PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Machado T.F.S., Ferrigno C.R.A., Stopiglia A.J. & Pinto A.C.B.C.F. 2007. [Anatomic features of the dorsal venous sinus in skull of brachycephalous dogs.] Revisão anatômica do seio venoso sagital dorsal no crânio de cães braquicéfalos. Pesquisa Veterinária Brasileira 27(5):194-198. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. E-mail: tfsm@usp.br The dorsal venous sinuses of the Dura mater perform the cerebral and spinal cord drainage to keep homeostasis of the Central Nervous System. Injuries in the cerebral venous network may cause severe deficits, including hemiplegia, hemorrhage, coma and death. The main landmark for neurologic surgery is the Dura mater venous sinus. The aim of this study is to analyse the pathway of the Sinus sagittalis dorsalis in the brachycephalous skull, as the brachycephalous dogs have specific characteristics. The skulls were taken from 8 Boxer dogs and venous perfusion with latex and barium sulfate solution was performed. After the perfusion, radiographies and tomographies were obtained to relate the dorsal sagittal sinus and the skull averages. The cephalic index showed mean values of 91.24±8.34cm, and the cranio-facial index was 2.89±0.23cm. The venous sinus mensuration interface to the skull was: Área = 10.18±4.69mm2; D1 = 11.84±2.35mm; D2 = 19.57±2.61mm; D3 = 17.88±2.31mm; D4 = 25.32±5.68mm e D5 = 24.84±4.40mm.

• Brachycephalous dorsal venous sinus brain vasculature

Abstract in Portuguese:

ABSTRACT.- Machado T.F.S., Ferrigno C.R.A., Stopiglia A.J. & Pinto A.C.B.C.F. 2007. [Anatomic features of the dorsal venous sinus in skull of brachycephalous dogs.] Revisão anatômica do seio venoso sagital dorsal no crânio de cães braquicéfalos. Pesquisa Veterinária Brasileira 27(5):194-198. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. E-mail: tfsm@usp.br The dorsal venous sinuses of the Dura mater perform the cerebral and spinal cord drainage to keep homeostasis of the Central Nervous System. Injuries in the cerebral venous network may cause severe deficits, including hemiplegia, hemorrhage, coma and death. The main landmark for neurologic surgery is the Dura mater venous sinus. The aim of this study is to analyse the pathway of the Sinus sagittalis dorsalis in the brachycephalous skull, as the brachycephalous dogs have specific characteristics. The skulls were taken from 8 Boxer dogs and venous perfusion with latex and barium sulfate solution was performed. After the perfusion, radiographies and tomographies were obtained to relate the dorsal sagittal sinus and the skull averages. The cephalic index showed mean values of 91.24±8.34cm, and the cranio-facial index was 2.89±0.23cm. The venous sinus mensuration interface to the skull was: Área = 10.18±4.69mm2; D1 = 11.84±2.35mm; D2 = 19.57±2.61mm; D3 = 17.88±2.31mm; D4 = 25.32±5.68mm e D5 = 24.84±4.40mm.

Abstract in English:

ABSTRACT.- Baldani C.D., Machado R.Z., Raso T.F. & Pinto A.A. 2007. Serodiagnosis of Babesia equi in horses submitted to exercise stress. Pesquisa Veterinária Brasileira27(4):179-183. Departamento de Patologia Veterinária, Universidade Estadual Paulista, Faculdade de Ciências Agrárias e Veterinárias, Via de Acesso Prof. Paulo Donato Castellane s/n, Jaboticabal, SP 14870-000, Brazil. E-mail: zacarias@fcav.unesp.br A complement fixation test (CFT), performed in microtitre plates, based upon the use of crude antigenic preparation of Babesia equi was adapted for the detection of antibodies in serum of infected horses. The indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) were also used for the immunodiagnosis of B. equi. Serum samples from 15 apparently healthy horses, previously conditioned to a high-speed equine treadmill, were taken before and after exercise. All the samples analyzed were positive for B. equi infection. There were no significant differences (P<0.01) between these 3 tests, or the condition of rest or stress. The combined use of CFT and IFAT or ELISA should be recommended in order to enable veterinary services to more efficiently prevent introduction of infected horses into disease-free areas.

