PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Assis R.A., Lobato F.C.F., Serakides R., Santos R.L., Dias G.R.C., Nascimento R.A.P., Abreu V.L.V, Parreiras P.M. & Uzal F.A. 2005. Immunohistochemical detection of Clostridia species in paraffin-embedded tissues of experimentally inoculated guinea pigs. Pesquisa Veterinária Brasileira 25(1):4-8. Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos 6627, Cx. Postal 567, Belo Horizonte, MG 30123-970, Brazil. E-mail: assisra@rwnet.com.br Blackleg is caused by Clostridium chauvoei, whereas malignant oedema is caused by C. chauvoei, C. septicum, C. sordellii, C. perfringens type A, and/or C. novyi type A. Anti-C. chauvoei, anti-C. septicum, anti-C. sordellii and anti-C. novyi type A polyclonal antibodies were produced in rabbits and purified in a column of DEAE-cellulose. Aliquots of the antisera were conjugated with fluorescein isothiocyanate and the remaining was used for the streptavidin biotin peroxidase technique (SBPT). SBPT was standardized to detect C. chauvoei, C. septicum, C. sordellii and C. novyi type A in formalin-fixed, paraffin-embedded tissues of guinea pigs. SBPT was compared to a fluorescent antibody technique (FAT). Sections and smears of muscle from inoculation area (MIA), heart, liver, spleen and kidney, were obtained for both SBPT and FAT. Cross-reactions between the different Clostridial species were not observed. C. chauvoei and C. septicum were detected in all specimens from the animals inoculated with these microorganisms, while only sections of muscle obtained from all the animals inoculated with C. sordellii and C. novyi type A were positive. The same results observed by the SBPT, were obtained on tissue smears of these microorganisms stained by the FAT. The results indicate that SBPT is suitable for detection of C. chauvoei, C. septicum, C. sordellii and C. novyi type A in formalin-fixed, paraffin-embedded tissues of guinea pigs.

• Blackleg malignant oedema Clostridia guinea pigs fluorescent antibody technique streptavidin biotin peroxidase technique.

Abstract in Portuguese:

Assis R.A., Lobato F.C.F., Serakides R., Santos R.L., Dias G.R.C., Nascimento R.A.P., Abreu V.L.V, Parreiras P.M. & Uzal F.A. 2005. Immunohistochemical detection of Clostridia species in paraffin-embedded tissues of experimentally inoculated guinea pigs. Pesquisa Veterinária Brasileira 25(1):4-8. Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos 6627, Cx. Postal 567, Belo Horizonte, MG 30123-970, Brazil. E-mail: assisra@rwnet.com.br Blackleg is caused by Clostridium chauvoei, whereas malignant oedema is caused by C. chauvoei, C. septicum, C. sordellii, C. perfringens type A, and/or C. novyi type A. Anti-C. chauvoei, anti-C. septicum, anti-C. sordellii and anti-C. novyi type A polyclonal antibodies were produced in rabbits and purified in a column of DEAE-cellulose. Aliquots of the antisera were conjugated with fluorescein isothiocyanate and the remaining was used for the streptavidin biotin peroxidase technique (SBPT). SBPT was standardized to detect C. chauvoei, C. septicum, C. sordellii and C. novyi type A in formalin-fixed, paraffin-embedded tissues of guinea pigs. SBPT was compared to a fluorescent antibody technique (FAT). Sections and smears of muscle from inoculation area (MIA), heart, liver, spleen and kidney, were obtained for both SBPT and FAT. Cross-reactions between the different Clostridial species were not observed. C. chauvoei and C. septicum were detected in all specimens from the animals inoculated with these microorganisms, while only sections of muscle obtained from all the animals inoculated with C. sordellii and C. novyi type A were positive. The same results observed by the SBPT, were obtained on tissue smears of these microorganisms stained by the FAT. The results indicate that SBPT is suitable for detection of C. chauvoei, C. septicum, C. sordellii and C. novyi type A in formalin-fixed, paraffin-embedded tissues of guinea pigs.

