PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Panziera W., Vielmo A., De Lorenzo C., Heck L.C., Pavarini S.P., Sonne L., Soares J.F. & Driemeier D. 2018. [Characterization of parasitic lesions of sheep observed at slaughter line.] Caracterização das lesões parasitárias de ovinos observadas na linha de abate. Pesquisa Veterinária Brasileira 38(8):1491-1504. Setor de Patologia Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, prédio 42505, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Considering the possibilities of mistaken diagnoses in identifying lesions at meat inspection this study was designed to provide data for a better-educated diagnosis by the meat inspectors through the gross and microscopic characterization of parasitic lesions observed in slaughtered sheep at the inspection line. One hundred and sixty-one samples of parasitic lesions were sampled from various organs of slaughtered sheep during two visits to a sheep abattoir located in the state of Rio Grande do Sul, Brazil. Lesions observed included hydatid cysts, cysticercosis due to Cysticercus ovis and to Cysticercus tenuicollis, sarcocystosis (morphology compatible with Sarcocystis gigantea), fasciolosis (Fasciola hepatica) and oesophagostomosis. Twenty-five point five percent of the 161 samples corresponded to hydatidosis and the hydatid cysts were observed predominantly in the lungs (46.3%) and liver (41.5%). On cut surface, the cysts had three different morphological patterns: viable unilocular cysts (34%); viable multivesicular cysts (31.7%); and degenerate (unilocular and multivesicular) hydatid cysts (34%). Cysticercosis by C. ovis (22.4%) was observed in the myocardium (63.9%), tongue (13.9%), masseter (11.1%), and diaphragm (11.1%). Morphologically the cysticerci were classified as viable, degenerated or mineralized. Lesions caused by S. Gigantea (19.2%) were observed in the muscle layer of the esophagus, tongue, and larynx. Grossly there were multiple white nodular structures that contained a fibrous capsule with the lumen filled by translucent and gelatinous material. Cysticercosis by C. tenuicollis accounted for 18.6% of observed parasitic lesions; the cysts adhered to the omentum, mesentery, liver capsule, and serosal surface of gall bladder; grossly the cysts were classified as viable and degenerated. Viable cysts had translucent or slightly opaque walls and contained a single scolex. Degenerated cysts were white, firm and with a thick fibrous capsule and mineralized center. Lesions caused by F. hepatica accounted for 7.4% of the cases and were grossly characterized by variable fibrous thickening of bile ducts which occasionally contained the adult flukes in their lumina. In eight cases there were marked areas of necrosis in the hepatic parenchyma. Lesions caused Oesophagostomum spp. accounted for 6.8% of the observed parasitic cases and the changes were observed in all cases in the walls of the small and large intestine; in two cases mesenteric lymph nodes were also involved. In the intestines, lesions were characterized by firm well-circumscribed nodules prominent in the serosal surface and also invading the muscle layer. In the lymph nodes marked mineralization obliterated the nodal parenchyma. The correct identification of the various parasitic lesions found in the viscera of sheep in the abattoir inspection line it is important to dictate the proper destination of affected organs and carcasses. The lesions should be evaluated aiming to determine their infective capacity and to acquire knowledge about their more frequent anatomical sites.

• Diseases of sheep parasitic lesions abattoir survey public health pathology Doenças de ovinos lesões parasitárias pesquisa em abatedouro saúde pública patologia.

Abstract in Portuguese:

RESUMO.- Panziera W., Vielmo A., De Lorenzo C., Heck L.C., Pavarini S.P., Sonne L., Soares J.F. & Driemeier D. 2018. [Characterization of parasitic lesions of sheep observed at slaughter line.] Caracterização das lesões parasitárias de ovinos observadas na linha de abate. Pesquisa Veterinária Brasileira 38(8):1491-1504. Setor de Patologia Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, prédio 42505, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Considerando a possibilidade de erros na identificação das lesões e a necessidade de melhorar o diagnóstico, o objetivo desse trabalho foi caracterizar macroscopicamente e microscopicamente as principais lesões parasitárias observadas em ovinos na linha de abate. Os materiais foram colhidos durante duas visitas a um matadouro frigorífico de ovinos no estado do Rio Grande do Sul. Totalizaram-se 161 amostras com lesões parasitárias de ovinos em diferentes órgãos. As alterações observadas incluíam hidatidose, cisticercose por Cysticercus ovis, cisticercose por Cysticercus tenuicollis, sarcocistose (morfologia compatível com Sarcocystis gigantea), fasciolose (Fasciola hepatica) e esofagostomose. Das 161 amostras, 25,5% correspondiam a hidatidose, e os cistos hidáticos foram observados, predominantemente, nos pulmões (46,3%) e fígado (41,5%). Ao corte, os cistos demonstraram três padrões morfológicos: cistos uniloculares viáveis (34%); cistos multivesiculares viáveis (31,7%); e cistos hidáticos (uniloculares e multivesiculares) degenerados (34%). As lesões de cisticercose por C. ovis (22,4%) foram visualizadas no coração (63,9%), língua (13,9%), músculo masseter (11,1%) e diafragma (11,1%). Morfologicamente os cisticercos foram classificados em vivos (viáveis), degenerados e mineralizados. Lesões provocadas por S. gigantea (19,2%) estavam presentes na túnica muscular do esôfago, na língua e na laringe. Macroscopicamente, observaram‑se múltiplas estruturas nodulares brancas que continham uma cápsula fibrosa e lúmen preenchido por material gelatinoso translúcido. Cisticercose por C. tenuicollis representaram 18,6% das lesões. Os cistos foram observados aderidos no omento, no mesentério, na cápsula do fígado e na vesícula biliar. Morfologicamente os cistos foram classificados como vivos (viáveis) e degenerados. Os cistos vivos apresentavam a parede translúcida ou levemente opaca, contendo um escólex no seu interior. Os cistos degenerados eram brancacentos, firmes, com espessa cápsula fibrosa e centro mineralizado. Lesões provocadas por F. hepatica corresponderam a 7,4% dos casos. As lesões hepáticas caracterizavam-se macroscopicamente por espessamento variável dos ductos biliares por fibrose e ocasionalmente havia exemplares de F. hepatica no lúmen dos ductos. Em oito casos, observaram-se áreas de acentuada necrose do parênquima hepático. Lesões provocadas por Oesophagostomum spp. perfizeram 6,8% dos casos. As alterações foram observadas no intestino delgado e intestino grosso de todos os ovinos e em dois casos, havia também envolvimento dos linfonodos mesentéricos. Nos intestinos, as lesões caracterizavam-se por nódulos bem delimitados, salientes na serosa, firmes e que invadiam também a camada muscular. Nos linfonodos havia obliteração do parênquima nodal por acentuada mineralização. É extremamente importante a identificação morfológica das diferentes lesões parasitárias encontradas nas linhas de abate em frigoríficos de ovinos, para posterior destino correto das mesmas. As alterações devem ser avaliadas com o intuito principal de reconhecer a sua capacidade infecciosa. Além disso, é fundamental o conhecimento dos locais anatômicos mais comuns em que cada alteração geralmente costuma ocorrer.

Abstract in English:

ABSTRACT.- Rissi D.R., Pierezan F., Oliveira Filho J.C., Fighera R.A., Irigoyen L.F., Kommers G.D. & Barros C.S.L. 2010. [Diseases of sheep from central Rio Grande do Sul State, Brazil: 361 cases.] Doenças de ovinos da região Central do Rio Grande do Sul: 361 casos. Pesquisa Veterinária Brasileira 30(1):21-28. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br An 18-year (1990-2007) database search in the files of the Laboratory of Veterinary Pathology (LPV) of the Universidade Federal de Santa Maria (UFSM), Rio Grande do Sul state, Brazil was carried out. In this period, 19,476 exams in domestic animals were done. Out of these exams, 6,816 (34.9%) were necropsies and 12,660 (65.1%) were performed in mailed samples from practitioners. Experimental cases were excluded from this study and corresponded to 54 necropsies and 15 histopathologic exams. After the exclusion 354 (5.1%) necropsies and 163 (1.2%) histopathologic exams were found in sheep. Out of these, 265 (74.8%) cases were conclusive in the group of necropsies and 96 (59%) were conclusive in the group of the histopathologic exams. The resulting 361 conclusive cases were grouped according to the etiology: 150 (41.6%) cases of poisoning or toxi-infections; 142 (39.3%) cases of infectious and parasitary diseases; 31 (8.6%) of metabolic and nutritional diseases; 13 (3.6%) cases of neoplasms and neoplasm-like lesions; 7 (1.9%) cases of diseases caused by physical agents; 6 (1.7%) cases of iatrogenic conditions; and 4 (1.1%) of developmental diseases. Eight cases did not fit in any of the above categories and were grouped under the denomination of other conditions. Hemonchosis and poisoning by Nierembergia veitchii were the most prevalent diseases in sheep during the 18 years of this study.

