PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

• Status spongiosus astrocytic edema congenital diseases cattle

Abstract in Portuguese:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

Abstract in English:

ABSTRACT.- Seixas J.N., Peixoto P.V., Armién A.G., Jabour F.F. & Brito M.F. 2006. [Clinical and pathogenetic aspects of abamectin poisoning in calves.] Aspectos clínicos e patogenéticos da intoxicação por abamectina em bezerros. Pesquisa Veterinária Brasileira 26(3):161-166. Pro-jeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: josiseixas@ufrrj.br Clinic-pathological aspects and the pathogenesis of experimental abamectin poisoning were studied, after subcutaneous administration of different abamectin doses in 9 calves, as well as the clini-cal and pathological aspects of 74 cases of the iatrogenic poisoning with this drug in cattle, which occurred in the states of Rio Grande do Sul, Pará, Maranhão, Paraíba and Mato Grosso do Sul. From the 9 calves submitted to experimental administration of single doses, 5 calves died (4 calves received doses 6-10 times higher than recommended, and one received the therapeutic daily dose during 11 days). Abamectin poisoning induces neurological dysfunctions, characterized by an initial phase of hyperexcitability, followed by widespread muscular hypotony and progressive depression. No macroscopic or microscopic alterations were observed in the central nervous system or in any other organ. It is concluded that abamectin is an antihelmintic which should be used with restriction, because of the risks leading to death when used in young calves, even in therapeutic doses.

• Abamectin poisoning neurological alterations calves

Abstract in Portuguese:

ABSTRACT.- Seixas J.N., Peixoto P.V., Armién A.G., Jabour F.F. & Brito M.F. 2006. [Clinical and pathogenetic aspects of abamectin poisoning in calves.] Aspectos clínicos e patogenéticos da intoxicação por abamectina em bezerros. Pesquisa Veterinária Brasileira 26(3):161-166. Pro-jeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: josiseixas@ufrrj.br Clinic-pathological aspects and the pathogenesis of experimental abamectin poisoning were studied, after subcutaneous administration of different abamectin doses in 9 calves, as well as the clini-cal and pathological aspects of 74 cases of the iatrogenic poisoning with this drug in cattle, which occurred in the states of Rio Grande do Sul, Pará, Maranhão, Paraíba and Mato Grosso do Sul. From the 9 calves submitted to experimental administration of single doses, 5 calves died (4 calves received doses 6-10 times higher than recommended, and one received the therapeutic daily dose during 11 days). Abamectin poisoning induces neurological dysfunctions, characterized by an initial phase of hyperexcitability, followed by widespread muscular hypotony and progressive depression. No macroscopic or microscopic alterations were observed in the central nervous system or in any other organ. It is concluded that abamectin is an antihelmintic which should be used with restriction, because of the risks leading to death when used in young calves, even in therapeutic doses.

Abstract in English:

ABSTRACT.- Jabour F.F., Seixas J.N., Tokarnia C.H. & Brito M.F. 2006. [Variation of the toxicity of Arrabidaea bilabiata (Bignoniaceae) in rabbits.] Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos. Pesquisa Veterinária Brasileira 26(3):171-176. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23.890-000, Brazil. E-mail: flaviajabour@bol.com.br The dried and powdered mature leaves and sprouts of Arrabidaea bilabiata (fam. Bignoniaceae), a liana or scandent shrub, were administered by stomach tube to 15 rabbits at doses of 0.25-6.0g/kg. The lowest dose of the sprouts collected in October (End of the dry season) causing death was 0.5g/kg, whilst the lowest lethal dose of sprouts collected in May (End of the rainy season) was 1.0g/kg. With the mature leaves collected in October the lowest lethal dose was of 4.0g/kg, and the lowest lethal dose of the mature leaves collected in May was 6.0g/kg. The clinical course of the poisoning was peracute. The rabbits all of a sudden fell down with struggling movements, difficult and spaced breathing, and died. At necropsy, significant alterations were not observed and histopatological examination showed, as the more important changes, vacuolar hydropic degeneration of epithelial cells of the distal convoluted renal tubules, diffuse vacuolation of the cytoplasm and necrosis of hepatocytes, presence of eosinophilic sphaerules in the sinusoids, groups of heart muscle fibers with increased eosinophilia, besides congestion in the kidneys, liver, heart and lungs. It was concluded that the toxicity of A. bilabiata varies according to the season of the year and the growth stage of the plant. The plant was most toxic in October and the sprouts were more toxic than the mature leaves, confirming the data previously obtained in experiments with cattle and buffalos.

