PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Simionatto S., Vaz E.K., Michelon A., Seixas F.K., Dellagostin O.A. 2005. [Development and evaluation of new strategies for immunization against swine colibacillosis.] Desenvolvimento e avaliação de novas estratégias de imunização contra colibacilose suína. Pes-quisa Veterinária Brasileira 25(2):84-90. Laboratório de Biologia Molecular, Centro de Bio-tecnologia, UFPel, Campus Capão do Leão, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: ssimionatto@bol.com.br Swine colibacillosis caused by enterotoxigenic Escherichia coli remains one of the main sanitary problems in pig farms. The recombinant DNA technology offers the possibility of developing new immunization strategies. This paper describes the development of a subunit vaccine through the expression and purification of the E. coli K88 FaeC fimbrial protein. The gene that codes for this antigen was amplified by PCR and cloned into an E. coli expression vector fused to a 6X histidine tag. The recombinant protein was purified by affinity chromatography and used for mice immunization. In parallel, the same gene was cloned into an eucariotic expression vector with the addition of the Kozak sequence for improving translation of this gene in muscle cells. The resulting plasmid named pUP310 was purified in large scale and used to immunize mice. The immune response afforded by both forms of immunization was monitored by ELISA. There was an immune response in mice inoculated with pUP310 and purified FaeC. It was possible to detect anti-FaeC antibodies 42 days after the first inoculation. The antibody titer increased with time, being still detectable 7 months after the first inoculation. It is concluded that recombinant FaeC and pUP310 are potential tools for immunization of swine against E. coli K88.

• Swine colibacillosis FaeC Escherichia coli DNA vaccine recombinant vaccine.

Abstract in Portuguese:

Simionatto S., Vaz E.K., Michelon A., Seixas F.K., Dellagostin O.A. 2005. [Development and evaluation of new strategies for immunization against swine colibacillosis.] Desenvolvimento e avaliação de novas estratégias de imunização contra colibacilose suína. Pes-quisa Veterinária Brasileira 25(2):84-90. Laboratório de Biologia Molecular, Centro de Bio-tecnologia, UFPel, Campus Capão do Leão, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: ssimionatto@bol.com.br Swine colibacillosis caused by enterotoxigenic Escherichia coli remains one of the main sanitary problems in pig farms. The recombinant DNA technology offers the possibility of developing new immunization strategies. This paper describes the development of a subunit vaccine through the expression and purification of the E. coli K88 FaeC fimbrial protein. The gene that codes for this antigen was amplified by PCR and cloned into an E. coli expression vector fused to a 6X histidine tag. The recombinant protein was purified by affinity chromatography and used for mice immunization. In parallel, the same gene was cloned into an eucariotic expression vector with the addition of the Kozak sequence for improving translation of this gene in muscle cells. The resulting plasmid named pUP310 was purified in large scale and used to immunize mice. The immune response afforded by both forms of immunization was monitored by ELISA. There was an immune response in mice inoculated with pUP310 and purified FaeC. It was possible to detect anti-FaeC antibodies 42 days after the first inoculation. The antibody titer increased with time, being still detectable 7 months after the first inoculation. It is concluded that recombinant FaeC and pUP310 are potential tools for immunization of swine against E. coli K88.

Abstract in English:

Hofer E. & Reis C.M.F. 2005. [Species and serovars of Listeria isolated from sick and clinically healthy animals in Brazil.] Espécies e sorovares de Listeria isolados de animais doentes e portadores no Brasil. Pesquisa Veterinária Brasileira 25(2):79-83. Laboratório de Zoonoses Bacterianas, Depto Bacteriologia, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21045-900, Brazil. E-mail: ehofer@ioc.fiocruz.br Two hundred fourty-six strains of the genus Listeria were isolated from sick and clinically healthy animals, collected in three different regions of Brazil during 1971-2000. About 88.2% (217 cultures) yielded Listeria species from faecal specimens of healthy cattle and 29 strains (11.7%) were isolated from sick animals: 15 (6.0%) from central nervous system (CNS) and 14(5.6%) were from otherwise sterile sites. Phenotyping techniques were used to characterize the Listeria isolates. The commonest were L. innocua 6a and non-typable (140/56.9%), L. monocytogenes 4a (37/15.0%) and 4b (22/8.9%), originated mainly from stools of healthy cattle. From sick animals the predominant species and serovars were L. monocytogenes 4b (14/5.6%), and the higher incidence was observed in ruminants (12/4.8%) and 8/3.2% of the serovar 1a from other animal species (rodents and canines) mainly isolated from CNS samples.

