Resultado da pesquisa (17)
Termo utilizado na pesquisa polioencefalomalacia
#11 - Experimentally amprolium-induced polioencephalomalacia in sheep, 29(9):747-752
Abstract in English:
ABSTRACT.- Sant’Ana F.J.F., Nogueira A.P.A., Souza R.I.C., Cardinal S.G., Lemos R.A.A. & Barros C.S.L. 2009. [Experimentally amprolium-induced polioencephalomalacia in sheep.] Polioencefalomalacia experimental induzida por amprólio em ovinos. Pesquisa Veterinária Brasileira 29(9):747-752. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br
In order to establish an experimental model for the study of the etiology, pathology, and pathogenesis of polioencephalomalacia in ruminants, the condition was induced in five sheep by oral administration of amprolium at daily doses of 500 and 1,000mg per kg of body weight respectively for 28-59 days and for 13-39 days. All sheep died or were euthanized in extremis after illness of 3-7 days. Clinical signs included depression, incoordination, midriasis, grinding of the teeth, blindness, and laying down with opisthotonus and paddling movements. Drooling and a sawhorse stance were observed in one sheep and myoclonus in another one. Main gross lesions were restricted to the central nervous system and included swelling of the brain with flattening of telencephalic gyri, and hemorrhages in the parietal and occipital lobes of the telencephalon, in the submeningeal areas of the spinal cord and in the mesencephalon. Histologically, there was segmental laminar neuronal necrosis (red neurons) associated with edema, swelling of endothelial cells, hemorrhages and infiltration by foamy macrophages (gitter cells). These changes were more marked in the frontal, parietal and occipital telecephalic lobes and there was sharp demarcation between the lesions and the adjacent normal neuropile. Additionally, similar, but less marked lesions were seen in the mesencephalon, thalamus and hippocampus. Considering the consistent reproducible aspects of polioencephalomalacia in sheep using amprolium, this may be an useful model for the study of the disease.
Abstract in Portuguese:
RESUMO.- Sant’Ana F.J.F., Nogueira A.P.A., Souza R.I.C., Cardinal S.G., Lemos R.A.A. & Barros C.S.L. 2009. [Experimentally amprolium-induced polioencephalomalacia in sheep.] Polioencefalomalacia experimental induzida por amprólio em ovinos. Pesquisa Veterinária Brasileira 29(9):747-752. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br
Para estabelecer um modelo experimental para o estudo da etiologia, patologia e patogênese da polioencefalomalacia em ruminantes, a condição foi induzida em cinco ovinos pela administração oral de amprólio nas doses diárias de 500 e 1.000mg/kg de peso animal, respectivamente por 28-59 dias e 13-39 dias. Todos os ovinos morreram ou foram eutanasiados in extremis após um curso clínico de 3-7 dias. Os sinais clínicos incluíam depressão, incoordenação, midríase, bruxismo, cegueira e decúbito com opistótono e movimentos de pedalagem. Salivação excessiva e posição de cavalete foi observada em um ovino e mioclonias em um outro. Os principais achados de necropsia restringiam-se ao sistema nervoso central e incluíam tumefação do encéfalo com achatamento dos giros telencefálicos e hemorragias nos lobos parietal e occipital do telencéfalo; as hemorragias ocorriam também nas áreas submeníngeas da medula espinhal e do mesencéfalo. Histologicamente, havia necrose segmentar laminar de neurônios (neurônios vermelhos) associada a edema, tumefação de células endoteliais, hemorragias e infiltração por macrófagos espumosos (células gitter). Essas alterações eram mais marcadas nos lobos frontal, parietal e occipital do telencéfalo e havia uma demarcação abrupta entre as lesões e o neurópilo normal adjacente. Adicionalmente, lesões semelhantes, mas menos acentuadas, eram observadas no mesencéfalo, tálamo e hipocampo. Levando em consideração a reproducibilidade regular dos aspectos da polioencefalomalacia em ovinos pela administração de amprólio, esse modelo pode ser útil para o estudo da doença.