• Babesia equi diagnosis complement fixation indirect fluorescent antibody test enzyme-linked immunosorbent assay

Abstract in Portuguese:

ABSTRACT.- Baldani C.D., Machado R.Z., Raso T.F. & Pinto A.A. 2007. Serodiagnosis of Babesia equi in horses submitted to exercise stress. Pesquisa Veterinária Brasileira27(4):179-183. Departamento de Patologia Veterinária, Universidade Estadual Paulista, Faculdade de Ciências Agrárias e Veterinárias, Via de Acesso Prof. Paulo Donato Castellane s/n, Jaboticabal, SP 14870-000, Brazil. E-mail: zacarias@fcav.unesp.br A complement fixation test (CFT), performed in microtitre plates, based upon the use of crude antigenic preparation of Babesia equi was adapted for the detection of antibodies in serum of infected horses. The indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) were also used for the immunodiagnosis of B. equi. Serum samples from 15 apparently healthy horses, previously conditioned to a high-speed equine treadmill, were taken before and after exercise. All the samples analyzed were positive for B. equi infection. There were no significant differences (P<0.01) between these 3 tests, or the condition of rest or stress. The combined use of CFT and IFAT or ELISA should be recommended in order to enable veterinary services to more efficiently prevent introduction of infected horses into disease-free areas.

Abstract in English:

ABSTRACT.- Pimentel L.A., Riet-Correa F., Guedes K.M., Macêdo J.T.S.A., Medeiros R.M.T. & Dantas A.F.M. 2007. [Primary photosensitization in equidae and ruminants in the Brazilian semi-arid caused by Froelichia humboldtiana (Amaranthaceae).] Fotossensibilização primária em eqüídeos e ruminantes no semi-árido causada por Froelichia humboldtiana (Amaranthaceae). Pesquisa Veterinária Brasileira 27(1):23-28. Hospital Veterinário, CSTR, Universidade Federal de Campina Grande, Campus de Patos, Patos, PB 58708-110, Brazil. E-mail: franklin.riet@pesquisador.com.br Photosensitization is common in the Brazilian semiarid, affecting mainly horses, but also donkeys, mules, sheep and cattle. The dermatitis affects mainly non pigmented skin, and the animals recover after being withdrawn from the pastures. To demonstrate the etiology of the disease, Froelichia humboldtiana (Roem. et Schult.) Seub., collected in the field one or two times a week and kept in the refrigerator for 1-4 days, was administered for 30 or more days as the only food ad libitum to 2 donkeys and one white sheep, and as the only forage ad libitum, to one white horse. No clinical signs were observed in those animals, and serum activities of aspartate-aminotransferase (AST), alanine-aminotransferase (AST), and gamma-glutamyltransferase (GGT) were within normal ranges. In another experiment, one sheep was tied by a rope, during the day, in a pasture of exclusively F. humboldtiana for a 26 days period. Skin lesions characteristic of photosensitization appeared 4-5 days after the start of the experiment and became severe until day 26. After the withdrawal of the animal from the pasture on day 26 it fully recovered within 30 days. In another experiment, 4 sheep were tied by ropes in the same pasture, during the day, for a 29 days period. Another 4 control sheep were maintained in a neighboring pasture without F. humboldtiana. Skin lesions characteristic of photosensitization were observed after 11-25 days of F. humboldtiana grazing. Serum activities of AST and GGT, and serum levels of bilirubin were within normal ranges. At the end of the 29 days grazing F. humboldtiana, 2 sheep were euthanized, and 2 were withdrawn from the pastures. No gross or histologic liver lesions were observed on the 2 sheep euthanized; the other 2 sheep recovered within 17 and 20 days after the end of grazing. One mare and its foal grazed in the same pasture during 44 days. The mare that had a pigmented skin had no dermatitis, but the foal showed dermatitis on the white areas of the skin after 25 days of grazing. The two horses were withdrawn from the pastures after 44 days grazing, and the foal fully recovered within 15 days. These experiments indicate that F. humboldtiana causes primary photosensitization in domestic animals. The absence of lesions in animals ingesting the plant collected in the field and kept refrigerated suggests that F. humboldtiana lost toxicity after collection. The absence of lesions in the eyes of affected animal, which are characteristic of primary photosensitization caused by furocoumarins containing plants, suggests that F. humboldtiana contains a naphthodianthrone derivate, similar to those found in Fagopyrum esculentum and Hypericum perforatum which do not cause eye lesions.