• Listeria species serovars sick and healthy animals.

Abstract in Portuguese:

Hofer E. & Reis C.M.F. 2005. [Species and serovars of Listeria isolated from sick and clinically healthy animals in Brazil.] Espécies e sorovares de Listeria isolados de animais doentes e portadores no Brasil. Pesquisa Veterinária Brasileira 25(2):79-83. Laboratório de Zoonoses Bacterianas, Depto Bacteriologia, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21045-900, Brazil. E-mail: ehofer@ioc.fiocruz.br Two hundred fourty-six strains of the genus Listeria were isolated from sick and clinically healthy animals, collected in three different regions of Brazil during 1971-2000. About 88.2% (217 cultures) yielded Listeria species from faecal specimens of healthy cattle and 29 strains (11.7%) were isolated from sick animals: 15 (6.0%) from central nervous system (CNS) and 14(5.6%) were from otherwise sterile sites. Phenotyping techniques were used to characterize the Listeria isolates. The commonest were L. innocua 6a and non-typable (140/56.9%), L. monocytogenes 4a (37/15.0%) and 4b (22/8.9%), originated mainly from stools of healthy cattle. From sick animals the predominant species and serovars were L. monocytogenes 4b (14/5.6%), and the higher incidence was observed in ruminants (12/4.8%) and 8/3.2% of the serovar 1a from other animal species (rodents and canines) mainly isolated from CNS samples.

Abstract in English:

Dutra I.S., Döbereiner J. & Souza A.M. 2005. [Botulism in beef and dairy cattle fed with poultry litter.] Botulismo em bovinos alimentados com cama de frango. Pesquisa Veterinária Brasileira 25(2):115-119. Depto Apoio, Produção e Saúde Animal, Curso de Medicina Veterinária, Universidade Estadual Paulista (Unesp), Rua Clóvis Pestana 793, Araçatuba, SP 16065-080, Brazil. E-mail: isdutra@fmva.unesp.br Outbreaks of botulism caused by type C and D of the botulinum toxin are frequent in Brazil, and are associated with bone chewing and ingestion of contaminated food and water. This paper reports the epidemiological, clinical, pathological and laboratorial aspects of 7 outbreaks of botulism in beef and dairy cattle fed with poultry litter, which occurred in the states of São Paulo and Minas Gerais, 1989-2000. Five outbreaks occurred in beef cattle herds, raised in confinement or under pasture conditions and supplemented with poultry litter, and 2 outbreaks occurred in dairy farms. From o total of 1,535 cattle supplemented regularily with poultry litter 455 animals (29.64%) died within 2 to 4 weeks. Morbidity and mortality varied from 3.47 to 100% in the 7 outbreaks. In one of the farms the lethality was 60.52%, and in others more than 88.43%, reaching 100% in three farms. Clinical signs were progressive paralysis, difficulties in moving, decubitus, normal alertness, decreased muscular tonus of tongue and tail, sialorrhoe and dyspnoe. At post-mortem examination of 30 cattle no noteable changes were observed. Spores of Clostridium botulinum were found in poultry litter samples collected on 7 farms. In liver, ruminal and intestinal fluid samples from 30 necropsied cattle botulinum toxin of type C (5) and D (9) or of the CD complex (1) were found in at least one of the samples collected from 15 animals, which confirms the clincial, pathological and epidemiological diagnosis of botulism.

• Botulism cattle poultry litter.

Abstract in Portuguese:

Dutra I.S., Döbereiner J. & Souza A.M. 2005. [Botulism in beef and dairy cattle fed with poultry litter.] Botulismo em bovinos alimentados com cama de frango. Pesquisa Veterinária Brasileira 25(2):115-119. Depto Apoio, Produção e Saúde Animal, Curso de Medicina Veterinária, Universidade Estadual Paulista (Unesp), Rua Clóvis Pestana 793, Araçatuba, SP 16065-080, Brazil. E-mail: isdutra@fmva.unesp.br Outbreaks of botulism caused by type C and D of the botulinum toxin are frequent in Brazil, and are associated with bone chewing and ingestion of contaminated food and water. This paper reports the epidemiological, clinical, pathological and laboratorial aspects of 7 outbreaks of botulism in beef and dairy cattle fed with poultry litter, which occurred in the states of São Paulo and Minas Gerais, 1989-2000. Five outbreaks occurred in beef cattle herds, raised in confinement or under pasture conditions and supplemented with poultry litter, and 2 outbreaks occurred in dairy farms. From o total of 1,535 cattle supplemented regularily with poultry litter 455 animals (29.64%) died within 2 to 4 weeks. Morbidity and mortality varied from 3.47 to 100% in the 7 outbreaks. In one of the farms the lethality was 60.52%, and in others more than 88.43%, reaching 100% in three farms. Clinical signs were progressive paralysis, difficulties in moving, decubitus, normal alertness, decreased muscular tonus of tongue and tail, sialorrhoe and dyspnoe. At post-mortem examination of 30 cattle no noteable changes were observed. Spores of Clostridium botulinum were found in poultry litter samples collected on 7 farms. In liver, ruminal and intestinal fluid samples from 30 necropsied cattle botulinum toxin of type C (5) and D (9) or of the CD complex (1) were found in at least one of the samples collected from 15 animals, which confirms the clincial, pathological and epidemiological diagnosis of botulism.