#12 - Polioencefalomalacia em bovinos: epidemiologia, sinais clínicos e distribuição das lesões no encéfalo, p.487-497
Abstract in English:
ABSTRACT.- Sant’Ana F.J.F., Rissi D.R., Lucena R.B., Lemos R.A.A., Nogueira A.P.A. & Barros C.S.L. 2009. [Bovine polioencephalomalacia: epidemiology, clinical signs and distribution of lesions in the brain.] Polioencefalomalacia em bovinos: epidemiologia, sinais clínicos e distribuição das lesões no encéfalo. Pesquisa Veterinária Brasileira 29(7):487-497. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br
Thirty one cases of polioencephalomalacia (PEM) diagnosed from 1999-2008 in cattle from the Southern (13 cases) and Midwestern (18 cases) Brazil were studied. Morbidity (0.04%-6.66 %), mortality (0.04%-6.66 %), and lethality (50%-100%) rates were similar in both regions studied. There was no clear association between PEM cases and age, sex or seasonality. Cases occurred mainly in cattle raised at pasture; in the Southern the disease affected mainly young cattle (one-year old or less) while mainly older cattle (three-year-old or older) were affected in the Midwest. Clinical signs more frequently observed included blindness, incoordination, circling, opisthotonus, recumbence and peddling movements. Clinical course varied from 12 hours to 8 days (average three days and a half). In 11 cases no gross changes were observed in the brain. Main gross findings in the brain of remaining cases included congestion with swelling and flattening of gyri, softening and yellow discoloration of cerebral cortex, hemorrhagic foci in the brain stem, cerebellum and telencephalon, and cerebellar herniation. The main histopathological changes were in the cortex of occipital, parietal and frontal telencephalic lobes; however less prominent and less frequently found lesions occurred in the hippocampus, basal nuclei, thalamus, midbrain, and cerebellum. The type of microscopic cortical lesions was consistent in all cases and included segmentar laminar neuronal necrosis (red neurons), spongiosis, swollen of vascular endothelial nuclei, Alzheimer type II astrocytes and infiltration of gitter cells. In 20% of the cases there was mild lymphohistiocytic cellular infiltrate and in 13% of the cases there was mild infiltrate by neutrophils and eosinophils. Additionally, mild to moderate necro-hemorrhagic lesions were observed in 49% of the cases in the basal nuclei, in 39% of the cases in brain stem and in 26% of the cases in the thalamus. Brain lesions were consistently found in the cortical laminae of the occipital, parietal and frontal telencephalic lobes. In such locations, most frequently affected cortical layers both by neuronal necrosis and edema were external and internal granular layers. Both gyri and sulci were equally affected.
Abstract in Portuguese:
RESUMO.- Sant’Ana F.J.F., Rissi D.R., Lucena R.B., Lemos R.A.A., Nogueira A.P.A. & Barros C.S.L. 2009. [Bovine polioencephalomalacia: epidemiology, clinical signs and distribution of lesions in the brain.] Polioencefalomalacia em bovinos: epidemiologia, sinais clínicos e distribuição das lesões no encéfalo. Pesquisa Veterinária Brasileira 29(7):487-497. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br
RESUMO.- Trinta e um casos de polioencefalomalacia (PEM) diagnosticados de 1999-2008 em bovinos do Sul (13 casos) e Centro-Oeste (18 casos) brasileiros foram estudados. As taxas de morbidade (0,04%-6,66 %), mortalidade (0,04%-6,66 %) e letalidade (50%-100%) foram semelhantes em ambas as regiões estudadas. Não houve uma associação clara entre os casos de PEM e a idade, sexo dos bovinos e sazonalidade. Os casos ocorreram principalmente em bovinos criados de forma extensiva em pastagem. Na Região Sul a doença afetou principalmente bovinos jovens (um ano de idade ou menos), enquanto que principalmente bovinos mais velhos (3 anos de idade ou mais) foram afetados no Centro-Oeste. Os sinais clínicos mais frequentemente observados incluíram cegueira, incoordenação, andar em círculos, opistótono, decúbito e movimentos de pedalagem. A evolução do quadro clínico variou de 12 horas a 8 dias (media 3 dias e meio). Em 11 encéfalos não foram observadas alterações macroscópicas; as principais alterações macroscópicas nos outros casos incluíam congestão com tumefação e achatamento das circunvoluções, amolecimento e amarelamento do córtex telencefálico, focos de hemorragia no tronco encefálico, cerebelo e telencéfalo e herniação cerebelar. As principais alterações histológicas ocorreram no córtex dos lobos telencefálicos occipital, parietal e frontal; no entanto, lesões menos acentuadas e menos frequentemente observadas ocorreram no hipocampo, núcleos da base, tálamo, mesencéfalo e cerebelo. O tipo de lesão microscópica cortical era consistente em todos os casos e incluía necrose neuronal (neurônio vermelho) laminar segmentar, espongiose, tumefação do núcleo das células endoteliais, astrócitos Alzheimer tipo II e infiltração por células gitter. Em 20% dos casos havia um leve infiltrado celular linfo-histiocitário e em 13% dos casos havia leve infiltrado de neutrófilos e eosinófilos. Adicionalmente, lesões necro-hemorrágicas leves ou moderadas foram observadas em 49% dos casos nos núcleos da base, em 39% dos casos no tronco encefálico e em 26% dos casos no tálamo. Lesões telencefálicas foram consistentemente observadas nas lâminas dos córtices dos lobos occipital, parietal e frontal. Nessas regiões as camadas granular externa e interna foram as mais afetadas tanto por neurônios necróticos quanto por edema em todas as regiões avaliadas. Tanto os giros quanto os sulcos foram afetados igualmente.