• Diseases of sheep

Abstract in Portuguese:

RESUMO.- Rissi D.R., Pierezan F., Oliveira Filho J.C., Fighera R.A., Irigoyen L.F., Kommers G.D. & Barros C.S.L. 2010. [Diseases of sheep from central Rio Grande do Sul State, Brazil: 361 cases.] Doenças de ovinos da região Central do Rio Grande do Sul: 361 casos. Pesquisa Veterinária Brasileira 30(1):21-28. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Foram pesquisados os arquivos do Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Santa Maria (UFSM) e revisados os diagnósticos de doenças de ovinos realizados entre 1990 e 2007. No período estudado foram realizados 19.476 exames de animais domésticos. Desses, 6.816 (34,9%) correspondiam a necropsias e 12.660 (65,1%) a exames histopatológicos realizados em materiais enviados por veterinários de campo. Materiais provenientes de experimentos em ovinos foram excluídos deste estudo, sendo obtidas 354 (5,1%) necropsias e 163 (1,2%) exames histopatológicos de ovinos. O diagnóstico foi conclusivo em 265 (74,8%) casos de necropsias e em 96 (59%) casos dos exames histopatológicos, somando 361 casos conclusivos. Esses casos foram divididos em grupos conforme a etiologia: 150 casos (41,6%) de intoxicações e toxiinfecções; 142 casos (39,3%) de doenças infecciosas e parasitárias; 31 casos (8,6%) de doenças metabólicas e nutricionais; 13 casos (3,6%) de neoplasmas e lesões tumoriformes; sete casos (1,9%) de distúrbios causados por agentes físicos; seis casos (1,7%) de distúrbios iatrogênicos; e quatro casos (1,1%) de distúrbios do desenvolvimento. Oito casos (2,2%) foram classificados em outros distúrbios por não se enquadrarem em nenhum dos outros grupos. Hemoncose e intoxicação por Nierembergia veitchii foram as doenças mais importantes para ovinos nesses 18 anos.

Abstract in English:

ABSTRACT.- Rissi D.R., Pierezan F., Kommers G.D. & Barros C.S.L. 2008. [Occurrence of rabies in sheep in Rio Grande do Sul, Brazil.] Ocorrência de raiva em ovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(10):495-500. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of rabies in sheep occurring in November 2003, in central Rio Grande do Sul state, Brazil, are described. A 3-month-old male, and a 2.5-month-old female sheep were affected. Clinical signs were characterized by abnormal gait, trembling, lateral recumbency, convulsion, opisthotonus, and fever. Histological findings included a non-suppurative myelomeningoencephalitis associated with intracytoplasmic eosinophilic inclusion (Negri) bodies in neurons. Lesions were predominantly observed in gray matter of the spinal cord, brainstem and cerebellum. There was non-suppurative Gasserian ganglionitis in one sheep in which this structure was examined. Immunohistochemistry using rabies virus ribonucleoprotein polyclonal antibody yelded positive result in brain tissue from both sheep. The cases herein reported occurred concomitantly to an outbreak of bat transmitted rabies in cattle in the same region and were considered, on epidemiological basis, to be transmitted by bats, as occurs in endemic bovine rabies in Rio Grande do Sul.

