PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Grecco F.B., Schild A.L., Soares M.P., Marcolongo-Pereira C., Estima-Silva P. & Sallis E.S.V. 2010. [Epidemiological aspects and hepatic lesions pattern in 35 outbreaks of Senecio spp. poisoning in cattle in southern Brazil.] Aspectos epidemiológicos e padrões de lesões hepáticas em 35 surtos de intoxicação por Senecio spp. em bovinos no sul do Rio Grande do Sul. Pesquisa Veterinária Brasileira 30(5):389-397. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The study aimed to characterize morphological patterns of 59 liver samples of Senecio spp. poisoned cattle from 35 outbreaks, observed in southern Rio Grande do Sul, Brazil, from 2000 to 2009. The lesions were associated with epidemiological changes during these years. The climate changes concerning accumulated rain and mean temperature during the different seasons were analyzed. The macroscopic and histological lesions were classified into 6 different patterns. The macroscopic classification was made according to capsular pattern, hepatic cut surface discoloration, and the presence of nodules. The histological classification was based on the distribution of fibrosis, the amount of megalocytes in 10 high magnification fields, and on bile duct proliferation. Pattern 1 was characterized by a whitish liver, diffuse fibrosis, severe bile duct proliferation, and discrete megalocytosis; pattern 2 was characterized by nodules consisting of groups of hepatocytes surrounded by fibrosis, severe bile duct proliferation, and discrete to mild megalocytosis; pattern 3 was characterized by a macro-nodular aspect to the cut surface with hepatic lobules surrounded by a thin septa of fibrous tissue, severe bile duct proliferation, and mild megalocytosis; pattern 4 was characterized by a non-nodular surface with marble aspect, mild to severe bile duct proliferation, and megalocytosis; pattern 5 was characterized by a non-nodular surface and bridging or diffuse fibrosis, mild megalocytosis, and severe bile duct proliferation; and pattern 6 was characterized by a non-nodular surface, severe megalocytosis, discrete bile duct proliferation, and incipient fibrosis of the portal system, central vein or among hepatocyte cords. The results of macroscopic and histological liver analysis showed that patterns 1, 2 and 4 were the most frequently observed. The results of this study demonstrated that the macroscopic lesion observed in Senecio poisoned cattle is variable. Histologically this variation is related to the amount and distribution of fibrosis, megalocytosis and bile duct proliferation observed in each liver. Age of the cattle, evolution period of poisoning and clinical signs did not interfere on the pattern of lesions observed. On the other hand, climatic conditions probably had influence on increased disease prevalence due to major availability of Senecio spp. plants.

• Senecio spp. plant poisoning poisonous plants plantas tóxicas intoxicação por plantas

Abstract in Portuguese:

RESUMO.- Grecco F.B., Schild A.L., Soares M.P., Marcolongo-Pereira C., Estima-Silva P. & Sallis E.S.V. 2010. [Epidemiological aspects and hepatic lesions pattern in 35 outbreaks of Senecio spp. poisoning in cattle in southern Brazil.] Aspectos epidemiológicos e padrões de lesões hepáticas em 35 surtos de intoxicação por Senecio spp. em bovinos no sul do Rio Grande do Sul. Pesquisa Veterinária Brasileira 30(5):389-397. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br O presente estudo teve como objetivo caracterizar os diferentes padrões morfológicos hepáticos em 59 fígados de bovinos intoxicados por Senecio spp. provenientes de 35 surtos observados na área de influência do Laboratório Regional de Diagnóstico da Faculdade de Veterinária da Universidade Federal de Pelotas (LRD) de 2000-2009, dos quais havia registro fotográfico das lesões macroscópicas, fazendo uma relação com as variações epidemiológicas observadas no período. Foram analisadas as variações climáticas referentes à precipitação pluviométrica e temperatura média nas diferentes estações do ano ocorridas neste intervalo de tempo. As alterações hepáticas macro e microscópicas foram agrupadas em padrões morfológicos semelhantes. Foi considerada como critérios de classificação macroscópica a coloração das superfícies capsular e de corte e a presença ou não de nódulos; e como critérios para a classificação histológica a quantidade e distribuição da fibrose, o número de megalócitos por campo de maior aumento, o grau estimado de proliferação de ductos biliares e a presença de hepatócitos vacuolizados. O Padrão 1 caracterizou-se por fígado esbranquiçado, fibrose difusa, acentuada proliferação de células de ductos biliares e megalocitose discreta; o Padrão 2 por presença de nódulos correspondentes a grupos de hepatócitos ou lóbulos hepáticos circundados por tecido conjuntivo fibroso, acentuada proliferação de células de ductos biliares e megalocitose de discreta a moderada; o Padrão 3 por superfície de corte com aspecto macronodular correspondente a lóbulos hepáticos circundados por delgado cordão de tecido conjuntivo, acentuada proliferação de ductos biliares e megalocitose moderada; o Padrão 4 por superfície sem nodulações e com aspecto marmorizado e histologicamente por fibrose em ponte, megalocitose e proliferação de células de ductos de moderadas a acentuadas; o Padrão 5 por superfície sem nodulações e microscopicamente por fibrose em ponte a difusa, megalocitose moderada e acentuada proliferação de células de ductos; e, o Padrão 6 por superfície sem nodulações e microscopicamente por megalocitose acentuada, proliferação de ductos discreta e fibrose em estágio inicial localizada nos espaços porta e veia centrolobular ou como colágeno imaturo entre os cordões de hepatócitos. Os resultados da análise macroscópica e histológica dos fígados dos bovinos demonstraram que os Padrões 1, 2 e 4 foram os mais frequentemente encontrados. Os resultados deste trabalho demonstram que a lesão hepática macroscópica que ocorre em bovinos intoxicados por Senecio spp. é variável e que histologicamente esta variação está relacionada à distribuição e a quantidade da fibrose, à quantidade de megalócitos e à proliferação biliar observadas em cada fígado. A idade dos animais, o tempo de evolução da intoxicação e os sinais clínicos não interferem nos padrões de lesões hepáticas encontradas. Por outro lado, as condições climáticas provavelmente tiveram influência no aumento da freqüência da doença devido ao aumento da disponibilidade da planta.

Abstract in English:

ABSTRACT.- Pierezan F., Oliveira Filho J.C., Carmo P.M., Lucena R.B., Rissi, D.R., Togni M. & Barros C.S.L. 2010. [Outbreak of aflatoxicosis in calves in southern Brazil.] Surto de aflatoxicose em bezerros no Rio Grande do Sul. Pesquisa Veterinária Brasileira 30(5):418-422. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br An outbreak of chronic aflatoxicosis is reported in dairy calves. Forty 4-month-old male Holstein calves of approximately 100kg were kept in individual cages of 1.5 x 1.5m and were fed a ration constituted by alfalfa hay, broken corn and milk substitute. Six calves (15%) died after presenting a disease characterized by general unthriftiness, diarrhea, rough hair coats, abdominal pain, prolapsed rectum, grinding of teeth, and lying down and rolling. The clinical course, as observed by the owners, was 2-3 days; however many calves in this lot that did not die, remained underdeveloped. Three calves were necropsied. Necropsy findings included firm, light tan livers and marked hydrothorax, ascites and edema of the mesentery, mesocolon and of the mucosal folds of the abomasum. Main histopathological changes were restricted to the liver and consisted of fibrosis, moderate megalocytosis, biliary duct hyperplasia and veno-occlusive disease. The search for Senecio spp. contamination in the alfalfa hay resulted negative. The analysis by thin layer chromatography of the corn fed to calves revealed 5,136 ppb of aflatoxin B1. A diagnosis of aflatoxicosis was made based on the characteristic clinical signs and pathology, on the absence of Senecio spp. in the food and on the presence of high levels of aflatoxin in the corn fed to the calves.

• Mycotoxicosis aflatoxicosis micotoxicose aflatoxicose

Abstract in Portuguese:

RESUMO.- Pierezan F., Oliveira Filho J.C., Carmo P.M., Lucena R.B., Rissi, D.R., Togni M. & Barros C.S.L. 2010. [Outbreak of aflatoxicosis in calves in southern Brazil.] Surto de aflatoxicose em bezerros no Rio Grande do Sul. Pesquisa Veterinária Brasileira 30(5):418-422. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Um surto de aflatoxicose crônica é relatado em bezerros de raça leiteira. Quarenta bezerros holandeses machos de quatro meses de idade e aproximadamente 100kg eram mantidos em gaiolas individuais de 1,5 x 1,5m e alimentados com uma ração constituída por feno de alfafa, milho quebrado e substituto de leite. Seis bezerros (15%) morreram após apresentar uma doença caracterizada por mau desenvolvimento geral, diarreia, pelagem áspera, dor abdominal, tenesmo, prolapso de reto e bruxismo. Alguns bezerros “deitavam e rolavam” no chão da gaiola. A duração do curso clínico, segundo observado pelos proprietários, foi de 2-3 dias; muitos terneiros desse lote que não morreram permaneceram pouco desenvolvidos. Três bezerros foram necropsiados. Os achados de necropsia incluíam fígado firme e castanho-claro, marcados hidrotórax e ascite, e edema do mesentério, mesocólon e das dobras da mucosa do abomaso. Os principais achados histopatológicos estavam restritos ao fígado e consistiam de fibrose, moderada megalocitose, hiperplasia de ductos biliares e lesão veno-oclusiva. A procura por contaminação de Senecio spp. no feno de alfafa resultou negativa. A análise do milho do alimento dos bezerros por cromatografia de camada delgada revelou 5.136ppb de aflatoxina B1. O diagnóstico de aflatoxicose foi feito baseado nos sinais clínicos e patologia característicos, na ausência de Senecio spp. na alimentação dos terneiros e na presença de altos níveis de aflatoxina no milho da alimentação dos bezerros.

Abstract in English:

ABSTRACT.- Barbosa J.D., Dutra. M.D. Oliveira C.M.C., Silveira J.A.S., Albernaz. T.T. & Cerqueira V.D. 2009. [Outbreak of tetanus in bufalloes (Buballus bubalis) in Pará, Brazil.] Surto de tétano em búfalos (Buballus bubalis) no Estado do Pará. Pesquisa Veterinária Brasileira 29(3):263-266. Central de Diagnóstico Veterinário, Universidade Federal do Pará, Rua Maximino Porpino da Silva 1000, Pirapora, Castanhal, PA 68743-080, Brazil. E-mail: diomedes@ufpa.br An outbreak of tetanus in Murrah buffaloes in Belém, state of Pará, Brazil, is described. The outbreak was observed in a flock of 250 buffaloes, 80 of which were vaccinated intra-muscularly in the croup against rabies. Four buffaloes fell ill 15 to 19 days after vaccination, one died after a clinical course of 2 days, one was submitted to euthanasia in extremis on the 7th day after the onset of symptoms, and two others recovered within 2 weeks after treatment with penicillin for 4 days and anti-tetanic serum. The first symptoms observed were prolapse of the third eyelid, especially when the animal was stimulated, followed by a rigid walk, as difficulty in inflexing the members and lateral recumbence with the members extended, besides very open eyelids, sialorrhea, hyperexcitability, erect ears and slight lockjaw, and food accumulation in the oral cavity. At post-mortem examination was found a focus of yellowish pus in the croup muscles, where the vaccine had been applied. At histopathology no significant alterations in internal organs were observed. Based on the clinical picture, the epidemic data and absence of histological lesions, the diagnosis of tetanus was established. The infection was considered to be due to the use of dirty needles used during vaccination.

• Buffaloes tetanus Pará

Abstract in Portuguese:

ABSTRACT.- Barbosa J.D., Dutra. M.D. Oliveira C.M.C., Silveira J.A.S., Albernaz. T.T. & Cerqueira V.D. 2009. [Outbreak of tetanus in bufalloes (Buballus bubalis) in Pará, Brazil.] Surto de tétano em búfalos (Buballus bubalis) no Estado do Pará. Pesquisa Veterinária Brasileira 29(3):263-266. Central de Diagnóstico Veterinário, Universidade Federal do Pará, Rua Maximino Porpino da Silva 1000, Pirapora, Castanhal, PA 68743-080, Brazil. E-mail: diomedes@ufpa.br An outbreak of tetanus in Murrah buffaloes in Belém, state of Pará, Brazil, is described. The outbreak was observed in a flock of 250 buffaloes, 80 of which were vaccinated intra-muscularly in the croup against rabies. Four buffaloes fell ill 15 to 19 days after vaccination, one died after a clinical course of 2 days, one was submitted to euthanasia in extremis on the 7th day after the onset of symptoms, and two others recovered within 2 weeks after treatment with penicillin for 4 days and anti-tetanic serum. The first symptoms observed were prolapse of the third eyelid, especially when the animal was stimulated, followed by a rigid walk, as difficulty in inflexing the members and lateral recumbence with the members extended, besides very open eyelids, sialorrhea, hyperexcitability, erect ears and slight lockjaw, and food accumulation in the oral cavity. At post-mortem examination was found a focus of yellowish pus in the croup muscles, where the vaccine had been applied. At histopathology no significant alterations in internal organs were observed. Based on the clinical picture, the epidemic data and absence of histological lesions, the diagnosis of tetanus was established. The infection was considered to be due to the use of dirty needles used during vaccination.

