PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Carvalho N.M., Alonso L.A., Cunha T.G., Ravedutti J., Barros C.S.L. & Lemos R.A.A. 2006. [Poisoning of cattle by Tetrapterys multiglandulosa in Mato Grosso do Sul, Brazil.] Intoxicação de bovinos por Tetrapterys multiglandulosa (Malpighiaceae) em Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(3):139-146. Departamento de Medicina Veterinária, Universidade Federal de Mato Grosso do Sul, Avenida Senador Filinto Müller 2443, Caixa Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br Two outbreaks of poisoning by Tetrapterys multiglandulosa in cattle and the experimental reproduction of the toxicosis in sheep are described. Both outbreaks occurred on the same farm in the municipality of Bataiporã, state of Mato Grosso do Sul, Brazil. The first outbreak occurred in July-October 2004 and involved a cattle population at risk of 290 pregnant cows, which were introduced into a 60 hectare pasture with a legal reservation area heavily infested by T. multiglandulosa. Of these, 230 cows (79.3%) aborted, had stillbirths or delivered weak calves that died few days after birth. Seven cows died, and one cow and a 10-day-old calf were necropsied. The second outbreak occurred in September-October 2005, 40 days after 285 2-year-old heifers were introduced into the same pasture infested by T. multiglandulosa and where the first outbreak had occurred in the previous year. Nine heifers got sick and died, and three of then were necropsied. Clinical signs of affected cattle, including a 10-day-old calf, were marked lethargy, loss of weight with distension of the abdomen (ascites), subcutaneous dependant edema, distended and pulsating jugular veins, dyspnea and cardiac arrhythmia. Necropsy findings included a round and dilated heart with whitish and firm areas in the myocardium, and changes related to cardiac failure such as cavitary edema, nutmeg liver, pulmonary edema, a large blood clot in the left ventricle. Histopathological changes included necrosis and fibrosis in the myocardium, chronic passive hepatic centrolobular congestion, pulmonary edema, and spongy degeneration in the white matter of the brain. Experimental sheep died 29 (Sheep 1) and 35 (Sheep 2) days after being fed average daily doses of T. multiglandulosa corresponding to 14g/kg (Sheep 1) and 7,5 g/kg (Sheep 2) per day. Clinical signs were observed from the 7th day (Sheep1) and the 4th day (Sheep 2) of the experiment and included tachycardia, arrhythmia, lethargy and head pressing. Necropsy and histopathologic findings in both experimental sheep were very similar to those observed in affected cattle of the two spontaneous outbreaks.

• Poisonous plants Tetrapterys multiglandulosa Malpighiaceae plant poisoning cardiomiopathy abortion diseases of cattle pathology

Abstract in Portuguese:

ABSTRACT.- Carvalho N.M., Alonso L.A., Cunha T.G., Ravedutti J., Barros C.S.L. & Lemos R.A.A. 2006. [Poisoning of cattle by Tetrapterys multiglandulosa in Mato Grosso do Sul, Brazil.] Intoxicação de bovinos por Tetrapterys multiglandulosa (Malpighiaceae) em Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(3):139-146. Departamento de Medicina Veterinária, Universidade Federal de Mato Grosso do Sul, Avenida Senador Filinto Müller 2443, Caixa Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br Two outbreaks of poisoning by Tetrapterys multiglandulosa in cattle and the experimental reproduction of the toxicosis in sheep are described. Both outbreaks occurred on the same farm in the municipality of Bataiporã, state of Mato Grosso do Sul, Brazil. The first outbreak occurred in July-October 2004 and involved a cattle population at risk of 290 pregnant cows, which were introduced into a 60 hectare pasture with a legal reservation area heavily infested by T. multiglandulosa. Of these, 230 cows (79.3%) aborted, had stillbirths or delivered weak calves that died few days after birth. Seven cows died, and one cow and a 10-day-old calf were necropsied. The second outbreak occurred in September-October 2005, 40 days after 285 2-year-old heifers were introduced into the same pasture infested by T. multiglandulosa and where the first outbreak had occurred in the previous year. Nine heifers got sick and died, and three of then were necropsied. Clinical signs of affected cattle, including a 10-day-old calf, were marked lethargy, loss of weight with distension of the abdomen (ascites), subcutaneous dependant edema, distended and pulsating jugular veins, dyspnea and cardiac arrhythmia. Necropsy findings included a round and dilated heart with whitish and firm areas in the myocardium, and changes related to cardiac failure such as cavitary edema, nutmeg liver, pulmonary edema, a large blood clot in the left ventricle. Histopathological changes included necrosis and fibrosis in the myocardium, chronic passive hepatic centrolobular congestion, pulmonary edema, and spongy degeneration in the white matter of the brain. Experimental sheep died 29 (Sheep 1) and 35 (Sheep 2) days after being fed average daily doses of T. multiglandulosa corresponding to 14g/kg (Sheep 1) and 7,5 g/kg (Sheep 2) per day. Clinical signs were observed from the 7th day (Sheep1) and the 4th day (Sheep 2) of the experiment and included tachycardia, arrhythmia, lethargy and head pressing. Necropsy and histopathologic findings in both experimental sheep were very similar to those observed in affected cattle of the two spontaneous outbreaks.

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.- Jardim G.C., Pires P.P., Mathias L.A. & Ribeiro O.C. & Kuchembuck M.R.G. 2006. [Serological diagnosis of bovine brucellosis in adult herd vaccinated with Brucella abortus strain 19 reduced dose.] Diagnóstico sorológico da brucelose bovina em animais adultos vacinados com dose reduzida da cepa 19 de Brucella abortus. Pesquisa Veterinária Brasileira 26(3):177-182. Departamento de Medicina Veterinária, Universidade para o Desenvolvimento do Estado e Região do Pantanal (Uniderp), Rua Alexandre Herculano 1400, Parque dos Poderes, Campo Grande, MS 79037-280, Brazil. E-mail: gustavoj@mail.uniderp.br The study evaluated the use of a reduced dose of the Brucella abortus strain 19 vaccine, in an adult herd negative for the disease, by serological diagnostic techniques, advocated by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication, and by an indirect ELISA. The complement fixation test detecteed 46.77% positives, the rose bengal test 67.74%, the mercaptoethanol with standard agglutination test 87.09% and the ELISA ID 100%. The reduced dose influenced the serological diagnosis. None of the techniques reached a suitable specificity for use in the herd under those conditions, up to 3 months after vaccination.

• Bovine brucellosis vaccination strain 19 serological diagnosis

Abstract in Portuguese:

ABSTRACT.- Jardim G.C., Pires P.P., Mathias L.A. & Ribeiro O.C. & Kuchembuck M.R.G. 2006. [Serological diagnosis of bovine brucellosis in adult herd vaccinated with Brucella abortus strain 19 reduced dose.] Diagnóstico sorológico da brucelose bovina em animais adultos vacinados com dose reduzida da cepa 19 de Brucella abortus. Pesquisa Veterinária Brasileira 26(3):177-182. Departamento de Medicina Veterinária, Universidade para o Desenvolvimento do Estado e Região do Pantanal (Uniderp), Rua Alexandre Herculano 1400, Parque dos Poderes, Campo Grande, MS 79037-280, Brazil. E-mail: gustavoj@mail.uniderp.br The study evaluated the use of a reduced dose of the Brucella abortus strain 19 vaccine, in an adult herd negative for the disease, by serological diagnostic techniques, advocated by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication, and by an indirect ELISA. The complement fixation test detecteed 46.77% positives, the rose bengal test 67.74%, the mercaptoethanol with standard agglutination test 87.09% and the ELISA ID 100%. The reduced dose influenced the serological diagnosis. None of the techniques reached a suitable specificity for use in the herd under those conditions, up to 3 months after vaccination.