• Poisonous plants Arrabidaea bilabiata Bignoniaceae plant poisoning rabbit pathology

Abstract in Portuguese:

ABSTRACT.- Jabour F.F., Seixas J.N., Tokarnia C.H. & Brito M.F. 2006. [Variation of the toxicity of Arrabidaea bilabiata (Bignoniaceae) in rabbits.] Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos. Pesquisa Veterinária Brasileira 26(3):171-176. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23.890-000, Brazil. E-mail: flaviajabour@bol.com.br The dried and powdered mature leaves and sprouts of Arrabidaea bilabiata (fam. Bignoniaceae), a liana or scandent shrub, were administered by stomach tube to 15 rabbits at doses of 0.25-6.0g/kg. The lowest dose of the sprouts collected in October (End of the dry season) causing death was 0.5g/kg, whilst the lowest lethal dose of sprouts collected in May (End of the rainy season) was 1.0g/kg. With the mature leaves collected in October the lowest lethal dose was of 4.0g/kg, and the lowest lethal dose of the mature leaves collected in May was 6.0g/kg. The clinical course of the poisoning was peracute. The rabbits all of a sudden fell down with struggling movements, difficult and spaced breathing, and died. At necropsy, significant alterations were not observed and histopatological examination showed, as the more important changes, vacuolar hydropic degeneration of epithelial cells of the distal convoluted renal tubules, diffuse vacuolation of the cytoplasm and necrosis of hepatocytes, presence of eosinophilic sphaerules in the sinusoids, groups of heart muscle fibers with increased eosinophilia, besides congestion in the kidneys, liver, heart and lungs. It was concluded that the toxicity of A. bilabiata varies according to the season of the year and the growth stage of the plant. The plant was most toxic in October and the sprouts were more toxic than the mature leaves, confirming the data previously obtained in experiments with cattle and buffalos.

Abstract in English:

ABSTRACT.- Rech R.R., Rissi D.R., Rodrigues A., Pierezan F., Piazer J.V.M., Kommers G.D. & Barros C.S.L. 2006. [Poisoning by Solanum fastigiatum (Solanaceae) in cattle: epidemiology, clinical signs and morphometry of cerebellar lesions.] Intoxicação por Solanum fastigiatum (Solanaceae) em bovinos: epidemiologia, sinais clínicos e morfometria das lesões cerebelares. Pesquisa Veterinária Brasileira 26(3):183-189. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Nineteen cases of Solanum fastigiatum (Solanaceae) poisoning in cattle from three municipalites in the State of Rio Grande do Sul, Brazil, occurring from 2003 to 2005, are described. Morbidity and mortality rates were respectively 6.7% and 3.4%. Average age of affected cattle was five-year-old (2 to 8-year-old) and duration of clinical courses was 3-18 months. Clinical signs observed in all affected cattle were cerebellar deficits characterized by hypermetry, incoordination, falls, muscle tremors, transitory seizures and wide base stance. One affected bovine had encephalic traumatic subdural hemorrhage and another had gross atrophy of the cerebellum. Histologically, lesions were restricted to the cerebellum and consisted of partial or complete vacuolation of the perikaria of Purkinje neurons with occasional axonal spheroids in the granular cell layer and in the white matter of the cerebellum. In advanced cases there were extensive loss of cerebellar Purkinje neurons and proliferation of the Bergmann’s glia. The morphometric evaluation of the numbers of Purkinje neurons and of the thickness of the cerebellar molecular layer indicated decreased numbers of Purkinje neurons with consequent decrease in the molecular layer thickness.