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:

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:

Vargas A.C., Costa M.M., Groff A.C.M., Viana L.R., Krewer C.C., Spricigo D.A. & Kirinus J.K. 2005. [Antimicrobial susceptibility of Campylobacter fetus subsp. venerealis isolated from cattle.] Susceptibilidade antimicrobiana de Campylobacter fetus subsp. venerealis isolado de bovinos. Pesquisa Veterinária Brasileira 25(1):1-3. Laboratório de Bacteriologia do Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: agueda@ccr.ufsm.br Venereal campylobacteriosis is associated with infection of Campylobacter fetus subsp. fetus and Campylobacter fetus subsp. venerealis. The etiological agent is transmitted by natural bull breeding or artificial insemination using contaminated semen. The present study aimed to determine the in vitro susceptibility of C. fetus subsp. venerealis isolates to antimicrobial drugs generally used in clinical and semen treatment. Reference strains of C. fetus subsp. fetus and C. fetus subsp. venerealis and 21 C. fetus isolates were tested. The susceptibility test was performed by using the modified Kirby-Bauer diffusion disc method. C. fetus subsp. fetus reference strain was resistant to lincomycin and penicillin. C. fetus subsp. venerealis was susceptible to all antimicrobial tested, with exception to C.C. KrewerDnalidixic acid. C. fetus subsp. venerealis samples were sensible to amikacin, ampicillin, cefalotin, streptomycin, gentamycin, penicillin and tetracycline. Drug resistance was observed on 42.86% of lincomycin, 4,76 % of enrofloxacin, and 100% to nalidixic acid. In addition 4.76% of the isolates showed intermediate susceptibility to enrofloxacin, neomycin, polimixin B and 9.52% to lincomycin. The susceptibility of C. fetus isolates to antimicrobial drugs commonly used in clinical and semen treatment was demonstrated.

• Campylobacteriosis cattle semen antibiomicrobials.

Abstract in Portuguese:

Vargas A.C., Costa M.M., Groff A.C.M., Viana L.R., Krewer C.C., Spricigo D.A. & Kirinus J.K. 2005. [Antimicrobial susceptibility of Campylobacter fetus subsp. venerealis isolated from cattle.] Susceptibilidade antimicrobiana de Campylobacter fetus subsp. venerealis isolado de bovinos. Pesquisa Veterinária Brasileira 25(1):1-3. Laboratório de Bacteriologia do Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: agueda@ccr.ufsm.br Venereal campylobacteriosis is associated with infection of Campylobacter fetus subsp. fetus and Campylobacter fetus subsp. venerealis. The etiological agent is transmitted by natural bull breeding or artificial insemination using contaminated semen. The present study aimed to determine the in vitro susceptibility of C. fetus subsp. venerealis isolates to antimicrobial drugs generally used in clinical and semen treatment. Reference strains of C. fetus subsp. fetus and C. fetus subsp. venerealis and 21 C. fetus isolates were tested. The susceptibility test was performed by using the modified Kirby-Bauer diffusion disc method. C. fetus subsp. fetus reference strain was resistant to lincomycin and penicillin. C. fetus subsp. venerealis was susceptible to all antimicrobial tested, with exception to C.C. KrewerDnalidixic acid. C. fetus subsp. venerealis samples were sensible to amikacin, ampicillin, cefalotin, streptomycin, gentamycin, penicillin and tetracycline. Drug resistance was observed on 42.86% of lincomycin, 4,76 % of enrofloxacin, and 100% to nalidixic acid. In addition 4.76% of the isolates showed intermediate susceptibility to enrofloxacin, neomycin, polimixin B and 9.52% to lincomycin. The susceptibility of C. fetus isolates to antimicrobial drugs commonly used in clinical and semen treatment was demonstrated.

