PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Corrêa A.M.R., Bezerra P.S.J., Pavarini S.P., Santos A.S., Sonne L., Zlotowski P., Gomes G. & Driemeier D. 2008. Senecio brasiliensis (Asteraceae) poisoning in Murrah buffaloes in Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(3):187-189. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Thirteen (14.4%) out of 90 Murrah buffaloes (Bubalus bubalis) became ill after con-sumption of Senecio brasiliensis, and 11 (12.2%) of them died. The buffaloes were kept in a highly Senecio brasiliensis infested area. The poisoning occurred in June-August 2006 on a farm in the county of Nova Prata, Rio Grande do Sul, southern Brazil. Clinical signs included weakness, apathy, progressive weight loss, permanent decubitus, and diarrhea. Necropsy was performed in 2 of the 11 buffaloes that died. The pathological findings were typical of poisoning by pyrrolizidine alkaloids. High infestation of pastures with S. brasiliensis, severe drought, and consequent starvation were the main epidemiological factors associated with the poisoning here described.

• Buffaloes pyrrolizidine alkaloids Senecio poisoning

Abstract in Portuguese:

ABSTRACT.- Corrêa A.M.R., Bezerra P.S.J., Pavarini S.P., Santos A.S., Sonne L., Zlotowski P., Gomes G. & Driemeier D. 2008. Senecio brasiliensis (Asteraceae) poisoning in Murrah buffaloes in Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(3):187-189. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Thirteen (14.4%) out of 90 Murrah buffaloes (Bubalus bubalis) became ill after con-sumption of Senecio brasiliensis, and 11 (12.2%) of them died. The buffaloes were kept in a highly Senecio brasiliensis infested area. The poisoning occurred in June-August 2006 on a farm in the county of Nova Prata, Rio Grande do Sul, southern Brazil. Clinical signs included weakness, apathy, progressive weight loss, permanent decubitus, and diarrhea. Necropsy was performed in 2 of the 11 buffaloes that died. The pathological findings were typical of poisoning by pyrrolizidine alkaloids. High infestation of pastures with S. brasiliensis, severe drought, and consequent starvation were the main epidemiological factors associated with the poisoning here described.

Abstract in English:

ABSTRACT.- Rodrigues A., De La Corte F.D., Graça D.L., Rissi D.R., Schild A.L., Kommers G.D. & Barros C.S.L. 2008. [Stringhalt in horses from the state of Rio Grande do Sul, Brazil.] Harpejamento em eqüinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(1):23-28. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical, gross and histological findings of cases of stringhalt occurring in horses from eight farms in six counties in the State of Rio Grande do Sul, Brazil from 2000-2005 are reported. At least 10 horses were affected. Ages of affected horses were 1-13 years (average 6.2 years) and 1-2 horses were affected in each farm. Factors that might have influenced the appearance of the disease included dearth of forage due to insufficient rainfall. The presence of the plant Hypochaeris radicata, often implicated as a cause of stringhalt in horses, was observed in the pasture of three out of five evaluated farms and in six of these farms the pasture was poor due to scarse precipitation. Estimated morbidity was 17.3% and lethality was close to zero although two horses were euthanatized for necropsy. Characteristic clinical signs included excessive flexion of the stifle and hock joints, impaired ambulation and bunny hop-type of gait. Clinical disease was graded by number scores from 1-5, higher numbers indicating increasing severity. Three horses were graded as 1, one horse as 2, three horses as 3, one horse as 4 and two horses as 5. Treatment with phenytoin in two horses and with phenytoin and tenectomy in another one did not result in amelioration of the clinical signs. Four out of ten clinical examined horses with stringhalt recovered with no treatment within 2-4 months of clinical disease and four affected horses did not recover even after 9-17 months of clinical disease, when they were lastly examined. Necropsy findings included atrophy of skeletal muscle of the large muscular groups which was confirmed histologically. Histological evaluation of peripheral nerves of one of the euthanatized horses revealed reduction or absence of myelinated fibers. Ultrastructural findings included signs of demyelination, regeneration and remyelination of peripheral nerves.