Abstract in English:

Seitz A.L., Colodel E.M., Barros S.S. & Driemeier D. 2005. [Experimental poisoning by Sida carpinifolia (Malvaceae) in sheep.] Intoxicação experimental por Sida carpinifolia (Malvaceae) em ovinos. Pesquisa Veterinária Brasileira 25(1):15-20. Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91540-000, Brazil. E-mail: alseitz@terra.com.br. Seven sheep received dry crushed Sida carpinifolia L.f. One of them died at 18 and other at 53 days of the experiment. Four others were euthanatized and necropsied at 30, 45, 75 and 100 days. For one sheep the supply of S. carpinifolia was interrupted on the 80th day of the experiment, and 70 days later the animal was euthanized and necropsied. The minimal amount of the dry plant consumed was 11 g/kg and the maximum was 30 g/kg. The progression of clinical findings was similar in six animals with slight diarrhea at 20 days of experiment. Neurological signs were observed at 25 days and included ataxia with dysmetria, muscle tremors of the head, atypical postural reactions, frequent falls, sluggish of movements, difficulty in grazing and swallowing. These signs were enhanced when the animals were forced to walk. Four of the animals presented progressive emaciation. The sheep whose supply of the plant was interrupted recovered gradually, and 11 days after the animal returned to normal. During necropsy, only enlarged mesenteric lymph nodes were observed. The histological alterations were more significant in the central nervous system, with multiple and severe cytoplasmic distention and vacuolation which affects specially Purkinje cells of the cerebellum, neurons of cerebral cortex, thalamus, midbrain and the ventral horn of spinal cord. Axonal spheroids in the brain, more frequently in the granular layer of cerebellum were also observed. The cytoplasmic vacuolation was also found in pancreatic acinar cells, renal tubules, thyroid follicular epithelium, hepatocytes and macrophages of lymphoid organs. The ultrastructural lesions observed were cytoplasmic vacuolation, some surrounded by membranes in Purkinje cells of cerebellum and thyroid follicular cells. The sheep, which had S. carpinifolia withdrawn from its diet for 70 days, had no significant histological alterations.

• Toxic plants plant poisoning Sida carpinifolia Malvaceae lysosomal storage disease swainsonine electronic microscopy.

Abstract in Portuguese:

Seitz A.L., Colodel E.M., Barros S.S. & Driemeier D. 2005. [Experimental poisoning by Sida carpinifolia (Malvaceae) in sheep.] Intoxicação experimental por Sida carpinifolia (Malvaceae) em ovinos. Pesquisa Veterinária Brasileira 25(1):15-20. Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91540-000, Brazil. E-mail: alseitz@terra.com.br. Seven sheep received dry crushed Sida carpinifolia L.f. One of them died at 18 and other at 53 days of the experiment. Four others were euthanatized and necropsied at 30, 45, 75 and 100 days. For one sheep the supply of S. carpinifolia was interrupted on the 80th day of the experiment, and 70 days later the animal was euthanized and necropsied. The minimal amount of the dry plant consumed was 11 g/kg and the maximum was 30 g/kg. The progression of clinical findings was similar in six animals with slight diarrhea at 20 days of experiment. Neurological signs were observed at 25 days and included ataxia with dysmetria, muscle tremors of the head, atypical postural reactions, frequent falls, sluggish of movements, difficulty in grazing and swallowing. These signs were enhanced when the animals were forced to walk. Four of the animals presented progressive emaciation. The sheep whose supply of the plant was interrupted recovered gradually, and 11 days after the animal returned to normal. During necropsy, only enlarged mesenteric lymph nodes were observed. The histological alterations were more significant in the central nervous system, with multiple and severe cytoplasmic distention and vacuolation which affects specially Purkinje cells of the cerebellum, neurons of cerebral cortex, thalamus, midbrain and the ventral horn of spinal cord. Axonal spheroids in the brain, more frequently in the granular layer of cerebellum were also observed. The cytoplasmic vacuolation was also found in pancreatic acinar cells, renal tubules, thyroid follicular epithelium, hepatocytes and macrophages of lymphoid organs. The ultrastructural lesions observed were cytoplasmic vacuolation, some surrounded by membranes in Purkinje cells of cerebellum and thyroid follicular cells. The sheep, which had S. carpinifolia withdrawn from its diet for 70 days, had no significant histological alterations.