• Primary photosensitization Froelichia humboldtiana Amaranthaceae equidae ruminants dermatitis

Abstract in Portuguese:

ABSTRACT.- Pimentel L.A., Riet-Correa F., Guedes K.M., Macêdo J.T.S.A., Medeiros R.M.T. & Dantas A.F.M. 2007. [Primary photosensitization in equidae and ruminants in the Brazilian semi-arid caused by Froelichia humboldtiana (Amaranthaceae).] Fotossensibilização primária em eqüídeos e ruminantes no semi-árido causada por Froelichia humboldtiana (Amaranthaceae). Pesquisa Veterinária Brasileira 27(1):23-28. Hospital Veterinário, CSTR, Universidade Federal de Campina Grande, Campus de Patos, Patos, PB 58708-110, Brazil. E-mail: franklin.riet@pesquisador.com.br Photosensitization is common in the Brazilian semiarid, affecting mainly horses, but also donkeys, mules, sheep and cattle. The dermatitis affects mainly non pigmented skin, and the animals recover after being withdrawn from the pastures. To demonstrate the etiology of the disease, Froelichia humboldtiana (Roem. et Schult.) Seub., collected in the field one or two times a week and kept in the refrigerator for 1-4 days, was administered for 30 or more days as the only food ad libitum to 2 donkeys and one white sheep, and as the only forage ad libitum, to one white horse. No clinical signs were observed in those animals, and serum activities of aspartate-aminotransferase (AST), alanine-aminotransferase (AST), and gamma-glutamyltransferase (GGT) were within normal ranges. In another experiment, one sheep was tied by a rope, during the day, in a pasture of exclusively F. humboldtiana for a 26 days period. Skin lesions characteristic of photosensitization appeared 4-5 days after the start of the experiment and became severe until day 26. After the withdrawal of the animal from the pasture on day 26 it fully recovered within 30 days. In another experiment, 4 sheep were tied by ropes in the same pasture, during the day, for a 29 days period. Another 4 control sheep were maintained in a neighboring pasture without F. humboldtiana. Skin lesions characteristic of photosensitization were observed after 11-25 days of F. humboldtiana grazing. Serum activities of AST and GGT, and serum levels of bilirubin were within normal ranges. At the end of the 29 days grazing F. humboldtiana, 2 sheep were euthanized, and 2 were withdrawn from the pastures. No gross or histologic liver lesions were observed on the 2 sheep euthanized; the other 2 sheep recovered within 17 and 20 days after the end of grazing. One mare and its foal grazed in the same pasture during 44 days. The mare that had a pigmented skin had no dermatitis, but the foal showed dermatitis on the white areas of the skin after 25 days of grazing. The two horses were withdrawn from the pastures after 44 days grazing, and the foal fully recovered within 15 days. These experiments indicate that F. humboldtiana causes primary photosensitization in domestic animals. The absence of lesions in animals ingesting the plant collected in the field and kept refrigerated suggests that F. humboldtiana lost toxicity after collection. The absence of lesions in the eyes of affected animal, which are characteristic of primary photosensitization caused by furocoumarins containing plants, suggests that F. humboldtiana contains a naphthodianthrone derivate, similar to those found in Fagopyrum esculentum and Hypericum perforatum which do not cause eye lesions.

Abstract in English:

ABSTRACT.- Costa M.M., Machado S.A., Krewer C.C., Ilha M.R.S., Graça D.L., Guaraldi A.L.M. & Vargas A.C. 2006. Pathogenicity of Rhodococcus equi in mice, isolated from environment, human and horse clinical samples. Pesquisa Veterinária Brasileira 26(3):167-170. Laboratório de Bacteriologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Avenida Roraima 1000, Santa Maria, RS 97105-900, Brazil. E-mail: agueda@ccr.ufsm.br Rhodococcus equi is a facultative intracellular pathogen associated with bronchopneumonia, mesenteric lymphadenitis and enterocolitis in foals. Although R. equi is likely to be found in every horse-breeding farm, the clinical disease is unrecognized in most of them. Capsule components, equi factor, micolic acid and some products encoded by the large 85-90Kb plasmid were described as virulence factors. However, the pathogenesis of R. equi infections and the sensibility of foals are not completely understood. The aim of this study was evaluate the virulence of R. equi isolated from human, horses and environment for mices. Nine strains carrying the 85-90Kb plasmid isolated from foal clinical specimens, one from immunodeficient human patient and six plasmidless strains (four isolated from feces, one from pasture and one from immunodeficient human patient) were inoculated in cyclophosphamide immunossuppressed mice. The pathological changes and viability of R. equi cells in the liver of mice was verified after the 3rd, 6th an 10th day after inoculation for horse and environmental isolates and for R. equi isolates from human patients on the 1st, 3rd and 6th day. During the necropsy procedures, infiltrate of macrophages and pyogranulomatous lesions were detected after the sixth pos-inoculation day in the liver and spleen. In horse isolates, only plasmid positive strains were virulent, but in human isolates both strains (plasmid positive e plasmid negative) were virulent. Both groups of the immunossupressed mice inoculated with R. equi isolated from environment showed pathological changes. All R. equi strains were unable to kill non imunossuppressed mice.

• Rhodococcus equi mice virulence cyclophosphamide

Abstract in Portuguese:

ABSTRACT.- Costa M.M., Machado S.A., Krewer C.C., Ilha M.R.S., Graça D.L., Guaraldi A.L.M. & Vargas A.C. 2006. Pathogenicity of Rhodococcus equi in mice, isolated from environment, human and horse clinical samples. Pesquisa Veterinária Brasileira 26(3):167-170. Laboratório de Bacteriologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Avenida Roraima 1000, Santa Maria, RS 97105-900, Brazil. E-mail: agueda@ccr.ufsm.br Rhodococcus equi is a facultative intracellular pathogen associated with bronchopneumonia, mesenteric lymphadenitis and enterocolitis in foals. Although R. equi is likely to be found in every horse-breeding farm, the clinical disease is unrecognized in most of them. Capsule components, equi factor, micolic acid and some products encoded by the large 85-90Kb plasmid were described as virulence factors. However, the pathogenesis of R. equi infections and the sensibility of foals are not completely understood. The aim of this study was evaluate the virulence of R. equi isolated from human, horses and environment for mices. Nine strains carrying the 85-90Kb plasmid isolated from foal clinical specimens, one from immunodeficient human patient and six plasmidless strains (four isolated from feces, one from pasture and one from immunodeficient human patient) were inoculated in cyclophosphamide immunossuppressed mice. The pathological changes and viability of R. equi cells in the liver of mice was verified after the 3rd, 6th an 10th day after inoculation for horse and environmental isolates and for R. equi isolates from human patients on the 1st, 3rd and 6th day. During the necropsy procedures, infiltrate of macrophages and pyogranulomatous lesions were detected after the sixth pos-inoculation day in the liver and spleen. In horse isolates, only plasmid positive strains were virulent, but in human isolates both strains (plasmid positive e plasmid negative) were virulent. Both groups of the immunossupressed mice inoculated with R. equi isolated from environment showed pathological changes. All R. equi strains were unable to kill non imunossuppressed mice.

Abstract in English:

Caron L., Brum M.C.S., Moraes M.P., Golde W.T., Arns C.W. & Grubman M.J. 2005. Granulocyte-macrophage colony-stimulating factor does not increase the potency or efficacy of a foot-and-mouth disease virus subunit vaccine. Pesquisa Veterinária Brasileira 25(3):150-158. USDA, ARS, PIADC-FMD Research Unit, PO.Box 848, Greenport, NY 11944 0848, USA. E-mail: mgrubman@piadc.ars.usda.gov Foot-and-mouth disease (FMD) is one of the most feared diseases of livestock worldwide. Vaccination has been a very effective weapon in controlling the disease, however a number of concerns with the current vaccine including the inability of approved diagnostic tests to reliably distinguish vaccinated from infected animals and the need for high containment facilities for vaccine production, have limited its use during outbreaks in countries previously free of the disease. A number of FMD vaccine candidates have been tested and a replication-defective human adenovirus type 5 (Ad5) vector containing the FMDV capsid (P1-2A) and 3C protease coding regions has been shown to completely protect pigs against challenge with the homologous virus (FMDV A12 and A24). An Ad5-P1-2A+3C vaccine for FMDV O1 Campos (Ad5-O1C), however, only induced a low FMDV-specific neutralizing antibody response in swine potency tests. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been successfully used to stimulate the immune response in vaccine formulations against a number of diseases, including HIV, hepatitis C and B. To attempt to improve the FMDV-specific immune response induced by Ad5-O1C, we inoculated swine with Ad5-O1C and an Ad5 vector containing the gene for porcine GM-CSF (pGM-CSF). However, in the conditions used in this trial, pGM-CSF did not improve the immune response to Ad5-O1C and adversely affected the level of protection of swine challenged with homologous FMDV.