• Neuropathy toxic neuropathy diseases of horses

Abstract in Portuguese:

ABSTRACT.- Rodrigues A., De La Corte F.D., Graça D.L., Rissi D.R., Schild A.L., Kommers G.D. & Barros C.S.L. 2008. [Stringhalt in horses from the state of Rio Grande do Sul, Brazil.] Harpejamento em eqüinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(1):23-28. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical, gross and histological findings of cases of stringhalt occurring in horses from eight farms in six counties in the State of Rio Grande do Sul, Brazil from 2000-2005 are reported. At least 10 horses were affected. Ages of affected horses were 1-13 years (average 6.2 years) and 1-2 horses were affected in each farm. Factors that might have influenced the appearance of the disease included dearth of forage due to insufficient rainfall. The presence of the plant Hypochaeris radicata, often implicated as a cause of stringhalt in horses, was observed in the pasture of three out of five evaluated farms and in six of these farms the pasture was poor due to scarse precipitation. Estimated morbidity was 17.3% and lethality was close to zero although two horses were euthanatized for necropsy. Characteristic clinical signs included excessive flexion of the stifle and hock joints, impaired ambulation and bunny hop-type of gait. Clinical disease was graded by number scores from 1-5, higher numbers indicating increasing severity. Three horses were graded as 1, one horse as 2, three horses as 3, one horse as 4 and two horses as 5. Treatment with phenytoin in two horses and with phenytoin and tenectomy in another one did not result in amelioration of the clinical signs. Four out of ten clinical examined horses with stringhalt recovered with no treatment within 2-4 months of clinical disease and four affected horses did not recover even after 9-17 months of clinical disease, when they were lastly examined. Necropsy findings included atrophy of skeletal muscle of the large muscular groups which was confirmed histologically. Histological evaluation of peripheral nerves of one of the euthanatized horses revealed reduction or absence of myelinated fibers. Ultrastructural findings included signs of demyelination, regeneration and remyelination of peripheral nerves.

Abstract in English:

ABSTRACT.- Rissi D.R., Rech R.R., Pierezan F., Gabriel A.L., Trost M.E., Brum J.S., Kommers G.D. & Barros C.S.L. 2007. [Plant and plant-associated mycotoxins poisoning in cattle in Rio Grande do Sul, Brazil: 461 cases.] Intoxicações por plantas e micotoxinas associadas a plantas em bovinos no Rio Grande do Sul: 461 casos. Pesquisa Veterinária Brasileira 27(7):261-268. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br From 1990 to 2005, tissues from 2,912 cattle necropsies were examined at the Laboratory of Veterinary Pathology (LPV) of the Federal University of Santa Maria (UFSM), Brazil. These tissues came from necropsies performed by faculty members of the LPV or were mailed-in samples from necropsy performed by veterinarian practitioners. In 461 (15.83%) of these necropsies the cause of death was attributed to the ingestion of poisonous plants. In decreasing order of frequency poisoning by the following plants were registered: Senecio spp (56.14%), Pteridium aquilinum (12.06%), Ateleia glazioviana (10.31%), Solanum fastigiatum (5.04%), Baccharis coridifolia (3.29%), Xanthium cavanillesii (3.07%), Senna occidentalis (2.63%), Ramaria flavo-brunnescens (2.41%), Amaranthus spp (2.19%), Vicia villosa (1.54%), Ipomoea batatas, Prunus sellowii, cytrus pulp (0.44% each), Cestrum parqui, Claviceps paspali, Claviceps purpurea, Brachiaria spp and Lantana sp (0.22% each). In a given outbreak the number of affected cattle was substantially higher than the number of necropsies performed. The following aspects are discussed for each plant: geographical distribution; factors inducing ingestion; morbidity, mortality and lethality rates, clinical signs, necropsy findings, histopathology. For those plants in which information on the active principle and pathogenesis are available, these aspects are included in the discussion.