Abstract in English:

ABSTRACT.- Gabriel A.L., Kommers G.D., Trost M.E., Barros C.S.L., Pereira D.B., Schwendler S.E. & Santurio J.M. 2008. [Outbreak of cutaneous pythiosis in cattle.] Surto de pitiose cutânea em bovinos. Pesquisa Veterinária Brasileira 28(12):583-587. Departamento de Patologia, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: glaukommers@yahoo.com Seventy-six young mixed breed cattle of both sexes, presented multifocal ulcerated nodular cutaneous lesions localized in the medial and lateral aspects of fore and hindlimbs, ventral neck, sternum, and tail. The disease occurred during summer and lesions were observed on areas of the body which were in contact with water of irrigation channels for long periods. Histologically, there were multiple granulomas and pyogranulomas with few negative profiles of hyphae, which were better visualized throughout Grocott methenamine silver stain. Definitive etiologic diagnosis was based on immuno-histochemistry with anti-Pythium insidiosum polyclonal antibody. Additionally, an indirect ELISA test was performed. Bovine cutaneous pythiosis outbreaks are uncommon and, particularly as occurred in the cattle of this report, all affected animals had spontaneous healing within two to three weeks.

• Pythiosis Pythium insidiosum diseases of cattle immunohistochemistry ELISA test pathology

Abstract in Portuguese:

ABSTRACT.- Gabriel A.L., Kommers G.D., Trost M.E., Barros C.S.L., Pereira D.B., Schwendler S.E. & Santurio J.M. 2008. [Outbreak of cutaneous pythiosis in cattle.] Surto de pitiose cutânea em bovinos. Pesquisa Veterinária Brasileira 28(12):583-587. Departamento de Patologia, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: glaukommers@yahoo.com Seventy-six young mixed breed cattle of both sexes, presented multifocal ulcerated nodular cutaneous lesions localized in the medial and lateral aspects of fore and hindlimbs, ventral neck, sternum, and tail. The disease occurred during summer and lesions were observed on areas of the body which were in contact with water of irrigation channels for long periods. Histologically, there were multiple granulomas and pyogranulomas with few negative profiles of hyphae, which were better visualized throughout Grocott methenamine silver stain. Definitive etiologic diagnosis was based on immuno-histochemistry with anti-Pythium insidiosum polyclonal antibody. Additionally, an indirect ELISA test was performed. Bovine cutaneous pythiosis outbreaks are uncommon and, particularly as occurred in the cattle of this report, all affected animals had spontaneous healing within two to three weeks.

Abstract in English:

Abstract.- Pavarini S.P., Bezerra Junior P.S., Santos A.S., Pescador C.A. & Driemeier D. 2008. [Clinic pathological features during a winter dysentery outbreak in cattle in Rio Grande do Sul.] Achados clínico patológicos durante um surto de disenteria de inverno em bovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(12):611- 616. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br The report describes a winter dysentery outbreak that affected 10 dairy cows from a ranch located in the county of Viamão, Rio Grande do Sul. The most significant clinical sign was profuse and watery diarrhea, which ranged from a greenish to a brownish coloration and from occasional blood streaks with mucus to a bloody diarrhea. Most cases persisted for 5 days and also included depression, drastic decrease in milk production and in food consumption. Only one of the affected animals died. The necropsy revealed pale mucosa and sanguineous content with high quantity of blood clots, particularly within the spiral colon, and petechiae on the colonic mucosa. Histopathological lesions were predominant in the spiral colon, and consisted of a high number of dilated crypts without epithelium or with the replacement of a pavement epithelium with occasional immature cuboidal cells, which sometimes showed enlarged nucleus and proeminent nucleolus. Some crypts were filled with epithelial desquamation and polymorphnuclear cells. Bovine coronavirus (8F2) monoclonal antibody was used for immunohistochemistry on sections of the spiral colon that showed positive reactions in the cytoplasm of the infected crypt epithelium, sloughed necrotic cells, and within macrophages in the lamina propria of both.