#13 - Meningoencefalite e polioencefalomalacia causadas por Herpesvírus bovino-5 no Estado do Pará
Abstract in English:
Riet-Correa G., Duarte M.D., Barbosa J.D., Oliveira C.M.C., Cerqueira V.D., Brito M.F. & Riet-Correa F. 2006. [Meningoencephalitis and polioencephalomalacia caused by Bovine herpesvirus-5 in the state of Pará, northern Brazil.] Meningoencefalite e polioencefalomalacia causadas por Herpesvírus bovino-5 no Estado do Pará. Pesquisa Veterinária Brasileira 26(1):44-46. Central de Diagnóstico Veterinário, Universidade Federal do Pará, Maximino Porpino 1000, Castanhal, PA 68740-080, Brazil. E-mail: griet@ufpa.br
Four outbreaks of meningoencephalitis in 1 to 2 years old cattle caused by Bovine herpesvirus-5 are reported in four municipalities in the state of Pará, northern Brazil. In three outbreaks only one animal was affected, in another 3 cattle were affected. Main clinical signs were incoordination, dullness, blindness, recumbence, and opisthotonus. Death occurred after a clinical manifestation period of 3-4 days. Softening and yellowish areas were observed grossly in the cerebral cortex. The histology revealed poliencephalomalacia in the cerebral cortex, thalamus and basal nuclei, and non suppurative encephalitis and meningitis, and eosinophilic intranuclear inclusion bodies in astrocytes. The diagnosis was based on the typical microscopic lesions.
Abstract in Portuguese:
Riet-Correa G., Duarte M.D., Barbosa J.D., Oliveira C.M.C., Cerqueira V.D., Brito M.F. & Riet-Correa F. 2006. [Meningoencephalitis and polioencephalomalacia caused by Bovine herpesvirus-5 in the state of Pará, northern Brazil.] Meningoencefalite e polioencefalomalacia causadas por Herpesvírus bovino-5 no Estado do Pará. Pesquisa Veterinária Brasileira 26(1):44-46. Central de Diagnóstico Veterinário, Universidade Federal do Pará, Maximino Porpino 1000, Castanhal, PA 68740-080, Brazil. E-mail: griet@ufpa.br
Four outbreaks of meningoencephalitis in 1 to 2 years old cattle caused by Bovine herpesvirus-5 are reported in four municipalities in the state of Pará, northern Brazil. In three outbreaks only one animal was affected, in another 3 cattle were affected. Main clinical signs were incoordination, dullness, blindness, recumbence, and opisthotonus. Death occurred after a clinical manifestation period of 3-4 days. Softening and yellowish areas were observed grossly in the cerebral cortex. The histology revealed poliencephalomalacia in the cerebral cortex, thalamus and basal nuclei, and non suppurative encephalitis and meningitis, and eosinophilic intranuclear inclusion bodies in astrocytes. The diagnosis was based on the typical microscopic lesions.