• Poisonous plants epidemiology cattle diseases

Abstract in Portuguese:

ABSTRACT.- Rissi D.R., Rech R.R., Pierezan F., Gabriel A.L., Trost M.E., Brum J.S., Kommers G.D. & Barros C.S.L. 2007. [Plant and plant-associated mycotoxins poisoning in cattle in Rio Grande do Sul, Brazil: 461 cases.] Intoxicações por plantas e micotoxinas associadas a plantas em bovinos no Rio Grande do Sul: 461 casos. Pesquisa Veterinária Brasileira 27(7):261-268. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br From 1990 to 2005, tissues from 2,912 cattle necropsies were examined at the Laboratory of Veterinary Pathology (LPV) of the Federal University of Santa Maria (UFSM), Brazil. These tissues came from necropsies performed by faculty members of the LPV or were mailed-in samples from necropsy performed by veterinarian practitioners. In 461 (15.83%) of these necropsies the cause of death was attributed to the ingestion of poisonous plants. In decreasing order of frequency poisoning by the following plants were registered: Senecio spp (56.14%), Pteridium aquilinum (12.06%), Ateleia glazioviana (10.31%), Solanum fastigiatum (5.04%), Baccharis coridifolia (3.29%), Xanthium cavanillesii (3.07%), Senna occidentalis (2.63%), Ramaria flavo-brunnescens (2.41%), Amaranthus spp (2.19%), Vicia villosa (1.54%), Ipomoea batatas, Prunus sellowii, cytrus pulp (0.44% each), Cestrum parqui, Claviceps paspali, Claviceps purpurea, Brachiaria spp and Lantana sp (0.22% each). In a given outbreak the number of affected cattle was substantially higher than the number of necropsies performed. The following aspects are discussed for each plant: geographical distribution; factors inducing ingestion; morbidity, mortality and lethality rates, clinical signs, necropsy findings, histopathology. For those plants in which information on the active principle and pathogenesis are available, these aspects are included in the discussion.

Abstract in English:

ABSTRACT.- Almeida M.B., Tortelli F.P., Riet-Correa B., Ferreira J.L.M., Soares M.P., Farias N.A.R., Riet-Correa F. & Schild A.L. 2006. [Tick fever in southern Brazil: a retrospective study of 1978-2005.] Tristeza parasitária bovina na região sul do Rio Grande do Sul: estudo retrospectivo de 1978-2005. Pesquisa Veterinária Brasileira 26(4):236-242. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br A retrospective study of tick fever was made, which occurred from 1978-2005 in southern Rio Grande do Sul in the influence area of the Regional Diagnostic Laboratory of the Federal University of Pelotas. From 4,884 cattle specimens, sent by practitioners or which were from necropsies performed at the Diagnostic Laboratory, 231 (4.7%) were diagnosed as tick fever. Data from 221 of those outbreaks were analyzed. Ninety one (41.1%) outbreaks were caused by Babesia bovis, 11 (4.9%) by Babesia bigemina, and 65 (29.41%) by Anaplasma marginale. In other 33 (14.93%) outbreaks of babesiosis there is no information if the disease was caused by B. bovis or B. bigemina, and 21 (9.5%) outbreaks were caused by mixed infection of A. marginale and B. bovis or B. bigemina. Mean morbidity, mortality, and letality rates in 149 outbreaks were 11.17%, 6.81%, and 70.04%, respectively. Most outbreaks occurred during summer (January-March) and autumn (April-June), mainly in 1 to 3-year-old cattle. Clinical signs were depression, weakness, fallen ears, fever, and weight loss. Low packed cell volume values were always found. Hemoglobinury was observed in babesiosis. Neurological signs characterized by gait alterations, muscular tremors, aggressiveness and falling down with tonic and clonic convulsions were observed in babesiosis by B. bovis. The main gross lesions were anemia, jaundice, splenomegaly, hepatomegaly, yellow liver and cardiac hemorrhages. Hemoglobinury was observed in babesiosis, and congestion of the cerebral cortex in babesiosis by B. bovis. It is concluded that B. bovis is the main agent causing thick fever in southern Rio Grande do Sul. In that region with a cattle population of 2,630,000 heads the annual losses due to tick fever can be estimated in 6,220 cattle or US$ 1,623,000.00. Preventive measures to diminish tick fever losses in the region are necessary.