• Foot-and-mouth disease virus O1 Campos Adenovirus Granulocyte-macrophage colony-stimulating factor.

Abstract in Portuguese:

Caron L., Brum M.C.S., Moraes M.P., Golde W.T., Arns C.W. & Grubman M.J. 2005. Granulocyte-macrophage colony-stimulating factor does not increase the potency or efficacy of a foot-and-mouth disease virus subunit vaccine. Pesquisa Veterinária Brasileira 25(3):150-158. USDA, ARS, PIADC-FMD Research Unit, PO.Box 848, Greenport, NY 11944 0848, USA. E-mail: mgrubman@piadc.ars.usda.gov Foot-and-mouth disease (FMD) is one of the most feared diseases of livestock worldwide. Vaccination has been a very effective weapon in controlling the disease, however a number of concerns with the current vaccine including the inability of approved diagnostic tests to reliably distinguish vaccinated from infected animals and the need for high containment facilities for vaccine production, have limited its use during outbreaks in countries previously free of the disease. A number of FMD vaccine candidates have been tested and a replication-defective human adenovirus type 5 (Ad5) vector containing the FMDV capsid (P1-2A) and 3C protease coding regions has been shown to completely protect pigs against challenge with the homologous virus (FMDV A12 and A24). An Ad5-P1-2A+3C vaccine for FMDV O1 Campos (Ad5-O1C), however, only induced a low FMDV-specific neutralizing antibody response in swine potency tests. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been successfully used to stimulate the immune response in vaccine formulations against a number of diseases, including HIV, hepatitis C and B. To attempt to improve the FMDV-specific immune response induced by Ad5-O1C, we inoculated swine with Ad5-O1C and an Ad5 vector containing the gene for porcine GM-CSF (pGM-CSF). However, in the conditions used in this trial, pGM-CSF did not improve the immune response to Ad5-O1C and adversely affected the level of protection of swine challenged with homologous FMDV.

Abstract in English:

Traverso S.D., Correa A.M.R., Schmitz M., Colodel E.M. & Driemeier D. 2004 [Experimental poisoning by Trema micrantha (Ulmaceae) in cattle.] Intoxicação experi-mental por Trema micrantha (Ulmaceae) em bovinos. Pesquisa Veterinária Brasileira 24(4):211-216. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veteriná-ria, UFRGS, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br Leaves of Trema micrantha were orally given to 13 cattle. Ten animals received green leaves in a single dose, two animals received green leaves in fractionated doses, and one received the dried leaves in a single dose. Eight animals showed clinical signs and six of them died. Clinical signs were observed 16 hours after administration and included apathy, anorexia, drooling, progressive weakness, coma and death. Neurological signs as pressing the head against obstacles and head shaking were observed in four animals . Death occurred between 67 and 153 hours after the end of plant ingestion. The main gross lesions were observed in the liver, and included friable consistency, pronounced lobular pattern and areas of haemorrhages. The liver of one bovine was homogeneously dark reddened. Petechial hemorrhages in serosal membranes and edema in the gall bladder were frequently seen. Pale kidneys with red spots in the cortex were observed in one animal. Microscopically, the most striking lesion in the liver was massive coagulative necrosis, associated with centrolobular haemorrhages, observed in four animals. In the liver of one bovine centrolobular necrosis was observed . Tubular renal necrosis was noted in two animals. Additional microscopic lesions were found in the central nervous system of five bovines, especially in the frontal cortex, and included perineuronal and perivascular edema with basophilia and retraction of the neurons. T T. micrantha caused clinical signs with 50g/kg and death with doses of 54g/kg or higher. The fractionated administration of the green leaves as well as the dried leaves did not cause poisoning.

• Poisonous plants plant poisoning Trema micrantha Ulmaceae cattle liver necrosis.