• Poisonous plants Solanum fastigiatum Solanaceae lysosomal storage diseases central nervous system diseases of cattle neuropathology

Abstract in Portuguese:

ABSTRACT.- Rech R.R., Rissi D.R., Rodrigues A., Pierezan F., Piazer J.V.M., Kommers G.D. & Barros C.S.L. 2006. [Poisoning by Solanum fastigiatum (Solanaceae) in cattle: epidemiology, clinical signs and morphometry of cerebellar lesions.] Intoxicação por Solanum fastigiatum (Solanaceae) em bovinos: epidemiologia, sinais clínicos e morfometria das lesões cerebelares. Pesquisa Veterinária Brasileira 26(3):183-189. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Nineteen cases of Solanum fastigiatum (Solanaceae) poisoning in cattle from three municipalites in the State of Rio Grande do Sul, Brazil, occurring from 2003 to 2005, are described. Morbidity and mortality rates were respectively 6.7% and 3.4%. Average age of affected cattle was five-year-old (2 to 8-year-old) and duration of clinical courses was 3-18 months. Clinical signs observed in all affected cattle were cerebellar deficits characterized by hypermetry, incoordination, falls, muscle tremors, transitory seizures and wide base stance. One affected bovine had encephalic traumatic subdural hemorrhage and another had gross atrophy of the cerebellum. Histologically, lesions were restricted to the cerebellum and consisted of partial or complete vacuolation of the perikaria of Purkinje neurons with occasional axonal spheroids in the granular cell layer and in the white matter of the cerebellum. In advanced cases there were extensive loss of cerebellar Purkinje neurons and proliferation of the Bergmann’s glia. The morphometric evaluation of the numbers of Purkinje neurons and of the thickness of the cerebellar molecular layer indicated decreased numbers of Purkinje neurons with consequent decrease in the molecular layer thickness.

Abstract in English:

ABSTRACT.- Almeida A.P.M.G., Kommers G.D., Nogueira A.P.A., Júnior L.G.B., Marques B.M.F.P. & Lemos R.A.A. 2006. [Evaluation of the toxicity of Leucaena leucocephala (Leg. Mimosoi-deae) in sheep.] Avaliação do efeito tóxico de Leucaena leucocephala (Leg.Mimosoideae) em ovinos. Pesquisa Veterinária Brasileira 26(3):190-194. Departamento de Medicina Veterinária, Faculdade de Medicina Vetetinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Av. Senador Filinto Müller 2443, Cx.Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br An experiment was performed to evaluate the toxicity of Leucaena leucocephala for sheep. Two ewes and six lambs were divided into seven treatments and fed the plant. The adult ewes did not show clinical signs of poisoning. The 4 to 5-month-old lambs presented partial wool loss 6 days after beginning of the administration of the plant and total wool loss after 12 or 20 days. The age of the sheep in this experiment suggests resistance of adult ewes and susceptibility of young lambs to L. leucocaephala poisoning.

• Poisonous plants Leucaena leucocephala Leguminosae Mimosoideae plant poisoning sheep diseases pathology

Abstract in Portuguese:

ABSTRACT.- Almeida A.P.M.G., Kommers G.D., Nogueira A.P.A., Júnior L.G.B., Marques B.M.F.P. & Lemos R.A.A. 2006. [Evaluation of the toxicity of Leucaena leucocephala (Leg. Mimosoi-deae) in sheep.] Avaliação do efeito tóxico de Leucaena leucocephala (Leg.Mimosoideae) em ovinos. Pesquisa Veterinária Brasileira 26(3):190-194. Departamento de Medicina Veterinária, Faculdade de Medicina Vetetinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Av. Senador Filinto Müller 2443, Cx.Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br An experiment was performed to evaluate the toxicity of Leucaena leucocephala for sheep. Two ewes and six lambs were divided into seven treatments and fed the plant. The adult ewes did not show clinical signs of poisoning. The 4 to 5-month-old lambs presented partial wool loss 6 days after beginning of the administration of the plant and total wool loss after 12 or 20 days. The age of the sheep in this experiment suggests resistance of adult ewes and susceptibility of young lambs to L. leucocaephala poisoning.