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.- Brocchi M., Ferreira A., Lancellotti M., Stehling E.G., Campos T.A., Nakazato G., Pestana de Castro A.F. & Silveira W.D. 2006. Typing of avian pathogenic Escherichia coli strains by REP-PCR. Pesquisa Veterinária Brasileira 26(2):69-73. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade de Campinas, Cx. Postal 6109, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br In the present study the repetitive extragenic palindromic (REP) polymerase chain reaction (PCR) technique was used to establish the clonal variability of 49 avian Escherichia coli (APEC) strains isolated from different outbreak cases of septicemia (n=24), swollen head syndrome (n=14) and omphalitis (n=11). Thirty commensal strains isolated from poultry with no signs of these illnesses were used as control strains. The purified DNA of these strains produced electrophoretic profiles ranging from 0 to 15 bands with molecular sizes varying from 100 bp to 6.1 kb, allowing the grouping of the 79 strains into a dendrogram containing 49 REP-types. Although REP-PCR showed good discriminating power it was not able to group the strains either into specific pathogenic classes or to differentiate between pathogenic and non-pathogenic strains. On the contrary, we recently demonstrated that other techniques such as ERIC-PCR and isoenzyme profiles are appropriate to discriminate between commensal and APEC strains and also to group these strains into specific pathogenic classes. In conclusion, REP-PCR seems to be a technique neither efficient nor universal for APEC strains discrimination. However, the population clonal structure obtained with the use of REP-PCR must not be ignored particularly if one takes into account that the APEC pathogenic mechanisms are not completely understood yet.

• Avian Escherichia coli typing REP-PCR.

Abstract in Portuguese:

Abstract.- Brocchi M., Ferreira A., Lancellotti M., Stehling E.G., Campos T.A., Nakazato G., Pestana de Castro A.F. & Silveira W.D. 2006. Typing of avian pathogenic Escherichia coli strains by REP-PCR. Pesquisa Veterinária Brasileira 26(2):69-73. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade de Campinas, Cx. Postal 6109, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br In the present study the repetitive extragenic palindromic (REP) polymerase chain reaction (PCR) technique was used to establish the clonal variability of 49 avian Escherichia coli (APEC) strains isolated from different outbreak cases of septicemia (n=24), swollen head syndrome (n=14) and omphalitis (n=11). Thirty commensal strains isolated from poultry with no signs of these illnesses were used as control strains. The purified DNA of these strains produced electrophoretic profiles ranging from 0 to 15 bands with molecular sizes varying from 100 bp to 6.1 kb, allowing the grouping of the 79 strains into a dendrogram containing 49 REP-types. Although REP-PCR showed good discriminating power it was not able to group the strains either into specific pathogenic classes or to differentiate between pathogenic and non-pathogenic strains. On the contrary, we recently demonstrated that other techniques such as ERIC-PCR and isoenzyme profiles are appropriate to discriminate between commensal and APEC strains and also to group these strains into specific pathogenic classes. In conclusion, REP-PCR seems to be a technique neither efficient nor universal for APEC strains discrimination. However, the population clonal structure obtained with the use of REP-PCR must not be ignored particularly if one takes into account that the APEC pathogenic mechanisms are not completely understood yet.