Abstract in Portuguese:

Traverso S.D., Correa A.M.R., Schmitz M., Colodel E.M. & Driemeier D. 2004 [Experimental poisoning by Trema micrantha (Ulmaceae) in cattle.] Intoxicação experi-mental por Trema micrantha (Ulmaceae) em bovinos. Pesquisa Veterinária Brasileira 24(4):211-216. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veteriná-ria, UFRGS, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br Leaves of Trema micrantha were orally given to 13 cattle. Ten animals received green leaves in a single dose, two animals received green leaves in fractionated doses, and one received the dried leaves in a single dose. Eight animals showed clinical signs and six of them died. Clinical signs were observed 16 hours after administration and included apathy, anorexia, drooling, progressive weakness, coma and death. Neurological signs as pressing the head against obstacles and head shaking were observed in four animals . Death occurred between 67 and 153 hours after the end of plant ingestion. The main gross lesions were observed in the liver, and included friable consistency, pronounced lobular pattern and areas of haemorrhages. The liver of one bovine was homogeneously dark reddened. Petechial hemorrhages in serosal membranes and edema in the gall bladder were frequently seen. Pale kidneys with red spots in the cortex were observed in one animal. Microscopically, the most striking lesion in the liver was massive coagulative necrosis, associated with centrolobular haemorrhages, observed in four animals. In the liver of one bovine centrolobular necrosis was observed . Tubular renal necrosis was noted in two animals. Additional microscopic lesions were found in the central nervous system of five bovines, especially in the frontal cortex, and included perineuronal and perivascular edema with basophilia and retraction of the neurons. T T. micrantha caused clinical signs with 50g/kg and death with doses of 54g/kg or higher. The fractionated administration of the green leaves as well as the dried leaves did not cause poisoning.

Abstract in English:

Oliveira C.M.C., Barbosa J.D., Macedo R.S.C., Brito M.F., Peixoto P.V. & Tokarnia C.H. 2004. [A comparative study of the toxicity of Palicourea juruana (Rubiaceae) to buffalo and cattle.] Estudo comparativo da toxidez de Palicourea juruana (Rubiaceae) para búfalos e bovinos. Pesquisa Veterinária Brasileira 24(1):27-30. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: tokarnia@ufrrj.br An experimental study was performed to establish the toxicity of Palicourea juruana for buffaloes and to add new data on the toxicity of this plant for cattle. The clinical and pathological pictures were similar, but a comparison of the lethal doses for buffaloes (1-2g/kg) and cattle (0.25g/kg) shows that the buffalo is at least 4 times more resistant. In experiments performed 10 years earlier with the fresh leaves - collected on the same farm in July, at the beginning of the dry season, only 2 months later than in this second experimental series - the lethal dose for cattle was 2 g/kg. No explanation was found for the extremely high toxicity of the plant observed in the present study.

• Plant poisoning Palicourea juruana Rubiaceae cattle buffaloes.

Abstract in Portuguese:

Oliveira C.M.C., Barbosa J.D., Macedo R.S.C., Brito M.F., Peixoto P.V. & Tokarnia C.H. 2004. [A comparative study of the toxicity of Palicourea juruana (Rubiaceae) to buffalo and cattle.] Estudo comparativo da toxidez de Palicourea juruana (Rubiaceae) para búfalos e bovinos. Pesquisa Veterinária Brasileira 24(1):27-30. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: tokarnia@ufrrj.br An experimental study was performed to establish the toxicity of Palicourea juruana for buffaloes and to add new data on the toxicity of this plant for cattle. The clinical and pathological pictures were similar, but a comparison of the lethal doses for buffaloes (1-2g/kg) and cattle (0.25g/kg) shows that the buffalo is at least 4 times more resistant. In experiments performed 10 years earlier with the fresh leaves - collected on the same farm in July, at the beginning of the dry season, only 2 months later than in this second experimental series - the lethal dose for cattle was 2 g/kg. No explanation was found for the extremely high toxicity of the plant observed in the present study.