Abstract in English:

ABSTRACT.- D’Andrea L.A.Z., Sartor I.F., Madruga C.R., Freitas S.B.Z., Kroll L.B. & Kronka S.N. 2005. [Immunological condition of cattle in Holstein and Nelore breed in regard to Babesia bovis and B. bigemina in two regions of the State of São Paulo.] Condição imunológica de bovinos das raças Holandesa e Nelore frente a Babesia bovis e B. bigemina em duas regiões do Estado de São Paulo. Pesquisa Veterinária Brasileira 26(2):74-78.. Seção de Biologia Médica do Instituto Adolfo Lutz, Laboratório Regional de Presidente Prudente, Av. Cel José Soares Marcondes 2357, Presidente Prudente, SP 19013-050, Brazil. E-mail: zampieri@ial.sp.gov.br The immunological reply of a population to an infectious agent can vary between races and handling of this population. Regional research becomes important, in order to know the interrelation between the agent and its host. In this way, the occurrence of immunoglobulins of class G, anti-Babesia bovis and anti-Babesia bigemina in the Nelore (Bos indicus) and Hostein breed (Bos taurus), was investigated in two regions of the State of São Paulo, 300 km distant from each other. For the indirect method of ELISA, 1,161 bovine serum samples were tested. The medium frequencies of antibodies showed that in the two regions exists an enzootic stability for B. bovis in both breeds studied; even so there was a tendency of marginal area for the Nelore breed in one of the regions. Regarding B. bigemina, in both regions exists enzootic stability for the Hostein and enzootic instability for the Nelore breed. Therefore, acute cases of the disease or specific outbreaks by B. bigemina infection in the Nelore breed may occur in these regions.

• Babesia bovis Babesia bigemina ELISA cattle immunological condition.

Abstract in Portuguese:

ABSTRACT.- D’Andrea L.A.Z., Sartor I.F., Madruga C.R., Freitas S.B.Z., Kroll L.B. & Kronka S.N. 2005. [Immunological condition of cattle in Holstein and Nelore breed in regard to Babesia bovis and B. bigemina in two regions of the State of São Paulo.] Condição imunológica de bovinos das raças Holandesa e Nelore frente a Babesia bovis e B. bigemina em duas regiões do Estado de São Paulo. Pesquisa Veterinária Brasileira 26(2):74-78.. Seção de Biologia Médica do Instituto Adolfo Lutz, Laboratório Regional de Presidente Prudente, Av. Cel José Soares Marcondes 2357, Presidente Prudente, SP 19013-050, Brazil. E-mail: zampieri@ial.sp.gov.br The immunological reply of a population to an infectious agent can vary between races and handling of this population. Regional research becomes important, in order to know the interrelation between the agent and its host. In this way, the occurrence of immunoglobulins of class G, anti-Babesia bovis and anti-Babesia bigemina in the Nelore (Bos indicus) and Hostein breed (Bos taurus), was investigated in two regions of the State of São Paulo, 300 km distant from each other. For the indirect method of ELISA, 1,161 bovine serum samples were tested. The medium frequencies of antibodies showed that in the two regions exists an enzootic stability for B. bovis in both breeds studied; even so there was a tendency of marginal area for the Nelore breed in one of the regions. Regarding B. bigemina, in both regions exists enzootic stability for the Hostein and enzootic instability for the Nelore breed. Therefore, acute cases of the disease or specific outbreaks by B. bigemina infection in the Nelore breed may occur in these regions.

Abstract in English:

ABSTRACT.- Barros R.R., Irigoyen L.F., Kommers G.D., Rech R.R., Fighera R.A. & Barros C.S.L. 2006. [Poisoning by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 26(2):87-96. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of poisoning by the mushroom Ramaria flavo-brunnescens are reported in cattle from two farms located in the municipalities of Santa Maria and São Gabriel, state of Rio Grande do Sul, during April-May 2005. Out of a total of 180 yearling calves that had access to a pasture with eucalyptus woods, 19 were affected and 10 died. The clinical courses were 8-15 days and clinical signs included depression, weight loss, dehydration, drooling, loosening and loss of the long hairs of the tip of the tail, smoothening of the dorsal surface of the tongue with occasional ulceration, loosening of the corneal encasement of horns, hard and ball-shaped feces covered with a film of mucous, hypopion, hyphema and corneal opacity. Two calves had leucocytosis due to mild regenerative left shift. Nine calves were necropsied. Necropsy findings confirmed the clinical observation and additionaly included fibrinonecrotic esophagitis, mainly in the distal third of the esophageal mucosa. Histopathological changes in the skin of the tail included orthokeratotic hyperkeratosis; hair folicles with irregular contours, thickening of the tricolemmal keratin layer with occasional formation of keratin plugs, and degeneration and necrosis of the outer root sheath. At the laminar region of the hooves, there was hyperplasia of the top of epidermal laminae with irregular keratinization and retention of nuclei; several epidermal laminae were shortened and fused. There was hemorrhage, fibrin and neutrophilic infiltrate in the dermal laminae. In the mucosa of the tongue there was thinning of the covering epithelium, atrophy and loss of filiform papillae, multifocal areas of dyskeratosis, and spongiosis of the basal cell layer. In some parts the epithelium was lost and the surface consisted of granulation tissue and mixed inflammatory cell infiltrate. The esophageal mucosae of six calves had varying degree of epithelial necrosis and inflammation. The loss of the covering epithelium revealed an underneath area of granulation tissue with heavy inflammatory infiltrate composed predominantly of neutrophils and macrophages. In six calves there were focal symmetric bilateral areas of malacia observed at the level of obex in the medulla oblongata and affecting the white matter and parts of the dorsal nucleus of the vagus and of the hypoglossal nucleus. The epidemiology, clinical signs, pathology, and pathogenesis of poisoning by R. flavo-brunnescens in cattle are discussed.