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.- Coimbra H.S., Fernandes C.G., Soares M.P., Meireles M.C.A., Radamés R. & Schuch L.F.D. 2006. [Equine monocytic Ehrlichiosis in Rio Grande do Sul: clinical, pathological and epidemiological aspects.] Ehrlichiose monocítica eqüina no Rio Grande do Sul: aspectos clínicos, anátomo-patológicos e epidemiológicos. Pesquisa Veterinária Brasileira 26(2):97-101. Laboratório de Doenças Infecciosas, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: bitoxu@ig.com.br A spontaneous outbreak of equine monocytic Ehrlichiosis (EME) is described. The disease occurred from November 2001 to February 2002 on a farm in the municipality of Arroio Grande, located at the western edge of the Mirim Lake, state of Rio Grande do Sul. Out of 50 horses 13 were affected and 6 died. The morbidity was 26% and the mortality 46.1%. The affected horses were 1-5 years old. The most important clinical sign was a profuse acute diarrhea. At necropsy of a horse that died with clinical signs of the disease, the main alterations were characterized by hemorrhagic areas of the mucosa of the large intestine with liquid contents, and congested and hemorrhagic areas alternating with normal areas as well as nodules with purulent secretion in the mucosa of the small intestine. The histological changes were characterized by moderate mononuclear infiltration of the mucosa, characterizing a lympho-histiocytic enteritis with predominance of macrophages. In the jejunum and ileum, related to the invagination of crypts and villi, a granulomatous enteritis was observed. To confirm the diagnosis of infection by Neorickettsia (Ehrlichia) risticii, blood samples of seven affected horses were taken and a polimerase chain reaction (PCR) was performed. Three tested blood samples were positive (42.8%) with observation of a band of 529pb characteristic of N. risticii.

• Neorickettsia (Ehrlichia) risticii equine monocytic Ehrlichiosis.

Abstract in Portuguese:

ABSTRACT.- Coimbra H.S., Fernandes C.G., Soares M.P., Meireles M.C.A., Radamés R. & Schuch L.F.D. 2006. [Equine monocytic Ehrlichiosis in Rio Grande do Sul: clinical, pathological and epidemiological aspects.] Ehrlichiose monocítica eqüina no Rio Grande do Sul: aspectos clínicos, anátomo-patológicos e epidemiológicos. Pesquisa Veterinária Brasileira 26(2):97-101. Laboratório de Doenças Infecciosas, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: bitoxu@ig.com.br A spontaneous outbreak of equine monocytic Ehrlichiosis (EME) is described. The disease occurred from November 2001 to February 2002 on a farm in the municipality of Arroio Grande, located at the western edge of the Mirim Lake, state of Rio Grande do Sul. Out of 50 horses 13 were affected and 6 died. The morbidity was 26% and the mortality 46.1%. The affected horses were 1-5 years old. The most important clinical sign was a profuse acute diarrhea. At necropsy of a horse that died with clinical signs of the disease, the main alterations were characterized by hemorrhagic areas of the mucosa of the large intestine with liquid contents, and congested and hemorrhagic areas alternating with normal areas as well as nodules with purulent secretion in the mucosa of the small intestine. The histological changes were characterized by moderate mononuclear infiltration of the mucosa, characterizing a lympho-histiocytic enteritis with predominance of macrophages. In the jejunum and ileum, related to the invagination of crypts and villi, a granulomatous enteritis was observed. To confirm the diagnosis of infection by Neorickettsia (Ehrlichia) risticii, blood samples of seven affected horses were taken and a polimerase chain reaction (PCR) was performed. Three tested blood samples were positive (42.8%) with observation of a band of 529pb characteristic of N. risticii.

Abstract in English:

ABSTRACT.- Aguiar D.M, Gennari S.M., Cavalcante G.T., Labruna M.B., Vasconcellos S.A., Rodrigues A.A.R., Moraes Z.M. & Camargo L.M.A. 2006. Seroprevalence of Leptospira spp in cattle from Monte Negro municipality, western Amazon. Pesquisa Veterinária Brasileira 26(2):102-104. Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine and Animal Production, University of São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. E-mail: danmoura@aptaregional.sp.gov.br The prevalence of anti-Leptospira spp antibodies was investigated in 2,109 female cattle from 86 herds of Monte Negro municipality, Rondônia, Brazil. Sera samples were evaluated by Microscopic Agglutination Test against 24 leptospira serovars. Titers =100 for at least one of 24 leptospira serovars were detected in 1,114 cows (52.8%) from 82 (95.3%) herds. The adjusted overall prevalence for Monte Negro municipality was 53.9% (49-58.7%; CI: 95%). The most prevalent serovars were Hardjo (14.5%), Wolffi (12.3%), Shermani (10.8%), Patoc (7.9%), and Hebdomadis (6.1%). Other serovars worldwidely reported like Bratislava, Pomona and Grippotyphosa were detected in low levels.