#14 - Polioencefalomalacia em caprinos e ovinos na região semi-árida do Nordeste do Brasil, p.9-14
Abstract in English:
Lima E.F., Riet-Correa F., Tabosa I.M., Dantas A.F.M., Medeiros J.M. & Sucupira Júnior G. 2005. [Polioencephalomalacia in goats and sheep in the semiarid region of northeastern Brazil.] Polioencefalomalacia em caprinos e ovinos na região semi-árida do Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(1):9-14. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: riet@cstr.ufcg.edu.br
Seven outbreaks of polioencephalomalacia in goats and 3 in sheep are reported from the semiarid region of northeastern Brazil. Animals of different ages were affected in various seasons of the year. In 5 outbreaks the animals were supplemented with concentrate ration and in 5 others they were only grazing on pastures. In one outbreak sheep were supplemented with an energy-protein-mineral mixture containing 1.3% of sulfur flower. Clinical signs were characterized by blindness, depression, head pressing, circling, grinding of the teeth, incoordination, spastic paralysis, ataxia, depression of the palpebral and pupillary reflexes, lateral strabismus, nystagmus, and dilated pupils. Nine affected animals were treated with thiamine and dexamethasone; 7 of them recovered but 2 died. The diagnosis of the disease was based on the recovered animals after treatment and/or on the histologic lesions. The clinical course varied from 2 to 15 days. On three animals post-mortem examination was made. One had herniation of the cerebellum through the Foramen magnum and softening of the cerebral cortex. The cut surface of the cerebral cortex showed cavitation and yellowish discoloration. Another animal had only cerebellar herniation. In a third animal no gross lesions were observed. Histological changes in the 3 animals were laminar necrosis of the cerebral cortex, and in 2 malacia of the thalamus and the rostral colliculi was also observed. In 9 outbreaks the cause of the disease was not determined, but one was probably due to sulfur toxicosis caused by the high sulfur content of the energy-protein-mineral mixture containing 1.3% of sulfur flower (96% sulfur) and 30% chicken litter (0.39% sulfur).
Abstract in Portuguese:
Lima E.F., Riet-Correa F., Tabosa I.M., Dantas A.F.M., Medeiros J.M. & Sucupira Júnior G. 2005. [Polioencephalomalacia in goats and sheep in the semiarid region of northeastern Brazil.] Polioencefalomalacia em caprinos e ovinos na região semi-árida do Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(1):9-14. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: riet@cstr.ufcg.edu.br
Seven outbreaks of polioencephalomalacia in goats and 3 in sheep are reported from the semiarid region of northeastern Brazil. Animals of different ages were affected in various seasons of the year. In 5 outbreaks the animals were supplemented with concentrate ration and in 5 others they were only grazing on pastures. In one outbreak sheep were supplemented with an energy-protein-mineral mixture containing 1.3% of sulfur flower. Clinical signs were characterized by blindness, depression, head pressing, circling, grinding of the teeth, incoordination, spastic paralysis, ataxia, depression of the palpebral and pupillary reflexes, lateral strabismus, nystagmus, and dilated pupils. Nine affected animals were treated with thiamine and dexamethasone; 7 of them recovered but 2 died. The diagnosis of the disease was based on the recovered animals after treatment and/or on the histologic lesions. The clinical course varied from 2 to 15 days. On three animals post-mortem examination was made. One had herniation of the cerebellum through the Foramen magnum and softening of the cerebral cortex. The cut surface of the cerebral cortex showed cavitation and yellowish discoloration. Another animal had only cerebellar herniation. In a third animal no gross lesions were observed. Histological changes in the 3 animals were laminar necrosis of the cerebral cortex, and in 2 malacia of the thalamus and the rostral colliculi was also observed. In 9 outbreaks the cause of the disease was not determined, but one was probably due to sulfur toxicosis caused by the high sulfur content of the energy-protein-mineral mixture containing 1.3% of sulfur flower (96% sulfur) and 30% chicken litter (0.39% sulfur).
#15 - Polioencephalomalacia in cattle in the states of Mato Grosso do Sul and São Paulo, 20(3):119-125
Abstract in English:
ABSTRACT.- Nakano L., Lemos R.A.A. & Riet-Correa F. 2000. [Polioencephalomalacia in cattle in the states of Mato Grosso do Sul and São Paulo.] Polioencefalomalacia em bovinos nos estados de Mato Grosso do Sul e São Paulo. Pesquisa Veterinária Brasileira 20(3):119-125. Depto Patologia, Fac. Veterinária, Universidade Federal de Pelotas, 96010-900 Pelotas, RS, Brazil.