• Poisonous plants Ramaria flavo-brunnescens Clavariaceae plant poisoning mushroom poisoning keratinization defect focal symmetric encephalomalacia diseases of cattle pathology.

Abstract in Portuguese:

ABSTRACT.- Barros R.R., Irigoyen L.F., Kommers G.D., Rech R.R., Fighera R.A. & Barros C.S.L. 2006. [Poisoning by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 26(2):87-96. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of poisoning by the mushroom Ramaria flavo-brunnescens are reported in cattle from two farms located in the municipalities of Santa Maria and São Gabriel, state of Rio Grande do Sul, during April-May 2005. Out of a total of 180 yearling calves that had access to a pasture with eucalyptus woods, 19 were affected and 10 died. The clinical courses were 8-15 days and clinical signs included depression, weight loss, dehydration, drooling, loosening and loss of the long hairs of the tip of the tail, smoothening of the dorsal surface of the tongue with occasional ulceration, loosening of the corneal encasement of horns, hard and ball-shaped feces covered with a film of mucous, hypopion, hyphema and corneal opacity. Two calves had leucocytosis due to mild regenerative left shift. Nine calves were necropsied. Necropsy findings confirmed the clinical observation and additionaly included fibrinonecrotic esophagitis, mainly in the distal third of the esophageal mucosa. Histopathological changes in the skin of the tail included orthokeratotic hyperkeratosis; hair folicles with irregular contours, thickening of the tricolemmal keratin layer with occasional formation of keratin plugs, and degeneration and necrosis of the outer root sheath. At the laminar region of the hooves, there was hyperplasia of the top of epidermal laminae with irregular keratinization and retention of nuclei; several epidermal laminae were shortened and fused. There was hemorrhage, fibrin and neutrophilic infiltrate in the dermal laminae. In the mucosa of the tongue there was thinning of the covering epithelium, atrophy and loss of filiform papillae, multifocal areas of dyskeratosis, and spongiosis of the basal cell layer. In some parts the epithelium was lost and the surface consisted of granulation tissue and mixed inflammatory cell infiltrate. The esophageal mucosae of six calves had varying degree of epithelial necrosis and inflammation. The loss of the covering epithelium revealed an underneath area of granulation tissue with heavy inflammatory infiltrate composed predominantly of neutrophils and macrophages. In six calves there were focal symmetric bilateral areas of malacia observed at the level of obex in the medulla oblongata and affecting the white matter and parts of the dorsal nucleus of the vagus and of the hypoglossal nucleus. The epidemiology, clinical signs, pathology, and pathogenesis of poisoning by R. flavo-brunnescens in cattle are discussed.