Abstract in English:

França T.N., Peixoto P.V., Brito M.F., Driemeier D., Mores N. & Zanella J. 2005. [Outbreak of Circovirosis (Porcine Postweaning Multisystemic Wasting Syndrome) in the state of Rio de Janeiro, Brazil.] Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 25(1):39-53. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The first outbreak of Postweaning Multisystemic Wasting Syndrome (PMWS) in swine, which occurred in southeastern Brazil, in the state of Rio de Janeiro, is described. The disease, which affects mainly weaned about 4 month-old pigs, caused the death of at least 14 animals. The property, where the outbreak occurred, had inadequate sanitary and management conditions. Clinically the disease was characterized by wasting, poor development, cough, tachypnoea, dispnoea, diarrhoea, ataxia, tremors after stimulation, decubitus and convulsions. The course of the disease was acute or subacute. The most important post-mortem findings were enlarged lymphnodes, non-collapsed lungs, with consolidated areas mainly in the cranial lobes. Histological lesions consisted mainly of lymphohistiocytic infiltration with multinucleate giant cells in lymph nodes, spleen, Peyer’s patches, kidney, lung and liver, depletion or lymphoid hyperplasia, as well as lymphohistiocytic interstitial pneumonia and areas of secondary bronchopneumonia. The diagnosis was established through observations of the symptoms and typical lesions, and was confirmed by immunohistochemical examination and PCR. The objective of this study was to characterize the epidemiological, clinical and pathological aspects of the outbreak of PMWS, because of the severe direct or indirect economical losses caused by the disease to the world pig industry.

• Postweaning multisystemic wasting syndrome porcine circovirus type 2 pathology immunohistochemistry PCR.

Abstract in Portuguese:

França T.N., Peixoto P.V., Brito M.F., Driemeier D., Mores N. & Zanella J. 2005. [Outbreak of Circovirosis (Porcine Postweaning Multisystemic Wasting Syndrome) in the state of Rio de Janeiro, Brazil.] Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 25(1):39-53. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The first outbreak of Postweaning Multisystemic Wasting Syndrome (PMWS) in swine, which occurred in southeastern Brazil, in the state of Rio de Janeiro, is described. The disease, which affects mainly weaned about 4 month-old pigs, caused the death of at least 14 animals. The property, where the outbreak occurred, had inadequate sanitary and management conditions. Clinically the disease was characterized by wasting, poor development, cough, tachypnoea, dispnoea, diarrhoea, ataxia, tremors after stimulation, decubitus and convulsions. The course of the disease was acute or subacute. The most important post-mortem findings were enlarged lymphnodes, non-collapsed lungs, with consolidated areas mainly in the cranial lobes. Histological lesions consisted mainly of lymphohistiocytic infiltration with multinucleate giant cells in lymph nodes, spleen, Peyer’s patches, kidney, lung and liver, depletion or lymphoid hyperplasia, as well as lymphohistiocytic interstitial pneumonia and areas of secondary bronchopneumonia. The diagnosis was established through observations of the symptoms and typical lesions, and was confirmed by immunohistochemical examination and PCR. The objective of this study was to characterize the epidemiological, clinical and pathological aspects of the outbreak of PMWS, because of the severe direct or indirect economical losses caused by the disease to the world pig industry.

Abstract in English:

Spilki F.R., Silva A.D., Batista H.B.C.R., Oliveira A.P., Winkelmann E., Franco A.C., Porciúncula J.A. & Roehe P.M. 2005. Field evaluation of safety during gestation and horizontal spread of a recombinant differential bovine herpesvirus 1 (BoHV-1) vaccine. Pesquisa Veterinária Brasileira 25(1):54-58. Instituto de Pesquisa Veterinária Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br Bovine herpesvirus type 1 (BoHV-1) is recognized as a major cause of respiratory, reproductive disease and abortion in cattle. Vaccination is widely applied to minimize losses induced by BoHV-1 infections; however, vaccination of dams during pregnancy with modified live virus (MLV) vaccines has been occasionally associated to abortions. We have previously reported the development of a BoHV-1 recombinant virus, constructed with basis on a Brazilian BoHV-1 (Franco et al. 2002a) from which the gene coding for glycoprotein E (gE) was deleted (gE-) by genetic manipulation. Such recombinant has been previously evaluated in its potential as a differential vaccine (gE- vaccine) that allows differentiation between vaccinated and infected animals. Here, in the first part of the present study, the safety of the gE- vaccine during pregnancy was evaluated by the intramuscular inoculation of 107.4 tissue culture 50 % infective doses (TCID50) of the virus into 22 pregnant dams (14 BoHV-1 seronegative; 8 seropositive), at different stages of gestation. Other 15 pregnant dams were kept as non-vaccinated controls. No abortions, stillbirths or fetal abnormalities were seen after vaccination. Seroconversion was observed in both groups of previously seronegative vaccinated animals. In the second part of the study, the potential of the gE- vaccine virus to spread among beef cattle under field conditions was examined. Four heifers were inoculated intranasally with a larger amount (107,6 TCID50) of the gE- vaccine (to increase chances of transmission) and mixed with other sixteen animals at the same age and body condition, in the same grazing area, at a population density equal to the average cattle farming density within the region (one cattle head per 10,000 m2), for 180 days. All animals were monitored daily for clinical signs. Serum samples were collected on days 0, 30, 60 and 180 post-vaccination. Seroconversion was observed only in vaccinated heifers. These results indicate that, under the conditions of the present study, the gE- vaccine virus did not cause any noticeable harmful effect on pregnant dams and on its offspring and did not spread horizontally among cattle.

• Bovine herpesvirus 1 BoHV-1 recombinant gE- vaccine.

Abstract in Portuguese:

Spilki F.R., Silva A.D., Batista H.B.C.R., Oliveira A.P., Winkelmann E., Franco A.C., Porciúncula J.A. & Roehe P.M. 2005. Field evaluation of safety during gestation and horizontal spread of a recombinant differential bovine herpesvirus 1 (BoHV-1) vaccine. Pesquisa Veterinária Brasileira 25(1):54-58. Instituto de Pesquisa Veterinária Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br Bovine herpesvirus type 1 (BoHV-1) is recognized as a major cause of respiratory, reproductive disease and abortion in cattle. Vaccination is widely applied to minimize losses induced by BoHV-1 infections; however, vaccination of dams during pregnancy with modified live virus (MLV) vaccines has been occasionally associated to abortions. We have previously reported the development of a BoHV-1 recombinant virus, constructed with basis on a Brazilian BoHV-1 (Franco et al. 2002a) from which the gene coding for glycoprotein E (gE) was deleted (gE-) by genetic manipulation. Such recombinant has been previously evaluated in its potential as a differential vaccine (gE- vaccine) that allows differentiation between vaccinated and infected animals. Here, in the first part of the present study, the safety of the gE- vaccine during pregnancy was evaluated by the intramuscular inoculation of 107.4 tissue culture 50 % infective doses (TCID50) of the virus into 22 pregnant dams (14 BoHV-1 seronegative; 8 seropositive), at different stages of gestation. Other 15 pregnant dams were kept as non-vaccinated controls. No abortions, stillbirths or fetal abnormalities were seen after vaccination. Seroconversion was observed in both groups of previously seronegative vaccinated animals. In the second part of the study, the potential of the gE- vaccine virus to spread among beef cattle under field conditions was examined. Four heifers were inoculated intranasally with a larger amount (107,6 TCID50) of the gE- vaccine (to increase chances of transmission) and mixed with other sixteen animals at the same age and body condition, in the same grazing area, at a population density equal to the average cattle farming density within the region (one cattle head per 10,000 m2), for 180 days. All animals were monitored daily for clinical signs. Serum samples were collected on days 0, 30, 60 and 180 post-vaccination. Seroconversion was observed only in vaccinated heifers. These results indicate that, under the conditions of the present study, the gE- vaccine virus did not cause any noticeable harmful effect on pregnant dams and on its offspring and did not spread horizontally among cattle.

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.