Thirty outbreaks of polioencephalomalacia (PEM) were diagnosed from August 1993 to October 1997. Twenty nine occurred in the state of Mato Grosso do Sul and one in São Paulo. The disease affected cattle from 4 months to 7 years of age. Morbidity rates ranged from 0.02% to 14.28% and case fatalities from 42.5 % to 100%. The disease was not seasonal. All outbreaks occurred in cattle grazing Brachiaria spp, except one affecting feedlot cattle. Only neurologic signs were observed, and the course of the disease varied from 12 hours to 4 days in untreated cattle. Most animals treated with thiamine anel dexamethazone recovered. Moderate cerebral edema was observed at necropsy. Cell changes were characterized by laminar necrosis and gitter cells. In two cases moderate cortical anel submeningeal hemorrhages were observed. Nine cases had perivascular anel submeningeal infiltrations by eosinophils. Sodium ion concentration of the cerebrospinal fluid was elevated in one case. The cause of PEM in the region was not determined, but the results suggest that in some cases sodium chloride intoxication/water deprivation could play a role in the etiology of the disease. PEM represents 4.78% of cattle disease diagnosed at the Pathology Laboratory of the Federal University of Mato Grosso do Sul.
Abstract in Portuguese:
RESUMO.- Nakano L., Lemos R.A.A. & Riet-Correa F. 2000. [Polioencephalomalacia in cattle in the states of Mato Grosso do Sul and São Paulo.] Polioencefalomalacia em bovinos nos estados de Mato Grosso do Sul e São Paulo. Pesquisa Veterinária Brasileira 20(3):119-125. Depto Patologia, Fac. Veterinária, Universidade Federal de Pelotas, 96010-900 Pelotas, RS, Brazil.
Trinta focos de polioencefalomalacia (PEM) foram diagnosticados no período de agosto de 1993 a outubro de 1997. Vinte e nove focos ocorreram no estado de Mato Grosso do Sul (MS) e um no estado de São Paulo (SP). Foram afetados bovinos de 4 a 84 meses de idade. A morbidade dos rebanhos afetados variou ele 0,02% a 14,28% e a letalidade de 42,5% a 100%. A doença não apresentou uma sazonalidade e ocorreu em vários municípios do MS. Em todos os focos estudados os animais afetados eram criados em regimes de criação extensiva, com exceção de um foco. Os sinais clínicos observados foram exclusivamente nervosos e a evolução dos casos variou de 12 horas a 4 dias. A maioria dos animais tratados com tiamina e dexametasona recuperou-se. Histologicamente, as lesões consistiam de necrose laminar do córtex cerebral. Adicionalmente em 2 casos observaram-se hemorragias submeningeanas e corticais, e em 9 casos presença ele infiltrado de eosinófilos. A dosagem de sódio no líquor apresentou-se elevada em um caso. A etiologia da PEM não está esclarecida, porém em alguns casos a intoxicação por cloreto de sódio/privação de água pode estar envolvida na etiologia da enfermidade. A PEM representa 4,78% dos casos ele enfermidades de bovinos diagnosticadas no Laboratório de Anatomia Patológica da UFMS. Com bases nos resultados, verifica-se a importância da enfermidade no diagnóstico diferencial de outras doenças com quadro clínico neurológico no MS, principalmente a raiva, a meningoencefalite por herpesvírus bovino tipo 5 (HVB-5) e o botulismo.
#16 - Meningoencephalitis in cattle caused by bovine herpesvirus-5 in Mato Grosso do Sul and São Paulo, 18(2):76-83
Abstract in English:
ABSTRACT.- Salvador S.C., Lemos R.A.A., Riet-Correa F., Roehe P.M. & Osório A.L.A.R. 1998. [Meningoencephalitis in cattle caused by bovine herpesvirus-5 in Mato Grosso do Sul and São Paulo.] Meningoencefalite em bovinos causada por herpesvírus bovino-5 no Mato Grosso do Sul e São Paulo. Pesquisa Veterinária Brasileira 18(2):76-83. Depto Medicina Veterinária, Universidade Federal do Mato Grosso do Sul, Cx. Postal 649, Campo Grande, MS 79070-900, Brazil.
Fifteen outbreaks of bovine herpesvirus-type 5 (BHV-5) infection were diagnosed from August 1993 to December 1996. Fourteen outbreaks occurred in the State of Mato Grosso do Sul and one in the State of São Paulo. Cattle 6 to 60 months old were affected. Morbidity reached 0.05% to 5% and case fatality rate was nearly 100%. The disease occurred in diferente municipalities and at different times of the yea1: Clinical signs were exclusively nervous, and the clinical course varied from 1 to 15 days. The main histologic lesions were meningitis, diffuse encephalitis and necrosis of the cerebral cortex with intranuclear inclusion bodies in astrocytes and neurons. BHV-5 was isolated from 11 out of 12 brains of infected animals inoculated in calf testis cells and MDBK cells. The vírus was identified by immunoperoxidase stainingwith use of monoclonal specific antibodies. Outbreaks of infection by BHV-5 represent 5% of the total number of bovine cases submitted for diagnosis to the Clinical Hospital of the University of Mato Grosso do Sul. These results indicate the importance of the disease in Mato Grosso do Sul and the need for its differentiation from other diseases which affect the nervous system.