Abstract in English:

Canal C.W., Ferreira D.J., Macagnan M., Fallavena L.C.B., Moraes H.L.S. & Wald V.B. 2004. Prevalence of antibodies against chicken anaemia virus (CAV) in broiler breeders in Southern Brazil. Pesquisa Veterinária Brasileira 24(2):89-92. Centro de Diagnóstico e Pesquisa em Patologia Aviária (CDPA), Faculdade de Veterinária da Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91540-000, Brazil. E-mail: claudio.canal@ufrgs.br Chicks infected during the first two weeks of life with chicken anaemia virus (CAV) manifest clinical disease that can be avoided if the breeder hens transfer enough antibodies to their progeny. The objective of the present work was to establish the prevalence and titer of anti-CAV antibodies in some Brazilian broiler hen breeder flocks and verify in which phase of life the birds were infected. A total of 1,709 serum samples from 12 broiler hen flocks vaccinated against CAV and 64 unvaccinated flocks were analyzed for CAV antibodies with an enzyme-linked immunosorbent assay (ELISA). All non-vaccinated breeder flocks were found to be infected with CAV, with 89% of the hens tested presenting antibodies, 52% of these with titers considered high enough to protect their progeny against CAV infection. Likewise, all vaccinated hens had antibody titer to CAV capable of conferring protection to their progeny. Thus, vaccination of hens seems capable of conferring protection to chicks against clinically apparent CAV-associated disease.

• Antibodies avian pathology chicken anemia virus CAV epidemiology prevalence.

Abstract in Portuguese:

Canal C.W., Ferreira D.J., Macagnan M., Fallavena L.C.B., Moraes H.L.S. & Wald V.B. 2004. Prevalence of antibodies against chicken anaemia virus (CAV) in broiler breeders in Southern Brazil. Pesquisa Veterinária Brasileira 24(2):89-92. Centro de Diagnóstico e Pesquisa em Patologia Aviária (CDPA), Faculdade de Veterinária da Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91540-000, Brazil. E-mail: claudio.canal@ufrgs.br Chicks infected during the first two weeks of life with chicken anaemia virus (CAV) manifest clinical disease that can be avoided if the breeder hens transfer enough antibodies to their progeny. The objective of the present work was to establish the prevalence and titer of anti-CAV antibodies in some Brazilian broiler hen breeder flocks and verify in which phase of life the birds were infected. A total of 1,709 serum samples from 12 broiler hen flocks vaccinated against CAV and 64 unvaccinated flocks were analyzed for CAV antibodies with an enzyme-linked immunosorbent assay (ELISA). All non-vaccinated breeder flocks were found to be infected with CAV, with 89% of the hens tested presenting antibodies, 52% of these with titers considered high enough to protect their progeny against CAV infection. Likewise, all vaccinated hens had antibody titer to CAV capable of conferring protection to their progeny. Thus, vaccination of hens seems capable of conferring protection to chicks against clinically apparent CAV-associated disease.

Abstract in English:

Portiansky E.L., Quiroga M.A., Machuca M.A. & Perfumo C.J. 2004. Mycoplasma suis in naturally infected pigs: an ultrastructural and morphometric study. Pesquisa Veterinária Brasileira 24(1):1-5. Instituto de Patología, Faculdad de Ciencias Veterinarias, Universidad Nacional de La Plata, Calle 60 y 118, C.C. 296, (1900) La Plata, Buenos Aires, Argentina. E-mail: elporti@fcv.unlp.edu.ar Swine eperythrozoonosis is a haemotrophic disease caused by Eperythrozoon suis, actually called Mycoplasma suis, an extracellular bacterial organism that apparently adheres to pig erythrocyte membrane, inducing its deformation and damage. Since little is known about the ultrastructural and morphometrical aspects of this microorganism, the present work aimed to deal with these issues. The ultrastructural study revealed the presence of structures corresponding to tubules disseminated throughout the soma of M. suis. A variable separation between the microorganism membrane and that of the erythrocyte was also observed. The structural and positional attitude of M. suis could allow speculation about its mechanism of action.

• Eperythrozoonosis Mycoplasma suis ultrastructure morphometry pathogenesis.