• Winter dysentery diarrhea spiral colon bovine coronavirus

Abstract in Portuguese:

Abstract.- Pavarini S.P., Bezerra Junior P.S., Santos A.S., Pescador C.A. & Driemeier D. 2008. [Clinic pathological features during a winter dysentery outbreak in cattle in Rio Grande do Sul.] Achados clínico patológicos durante um surto de disenteria de inverno em bovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(12):611- 616. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br The report describes a winter dysentery outbreak that affected 10 dairy cows from a ranch located in the county of Viamão, Rio Grande do Sul. The most significant clinical sign was profuse and watery diarrhea, which ranged from a greenish to a brownish coloration and from occasional blood streaks with mucus to a bloody diarrhea. Most cases persisted for 5 days and also included depression, drastic decrease in milk production and in food consumption. Only one of the affected animals died. The necropsy revealed pale mucosa and sanguineous content with high quantity of blood clots, particularly within the spiral colon, and petechiae on the colonic mucosa. Histopathological lesions were predominant in the spiral colon, and consisted of a high number of dilated crypts without epithelium or with the replacement of a pavement epithelium with occasional immature cuboidal cells, which sometimes showed enlarged nucleus and proeminent nucleolus. Some crypts were filled with epithelial desquamation and polymorphnuclear cells. Bovine coronavirus (8F2) monoclonal antibody was used for immunohistochemistry on sections of the spiral colon that showed positive reactions in the cytoplasm of the infected crypt epithelium, sloughed necrotic cells, and within macrophages in the lamina propria of both.

Abstract in English:

ABSTRACT.- França T.N., Ribeiro C.T., Bezerra P.S., Döbereiner J., Cerqueira V.D. & Peixoto P.V. 2008. [Outbreaks of Proliferative Haemorrhagic Enteropathy (Lawsonia intracelullaris) in swine in Rio de Janeiro state.] Surtos de Enteropatia Proliferativa Hemorrágica (Lawsonia intracelullaris) em suínos no Estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 28(3):174-182. Centro de Ciências Biológicas e da Saúde, Faculdade de Medicina Veterinária, Universidade Estácio de Sá, Rio de Janeiro, RJ 22783-320, Brazil. E-mail: ticianafranca@terra.com.br Outbreaks of infection of swine with Lawsonia intracelullaris in the state of Rio de Janeiro are described. The symptomathology was characterized by bloody diarrhea with peracute course. Postmortem findings were pale organs and tissues, reticulate aspect of the ileum with its mucosa moderately thickened nad contained large amounts of partially coagulated blood. Histopathological examination revealed hyperplastic epithelial cell proliferation of the Lieberkühn crypts, sometimes associated with inflammatory and necrotic alterations. Immunohistochemistry demonstrated the presence of large amounts of bacteria in the cytoplasm of the cryptal epithelial cells. L. intracellularis was also seen by ultramicroscopic examination. These outbreaks occurred in 1987 and this is the first report of the disease in the state of Rio de Janeiro.

• Lawsonia intracellularis Proliferative Haemorrhagic Enteropathy swine Rio de Janeiro

Abstract in Portuguese:

ABSTRACT.- França T.N., Ribeiro C.T., Bezerra P.S., Döbereiner J., Cerqueira V.D. & Peixoto P.V. 2008. [Outbreaks of Proliferative Haemorrhagic Enteropathy (Lawsonia intracelullaris) in swine in Rio de Janeiro state.] Surtos de Enteropatia Proliferativa Hemorrágica (Lawsonia intracelullaris) em suínos no Estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 28(3):174-182. Centro de Ciências Biológicas e da Saúde, Faculdade de Medicina Veterinária, Universidade Estácio de Sá, Rio de Janeiro, RJ 22783-320, Brazil. E-mail: ticianafranca@terra.com.br Outbreaks of infection of swine with Lawsonia intracelullaris in the state of Rio de Janeiro are described. The symptomathology was characterized by bloody diarrhea with peracute course. Postmortem findings were pale organs and tissues, reticulate aspect of the ileum with its mucosa moderately thickened nad contained large amounts of partially coagulated blood. Histopathological examination revealed hyperplastic epithelial cell proliferation of the Lieberkühn crypts, sometimes associated with inflammatory and necrotic alterations. Immunohistochemistry demonstrated the presence of large amounts of bacteria in the cytoplasm of the cryptal epithelial cells. L. intracellularis was also seen by ultramicroscopic examination. These outbreaks occurred in 1987 and this is the first report of the disease in the state of Rio de Janeiro.