Abstract in English:

Karam F.S.C., Soares M.P., Haraguchi M., Riet-Correa F., Méndez M.C. & Jarenkow J.A. 2004. [Epidemiological aspects of seneciosis in southern Rio Grande do Sul, Brazil.] Aspectos epidemiológicos da seneciose na região sul do Rio Grande do Sul, Brasil. Pesquisa Veterinária Brasileira 24(4):191-198. Laboratório de Toxicologia, Faculdade de Medicina Veterinária, URCAMP, Bagé, RS 96400-110, Brazil. E-mail: fernando@alternet.com.br Seneciosis is the main cause of livestock mortality due to poisonous plants in the State of Rio Grande do Sul, Brazil. This paper presents epidemiological data of 24 outbreaks in cattle and one in horses, diagnosed by the Regional Diagnostic Laboratory at Pelotas University in southern Rio Grande do Sul, from 1998 to 2000. Additionally, data of 54 outbreaks which occurred in 1978-1997 were analyzed. The farms where outbreaks occurred in 1998-2000 were visited to obtain clinical and epidemiological data and to verify the presence of Senecio spp. Eleven outbreaks (45.83%) affected cattle up to 3 years of age, and 13 (54.16%) cattle over 3 years. Nine (37.5%) outbreaks affected females and 15 (62.5%) males. Ten (41.66%) outbreaks occurred in spring, 4 (16.66%) in summer, 5 (20.83%) in autumn, and 5 (20.83%) in winter. Morbidity rate was estimated with 4.92% and case fatality with 95.59%. The predomionating Senecio species were S. brasiliensis on 12 farms (57.14%), S. selloi on 10 (47.61%), S. oxyphyllus on 6 (28.57%), S. heterotrichius on 3 (14.28%), and S. leptolobus on 1 farm (4.76%). The main clinical signs were progressive emaciation, incoordination, diarrhea, tenesmus, rectal prolapse and aggressiveness. The clinical manifestation periods of affected cattle observed during the farm visits, or of cattle sent for post-mortem examination,were 24-96 hours in 4 outbreaks (16.66%), 4-7 days in 7 (29.16%), 1-2 weeks in 4 (16.66%), 2-3 weeks in 2 (8.33%), 1-2 months in 2 (8.33%), and 2-3 months in 1 outbreak (4.16%). In 4 outbreaks (16.66%) the clinical manifestation period was not established. In outbreaks with longer clinical manifestation periods some animals showed photosensitization. The main necropsy findings were a hard and enlarged liver, distended gall bladder, edema of the mesenterium and abomasum, and increased amount of liquid in the cavities. Histopathological findings were fibroplasia, megalocytosis and biliary ductal proliferation of the liver, and spongy degeneration of the cerebral white matter. Samples of different Senecio species, in different seasons, were analyzed for detection of pyrrolizidine alkaloids (PAs) by thin layer chromatography. Retrorsine was found in Senecio brasiliensis, S. heterotrichius, S. selloi and S. oxyphyllus. In S. brasiliensis and S. heterotrichius one and two more non-identified PAs were detected, respectively. The total PAs concentration by spectrophotometric method was 0.25% for S. brasiliensis, 0.19% for S. heterotrichius, 0.03% for S. oxyphyllus, and 0.03% for S. selloi. The highest PAs concentration occurred in winter (June/July). No alkaloids were found in samples of S. leptolobus. These results show that S. brasiliensis is the most important cause of seneciosis in southern Rio Grande do Sul. Additional data obtained dealt with 54 outbreaks of PAs poisoning in 1978-1997. During this period, 7 outbreaks (12.96%) affected cattle up to 3 years of age, 39 (72.22%) cattle over 3 years, and 3 outbreaks (5.55%) affected cattle of different ages. In 5 outbreaks (9.25%) the age was not informed. Seven outbreaks (12.96%) affected males, 39 (72.22%) females, 3 (5.55%) both sexes, and in 5 outbreaks (9.25%) the sex was not informed. Twenty-three outbreaks (42.59%) occurred in spring, 9 (16.66%) in summer, 9 (16.66%) in autumn, and 13 (24.07%) in winter. The greater number of outbreaks during 1998-2000 (24 outbreaks in 3 years) in regard to 1978-1997 (54 outbreaks in 20 years) is probably due to a decrease of more than 50% in the number of sheep in the region.