• Leptospira spp cattle epidemiology Amazon.

Abstract in Portuguese:

ABSTRACT.- Aguiar D.M, Gennari S.M., Cavalcante G.T., Labruna M.B., Vasconcellos S.A., Rodrigues A.A.R., Moraes Z.M. & Camargo L.M.A. 2006. Seroprevalence of Leptospira spp in cattle from Monte Negro municipality, western Amazon. Pesquisa Veterinária Brasileira 26(2):102-104. Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine and Animal Production, University of São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. E-mail: danmoura@aptaregional.sp.gov.br The prevalence of anti-Leptospira spp antibodies was investigated in 2,109 female cattle from 86 herds of Monte Negro municipality, Rondônia, Brazil. Sera samples were evaluated by Microscopic Agglutination Test against 24 leptospira serovars. Titers =100 for at least one of 24 leptospira serovars were detected in 1,114 cows (52.8%) from 82 (95.3%) herds. The adjusted overall prevalence for Monte Negro municipality was 53.9% (49-58.7%; CI: 95%). The most prevalent serovars were Hardjo (14.5%), Wolffi (12.3%), Shermani (10.8%), Patoc (7.9%), and Hebdomadis (6.1%). Other serovars worldwidely reported like Bratislava, Pomona and Grippotyphosa were detected in low levels.

Abstract in English:

ABSTRACT.- Moreira Souto M.A., Kommers G.D., Barros C.S.L., Piazer J.V.M., Rech R.R., Riet-Correa F. & Schild A.L. 2006. [Neoplasms of the upper digestive tract of cattle associated with spontaneous ingestion of bracken fern (Pteridium aquilinum).] Neoplasias do trato alimentar superior de bovinos associadas ao consumo espontâneo de samambaia (Pteridium aquilinum). Pesquisa Veterinária Brasileira 26(2):112-122. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: glaukommers@yahoo.com Thirty bovine with neoplasms of the upper digestive tract (UDT) associated with spontaneous ingestion of bracken fern (Pteridium aquilinum) were studied. They were from 27 farms, located in the municipalities of Jaguari (23) and Nova Esperança do Sul (4), Rio Grande do Sul, Brazil. The total cattle population in those farms was 1,090 and large amounts of bracken fern were found in the pastures. Twenty-six of the affected cattle were cows and four were castrated males, 3-13 years of age; most of them were 7-8 years old (46,6%). Clinical signs observed in the affected animals were progressive weight loss, absence of ruminal movements, cough, dysphagia, regurgitation, halitosis, diarrhea, and bloat. Less frequent signs were selective appetite, dyspnea, and salivation. Two bovine died and 28 were submitted to euthanasia in advanced stage of disease and necropsied. The main gross and microscopic alterations were found in identical areas of the UDT. They consisted of papillomas, transforming papillomas, and squamous cell carcinomas (SCCs). Metastases of SCCs to regional lymph nodes and other organs, such as liver and lungs, were also observed (18/30). Twenty-nine bovine had papillomas of various sizes in several areas of the UDT. The digestive papillomatosis ranged from mild (45%), to moderate (38%), to severe (17%). Three developing phases were observed microscopically in the examined papillomas: an early growing phase, a developing phase, and a regressing phase. In 16 cases, there was malignant transformation of papillomas into SCCs. The SCCs were solitary (12/30) or multiple (18/30) and were histologically well, moderately, or poorly differentiated. Grouping the distribution of SCCs of larger extension in the UDT into cranial region (base of the tongue, pharynx/oropharynx, and epiglottis), medial region (esophagus), and caudal region (cardia and rumen), the distribution was cranial in 39%, middle in 16%, and caudal in 45% of the cases. By the same grouping criteria, but considering the total number of times SCCs of varied extensions were diagnosed in the cranial, middle, and caudal regions, the percentages changed to 34%, 26%, and 40%, respectively. The epidemiological and histomorphological evidences found in this study are in agreement with the observations that point out the co-carcinogenesis between bovine papillomavirus type 4 infection and chemicals of bracken fern in the pathogenesis of the SCCs in the UDT of cattle. However, the presence of pre-neoplastic changes and SCCs in situ or in early stages of development, independently of the presence of papillomas, clearly indicates the possibility of development of SCCs from normal epithelium, probably due to the direct action of the chemical carcinogens contained in bracken fern.