• Lyssavirus Rhabdoviridae rabies diseases of sheep immunohistochemistry neuropathology

Abstract in Portuguese:

ABSTRACT.- Rissi D.R., Pierezan F., Kommers G.D. & Barros C.S.L. 2008. [Occurrence of rabies in sheep in Rio Grande do Sul, Brazil.] Ocorrência de raiva em ovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(10):495-500. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of rabies in sheep occurring in November 2003, in central Rio Grande do Sul state, Brazil, are described. A 3-month-old male, and a 2.5-month-old female sheep were affected. Clinical signs were characterized by abnormal gait, trembling, lateral recumbency, convulsion, opisthotonus, and fever. Histological findings included a non-suppurative myelomeningoencephalitis associated with intracytoplasmic eosinophilic inclusion (Negri) bodies in neurons. Lesions were predominantly observed in gray matter of the spinal cord, brainstem and cerebellum. There was non-suppurative Gasserian ganglionitis in one sheep in which this structure was examined. Immunohistochemistry using rabies virus ribonucleoprotein polyclonal antibody yelded positive result in brain tissue from both sheep. The cases herein reported occurred concomitantly to an outbreak of bat transmitted rabies in cattle in the same region and were considered, on epidemiological basis, to be transmitted by bats, as occurs in endemic bovine rabies in Rio Grande do Sul.

Abstract in English:

Rozza D.B., Raymundo D.L., Corrêa A.M.R., Seitz A.L., Driemeier D. & Colodel E.M. 2006. [Spontaneous Baccharis coridifolia (Compositae) poisoning in sheep.] Intoxicação espontânea por Baccharis coridifolia (Compositae) em ovinos. Pesquisa Veterinária Brasileira 26(1):21-25. Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: moleta@terra.com.br An outbreak of Baccharis coridifolia (Compositae) poisoning in sheep is reported, which occurred in November 2004 in the county of Caxias do Sul, Rio Grande do Sul (RS), southern Brazil. From a herd of 212 sheep, coming from a Baccharis coridifolia free area, in the county of Jaguarão, RS, 35 sheep died until 5 days after the arrival in the new area where the plant was found with abundance. The clinical signs began 8 hours after introduction of the animals into the new pasture and included apathy, anorexia, abdominal retraction or mild distension, weakness of hind limbs, dry feces, sternal ou lateral decumbency, struggling movements, coma and death. Clinical evolution was from 5 to 48 hours. Other sheep that were already before on the pasture were not affected. Main necropsy findings were in the gastrointestinal tube, with wall and serosal oedema, mainly in the reticulo-ruminal fold and of the abomasum, reddening and detachment of the mucosa of forestomachs, and intense hemorrhage in the submucosa. Histopathological findings were degeneration and necrosis of the epithelium of the forestomachs with polymorphonuclear infiltration associated with bacterial colonies, congestion, hemorrhage and oedema, and lymphoid tissue necrosis.

• Poisonous plants Baccharis coridifolia Compositae plant poisoning diseases of sheep pathology.

Abstract in Portuguese:

Rozza D.B., Raymundo D.L., Corrêa A.M.R., Seitz A.L., Driemeier D. & Colodel E.M. 2006. [Spontaneous Baccharis coridifolia (Compositae) poisoning in sheep.] Intoxicação espontânea por Baccharis coridifolia (Compositae) em ovinos. Pesquisa Veterinária Brasileira 26(1):21-25. Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: moleta@terra.com.br An outbreak of Baccharis coridifolia (Compositae) poisoning in sheep is reported, which occurred in November 2004 in the county of Caxias do Sul, Rio Grande do Sul (RS), southern Brazil. From a herd of 212 sheep, coming from a Baccharis coridifolia free area, in the county of Jaguarão, RS, 35 sheep died until 5 days after the arrival in the new area where the plant was found with abundance. The clinical signs began 8 hours after introduction of the animals into the new pasture and included apathy, anorexia, abdominal retraction or mild distension, weakness of hind limbs, dry feces, sternal ou lateral decumbency, struggling movements, coma and death. Clinical evolution was from 5 to 48 hours. Other sheep that were already before on the pasture were not affected. Main necropsy findings were in the gastrointestinal tube, with wall and serosal oedema, mainly in the reticulo-ruminal fold and of the abomasum, reddening and detachment of the mucosa of forestomachs, and intense hemorrhage in the submucosa. Histopathological findings were degeneration and necrosis of the epithelium of the forestomachs with polymorphonuclear infiltration associated with bacterial colonies, congestion, hemorrhage and oedema, and lymphoid tissue necrosis.

