause of cellular mucosal death in equine small colon ischemic obstruction, occurring early in ischemia, and later (after 90 minutes) in the reperfusion period.

Abstract in English:

ABSTRACT.- Bezerra Jr P.S., Santos A.S., Bandarra P.M., Pedroso P.M.O., Pavarini, S.P., Spanamberg A., Ferreiro L. & Driemeier D. 2009. [Experimental poisoning by Aspergillus clavatus in sheep.] Intoxicação experimental por Aspergillus clavatus em ovinos. Pesquisa Veterinária Brasileira 29(3):205-210. Setor de Patologia Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br This paper describes the experimental reproduction of a neurological condition in sheep by the administration of a beer by-product contaminated with Aspergillus clavatus. Samples of this by-product, in which pure cultures of A. clavatus grew, originated from two farms where outbreaks of A. clavatus poisoning in cattle had occurred. The onset of symptomatology was 2 to 6 days after dosage with the contaminated beer by-product or pure A. clavatus culture. The clinical course lasted from one and a half to 12 days. Clinical signs were predominantly of locomotor and respiratory nature and included muscle tremors, hyperesthesia, and progressive tachypnea, rigidity of the pelvic limbs, posterior weakness, and recumbency. One sheep also showed occasional knuckling of fetlocks of the hind limbs. Gait abnormalities and tremors were more pronounced after exercise. In 6 of 7 sheep, appetite and dypsia were maintained until close to death or euthanasia. The main histological findings consisted of chromatolytic neuronal degeneration and necrosis in selected nuclei of the brain stem, the ventral horn of the spinal cord and the spinal, trigeminal, stellate and celiac ganglions. Three sheep also presented slight degenerative and necrotic changes in muscles of the pelvic and thoracic limbs.

• Aspergillus clavatus sheep beer by-product poisoning neuronal chromatolysis

Abstract in Portuguese:

ABSTRACT.- Bezerra Jr P.S., Santos A.S., Bandarra P.M., Pedroso P.M.O., Pavarini, S.P., Spanamberg A., Ferreiro L. & Driemeier D. 2009. [Experimental poisoning by Aspergillus clavatus in sheep.] Intoxicação experimental por Aspergillus clavatus em ovinos. Pesquisa Veterinária Brasileira 29(3):205-210. Setor de Patologia Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br This paper describes the experimental reproduction of a neurological condition in sheep by the administration of a beer by-product contaminated with Aspergillus clavatus. Samples of this by-product, in which pure cultures of A. clavatus grew, originated from two farms where outbreaks of A. clavatus poisoning in cattle had occurred. The onset of symptomatology was 2 to 6 days after dosage with the contaminated beer by-product or pure A. clavatus culture. The clinical course lasted from one and a half to 12 days. Clinical signs were predominantly of locomotor and respiratory nature and included muscle tremors, hyperesthesia, and progressive tachypnea, rigidity of the pelvic limbs, posterior weakness, and recumbency. One sheep also showed occasional knuckling of fetlocks of the hind limbs. Gait abnormalities and tremors were more pronounced after exercise. In 6 of 7 sheep, appetite and dypsia were maintained until close to death or euthanasia. The main histological findings consisted of chromatolytic neuronal degeneration and necrosis in selected nuclei of the brain stem, the ventral horn of the spinal cord and the spinal, trigeminal, stellate and celiac ganglions. Three sheep also presented slight degenerative and necrotic changes in muscles of the pelvic and thoracic limbs.