Abstract in English:

Rodrigues A., Fighera R.A., Souza T.M., Schild A.L., Soares M.P., Milano J. & Barros C.S.L. 2005. [Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects.] Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos. Pesquisa Veterinária Brasileira 25(4):239-249. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of trypanosomiasis by Trypanosoma evansi were diagnosed in horses in the state of Rio Grande do Sul, Brazil, between 2003 and 2004. In one stud farm (Farm A) with 125 horses, 52 died. Additionally, around 80 mares were sent to Farm A to be bred. Of those, 66 became ill and 56 died after being returned to their farms of origin. Twenty one horses clinically affected by the disease were observed. Clinical signs included loss of weight (despite voracious appetite), lethargy, incoordination and instability of hindlimbs, atrophy of the large muscles of the hindlimbs, muscle weakness and paleness of mucosae. Specimens of T. evansi were detected in the blood drawn from four affected horses. Normocytic normochromic anemia with PCVs ranging from 15 to 31%, leucocytosis due to lymphocytosis associated to large atypical lymphocytes was observed in several affected horses. High levels of antibodies against T. evansi were detected in the serum of six horses from Farm A. Eight horses presented encephalic neurological signs such as circling, ataxia, blindness, excitation, falls, listlessness, proprioception deficits and head tilt. One horse assumed a “dog-seating position”. Necropsy findings included muscle atrophy, enlargement and lymphoid hyperplasia of the spleen and lymphnodes, edema and softening of the white and grey matter of the brain. Histologically, an overwhelming necrotizing panencephalitis was observed in the seven horses with encephalic signs. This panencephalitis was characterized by marked edema, demyelination and necrosis and perivascular infiltrates of 6-10 layers of lymphocytes and plasm cells affecting both the white and gray matter. Several plasm cells in the inflammatory infiltrate contained numerous eosinophilic globules in their cytoplasm (Mott cells). Similar histological lesions were observed in the spinal cord of the horse with the “dog-seating position”. The brains of five horses with the encephalic signs were submitted to immunohistochemistry stain by the streptavidin-biotin technique. In all of those five brains moderate to abundant specimens of T. evansi in the perivascular spaces and neuropile were marked by the specific antibody. Epidemiological, clinical, hematological, and pathological aspects of equine trypanosomiasis caused by T. evansi are discussed.

• Trypanosomiasis Trypanosoma evansi infectious diseases encephalitis hematology pathology diseases of horses.

Abstract in Portuguese:

Rodrigues A., Fighera R.A., Souza T.M., Schild A.L., Soares M.P., Milano J. & Barros C.S.L. 2005. [Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects.] Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos. Pesquisa Veterinária Brasileira 25(4):239-249. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of trypanosomiasis by Trypanosoma evansi were diagnosed in horses in the state of Rio Grande do Sul, Brazil, between 2003 and 2004. In one stud farm (Farm A) with 125 horses, 52 died. Additionally, around 80 mares were sent to Farm A to be bred. Of those, 66 became ill and 56 died after being returned to their farms of origin. Twenty one horses clinically affected by the disease were observed. Clinical signs included loss of weight (despite voracious appetite), lethargy, incoordination and instability of hindlimbs, atrophy of the large muscles of the hindlimbs, muscle weakness and paleness of mucosae. Specimens of T. evansi were detected in the blood drawn from four affected horses. Normocytic normochromic anemia with PCVs ranging from 15 to 31%, leucocytosis due to lymphocytosis associated to large atypical lymphocytes was observed in several affected horses. High levels of antibodies against T. evansi were detected in the serum of six horses from Farm A. Eight horses presented encephalic neurological signs such as circling, ataxia, blindness, excitation, falls, listlessness, proprioception deficits and head tilt. One horse assumed a “dog-seating position”. Necropsy findings included muscle atrophy, enlargement and lymphoid hyperplasia of the spleen and lymphnodes, edema and softening of the white and grey matter of the brain. Histologically, an overwhelming necrotizing panencephalitis was observed in the seven horses with encephalic signs. This panencephalitis was characterized by marked edema, demyelination and necrosis and perivascular infiltrates of 6-10 layers of lymphocytes and plasm cells affecting both the white and gray matter. Several plasm cells in the inflammatory infiltrate contained numerous eosinophilic globules in their cytoplasm (Mott cells). Similar histological lesions were observed in the spinal cord of the horse with the “dog-seating position”. The brains of five horses with the encephalic signs were submitted to immunohistochemistry stain by the streptavidin-biotin technique. In all of those five brains moderate to abundant specimens of T. evansi in the perivascular spaces and neuropile were marked by the specific antibody. Epidemiological, clinical, hematological, and pathological aspects of equine trypanosomiasis caused by T. evansi are discussed.