Abstract in English:

ABSTRACT.- Ilha M.R.S., Loretti A.P., Barros S.S., Barros C.S.L. 2001. [Spontaneous poisoning in sheep by Senecio brasiliensis (Asteraceae) in southern Brazil] Intoxicação espontânea por Senecio brasiliensis (Asteraceae) em ovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 21(3):123-138. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: ilha76@mailcity.com An outbreak of spontaneous Senecio brasiliensis poisoning in grazing sheep in the county of Mata, Rio Grande do Sul, southern Brazil, is described. The disease occurred on one farm in middlejanuary 1997. Fifty-one (54.25%) out of 94 sheep were affected, and 50 animals (53.2%) died. This flock of sheep had been grazing for approximately 7 months (from June 1996 to January 1997) in paddocks heavily infested with S. brasiliensis. Clinical signs included photodermatitis, progressive emaciation, apathy, weakness, neurological signs such as drownsiness, aimless walking and unsteady gait, jaundice and hemoglobinuria. There was amelioration of the skin lesions in those sheep that developed hepatogenous photosensitization. Main necropsy findings in 9 sheep included small, firm, tan or greenish liver with few to numerous small, yellowish, well-circumscribed nodules measuring up to 3 mm in diameter and randomly scattered throughout the hepatic parenchyma. There was also marked distension of the gallbladder which contained large amounts of inspissated, dark green bile and straw-colored cavitary effusions (hydropericardium and ascitis). Five sheep developed lethal acute hemolytic crisis, secondary to massive release into the blood stream of copper accumulated in the liver (hepatogenous chronic copper poisoning). Apart from the aforementioned liver lesions, other gross findings in those animals included severe and diffuse jaundice, dark brown urine (hemoglobinuria) and swollen, friable, finely stippled or diffusely dark kidneys. The main histopathological findings included hepatomegalocytosis, biliary ductal proliferation (bile duct hyperplasia) and moderate periportal fibrosis. The portal triads were infiltrated with variable numbers of mononuclear cells. There was heavy accumulation of brownish pigment in macrophages identified as ceroid or copper with PAS and rhodanine stainings, respectively. Those ceroid and copper-laden macrophages were scattered on the remnant hepatic parenchyma or formed small aggregates in the portal triads. Main histopathological findings in the kidneys of 5 sheep, that developed fatal hepatogenous chronic copper poisoning, included tubular nephrosis, accumulation of hemoglobin and hemosiderin in epithelial tubular cells and hemoglobin casts (hemoglobinuric nephrosis). Morphological evidence of hepatic encephalopathy included spongy degeneration (status spongiosus) of the cerebral white matter. Ultrastructural changes in the tiver of affected sheep included degenerative hepatocellular changes of varying severity. There was accumulation of numerous lipid droplets in the cytoplasm of the hepatocytes and lysosomes containing substances of high electron-density that corresponded to ceroid-lipofuscin in most of the cases. In addition, there was mild swelling of the rough endoplasmic reticulum and moderate hyperplasia of the smooth endoplasmic reticulum in some areas of the cytoplasm of the hepatocytes. Proximal convoluted tubular epithelial cells showed intracellular edema anda variety of mitochondrial degenerative changes. These included disarrangement and breakup of cristae, finely granular matrix, accumulation of lipid globules and rupture of the membranes in a few cases. Many epithelial tubular cells displayed substances of high electron-densitywithin lysosomes. Chemical analysis of copper in tiver and kidney samples of affected sheep revealed high concentrations varying from 369 ppm to 1248 ppm in the tiver and ranging from 152 ppm to 687 ppm in the kidneys (dry matter). The diagnosis of Senecio brasiliensis poisoning was based on epidemiological data, clinical signs, necropsy findings, histological lesions and laboratory data.