• Seneciosis epidemiology poisonous plants Senecio spp Asteraceae pyrrolizidine alkaloids cattle.

Abstract in Portuguese:

Karam F.S.C., Soares M.P., Haraguchi M., Riet-Correa F., Méndez M.C. & Jarenkow J.A. 2004. [Epidemiological aspects of seneciosis in southern Rio Grande do Sul, Brazil.] Aspectos epidemiológicos da seneciose na região sul do Rio Grande do Sul, Brasil. Pesquisa Veterinária Brasileira 24(4):191-198. Laboratório de Toxicologia, Faculdade de Medicina Veterinária, URCAMP, Bagé, RS 96400-110, Brazil. E-mail: fernando@alternet.com.br Seneciosis is the main cause of livestock mortality due to poisonous plants in the State of Rio Grande do Sul, Brazil. This paper presents epidemiological data of 24 outbreaks in cattle and one in horses, diagnosed by the Regional Diagnostic Laboratory at Pelotas University in southern Rio Grande do Sul, from 1998 to 2000. Additionally, data of 54 outbreaks which occurred in 1978-1997 were analyzed. The farms where outbreaks occurred in 1998-2000 were visited to obtain clinical and epidemiological data and to verify the presence of Senecio spp. Eleven outbreaks (45.83%) affected cattle up to 3 years of age, and 13 (54.16%) cattle over 3 years. Nine (37.5%) outbreaks affected females and 15 (62.5%) males. Ten (41.66%) outbreaks occurred in spring, 4 (16.66%) in summer, 5 (20.83%) in autumn, and 5 (20.83%) in winter. Morbidity rate was estimated with 4.92% and case fatality with 95.59%. The predomionating Senecio species were S. brasiliensis on 12 farms (57.14%), S. selloi on 10 (47.61%), S. oxyphyllus on 6 (28.57%), S. heterotrichius on 3 (14.28%), and S. leptolobus on 1 farm (4.76%). The main clinical signs were progressive emaciation, incoordination, diarrhea, tenesmus, rectal prolapse and aggressiveness. The clinical manifestation periods of affected cattle observed during the farm visits, or of cattle sent for post-mortem examination,were 24-96 hours in 4 outbreaks (16.66%), 4-7 days in 7 (29.16%), 1-2 weeks in 4 (16.66%), 2-3 weeks in 2 (8.33%), 1-2 months in 2 (8.33%), and 2-3 months in 1 outbreak (4.16%). In 4 outbreaks (16.66%) the clinical manifestation period was not established. In outbreaks with longer clinical manifestation periods some animals showed photosensitization. The main necropsy findings were a hard and enlarged liver, distended gall bladder, edema of the mesenterium and abomasum, and increased amount of liquid in the cavities. Histopathological findings were fibroplasia, megalocytosis and biliary ductal proliferation of the liver, and spongy degeneration of the cerebral white matter. Samples of different Senecio species, in different seasons, were analyzed for detection of pyrrolizidine alkaloids (PAs) by thin layer chromatography. Retrorsine was found in Senecio brasiliensis, S. heterotrichius, S. selloi and S. oxyphyllus. In S. brasiliensis and S. heterotrichius one and two more non-identified PAs were detected, respectively. The total PAs concentration by spectrophotometric method was 0.25% for S. brasiliensis, 0.19% for S. heterotrichius, 0.03% for S. oxyphyllus, and 0.03% for S. selloi. The highest PAs concentration occurred in winter (June/July). No alkaloids were found in samples of S. leptolobus. These results show that S. brasiliensis is the most important cause of seneciosis in southern Rio Grande do Sul. Additional data obtained dealt with 54 outbreaks of PAs poisoning in 1978-1997. During this period, 7 outbreaks (12.96%) affected cattle up to 3 years of age, 39 (72.22%) cattle over 3 years, and 3 outbreaks (5.55%) affected cattle of different ages. In 5 outbreaks (9.25%) the age was not informed. Seven outbreaks (12.96%) affected males, 39 (72.22%) females, 3 (5.55%) both sexes, and in 5 outbreaks (9.25%) the sex was not informed. Twenty-three outbreaks (42.59%) occurred in spring, 9 (16.66%) in summer, 9 (16.66%) in autumn, and 13 (24.07%) in winter. The greater number of outbreaks during 1998-2000 (24 outbreaks in 3 years) in regard to 1978-1997 (54 outbreaks in 20 years) is probably due to a decrease of more than 50% in the number of sheep in the region.

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.