Abstract in English:

Groff F.H.S., Merlo M.A., Stoll P.A., Stepan A.L., Weiblen R. & Flores E.F. 2005. [Epidemiology and control of pseudorabies outbreaks in the state of Rio Grande do Sul, Brazil, 2003.] Epidemiologia e controle dos focos da doença de Aujeszky no Rio Grande do Sul, em 2003. Pesquisa Veterinária Brasileira 25(1):25-30. Depto Medicina Veterinária Preventiva, Universi-dade Federal de Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil. E-mail: flores@ccr.ufsm.br Aujeszky’s disease (AD) or pseudorabies is an important viral disease of swine and has significant economic impact on the pig industry worldwide. The infection produces direct and indirect economic losses, mainly due to restrictions to international trade of swine products. Since the beginning of the 20th century, AD had been notified in several Brazilian regions, yet the state of Rio Grande do Sul (RS) remained as a “provisionally free” area under the International Organization of Epizooties (OIE) guidelines. In 2003, two outbreaks were notified in swine herds located in northern RS, boundary with Santa Catarina, a state where the infection is endemic. Control/eradication measures consisted in tracing back all swine movements, quarantine and eradication of the affected herds by sanitary slaughter under official inspection. In outbreak # 1 (Pinheirinho do Vale, January/2003) six herds were affected, one of which presented animals with clinical signs. Starting from this outbreak, 146 herds and 42.399 pigs were traced back, six herds (7.822 animals) being depopulated – the herd where the index outbreak plus five other herds with positive serology. The outbreak # 2 (Aratiba, September/2003) resulted in a wider spread of the infection, involving another three counties and 77 herds (9 with clinical signs, 68 with positive serology). From the index case, 109.316 pigs in 630 herds were traced back; 28.443 animals from positive herds were slaughtered. Total numbers reached 151.715 traced back animals in 776 herds; 71 herds were found serologically positive. The adopted measures were efficient to eliminate the outbreaks and to stop the disease spread to neighboring areas, reestablishing the sanitary status previous to the outbreaks.

• Aujeszky’s disease pseudorabies ADV PRV epidemiology.

Abstract in Portuguese:

Groff F.H.S., Merlo M.A., Stoll P.A., Stepan A.L., Weiblen R. & Flores E.F. 2005. [Epidemiology and control of pseudorabies outbreaks in the state of Rio Grande do Sul, Brazil, 2003.] Epidemiologia e controle dos focos da doença de Aujeszky no Rio Grande do Sul, em 2003. Pesquisa Veterinária Brasileira 25(1):25-30. Depto Medicina Veterinária Preventiva, Universi-dade Federal de Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil. E-mail: flores@ccr.ufsm.br Aujeszky’s disease (AD) or pseudorabies is an important viral disease of swine and has significant economic impact on the pig industry worldwide. The infection produces direct and indirect economic losses, mainly due to restrictions to international trade of swine products. Since the beginning of the 20th century, AD had been notified in several Brazilian regions, yet the state of Rio Grande do Sul (RS) remained as a “provisionally free” area under the International Organization of Epizooties (OIE) guidelines. In 2003, two outbreaks were notified in swine herds located in northern RS, boundary with Santa Catarina, a state where the infection is endemic. Control/eradication measures consisted in tracing back all swine movements, quarantine and eradication of the affected herds by sanitary slaughter under official inspection. In outbreak # 1 (Pinheirinho do Vale, January/2003) six herds were affected, one of which presented animals with clinical signs. Starting from this outbreak, 146 herds and 42.399 pigs were traced back, six herds (7.822 animals) being depopulated – the herd where the index outbreak plus five other herds with positive serology. The outbreak # 2 (Aratiba, September/2003) resulted in a wider spread of the infection, involving another three counties and 77 herds (9 with clinical signs, 68 with positive serology). From the index case, 109.316 pigs in 630 herds were traced back; 28.443 animals from positive herds were slaughtered. Total numbers reached 151.715 traced back animals in 776 herds; 71 herds were found serologically positive. The adopted measures were efficient to eliminate the outbreaks and to stop the disease spread to neighboring areas, reestablishing the sanitary status previous to the outbreaks.