• Senecio brasiliensis Asteraceae diseases of sheep poisonous plants copper toxicosis pathology doenças de ovinos plantas tóxicas intoxicação por cobre patologia

Abstract in Portuguese:

RESUMO.- Ilha M.R.S., Loretti A.P., Barros S.S., Barros C.S.L. 2001. [Spontaneous poisoning in sheep by Senecio brasiliensis (Asteraceae) in southern Brazil] Intoxicação espontânea por Senecio brasiliensis (Asteraceae) em ovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira21(3):123-138. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: ilha76@mailcity.com Descreve-se a ocorrência de um surto de intoxicação espontânea por Senecio brasiliensis em ovinos em um estabelecimento do município de Mata, Estado do Rio Grande do Sul, em meados de janeiro de 1997. De um total de 94 ovinos, 51 (54,25%) animais adoeceram e 50 (53,2%) morreram. Esse rebanho permaneceu durante aproximadamente 7 meses (de junho de 1996 a janeiro de 1997) em piquetes de pastagem nativa onde havia grande quantidade de S. brasiliensis. O quadro clínico manifestado pelos animais afetados consistia em fotossensibilização, emagrecimento progressivo, apatia, fraqueza, perturbações neurológicas como depressão, andar a esmo e desequilibrado, icterícia e hemoglobinúria. Houve melhora das lesões de pele naqueles ovinos que desenvolveram fotossensibilização hepatógena depois que foram retirados do sol. As principais lesões macroscópicas observadas em 9 dos 10 ovinos necropsiados incluíam fígado diminuído de tamanho, firme, difusamente marrom amarelado ou esverdeado, com quantidades variáveis de nódulos de 1-3 mm de diâmetro, bem circunscritos, salientes na cápsula, amarelados, distribuídos aleatoriamente por todo o parênquima. A vesícula biliar estava repleta e preenchida por bile verde escura e espessa. Havia também derrames cavitários (hidropericárdio e ascite). Crise hemolítica aguda fatal associada à intoxicação crônica hepatógena por cobre foi observada em cinco ovinos. Além das lesões hepáticas macroscópicas já mencionadas, foi observada icterícia generalizada da carcaça, rins tumefeitos, friáveis, difusamente escurecidos ou com fino pontilhado enegrecido; a urina era marrom escura (hemoglobinúria). As principais lesões microscópicas foram observadas no fígado e consistiam em hepatomegalocitose, proliferação de duetos biliares (hiperplasia ductal) e fibrose periportal moderada acompanhada de infiltrado inflamatório mononuclear. Macrófagos carregados de pigmento acastanhado formavam aglomerados nas tríades portais ou estavam dispersos entre os hepatócitos remanescentes. O material armazenado no citoplasma desses macrófagos correspondia a ceróide e cobre, positivo nas técnicas de PAS e rodanina, respectivamente. Nos rins de cinco animais, havia nefrose hemoglobinúrica caracterizada por degeneração e necrose do epitélio tubular, presença de hemoglobina e hemossiderina no citoplasma das células epiteliais dos túbulos contorcidos e cilindros de hemoglobina na luz tubular. Evidência morfológica de encefalopatia hepática incluía degeneração esponjosa (status spongiosus) da substância branca do encéfalo. Achados ultra-estruturais no fígado incluíam graus variáveis de degeneração hepatocelular caracterizada pelo acúmulo de numerosas gotas lipídicas no citoplasma das células hepáticas e presença de lisossomos carregados de material eletrodenso que, na maioria dos casos, correspondia à lipofuscina-ceróide. Adicionalmente, havia discreta dilatação do retículo endoplasmático rugoso e moderada hiperplasia do retículo endoplasmático liso em algumas regiões do citoplasma dos hepatócitos. No epitélio dos túbulos contorcidos proximais do rim foi observado edema intracelular e diversas alterações mitocondriais de caráter degenerativo que incluíam tumefação, desorganização e ruptura das cristas, matriz finamente granular, acúmulo de gotículas de gordura e ruptura das membranas em alguns casos. Lisossomos contendo material fortemente eletrodenso foram observados em muitas células tubulares renais. O exame laboratorial de fragmentos de fígado e rim dos ovinos afetados revelou níveis elevados de cobre que variaram respectivamente de 369 ppm a 1248 ppm e 152 ppm a 687 ppm com base na matéria seca. O diagnóstico de intoxicação por Senecio brasiliensis baseou-se em dados epidemiológicos, clínicos, de necropsia, histopatológicos e laboratoriais.

