PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Penatti M.P.A., Silva A.S., Valadares G.F. & Leite D.S. 2005. Occurrence of F42 colonization factor in Escherichia coli strains isolated from piglets with diarrhea. Pesquisa Veterinária Brasileira 25(1):31-33. Depto Microbiologia e Imunologia, Instituto de Biologia, Unicamp, Campinas, SP 13081-970, Brazil. E-mail: domingos@unicamp.br The objective of this study was to determine the presence of the colonization factor F42 in 168 strains of Escherichia coli isolated from diarrheic stools of newborn piglets. The presence of F42 in 12 (7.1%) strains was detected with the agglutination test. Through the Polymerase Chain Reaction (PCR) of F42 positive strains, gene encoding enterotoxins (ST-I, ST-II, LT-I and LT-II) were detected. The finding of ST-I/ST-II genes in 50% of the strains, ST-I (16%) and ST-II (25%) indicates a strong association of FC F42 with heat-stable enterotoxins (91%). In contrast, the thermolabile enterotoxin (LT-I and LT-II) genes were not detected. Serogroups of F42 positive strains were determined, serogroup O8 being the most prevalent (41,7%). Other serogroups, as there are O9, O11, O18, O32, O35, O98 and O101, were also identified. Thus, FC F42 was confirmed as an additional factor of virulence in the pathogenesis of porcine colibacillosis.

• Escherichia coli F42 piglets fimbriae diarrhea PCR.

Abstract in Portuguese:

Penatti M.P.A., Silva A.S., Valadares G.F. & Leite D.S. 2005. Occurrence of F42 colonization factor in Escherichia coli strains isolated from piglets with diarrhea. Pesquisa Veterinária Brasileira 25(1):31-33. Depto Microbiologia e Imunologia, Instituto de Biologia, Unicamp, Campinas, SP 13081-970, Brazil. E-mail: domingos@unicamp.br The objective of this study was to determine the presence of the colonization factor F42 in 168 strains of Escherichia coli isolated from diarrheic stools of newborn piglets. The presence of F42 in 12 (7.1%) strains was detected with the agglutination test. Through the Polymerase Chain Reaction (PCR) of F42 positive strains, gene encoding enterotoxins (ST-I, ST-II, LT-I and LT-II) were detected. The finding of ST-I/ST-II genes in 50% of the strains, ST-I (16%) and ST-II (25%) indicates a strong association of FC F42 with heat-stable enterotoxins (91%). In contrast, the thermolabile enterotoxin (LT-I and LT-II) genes were not detected. Serogroups of F42 positive strains were determined, serogroup O8 being the most prevalent (41,7%). Other serogroups, as there are O9, O11, O18, O32, O35, O98 and O101, were also identified. Thus, FC F42 was confirmed as an additional factor of virulence in the pathogenesis of porcine colibacillosis.

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:

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:

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.- Fighera R.A., Rozza D.B., Piazer J.V., Copetti M.V., lrigoyen L.F. & Barros C.S.L. 2003. [Interstitial pneumonia in cattle fed moldy sweet potatoes (Ipomoea batatas).] Pneumonia intersticial em bovinos associada à ingestão de batata-doce (lpomoea batatas) mofada. Pesquisa Veterinária Brasileira 23(4):161-166. Depto Patologia, Universidade Federal de Santa Maria, 97105- 900 Santa Maria, RS, Brasil. E-mail: claudioslbarros@uol.com.br Cases of respiratory disease were diagnosed in five out of 23 cattle (21. 7%) after they wete fed moldy damaged sweet potatoes (lpomoea batatas) on a small farm in the county of São Vicente do Sul, state of Rio Grande do Sul, Brazil. Of those five cattle, three died spontaneously and another one was euthanatized for necropsy while showing advanced respiratory clinicai signs. The disease manifested itself approximately 24 hours after the ingestion of the sweet potatoes and lasted from 1 to 4 days. Clinicai signs included dyspnea (labored breathing and abdominal respiration), tachypnea, extended neck with Iow carriage of the head and rhythmical flaring of the nostrils. Two cows were necropsied. Necropsy findings included distended pale and rubbery lungs which failed to collapse when the thorax was open, and marked pulmonar interstitial emphysema and edema. Lymphoid hyperplasia was observed in the hilar nodes and spleen. Histologically, the lesions were those of interstitial pneumonia. Alveolar septa were thickened by fibroblasts and inflammatory cells, and there was hypertrophy and hyperplasia of type li pneumocytes; the interlobular septa were distended by edema and emphysema. The culture of the moldy sweet potatoes yielded Fusarium solani and Fusarium oxysporum.