• Parasitic diseases tick fever epidemiology Babesia bovis Babesia bigemina Anaplasma marginale

Abstract in Portuguese:

ABSTRACT.- Almeida M.B., Tortelli F.P., Riet-Correa B., Ferreira J.L.M., Soares M.P., Farias N.A.R., Riet-Correa F. & Schild A.L. 2006. [Tick fever in southern Brazil: a retrospective study of 1978-2005.] Tristeza parasitária bovina na região sul do Rio Grande do Sul: estudo retrospectivo de 1978-2005. Pesquisa Veterinária Brasileira 26(4):236-242. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br A retrospective study of tick fever was made, which occurred from 1978-2005 in southern Rio Grande do Sul in the influence area of the Regional Diagnostic Laboratory of the Federal University of Pelotas. From 4,884 cattle specimens, sent by practitioners or which were from necropsies performed at the Diagnostic Laboratory, 231 (4.7%) were diagnosed as tick fever. Data from 221 of those outbreaks were analyzed. Ninety one (41.1%) outbreaks were caused by Babesia bovis, 11 (4.9%) by Babesia bigemina, and 65 (29.41%) by Anaplasma marginale. In other 33 (14.93%) outbreaks of babesiosis there is no information if the disease was caused by B. bovis or B. bigemina, and 21 (9.5%) outbreaks were caused by mixed infection of A. marginale and B. bovis or B. bigemina. Mean morbidity, mortality, and letality rates in 149 outbreaks were 11.17%, 6.81%, and 70.04%, respectively. Most outbreaks occurred during summer (January-March) and autumn (April-June), mainly in 1 to 3-year-old cattle. Clinical signs were depression, weakness, fallen ears, fever, and weight loss. Low packed cell volume values were always found. Hemoglobinury was observed in babesiosis. Neurological signs characterized by gait alterations, muscular tremors, aggressiveness and falling down with tonic and clonic convulsions were observed in babesiosis by B. bovis. The main gross lesions were anemia, jaundice, splenomegaly, hepatomegaly, yellow liver and cardiac hemorrhages. Hemoglobinury was observed in babesiosis, and congestion of the cerebral cortex in babesiosis by B. bovis. It is concluded that B. bovis is the main agent causing thick fever in southern Rio Grande do Sul. In that region with a cattle population of 2,630,000 heads the annual losses due to tick fever can be estimated in 6,220 cattle or US$ 1,623,000.00. Preventive measures to diminish tick fever losses in the region are necessary.

Abstract in English:

ABSTRACT.- Corrêa A.M.R., Zlotowski P., Rozza D.B., Borba M.R., Leal J.S., Cuz C.E.F. & Driemeier D. 2006. Postweaning multisystemic wasting syndrome in farmed wild boars (Sus scrofa) in Rio Grande do Sul. Pesquisa Veterinária Brasileira 26(3):154-156. Department of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpath@ufrgs.br This report concerns an outbreak of postweaning multisystemic wasting syndrome in wild boars from commercial herds in Rio Grande do Sul, Brazil. The main clinical signs were progressive wasting, respiratory distress, diarrhea, and ocular discharges. Enhanced lymph nodes and spleens, ascites, hydrothorax, and non collapsed lungs were the principal gross lesions. Varying degrees of lymphohistiocytic infiltrates in lymph nodes, spleen, and intestines were the most significant microscopic changes. Although a total of 26 animals had showed clinical and pathological findings consistent with the disease, only in 11 of them it was possible to confirm a PMWS diagnosis through the association of specific lesions in lymphoid tissues with the presence of the viral antigen detected by immunohistochemistry. These findings were similar to those reported in the swine disease.