Abstract in English:

ABSTRACT.- Rissi D.R., Oliveira F.N., Rech R.R., Pierezan F., Lemos R.A.A. & Barros C.S.L. 2006. [Epidemiology, clinical signs and distribution of the encephalic lesions in cattle affected by meningoencephalitis caused by bovine herpesvirus-5.] Epidemiologia, sinais clínicos e distribuição das lesões encefálicas em bovinos afetados por meningoencefalite por herpesvírus bovino-5. Pesquisa Veterinária Brasileira 26(2):123-132. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Seven outbreaks and an isolated case of meningoencephalitis caused by bovine herpesvirus-5 (BoHV-5) in cattle in Rio Grande do Sul, Brazil, occurring in 2002-2004, are described. From a total population at risk of 1,359 cattle, 54 1-18-month-old calves from both sexes and several breeds were affected and 50 died spontaneously or were euthanatized while moribund. The highest frequency of cases was in recently weaned calves or calves submitted to other stressing factors. General rates of morbidity, mortality and lethality were respectively 3.97, 3.67 and 92.59%. Clinical courses varied from 3-10 days and included depression, nasal and ocular discharge, grinding of teeth, circling, blindness, fever, nistagmus, trembling, anorexia, dysphagia, drooling, incoordination, head pressing, rough hair coat, tachycardia, tachypnea, abdominal pain, melena, falls, recumbency, opisthotonus, convulsions and paddling. Nineteen calves were necropsied. Necropsy findings were characterized by hyperemia of leptomeninges, swollen rostral portions of the telencephalon, and flattening of frontal lobes gyri; frequently in these frontal areas there were segmental brown-yellow discoloration and softening (malacia) of the cortex. In cases with more protracted clinical courses there were extensive swelling, softening and hemorrhaging of the telencephalic frontal lobes. Microscopically, all affected cattle had a necrotizing non-suppurative meningoencephalitis with variable distribution among the 19 cases and among the various telencephalic regions of the same case. The severity of these changes were more marked, in decreasing order of intensity, in the telencephalic frontal cortex, basal ganglia (nuclei), thalamus, brain stem, parietal telencephalic cortex, occipital telencephalic cortex and cerebellum. Perivascular inflammatory infiltrate consisted predominantly of lymphocytes, plasm cells, and less frequently of neutrophils. Additional microscopic findings included variable degrees of gliosis, edema, neuronal necrosis in the telencephalic cortex characterized by shrinking and eosinophilia of perikaria and nuclear picnosis (red neuron); basophilic intranuclear inclusion bodies in astrocytes and neurons (21.05% of the cases); sattelitosis; and neuronophagia. The areas of softening in the cortical substance consisted of necrosis of the neuroctodermal elements with maintenance of mesenchymal structures (vessels and microglia), infiltrate of Gitter cells, and, in more severe cases, extensive hemorrhages. In chronic cases, only vascular structures and a few Gitter cells remained in the cortical area leaving a cavity between white matter and leptomeninges (residual lesion).

• Bovine herpesvirus-5 BoHV-5 encephalitis diseases of cattle viral diseases neuropathology.

Abstract in Portuguese:

ABSTRACT.- Rissi D.R., Oliveira F.N., Rech R.R., Pierezan F., Lemos R.A.A. & Barros C.S.L. 2006. [Epidemiology, clinical signs and distribution of the encephalic lesions in cattle affected by meningoencephalitis caused by bovine herpesvirus-5.] Epidemiologia, sinais clínicos e distribuição das lesões encefálicas em bovinos afetados por meningoencefalite por herpesvírus bovino-5. Pesquisa Veterinária Brasileira 26(2):123-132. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Seven outbreaks and an isolated case of meningoencephalitis caused by bovine herpesvirus-5 (BoHV-5) in cattle in Rio Grande do Sul, Brazil, occurring in 2002-2004, are described. From a total population at risk of 1,359 cattle, 54 1-18-month-old calves from both sexes and several breeds were affected and 50 died spontaneously or were euthanatized while moribund. The highest frequency of cases was in recently weaned calves or calves submitted to other stressing factors. General rates of morbidity, mortality and lethality were respectively 3.97, 3.67 and 92.59%. Clinical courses varied from 3-10 days and included depression, nasal and ocular discharge, grinding of teeth, circling, blindness, fever, nistagmus, trembling, anorexia, dysphagia, drooling, incoordination, head pressing, rough hair coat, tachycardia, tachypnea, abdominal pain, melena, falls, recumbency, opisthotonus, convulsions and paddling. Nineteen calves were necropsied. Necropsy findings were characterized by hyperemia of leptomeninges, swollen rostral portions of the telencephalon, and flattening of frontal lobes gyri; frequently in these frontal areas there were segmental brown-yellow discoloration and softening (malacia) of the cortex. In cases with more protracted clinical courses there were extensive swelling, softening and hemorrhaging of the telencephalic frontal lobes. Microscopically, all affected cattle had a necrotizing non-suppurative meningoencephalitis with variable distribution among the 19 cases and among the various telencephalic regions of the same case. The severity of these changes were more marked, in decreasing order of intensity, in the telencephalic frontal cortex, basal ganglia (nuclei), thalamus, brain stem, parietal telencephalic cortex, occipital telencephalic cortex and cerebellum. Perivascular inflammatory infiltrate consisted predominantly of lymphocytes, plasm cells, and less frequently of neutrophils. Additional microscopic findings included variable degrees of gliosis, edema, neuronal necrosis in the telencephalic cortex characterized by shrinking and eosinophilia of perikaria and nuclear picnosis (red neuron); basophilic intranuclear inclusion bodies in astrocytes and neurons (21.05% of the cases); sattelitosis; and neuronophagia. The areas of softening in the cortical substance consisted of necrosis of the neuroctodermal elements with maintenance of mesenchymal structures (vessels and microglia), infiltrate of Gitter cells, and, in more severe cases, extensive hemorrhages. In chronic cases, only vascular structures and a few Gitter cells remained in the cortical area leaving a cavity between white matter and leptomeninges (residual lesion).