Abstract in English:

ABSTRACT.- Loretti A.P., Bezerra P.S., Ilha M.R.S., Barros S.S. & Barros C.S.L. 1999. [Experimental poisoning by the burs of Xanthium cavanillesii (Asteraceae) in sheep.] Intoxicação experimental pelos frutos de Xanthium cavanillesii (Asteraceae) em ovinos. Pesquisa Veterinária Brasileira 19(2):71-78. Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. The ground burs of Xanthium cavanillesii (Asteraceae) were force fed to 15 adult sheep in single doses or divided in two doses. Nine sheep died. Doses of 2 g/kg and above were lethal for the sheep. A single dose of 1,25 g/kg and a total of 2,5 g/kg divided in two administrations of 1,25 g/kg consecutive daily doses did not cause the toxicosis. Clinical signs were observed only in the animals that died and occurred between 5 hours and 20 hours after the beginning of the administration of the burs. The toxicosis had a peracute (90 minutes to 3 hours) to acute (9 to 13 hours) course. Clinical signs included apathy, anorexia, decreased rate and intensity of ruminai movements, generalized muscle tremors, stiff and incoordinated gait, unwillingness to move, instability, falls and recumbency. Most affected sheep presented seromucous nasal discharge with labored breathing. In terminal stages, there were trismus, drooling of saliva, convulsive seizures, nystagmus, paddling movements, periods of apnea and death. Main necropsy findings included accentuation of the lobular pattern of the liver, focal hemorrhages on thé capsular and cut surfaces, distension accompanied by edema and hemorrhages of the gall bladder wall, ascites, hydrotorax, and translucent and gelatinous perirenal edema. The contents of the cecum and proximal loop of the ascending colon were dry, impacted and covered by mucos and streaks of clotted blood; there were disseminated petechiae and suffusions. The main histopathological change consisted of marked coagulative hepatocellular necrosis, which varied from centrilobular to massive, associated with congestion and hemorrhages. In the remaining of the hepatic lobule there was either swelling or vacuolation of the hepatocytes.

• Poisonous plants hepatotoxicosis Xanthium cavanillesii Asteraceae diseases of sheep pathology Plantas tóxicas hepatotoxicose doenças de ovinos patologia.

Abstract in Portuguese:

RESUMO.- Loretti A.P., Bezerra P.S., Ilha M.R.S., Barros S.S. & Barros C.S.L. 1999. [Experimental poisoning by the burs of Xanthium cavanillesii (Asteraceae) in sheep.] Intoxicação experimental pelos frutos de Xanthium cavanillesii (Asteraceae) em ovinos. Pesquisa Veterinária Brasileira 19(2):71-78. Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. Os frutos moídos de Xanthium cavanillesii foram administrados por via oral, em doses únicas ou fracionadas, a 15 ovinos adultos. Nove ovinos morreram. Doses a partir de 2 g/kg em uma única administração foram letais para os ovinos. Doses únicas de 1,25 g/kg e doses de 2,5 g/kg subdivididas em duas administrações diárias (1,25 g/kg em dois dias consecutivos) não causaram a intoxicação. Sinais clínicos foram observados apenas nos animais que morreram. Iniciavam entre 5 horas e 20 horas após o início da administração dos frutos. A evolução do quadro clínico foi superaguda (90 minutos a 3 horas) ou aguda (9 a 13 horas). Sinais clínicos incluíam apatia, anorexia, hipomotilidade ruminai, tremores musculares generalizados, incoordenação motora, andar rígido, relutância em caminhar, instabilidade, quedas e decúbito. Muitos animais apresentavam corrimento nasal seromucoso que dificultava a respiração. Nas fases terminais havia tiques, sialorréia, convulsões, nistagmo, movimentos de pedalagem e períodos de apnéia seguidos de morte. Os principais achados de necropsia incluíam acentuação do padrão lobular do fígado acompanhada de petéquias distribuídas aleatoriamente na superfície capsular e de corte, distensão da vesícula biliar associada a edema e hemorragias na parede, ascite, hidrotórax, edema gelatinoso e translúcido da região perirrenal, conteúdo do ceco e alça proximal do cólon ascendente ressequido, compactado, recoberto por muco e estrias de sangue coagulado. Havia petéquias e sufusões disseminadas. A principal lesão microscópica consistia em acentuada necrose coagulativa hepatocelular centrolobular ou massiva acompanhada de congestão e hemorragia e vacuolização ou tumefação dos hepatócitos remanescentes.