• Circovirus PCV2 PMWS immunohistochemistry wild boar Sus scrofa

Abstract in Portuguese:

ABSTRACT.- Corrêa A.M.R., Zlotowski P., Rozza D.B., Borba M.R., Leal J.S., Cuz C.E.F. & Driemeier D. 2006. Postweaning multisystemic wasting syndrome in farmed wild boars (Sus scrofa) in Rio Grande do Sul. Pesquisa Veterinária Brasileira 26(3):154-156. Department of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpath@ufrgs.br This report concerns an outbreak of postweaning multisystemic wasting syndrome in wild boars from commercial herds in Rio Grande do Sul, Brazil. The main clinical signs were progressive wasting, respiratory distress, diarrhea, and ocular discharges. Enhanced lymph nodes and spleens, ascites, hydrothorax, and non collapsed lungs were the principal gross lesions. Varying degrees of lymphohistiocytic infiltrates in lymph nodes, spleen, and intestines were the most significant microscopic changes. Although a total of 26 animals had showed clinical and pathological findings consistent with the disease, only in 11 of them it was possible to confirm a PMWS diagnosis through the association of specific lesions in lymphoid tissues with the presence of the viral antigen detected by immunohistochemistry. These findings were similar to those reported in the swine disease.

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:

Corrêa A.M.R., Pescador C.A., Schmitz M., Zlotowski P., Rozza D.B., Oliveira E.C., Barcellos D.E. & Driemeier D. 2006. [Clinical and pathological aspects of swine circovirosis in Rio Grande do Sul, southern Brazil.] Aspectos clínico-patológicos associados à circovirose suína no Rio Grande do Sul. Pesquisa Veterinária Brasileira 26(1):9-13. Setor de Patologia Veterinária, Faculdade de Veterinária, UFRGS, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br A total of 97 pigs, which had presented wasting, lymphadenomegaly, respiratory distress and pale or icteric mucosa, was necropsied over a 6-month period. Macroscopic lesions were characterized mostly by enlarged lymph nodes, non collapsed and round edged lungs with cranio-ventral areas of consolidation and interlobular edema. Kidneys had increased size, were pale, and presented numerous scattered white spots projecting from surface to the cortical area. Some kidneys also showed small red spots similar to petechial hemorrhage over the cortex. Main microscopic lesions were lympho-histiocytic infiltration in lymph nodes, lungs, and kidneys. Immunohistochemical probing with polyclonal antisera to type II swine circovirus stained positively in 50 out of the 56 cases tested (89.2%).

• Circovirus PMWS PCV2 immunohistochemistry swine.

Abstract in Portuguese:

Corrêa A.M.R., Pescador C.A., Schmitz M., Zlotowski P., Rozza D.B., Oliveira E.C., Barcellos D.E. & Driemeier D. 2006. [Clinical and pathological aspects of swine circovirosis in Rio Grande do Sul, southern Brazil.] Aspectos clínico-patológicos associados à circovirose suína no Rio Grande do Sul. Pesquisa Veterinária Brasileira 26(1):9-13. Setor de Patologia Veterinária, Faculdade de Veterinária, UFRGS, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br A total of 97 pigs, which had presented wasting, lymphadenomegaly, respiratory distress and pale or icteric mucosa, was necropsied over a 6-month period. Macroscopic lesions were characterized mostly by enlarged lymph nodes, non collapsed and round edged lungs with cranio-ventral areas of consolidation and interlobular edema. Kidneys had increased size, were pale, and presented numerous scattered white spots projecting from surface to the cortical area. Some kidneys also showed small red spots similar to petechial hemorrhage over the cortex. Main microscopic lesions were lympho-histiocytic infiltration in lymph nodes, lungs, and kidneys. Immunohistochemical probing with polyclonal antisera to type II swine circovirus stained positively in 50 out of the 56 cases tested (89.2%).