Abstract in English:

Brito M.F., Seixas J.N., Jabour F.F., Andrade G.B., Cunha B.R.M., França T.N. & Peixoto P.V. 2005. [About an outbreak of cumarin poisoning in cattle.] Sobre um surto de envenenamento por derivado cumarínico em bovinos. Pesquisa Veterinária Brasileira 25(3):143-149. Depto Epidemiologia e Saúde Pública, Instituto de Veterinária, UFRRJ, Seropédica, RJ 23890-000, Brazil. E-mail: marilene@ufrrj.br An outbreak of cumarin poisoning which occurred in feedlot cattle in the county of Seropédica, Rio de Janeiro, is described. Three from 43 animal died. The main manifestations included bloody diarrhea, apathy, anorexia, sialorrhoe, incoordenation and dyspnoe. At post-mortem examinations there were mainly hemorrhages of varies forms and intensity in several organs, which also were seen at histopathological examination. Analysis for cumarin derivates of rumen, reticulum, omasum and abomasum contents, of liver and kidney samples, as well as of food collected from the trough, resulted positive for cumarin compounds which included warfarin, bromadiolone and brodifacoum. Feeding experiments with food stored at the property resulted negative. An intentional or accidental act could not be excluded. Animals that did not feed from the same trough did not get sick.

• umarin poisoning cattle.

Abstract in Portuguese:

Brito M.F., Seixas J.N., Jabour F.F., Andrade G.B., Cunha B.R.M., França T.N. & Peixoto P.V. 2005. [About an outbreak of cumarin poisoning in cattle.] Sobre um surto de envenenamento por derivado cumarínico em bovinos. Pesquisa Veterinária Brasileira 25(3):143-149. Depto Epidemiologia e Saúde Pública, Instituto de Veterinária, UFRRJ, Seropédica, RJ 23890-000, Brazil. E-mail: marilene@ufrrj.br An outbreak of cumarin poisoning which occurred in feedlot cattle in the county of Seropédica, Rio de Janeiro, is described. Three from 43 animal died. The main manifestations included bloody diarrhea, apathy, anorexia, sialorrhoe, incoordenation and dyspnoe. At post-mortem examinations there were mainly hemorrhages of varies forms and intensity in several organs, which also were seen at histopathological examination. Analysis for cumarin derivates of rumen, reticulum, omasum and abomasum contents, of liver and kidney samples, as well as of food collected from the trough, resulted positive for cumarin compounds which included warfarin, bromadiolone and brodifacoum. Feeding experiments with food stored at the property resulted negative. An intentional or accidental act could not be excluded. Animals that did not feed from the same trough did not get sick.

Abstract in English:

França T.N., Peixoto P.V., Brito M.F., Driemeier D., Mores N. & Zanella J. 2005. [Outbreak of Circovirosis (Porcine Postweaning Multisystemic Wasting Syndrome) in the state of Rio de Janeiro, Brazil.] Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 25(1):39-53. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The first outbreak of Postweaning Multisystemic Wasting Syndrome (PMWS) in swine, which occurred in southeastern Brazil, in the state of Rio de Janeiro, is described. The disease, which affects mainly weaned about 4 month-old pigs, caused the death of at least 14 animals. The property, where the outbreak occurred, had inadequate sanitary and management conditions. Clinically the disease was characterized by wasting, poor development, cough, tachypnoea, dispnoea, diarrhoea, ataxia, tremors after stimulation, decubitus and convulsions. The course of the disease was acute or subacute. The most important post-mortem findings were enlarged lymphnodes, non-collapsed lungs, with consolidated areas mainly in the cranial lobes. Histological lesions consisted mainly of lymphohistiocytic infiltration with multinucleate giant cells in lymph nodes, spleen, Peyer’s patches, kidney, lung and liver, depletion or lymphoid hyperplasia, as well as lymphohistiocytic interstitial pneumonia and areas of secondary bronchopneumonia. The diagnosis was established through observations of the symptoms and typical lesions, and was confirmed by immunohistochemical examination and PCR. The objective of this study was to characterize the epidemiological, clinical and pathological aspects of the outbreak of PMWS, because of the severe direct or indirect economical losses caused by the disease to the world pig industry.

• Postweaning multisystemic wasting syndrome porcine circovirus type 2 pathology immunohistochemistry PCR.