• Toxic diseases mycotoxicoses respiratory diseases interstitial pneumonia diseases of cattle sweet potatoes lpomoea batatas Intoxicações micotoxicoses doenças respiratórias pneumonia intersticial doenças de bovinos batata-doce.

Abstract in Portuguese:

RESUMO.- Fighera R.A., Rozza D.B., Piazer J.V., Copetti M.V., lrigoyen L.F. & Barros C.S.L. 2003. [Interstitial pneumonia in cattle fed moldy sweet potatoes (Ipomoea batatas).] Pneumonia intersticial em bovinos associada à ingestão de batata-doce (lpomoea batatas) mofada. Pesquisa Veterinária Brasileira 23(4):161-166. Depto Patologia, Universidade Federal de Santa Maria, 97105- 900 Santa Maria, RS, Brasil. E-mail: claudioslbarros@uol.com.br Uma doença respiratória foi diagnosticada em cinco dentre 23 bovinos (21, 7%) após terem sido alimentados com batata-doce (lpomoea batatas) mofada em uma pequena propriedade rural em São Vicente do Sul, Rio Grande do Sul, Brasil. Três dos cinco bovinos afetados morreram espontaneamente, e o quarto foi sacrificado para necropsia quando mostrava sinais clínicos respiratórios avançados. A manifestação clínica iniciara cerca de 24 horas após a ingestão das batatasdoces e a evolução clínica foi de 1 a 4 dias. Os sinais clínicos incluíam dispnéia (respiração laboriosa e abdominal), taquipnéia, pescoço estendido com cabeça baixa e dilatação ritmada das narinas. Dois bovinos foram necropsiados. Os achados de necropsia incluíam pulmões distendidos, pálidos e de consistência borrachenta, que não colapsavam quando o tórax era aberto; enfisema e edema acentuados eram evidentes no pulmão. Os linfonodos e o baço apresentavam alterações características de hiperplasia linfóide. Histologicamente, as lesões eram típicas de pneumonia intersticial. Os septos alveolares estavam espessados por fibroblastos e células inflamatórias, havia hipertrofia e hiperplasia de pneumócitos tipo II; os septos interlobulares estavam distendidos por edema e enfisema. A cultura de amostras das batatas-doces mofadas produziu Fusarium solani e F. oxysporum.

Abstract in English:

ABSTRACT.- Loretti A. P., Ilha M. R. S., Riet-Correa G., Driemeier D., Colodel E. M. & Barros C. S. L. 2002. [Pituitary abscess syndrome in calves following injury of the nasal septum by a plastic device used to prevent suckling.] Síndrome do abscesso pituitário em bezerros associada ao uso de tabuleta nasal para desmame interrompido. Pesquisa Veterinária Brasileira 23(1):39-46. Depto Patologia, Universidade Federal de Santa Maria, Santa Maria, RS 97105- 900, Brazil. E-mail: claudioslbarros@uol.corn.br Outbreaks and sporadic cases of the pituitary abscess syndrome are described in calves in the state of Rio Grande do Sul, southern Brazil. The disease occurred in eight beef cattle farms in the rnunicipalities of Cachoeira do Sul, Lavras do Sul, Bagé, Osório and Vila Nova do Sul, from 1998 to 2002. Thirty-five (1.4%) out of 2,438 calves with 3-12 rnonths of age were affected and 24 (0.98%) died. A nasal plastic device to prevent suckling had been used in all the affected calves. Clinicai signs consisted of nasal discharge, depression, hypertherrnia, ataxia, circling, head tilt and hyperrnetria, exophtalrnos, dysphagia, partial mandibular paralysis, prolapse of the tangue, difficulty in chewing, drooling and in some cases blindness accompanied or not by aqueous flare, prolapse of the ocular globe and corneal opacity. ln the terminal stages of the disease, there was lateral recumbency, opisthotonus and coma. The main necropsy findings included single large hypophyseal or para-hypophyseal abscesses. Those space-occupying lesions dorsally compressed the brain stem and the cranial nerves adjacent to the hypophysis. In sorne cases, there was also osteornyelitis of the basisphenoid bone, single or rnultiple brain abscesses and leptomeningitis affecting the ventral surface of the brain stern and cervical spinal cord. In a few cases, necrotizing or abscedative rhinitis associated with nose device injury was observed. Histologically, those abscesses consisted mainly of neutrophils adrnixed with cellular debris surrounded by numerous mononuclear cells anda fibrous capsule. Fibrino-suppurative rneningitis affecting the leptorneninges of the cerebellum, brain stem and cervical spinal cord was also observed. In some cases, purulent inflammation extended into the hypophyseal parenchyma. Arcanobacterium (Actinomyces) pyogenes was isolated from the abscesses. The diagnosis of pituitary abscess syndrome was based on epidemiological data, clinicai signs, necropsy findings, histological alterations and bacterial cultures.

• Abscess pituitary rete mirabile nose device diseases of cattle pathology central nervous system Abscesso pituitária tabuleta nasal doenças de bovinos patologia sistema nervoso central.

Abstract in Portuguese:

RESUMO.- Loretti A. P., Ilha M. R. S., Riet-Correa G., Driemeier D., Colodel E. M. & Barros C. S. L. 2002. [Pituitary abscess syndrome in calves following injury of the nasal septum by a plastic device used to prevent suckling.] Síndrome do abscesso pituitário em bezerros associada ao uso de tabuleta nasal para desmame interrompido. Pesquisa Veterinária Brasileira 23(1):39-46. Depto Patologia, Universidade Federal de Santa Maria, Santa Maria, RS 97105- 900, Brazil. E-mail: claudioslbarros@uol.corn.br Descrevem-se surtos e casos esporádicos de síndrome do abscesso pituitário em bovinos no Estado do Rio Grande do Sul. A doença ocorreu em 8 propriedades de gado de corte, nos municípios de Cachoeira do Sul, Lavras do Sul, Bagé, Osório e Vila Nova do Sul, no período de 1998 a 2002. De um total de 2.438 bezerros submetidos ao desmame interrompido com o uso da tabuleta nasal, aproximadamente 35 (1,4%) animais adoeceram e 24 (0,98%) morreram. A idade dos bezerros afetados variava entre 3 e 12 meses. Os animais doentes apresentavam corrimento nasal, depressão, febre, incoordenação motora, andar em círculos, desvio lateral da cabeça, hipermetria, exoftalmia, disfagia, mandíbula caída, protusão lingual, dificuldade de mastigação e sialorréia. Em alguns casos, observou-se também cegueira, acompanhada ou não de turvação dos humores do globo ocular, exoftalmia e opacidade da córnea. Nas fases terminais, ocorriam decúbito lateral, convulsões, nistagmo, opistótono, coma e morte. Os principais achados de necropsia consistiam em abscessos únicos pituitários ou parapituitários que comprimiam dorsalniente o tronco encefálico e nervos cranianos próximos à pituitária. Em alguns casos, havia osteomielite envolvendo o osso baso-esfenóide com a formação de abscessos na substância encefálica, leptomeningite na superfície ventral do encéfalo e medula espinhal cervical e rinite necrosante ou abscedativa associada às lesões traumáticas provocadas pela colocação da tabuleta nasal. Histologicamente, os abscessos correspondiam a grandes agregados de neutrófilos e restos celulares circundados por células mononucleares e proliferação de tecido conjuntivo. Meningite fibrinopurulenta nas leptomeninges do cerebelo, tronco encefálico e medula espinhal cervical também foi observada. Em alguns casos, a inflamação purulenta se estendia para o parênquima da pituitária. Arcanobacterium (Actinomyces) pyogenes foi isolado dos abscessos. O diagnóstico de síndrome do abscesso pituitário foi baseado nos dados epidemiológicos, sinais clínicos, achados macroscópicos, histológicos e microbiológicos.