Abstract in English:

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

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

Abstract in Portuguese:

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

Abstract in English:

Rech R.R., Schild A.L., Driemeier D., Garmatz S.L., Oliveira F.N., Riet-Correa F. & Barros C.S.L. 2005. [Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: Epidemiology, clinical signs and pathology.] Febre catarral maligna em bovinos no Rio Grande do Sul: epidemiologia, sinais clínicos e patologia. Pesquisa Veterinária Brasileira 25(2):97-105. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical signs, necropsy and histopathological findings in cases of malignant catarrhal fever (MCF) occurring in cattle from 15 farms in Rio Grande do Sul, Brazil, from 1973 to 2003, are described. In 9 instances (60%) the disease occurred as sporadic cases affecting 1-3 cattle whereas in six farms (40%) MCF occurred as epizootics involving several cattle in each affected herd. Morbidity rates ranged from 2.4% to 20% and lethality rates were 83.3% and 100%. Cattle of all ages and both sexes were affected. Where the information was available (9 farms) sheep were in contact with affected cattle and cases of MCF occurred more frequently in spring and summer. Clinical courses were acute or subacute and clinical signs included fever, nasal and ocular discharges, conjunctivitis, drooling, hematuria, necrosis and blunting of buccal papillae, enlargement of lymph nodes, diarrhea and neurological disturbances. Necropsy findings included opaque corneas, reddening, erosions and ulcerations in several mucous membranes of the alimentary, respiratory and urogenital tracts, and the conjunctiva; enlargement and haemorrhage of lymph nodes and multiple white foci in the renal cortices and in the hepatic portal triads. Crustous dermatitis was observed in some cases. Main histopathological findings included vasculitis, necrosis of the surface epithelia and accumulation of inflammatory cells in several organs. Vasculitis were associated with fibrinoid necrosis of the medial layer of arteries and inflammatory cells included lymphoblasts, lymphocytes, plasma cells and macrophages.

• Infectious diseases epidemiology viral diseases diseases of cattle pathology.

Abstract in Portuguese:

Rech R.R., Schild A.L., Driemeier D., Garmatz S.L., Oliveira F.N., Riet-Correa F. & Barros C.S.L. 2005. [Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: Epidemiology, clinical signs and pathology.] Febre catarral maligna em bovinos no Rio Grande do Sul: epidemiologia, sinais clínicos e patologia. Pesquisa Veterinária Brasileira 25(2):97-105. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical signs, necropsy and histopathological findings in cases of malignant catarrhal fever (MCF) occurring in cattle from 15 farms in Rio Grande do Sul, Brazil, from 1973 to 2003, are described. In 9 instances (60%) the disease occurred as sporadic cases affecting 1-3 cattle whereas in six farms (40%) MCF occurred as epizootics involving several cattle in each affected herd. Morbidity rates ranged from 2.4% to 20% and lethality rates were 83.3% and 100%. Cattle of all ages and both sexes were affected. Where the information was available (9 farms) sheep were in contact with affected cattle and cases of MCF occurred more frequently in spring and summer. Clinical courses were acute or subacute and clinical signs included fever, nasal and ocular discharges, conjunctivitis, drooling, hematuria, necrosis and blunting of buccal papillae, enlargement of lymph nodes, diarrhea and neurological disturbances. Necropsy findings included opaque corneas, reddening, erosions and ulcerations in several mucous membranes of the alimentary, respiratory and urogenital tracts, and the conjunctiva; enlargement and haemorrhage of lymph nodes and multiple white foci in the renal cortices and in the hepatic portal triads. Crustous dermatitis was observed in some cases. Main histopathological findings included vasculitis, necrosis of the surface epithelia and accumulation of inflammatory cells in several organs. Vasculitis were associated with fibrinoid necrosis of the medial layer of arteries and inflammatory cells included lymphoblasts, lymphocytes, plasma cells and macrophages.