Abstract in English:

Silva L.A.F., Fioravanti M.C.S., Trindade B.R., Silva O.C., Eurides D., Cunha P.H.J., Silva M.L. & Moura M.I. 2004.[Foot diseases in dairy cows: association with clinical mastitis, metrites and predisposing factors.] Enfermidades digitais em vacas de aptidão leiteira: associação com mastite clínica, metrites e aspectos epidemiológicos. Pesquisa Veterinária Brasileira 24(4):217-222. Escola de Veterinária, Universidade Federal de Goiás, Cx. Postal 131, Goiânia, GO 74001-970, Brazil. E-mail: lafranco@vet.ufg.br With the objective to investigate a possible association between foot diseases, clinical mastitis and/or metritis and predisposing factors for foot diseases, 5300 dairy cows from 80 intensive and semi-intensive farms were used. In 325 (6.13%) cows only foot disease was diagnosed, in 35 (0.66%) foot disease and clinical mastitis, in 52 (0.98%) foot disease and metritis, in 28 (0.53%) foot disease, clinical mastitis and metritis, in 128 (2.42%) only metritis, in 165 (3.11%) only clinical mastitis, and in 89 (1.68%) cows metritis and clinical mastitis. Rapid changes in the diet, high exposure time of hoof horn to slurry and wet conditions, concrete floors, use of footbaths, low frequency of claw trimming, irregular quarantine, and no attention to health aspects during acquisition of the animals were considered as major risk factors for the occurrence of those diseases. The McNemar test for dependent samples showed significant statistical differences between the occurrence of foot disease, clinical mastitis and metritis, in spite of the poor association between those diseases. It was concluded that there was no expressive relationship between foot diseases, clinical mastitis and metritis in lactent cows.

• Foot diseases mastitis metritis epidemiological factors.

Abstract in Portuguese:

Silva L.A.F., Fioravanti M.C.S., Trindade B.R., Silva O.C., Eurides D., Cunha P.H.J., Silva M.L. & Moura M.I. 2004.[Foot diseases in dairy cows: association with clinical mastitis, metrites and predisposing factors.] Enfermidades digitais em vacas de aptidão leiteira: associação com mastite clínica, metrites e aspectos epidemiológicos. Pesquisa Veterinária Brasileira 24(4):217-222. Escola de Veterinária, Universidade Federal de Goiás, Cx. Postal 131, Goiânia, GO 74001-970, Brazil. E-mail: lafranco@vet.ufg.br With the objective to investigate a possible association between foot diseases, clinical mastitis and/or metritis and predisposing factors for foot diseases, 5300 dairy cows from 80 intensive and semi-intensive farms were used. In 325 (6.13%) cows only foot disease was diagnosed, in 35 (0.66%) foot disease and clinical mastitis, in 52 (0.98%) foot disease and metritis, in 28 (0.53%) foot disease, clinical mastitis and metritis, in 128 (2.42%) only metritis, in 165 (3.11%) only clinical mastitis, and in 89 (1.68%) cows metritis and clinical mastitis. Rapid changes in the diet, high exposure time of hoof horn to slurry and wet conditions, concrete floors, use of footbaths, low frequency of claw trimming, irregular quarantine, and no attention to health aspects during acquisition of the animals were considered as major risk factors for the occurrence of those diseases. The McNemar test for dependent samples showed significant statistical differences between the occurrence of foot disease, clinical mastitis and metritis, in spite of the poor association between those diseases. It was concluded that there was no expressive relationship between foot diseases, clinical mastitis and metritis in lactent cows.

Abstract in English:

Rech R.R, Fighera R.A., Oliveira F.N. & Barros C.S.L. 2004. [Granulomatous meningoencephalitis in cattle grazing vetch (Vicia spp).] Meningoencefalite granulomatosa em bovinos em pastoreio de ervilhaca (Vicia spp). Pesquisa Veterinária Brasileira 24(3): 169-172. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Granulomatous meningoencephalitis was observed in 7 out of 8 adult dairy cows affected by vetch-associated systemic granulomatous disease, although there was no neurological signs associated with the condition. The cellular inflammatory infiltrates were located in the leptomeninges and as perivascular cuffings within the brain and consisted of epithelioid macrophages, lymphocytes, plasm cells and eosinophils. These inflammatory changes varied from mild to severe from animal to animal and among different brain regions of the same animal. Perivascular cuffings were usually more marked than the leptomeningeal infiltrates. Affected brain regions, in decreasing order of intensity, included diencephalon through the level of massa intermedia, mesencephalon at the level of rostral colliculi, pons and cerebellar peduncles, medulla at the level of obex, frontal lobe at the level of the genu of the corpus callosum, and cerebellum. The character and the distribution of the inflammatory changes are emphasized regarding the differential diagnosis with other diseases and lesions of the bovine central nervous system in the context of the Brazilian surveillance program for bovine spongiform encephalopath.