Abstract in Portuguese:

França T.N., Peixoto P.V., Brito M.F., Driemeier D., Mores N. & Zanella J. 2005. [Outbreak of Circovirosis (Porcine Postweaning Multisystemic Wasting Syndrome) in the state of Rio de Janeiro, Brazil.] Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 25(1):39-53. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The first outbreak of Postweaning Multisystemic Wasting Syndrome (PMWS) in swine, which occurred in southeastern Brazil, in the state of Rio de Janeiro, is described. The disease, which affects mainly weaned about 4 month-old pigs, caused the death of at least 14 animals. The property, where the outbreak occurred, had inadequate sanitary and management conditions. Clinically the disease was characterized by wasting, poor development, cough, tachypnoea, dispnoea, diarrhoea, ataxia, tremors after stimulation, decubitus and convulsions. The course of the disease was acute or subacute. The most important post-mortem findings were enlarged lymphnodes, non-collapsed lungs, with consolidated areas mainly in the cranial lobes. Histological lesions consisted mainly of lymphohistiocytic infiltration with multinucleate giant cells in lymph nodes, spleen, Peyer’s patches, kidney, lung and liver, depletion or lymphoid hyperplasia, as well as lymphohistiocytic interstitial pneumonia and areas of secondary bronchopneumonia. The diagnosis was established through observations of the symptoms and typical lesions, and was confirmed by immunohistochemical examination and PCR. The objective of this study was to characterize the epidemiological, clinical and pathological aspects of the outbreak of PMWS, because of the severe direct or indirect economical losses caused by the disease to the world pig industry.

Abstract in English:

Zlotowski P., Corrêa A. M. R., Rozza D. B., Driemeier D., Mallmann C. A. & Migliavacca F.A. 2004. [Swine aflatoxicosis outbreak in the state of Rio Grande do Sul, Brazil.] Surto de aflatoxicose em suínos no Estado do Rio Grande do Sul. Pesquisa Veterinária Brasileira 24(4):207-210. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veteri-nária, UFRGS, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br An outbreak of aflatoxicosis in a swine herd, which occurred in fall 2004 in the county of Sentinela do Sul, RS, is described. The corn, which contained the micotoxin and has been used to feed the animals, was produced and processed on the farm. Seven sows and 8 growing pigs died, and 2 cases of abortion were reported. The clinical signs observed were apathy, anorexia, icterus, yellowish urine stained with blood, and photosensitization. Gamma glutamyltransferase and total bilirubin were elevated in the 4 pigs on which post-mortem examination was done. The main macroscopic findings were generalized icterus, an orange-yellow liver, edema of the gall bladder wall and yellowish effusion in the abdominal and pericardial cavities. The most important microscopic changes were found in the liver and included tumefaction, degeneration and individual necrosis of the parenchyme, with ductal proliferation and cholestasis. The diagnosis was based on the clinical signs, macroscopic and histological findings and on the high levels of B1 aflatoxin found in the corn and ration.

• Mycotoxins aflatoxicosis hepatotoxicosis swine pathology.

Abstract in Portuguese:

Zlotowski P., Corrêa A. M. R., Rozza D. B., Driemeier D., Mallmann C. A. & Migliavacca F.A. 2004. [Swine aflatoxicosis outbreak in the state of Rio Grande do Sul, Brazil.] Surto de aflatoxicose em suínos no Estado do Rio Grande do Sul. Pesquisa Veterinária Brasileira 24(4):207-210. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veteri-nária, UFRGS, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br An outbreak of aflatoxicosis in a swine herd, which occurred in fall 2004 in the county of Sentinela do Sul, RS, is described. The corn, which contained the micotoxin and has been used to feed the animals, was produced and processed on the farm. Seven sows and 8 growing pigs died, and 2 cases of abortion were reported. The clinical signs observed were apathy, anorexia, icterus, yellowish urine stained with blood, and photosensitization. Gamma glutamyltransferase and total bilirubin were elevated in the 4 pigs on which post-mortem examination was done. The main macroscopic findings were generalized icterus, an orange-yellow liver, edema of the gall bladder wall and yellowish effusion in the abdominal and pericardial cavities. The most important microscopic changes were found in the liver and included tumefaction, degeneration and individual necrosis of the parenchyme, with ductal proliferation and cholestasis. The diagnosis was based on the clinical signs, macroscopic and histological findings and on the high levels of B1 aflatoxin found in the corn and ration.