• Poisonous plants Pteridium aquilinum plant poisoning bovine papillomavirus type 4 squamous cell carcinoma diseases of cattle pathology.

Abstract in Portuguese:

ABSTRACT.- Moreira Souto M.A., Kommers G.D., Barros C.S.L., Piazer J.V.M., Rech R.R., Riet-Correa F. & Schild A.L. 2006. [Neoplasms of the upper digestive tract of cattle associated with spontaneous ingestion of bracken fern (Pteridium aquilinum).] Neoplasias do trato alimentar superior de bovinos associadas ao consumo espontâneo de samambaia (Pteridium aquilinum). Pesquisa Veterinária Brasileira 26(2):112-122. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: glaukommers@yahoo.com Thirty bovine with neoplasms of the upper digestive tract (UDT) associated with spontaneous ingestion of bracken fern (Pteridium aquilinum) were studied. They were from 27 farms, located in the municipalities of Jaguari (23) and Nova Esperança do Sul (4), Rio Grande do Sul, Brazil. The total cattle population in those farms was 1,090 and large amounts of bracken fern were found in the pastures. Twenty-six of the affected cattle were cows and four were castrated males, 3-13 years of age; most of them were 7-8 years old (46,6%). Clinical signs observed in the affected animals were progressive weight loss, absence of ruminal movements, cough, dysphagia, regurgitation, halitosis, diarrhea, and bloat. Less frequent signs were selective appetite, dyspnea, and salivation. Two bovine died and 28 were submitted to euthanasia in advanced stage of disease and necropsied. The main gross and microscopic alterations were found in identical areas of the UDT. They consisted of papillomas, transforming papillomas, and squamous cell carcinomas (SCCs). Metastases of SCCs to regional lymph nodes and other organs, such as liver and lungs, were also observed (18/30). Twenty-nine bovine had papillomas of various sizes in several areas of the UDT. The digestive papillomatosis ranged from mild (45%), to moderate (38%), to severe (17%). Three developing phases were observed microscopically in the examined papillomas: an early growing phase, a developing phase, and a regressing phase. In 16 cases, there was malignant transformation of papillomas into SCCs. The SCCs were solitary (12/30) or multiple (18/30) and were histologically well, moderately, or poorly differentiated. Grouping the distribution of SCCs of larger extension in the UDT into cranial region (base of the tongue, pharynx/oropharynx, and epiglottis), medial region (esophagus), and caudal region (cardia and rumen), the distribution was cranial in 39%, middle in 16%, and caudal in 45% of the cases. By the same grouping criteria, but considering the total number of times SCCs of varied extensions were diagnosed in the cranial, middle, and caudal regions, the percentages changed to 34%, 26%, and 40%, respectively. The epidemiological and histomorphological evidences found in this study are in agreement with the observations that point out the co-carcinogenesis between bovine papillomavirus type 4 infection and chemicals of bracken fern in the pathogenesis of the SCCs in the UDT of cattle. However, the presence of pre-neoplastic changes and SCCs in situ or in early stages of development, independently of the presence of papillomas, clearly indicates the possibility of development of SCCs from normal epithelium, probably due to the direct action of the chemical carcinogens contained in bracken fern.