• Diseases of cattle diseases of the central nervous system meningoencephalitis plant poisoning Vicia spp pathology.

Abstract in Portuguese:

Rech R.R, Fighera R.A., Oliveira F.N. & Barros C.S.L. 2004. [Granulomatous meningoencephalitis in cattle grazing vetch (Vicia spp).] Meningoencefalite granulomatosa em bovinos em pastoreio de ervilhaca (Vicia spp). Pesquisa Veterinária Brasileira 24(3): 169-172. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Granulomatous meningoencephalitis was observed in 7 out of 8 adult dairy cows affected by vetch-associated systemic granulomatous disease, although there was no neurological signs associated with the condition. The cellular inflammatory infiltrates were located in the leptomeninges and as perivascular cuffings within the brain and consisted of epithelioid macrophages, lymphocytes, plasm cells and eosinophils. These inflammatory changes varied from mild to severe from animal to animal and among different brain regions of the same animal. Perivascular cuffings were usually more marked than the leptomeningeal infiltrates. Affected brain regions, in decreasing order of intensity, included diencephalon through the level of massa intermedia, mesencephalon at the level of rostral colliculi, pons and cerebellar peduncles, medulla at the level of obex, frontal lobe at the level of the genu of the corpus callosum, and cerebellum. The character and the distribution of the inflammatory changes are emphasized regarding the differential diagnosis with other diseases and lesions of the bovine central nervous system in the context of the Brazilian surveillance program for bovine spongiform encephalopath.

Abstract in English:

Garmatz S.L., Irigoyen L.F., Rech R.R., Brown C.C., Zhang J. & Barros C.S.L. 2004. [Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: Experimental transmission to cattle and characterization of the etiological agent.] Febre catarral maligna em bovinos no Rio Grande do Sul: transmissão experimental para bovinos e caracterização do agente etiológico. Pesquisa Veterinária Brasileira 24(2):93-106. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of malignant catarrhal fever (MCF) occurring in cattle on two farms (A and B) in the municipality of Santiago, state of Rio Grande do Sul (RS), Brazil, and the transmission of the disease to susceptible calves as well as the detection of ovine herpesvirus-2 (OvHV-2) in tissues of affected cattle are reported. The two epizootics occurred from November 2001 to February 2002 (Farm A) and in January-February 2003 (Farm B). Numbers of cattle at risk, morbidity and letality rates were respectively 170, 10.59% and 83.33% for Farm A and 500, 2.4% and 100% for Farm B. Contact between affected cattle and sheep was detected in both farms, but lambing ewes were present only in farm A. Duration of clinical courses, gross findings and histopathology were the same for the affected cattle in both farms. Most affected cattle died or were euthanatized in extremis after a clinical course of 2-8 days. Clinical signs included fever (40.5 and 41.5°C), nasal and ocular discharge, corneal opacity, conjunctivitis, drooling, erosions and ulcerations of the mucosae, diarrhea, hematuria, and neurological disturbances. Eleven necropsies (9 on Farm A, 2 on Farm B) were performed. Gross lesions included erosions and ulcers affecting the mucosae of nasal turbinates, oral cavity, gastrointestinal and urogenital tracts; hemorrhage and necrosis of the tip of the buccal papillae, lymph node enlargement, multifocal white foci in renal cortex, and hyperemia of leptomeninges. Microscopically, there were arteritis and fibrinoid degeneration in medium and small arteries and arterioles of multiple organs and tissues, necrosis and inflammation in several mucosal surfaces, keratitis, conjunctivitis, uveitis, intersticial nephritis, and encephalitis. Transmission experiments were attempted in five calves (E1-E5) by inocculating each of them intravenously with 500 ml of whole heparinized blood from a MCF affected cow. The transmission was suscessful in at least three (E1-E3) of the experimental calves which became sick after an incubation period of 15-27 days. Four experimental calves either died or were euthanatized in extremis after a clinical course which varied from 3 days to 8 weeks. The remaining experimental calf (E5) recovered from a mild disease and was euthanatized 14 weeks after inocculation. Necropsies were performed in all five calves. Clinical signs, necropsy and histopathological findings of three calves (E1-E3) were characteristic of MCF. OvHV-2 viral DNA was detected by the polimerase chain reaction (PCR) test in paraffin embedded tissues from seven cattle out of the 11 spontaneous MCF cases and from three experimental calves (E1-E3). PCR tests resulted negative in the remaining four of the 11 spontaneous MCF cases tested and in two (E4,E5) of the five experimental calves. Immunohistochemistry performed in sections of lymphoid tissue from calf E4 failed to detect BVD virus antigen. The experimental transmission of MCF and the characterization of the etiological agent as OvHV-2 were successfully attempted in cattle for the first time in Brazil.