Abstract in English:

ABSTRACT.- Fighera R.A., Souza T.M., Langohr I. & Barros C.S.L. 2002. [Experimental onion Allium cepa (Liliaceae) poisoning in cats.] Intoxicação experimental por cebola, Allium cepa (Liliaceae), em gatos. Pesquisa Veterinária Brasileira 22(2):79-84. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, Rio Grande do Sul, Brazil. Email: anemiaveterinaria@bol.com.br Onion poisoning is reported worlwide in several animal species. The toxic principie (npropyl dissulfide) present in onions causes the transformation of hemoglobin in methemoglobin. In order to study the laboratory, gross and histopathological tindings in onion poisoning in cats, tive 4-month-old cats were fed a single dose of 10g/kg of dried-onion each. Another cat of the sarne age did not receive the onion meal and served as control. AII tive cats developed clinical signs of the toxicosis; one of them died within 24 hours of the ingestion of the onion meal. Clinical signs included apathy, tachycardia, tachypnea, and cyanosis. Laboratory tindings included hemolytic anemia associated with Heinz bodies and methemoglobinemia. Main necropsy tindings were splenomegaly and brown discoloration of blood. Histopathological tindings included splenic and hepatic hemosiderosis and multifocal extramedullary hematopoiesis.

• Poisonous plants Allium cepa onion hemolytic anemia methemoglobinemia Heinz bodies diseases of cats pathology Intoxicação por plantas cebola anemia hemolítica metemoglobinemia corpúsculos de Heinz doenças de gatos patologia.

Abstract in Portuguese:

RESUMO.- Fighera R.A., Souza T.M., Langohr I. & Barros C.S.L. 2002. [Experimental onion Allium cepa (Liliaceae) poisoning in cats.] Intoxicação experimental por cebola, Allium cepa (Liliaceae), em gatos. Pesquisa Veterinária Brasileira 22(2):79-84. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, Rio Grande do Sul, Brazil. Email: anemiaveterinaria@bol.com.br A intoxicação por cebola é relatada em várias espécies animais em muitas partes do mundo. O princípio tóxico (n propil dissulfito) presente na cebola causa a transformação da hemoglobina em metemoglobina. Para estudar os achados laboratoriais, de necropsia e histopatológicos da intoxicação por cebola em gatos, cinco gatos de quatro meses de idade receberam cada um uma dose única de 10g/kg de cebola desidratada por via oral. Um outro gato de mesma idade não recebeu a refeição com cebola e serviu como controle. Todos os cinco gatos desenvolveram sinais clínicos da toxicose; um deles morreu dentro de 24 horas após a ingestão da cebola. Os sinais clínicos incluíram apatia, taquicardia, taquipnéia e cianose. Os achados laboratoriais se caracterizavam por anemia hemolítica associada a corpúsculos de Heinz e metemoglobinemia. Os principais achados de necropsia foram esplenomegalia e sangue de cor marrom. Os achados histopatológicos foram hemossiderose e hematopoese extramedular no baço e fígado.