Abstract in Portuguese:
RESUMO.- Salvador S.C., Lemos R.A.A., Riet-Correa F., Roehe P.M. & Osório A.L.A.R. 1998. [Meningoencephalitis in cattle caused by bovine herpesvirus-5 in Mato Grosso do Sul and São Paulo.] Meningoencefalite em bovinos causada por herpesvírus bovino-5 no Mato Grosso do Sul e São Paulo. Pesquisa Veterinária Brasileira 18(2):76-83. Depto Medicina Veterinária, Universidade Federal do Mato Grosso do Sul, Cx. Postal 649, Campo Grande, MS 79070-900, Brazil.
Quinze focos de meningoencefalite por herpesvírus bovino-5 (BHV-5) foram diagnosticados entre agosto de 1993 e dezembro de 1996, sendo 14 provenientes do estado do Mato Grosso do Sul e um do estado de São Paulo. A doença ocorreu em diversos municípios e em diferentes épocas do ano. Foram afetados bovinos de 6 a 60 meses de idade, com uma morbidade de 0,05% a 5% e letalidade próxima a 100%. Os sinais clínicos foram exclusivamente nervosos e o curso da enfermidade variou de 1 a 15 dias. As principais lesões histológicas detectadas foram meningite e encefalite difusa com malacia do córtex cerebral e presença de corpúsculos de inclusão intranucleares em astrócitos e neurônios. O vírus foi isolado do cérebro de 11 de um total de 12 animais, e sua identidade confirmada por imunoperoxidase, utilizando-se anticorpos monoclonais específicos. Os surtos de encefalite por BHV-5 representam 5% dos diagnósticos realizados em bovinos pelo Hospital Veterinário da Universidade Federal do Mato Grosso do Sul. Os resultados deste trabalho evidenciam a importância da doença no Mato Grosso do Sul e indicam a necessidade de incluir a encefalite por BHV-5 no diagnóstico diferencial de outras doenças do sistema nervoso de bovinos frequentes no Estado.
#17 - Polioencephalomalacia in cattle in Rio Grande do Sul, Brazil
Abstract in English:
Three cases of spontaneously occurring polioencephalomalacia (cerebrocortical necrosis) of cattle in Rio Grande do Sul, Brazil, are described. The affected animals ranged in. age from 8 to 12 months and were from different areas of the State. Clinical findings included anorexia, salivation, incoordination (ataxia), circling, blindness and opisthotonus. Two of the animals died 4 days after the appearance of clinical signs. Lesions in the central nervous system consisted of depressed, asymetrical, yellow or reddish areas in the cortex of both cerebral hemispheres. Histopathological examination of those areas revealed liquefaction of the gray inatter associated with perivascular infiltration of mononuclear cells. Hemmorrhagic lesions were observed in one case. One of the affected animals recovered after being treated with thiamine.
Abstract in Portuguese:
É descrita a ocorrência da polioencefalomalácia (necrose córtico-cerebral) em três bovinos do Rio Grande do Sul, Brasil. Os animais, com idades de 8 e 12 meses, procedentes de diferentes regiões do Estado, mostravam inapetência, salivação, incoordenação de movimentos, andar em círculo, cegueira e·opistótono. A morte de dois animais ocorreu 4 dias apôs o início dos sintomas. As lesões do sistema nervoso central consistiam em áreas deprimidas e assimétricas, de cor amarelada ou avermelhada, atingindo o córtex de ambos os hemisférios cerebrais. Estas lesões correspondiam, microscopicamente, a áreas de necrose de liquefação da substância cinzenta do córtex, associadas a infiltrado inflamatório linfocitário e, em um caso, a hemorragia. Um dos animais doentes recuperou-se apôs o tratamento com tiamina o que encorajou os autores a acreditarem que também na etiologia desses casos, a deficiência desta vitamina esteja envolvida.