Abstract in English:

ABSTRACT.- Costa M.M., Silva M.S., Spricigo D.A., Witt N.M., Marchioro S.B., Kolling L. & Vargas A.P.C. 2006. [Epidemiology, molecular characterization and resistance to antimicrobials of Escherichia coli isolated from South-Brazilian pig herds.] Caracterização epidemiológica, molecular e perfil de resistência aos antimicrobianos de Escherichia coli isoladas de criatórios suínos do Sul do Brasil. Pesquisa Veterinária Brasileira 26(1):5-8. Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: agueda@ccr.ufsm.br Colibacillosis is an enteric disease with a major impact to the swine industry and is caused by enterotoxigenic strains of Escherichia coli. Forty clinical isolates from pigs with diarrhea and 13 environmental isolates were analysed regarding their genotypic profile, genetic relationship and antibiotic resistance. The most prevalent gene was Stb, identified in 50% of the isolates from clinical cases, and Sta and Lt were detected in 35% of them. Among the adesine factors investigated, F18 was found in 27.5% of the E. coli strains. The ERIC-PCR technique used for epidemiological characterization of the isolates did not show the expected discriminatory power. However, the test allowed separation of the isolates in groups, but did not evidence groups related to virulence factors. In the susceptibility test, the highest values for resistance were to tetracycline, in 88.6%. The index of multiple resistance to antimicrobials varied from 0 to 0.69.

• Escherichia coli genotypic profile resistance.

Abstract in Portuguese:

ABSTRACT.- Costa M.M., Silva M.S., Spricigo D.A., Witt N.M., Marchioro S.B., Kolling L. & Vargas A.P.C. 2006. [Epidemiology, molecular characterization and resistance to antimicrobials of Escherichia coli isolated from South-Brazilian pig herds.] Caracterização epidemiológica, molecular e perfil de resistência aos antimicrobianos de Escherichia coli isoladas de criatórios suínos do Sul do Brasil. Pesquisa Veterinária Brasileira 26(1):5-8. Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: agueda@ccr.ufsm.br Colibacillosis is an enteric disease with a major impact to the swine industry and is caused by enterotoxigenic strains of Escherichia coli. Forty clinical isolates from pigs with diarrhea and 13 environmental isolates were analysed regarding their genotypic profile, genetic relationship and antibiotic resistance. The most prevalent gene was Stb, identified in 50% of the isolates from clinical cases, and Sta and Lt were detected in 35% of them. Among the adesine factors investigated, F18 was found in 27.5% of the E. coli strains. The ERIC-PCR technique used for epidemiological characterization of the isolates did not show the expected discriminatory power. However, the test allowed separation of the isolates in groups, but did not evidence groups related to virulence factors. In the susceptibility test, the highest values for resistance were to tetracycline, in 88.6%. The index of multiple resistance to antimicrobials varied from 0 to 0.69.

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.