• Infectious diseases malignant catarrhal fever viral diseases diseases of cattle pathology polimerase chain reation.

Abstract in Portuguese:

Garmatz S.L., Irigoyen L.F., Rech R.R., Brown C.C., Zhang J. & Barros C.S.L. 2004. [Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: Experimental transmission to cattle and characterization of the etiological agent.] Febre catarral maligna em bovinos no Rio Grande do Sul: transmissão experimental para bovinos e caracterização do agente etiológico. Pesquisa Veterinária Brasileira 24(2):93-106. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of malignant catarrhal fever (MCF) occurring in cattle on two farms (A and B) in the municipality of Santiago, state of Rio Grande do Sul (RS), Brazil, and the transmission of the disease to susceptible calves as well as the detection of ovine herpesvirus-2 (OvHV-2) in tissues of affected cattle are reported. The two epizootics occurred from November 2001 to February 2002 (Farm A) and in January-February 2003 (Farm B). Numbers of cattle at risk, morbidity and letality rates were respectively 170, 10.59% and 83.33% for Farm A and 500, 2.4% and 100% for Farm B. Contact between affected cattle and sheep was detected in both farms, but lambing ewes were present only in farm A. Duration of clinical courses, gross findings and histopathology were the same for the affected cattle in both farms. Most affected cattle died or were euthanatized in extremis after a clinical course of 2-8 days. Clinical signs included fever (40.5 and 41.5°C), nasal and ocular discharge, corneal opacity, conjunctivitis, drooling, erosions and ulcerations of the mucosae, diarrhea, hematuria, and neurological disturbances. Eleven necropsies (9 on Farm A, 2 on Farm B) were performed. Gross lesions included erosions and ulcers affecting the mucosae of nasal turbinates, oral cavity, gastrointestinal and urogenital tracts; hemorrhage and necrosis of the tip of the buccal papillae, lymph node enlargement, multifocal white foci in renal cortex, and hyperemia of leptomeninges. Microscopically, there were arteritis and fibrinoid degeneration in medium and small arteries and arterioles of multiple organs and tissues, necrosis and inflammation in several mucosal surfaces, keratitis, conjunctivitis, uveitis, intersticial nephritis, and encephalitis. Transmission experiments were attempted in five calves (E1-E5) by inocculating each of them intravenously with 500 ml of whole heparinized blood from a MCF affected cow. The transmission was suscessful in at least three (E1-E3) of the experimental calves which became sick after an incubation period of 15-27 days. Four experimental calves either died or were euthanatized in extremis after a clinical course which varied from 3 days to 8 weeks. The remaining experimental calf (E5) recovered from a mild disease and was euthanatized 14 weeks after inocculation. Necropsies were performed in all five calves. Clinical signs, necropsy and histopathological findings of three calves (E1-E3) were characteristic of MCF. OvHV-2 viral DNA was detected by the polimerase chain reaction (PCR) test in paraffin embedded tissues from seven cattle out of the 11 spontaneous MCF cases and from three experimental calves (E1-E3). PCR tests resulted negative in the remaining four of the 11 spontaneous MCF cases tested and in two (E4,E5) of the five experimental calves. Immunohistochemistry performed in sections of lymphoid tissue from calf E4 failed to detect BVD virus antigen. The experimental transmission of MCF and the characterization of the etiological agent as OvHV-2 were successfully attempted in cattle for the first time in Brazil.

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.