Abstract in Portuguese:

Portiansky E.L., Quiroga M.A., Machuca M.A. & Perfumo C.J. 2004. Mycoplasma suis in naturally infected pigs: an ultrastructural and morphometric study. Pesquisa Veterinária Brasileira 24(1):1-5. Instituto de Patología, Faculdad de Ciencias Veterinarias, Universidad Nacional de La Plata, Calle 60 y 118, C.C. 296, (1900) La Plata, Buenos Aires, Argentina. E-mail: elporti@fcv.unlp.edu.ar Swine eperythrozoonosis is a haemotrophic disease caused by Eperythrozoon suis, actually called Mycoplasma suis, an extracellular bacterial organism that apparently adheres to pig erythrocyte membrane, inducing its deformation and damage. Since little is known about the ultrastructural and morphometrical aspects of this microorganism, the present work aimed to deal with these issues. The ultrastructural study revealed the presence of structures corresponding to tubules disseminated throughout the soma of M. suis. A variable separation between the microorganism membrane and that of the erythrocyte was also observed. The structural and positional attitude of M. suis could allow speculation about its mechanism of action.

Abstract in English:

ABSTRACT.- Traverso S.D., Corrêa A.M.R., Pescador C.A., Colodel E.M., Cruz C.E.F. & Driemeier D. 2002. [Experimental poisoning by Trema micrantha (Ulmaceae) in goats.) Intoxicação experimental por Trema micrantha (Ulmaceae) em caprinos. Pesquisa Veterinária Brasileira 22(4):141-147. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br Green leaves of Trema micrantha were ground and mixed with water in a domestic blender and then administered by stomach tube to seven goats. One additional goat was fed ad libidum with the green leaves of T. micrantha. Clinical signs were observed in six goats that became ill 2 days after having been dosed with or fed the plant. There were five deaths, which occurred until 4 days after ingestion. Affected goats remained static during long periods and kept their heads low. Incoordination, rhythmical movements of the head, apathy, anorexia, and tenesmos were also noticed. Paddling movements and coma were seen in one goat. T. micrantha was toxic at dosages of 30 g/kg or higher. The most significant gross lesions were observed in the livers, which were yellowish, friable, and with pronounced lobular pattern. Their cut surfaces were reddened and depressed areas alternated with whitish ones. The tiver of one goat was slightly but homogeneously reddened but did not show accentuated lobulation. Petechial haemorrhages in the region between the chest and scapula, in the epicardium, mediastinum and serosal membranes of the abdominal organs were also observed. The most importante histologic finding was hepatic centrilobular coagulative necrosis, which was associated with congestion, haemorrhages and degenerative changes in the circumjacent hepatocytes. Additional microscopic lesions were found in the nervous system and included perineuronal and perivascular edema and swollen neurones, especially those of the frontal cortex.

• Poisonous plants plant poisoning Trema micrantha Ulmaceae goats Plantas tóxicas intoxicação por plantas caprinos.

Abstract in Portuguese:

RESUMO.- Traverso S.D., Corrêa A.M.R., Pescador C.A., Colodel E.M., Cruz C.E.F. & Driemeier D. 2002. [Experimental poisoning by Trema micrantha (Ulmaceae) in goats.) Intoxicação experimental por Trema micrantha (Ulmaceae) em caprinos. Pesquisa Veterinária Brasileira 22(4):141-147. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br Sete caprinos receberam, por sonda esofágica, uma suspensão aquosa de folhas verdes de Trema micrantha moídas e um outro recebeu folhas verdes da planta à vontade. Os sinais clínicos iniciaram-se 2 dias após a ingestão e ocorreram em seis caprinos, cinco dos quais morreram em até 4 dias. Os animais doentes permaneciam longos períodos em estação, com cabeça baixa, olhar fixo, apáticos e inapetentes. Tenesmo, incoordenação e movimentos rítmicos laterais da cabeça também foram observados. T. micrantha mostrou-se tóxica a partir de 30g/kg de peso corporal. A alteração macroscópica mais significativa foi observada no fígado, que se apresentou friável, amarelado e com acentuado padrão lobular. Ao corte, havia áreas vermelhas, deprimidas e entremeadas por áreas mais claras. Em um animal, a coloração do fígado era vermelha, homogênea, mais clara que o normal e sem evidenciação do padrão lobular. Petéquias foram constatadas entre a escápula e o esterno, no epicárdio, no mediastino e nas serosas dos órgãos da cavidade abdominal. A principal alteração histológica foi necrose coagulativa centrolobular que, em alguns casos, atingia todo o lóbulo, associada à congestão, hemorragia e alterações degenerativas nos hepatócitos circunjacentes. No sistema nervoso, havia tume fação de neurônios, mais proeminente no córtex frontal, associado a edema perineuronal e perivascular.