Abstract in English:

D'Ávila da Silva A., Sortica V.A., Braga A.C., Spilki F.R., Franco A.C., Esteves P.A., Rijsewijk F., Rosa J.C.A., Batista H.B.C.R., Oliveira A.P. & Roehe P.M. 2005. [Antigenic and molecular characterization of eight samples of Aujeszky’s disease virus isolated in the state of Rio Grande do Sul, Brazil, in 2003.] Caracterização antigênica e molecular de oito amostras do virus da doença de Aujeszky isoladas no estado do Rio Grande do Sul em 2003. Pesquisa Veterinária Brasileira 25(1):21-24. Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Fepagro Saúde Animal, Estrada do Conde 6000, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br Pseudorabies or Aujeszky’s disease (AD), caused by pseudorabies virus (PRV) is a major concern in swine production. In the state of Rio Grande do Sul, Brazil, AD was only detected in 1954, in cattle. In 2003 two outbreaks of encephalitis occurred on the northern region of the state, close to the border with the state of Santa Catarina. Pseudorabies virus (PRV) was isolated from distinct farms within the region and subjected to antigenic and genomic analyses. These isolates were compared with prototype strains NIA-3 and NP. Antigenic characterization with a panel of monoclonal antibodies (Mabs) directed to viral glycoproteins (gB, gC, gD and gE,) was performed by an imunoperoxidase monolayer assay (IPMA) on infected cell monolayers. Genomic characterization was carried out by restriction enzyme analysis (REA) of the whole DNA viral genome with Bam HI. The antigenic profile of the eight isolates from Rio Grande do Sul as well as strains NIA-3 and NP were similar. REA analysis revealed that all isolates from Rio Grande do Sul displayed a genomic type II arrangement, a genotype often found in other outbreaks of AD previously reported in other Brazilian states. The results obtained suggest that the eight isolates examined here were similar.

• Aujeszky's disease epidemiology.

Abstract in Portuguese:

D'Ávila da Silva A., Sortica V.A., Braga A.C., Spilki F.R., Franco A.C., Esteves P.A., Rijsewijk F., Rosa J.C.A., Batista H.B.C.R., Oliveira A.P. & Roehe P.M. 2005. [Antigenic and molecular characterization of eight samples of Aujeszky’s disease virus isolated in the state of Rio Grande do Sul, Brazil, in 2003.] Caracterização antigênica e molecular de oito amostras do virus da doença de Aujeszky isoladas no estado do Rio Grande do Sul em 2003. Pesquisa Veterinária Brasileira 25(1):21-24. Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Fepagro Saúde Animal, Estrada do Conde 6000, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br Pseudorabies or Aujeszky’s disease (AD), caused by pseudorabies virus (PRV) is a major concern in swine production. In the state of Rio Grande do Sul, Brazil, AD was only detected in 1954, in cattle. In 2003 two outbreaks of encephalitis occurred on the northern region of the state, close to the border with the state of Santa Catarina. Pseudorabies virus (PRV) was isolated from distinct farms within the region and subjected to antigenic and genomic analyses. These isolates were compared with prototype strains NIA-3 and NP. Antigenic characterization with a panel of monoclonal antibodies (Mabs) directed to viral glycoproteins (gB, gC, gD and gE,) was performed by an imunoperoxidase monolayer assay (IPMA) on infected cell monolayers. Genomic characterization was carried out by restriction enzyme analysis (REA) of the whole DNA viral genome with Bam HI. The antigenic profile of the eight isolates from Rio Grande do Sul as well as strains NIA-3 and NP were similar. REA analysis revealed that all isolates from Rio Grande do Sul displayed a genomic type II arrangement, a genotype often found in other outbreaks of AD previously reported in other Brazilian states. The results obtained suggest that the eight isolates examined here were similar.