PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Teixeira T.F., Holz C.L., Caixeta S.P.M.B., Dezen D., Cibulski S.P., Silva J.R., Rosa J.C.A., Schmidt E., Ferreira J.C., Batista H.B.C.R., Caldas E., Franco A.C. & Roehe P.M. 2008. [Rabies diagnosis in the state of Rio Grande do Sul, Brazil, from 1985 to 2007.] Diagnóstico de raiva no Rio Grande do Sul, Brasil, de 1985 a 2007. Pesquisa Veterinária Brasileira 28(10):515-520. Instituto de Pesquisas Veterinárias Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 2076, Porto Alegre, RS 90001-970, Brazil. E-mail: proehe@ufrgs.br The results of 23 years of rabies diagnosis carried out at the Veterinary Research Institute Desidério Finamor, in the state of Rio Grande do Sul, RS, Brazil, are reported. From 1985 to 2007, a total of 23.460 specimens were examined, corresponding to 95% of the total number of samples submitted to rabies laboratory diagnosis notified within the state. Diagnostic methods included standard techniques such as the fluorescent antibody test (FAT) and mouse inoculation test (MIT). No cases of human rabies occurred in the period. Rabies virus (RV) was detected in 739 specimens (3.1%), from which 656 (88.7%) were from cattle. The virus was also identified in specimens from 23 dogs (3.1%), 21 horses (2.9%), 29 bats (4.0%), 4 cats (0.5%), 3 sheep (0.4%), 2 pigs (0.27%) and a wild animal of undetermined species (0.13%). The last case of rabies associated with a canine variant was diagnosed in 1988. Two cases of rabies associated with bat variant viruses were reported, in a domestic cat (2001) and in a dog (2007). In cattle, a marked tendency to a decrease in the number of cases was detected in the examined period. In contrast, an increase in the number of cases in haematophagous as well as in non haematophagous bats is noticed. However, as the number of bat specimens submitted for diagnosis has increased, this finding most likely reflects a higher degree of awareness on the possible role for bats in the rabies transmission cycle, rather than any particular changes on the virus or its hosts.

• Rabies epidemiology diagnosis incidence

Abstract in Portuguese:

ABSTRACT.- Teixeira T.F., Holz C.L., Caixeta S.P.M.B., Dezen D., Cibulski S.P., Silva J.R., Rosa J.C.A., Schmidt E., Ferreira J.C., Batista H.B.C.R., Caldas E., Franco A.C. & Roehe P.M. 2008. [Rabies diagnosis in the state of Rio Grande do Sul, Brazil, from 1985 to 2007.] Diagnóstico de raiva no Rio Grande do Sul, Brasil, de 1985 a 2007. Pesquisa Veterinária Brasileira 28(10):515-520. Instituto de Pesquisas Veterinárias Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 2076, Porto Alegre, RS 90001-970, Brazil. E-mail: proehe@ufrgs.br The results of 23 years of rabies diagnosis carried out at the Veterinary Research Institute Desidério Finamor, in the state of Rio Grande do Sul, RS, Brazil, are reported. From 1985 to 2007, a total of 23.460 specimens were examined, corresponding to 95% of the total number of samples submitted to rabies laboratory diagnosis notified within the state. Diagnostic methods included standard techniques such as the fluorescent antibody test (FAT) and mouse inoculation test (MIT). No cases of human rabies occurred in the period. Rabies virus (RV) was detected in 739 specimens (3.1%), from which 656 (88.7%) were from cattle. The virus was also identified in specimens from 23 dogs (3.1%), 21 horses (2.9%), 29 bats (4.0%), 4 cats (0.5%), 3 sheep (0.4%), 2 pigs (0.27%) and a wild animal of undetermined species (0.13%). The last case of rabies associated with a canine variant was diagnosed in 1988. Two cases of rabies associated with bat variant viruses were reported, in a domestic cat (2001) and in a dog (2007). In cattle, a marked tendency to a decrease in the number of cases was detected in the examined period. In contrast, an increase in the number of cases in haematophagous as well as in non haematophagous bats is noticed. However, as the number of bat specimens submitted for diagnosis has increased, this finding most likely reflects a higher degree of awareness on the possible role for bats in the rabies transmission cycle, rather than any particular changes on the virus or its hosts.

Abstract in English:

ABSTRACT.- Blagitz M.G., Batista C.F., Souza F.N., Benites N.R., Melville P.A., Stricagnolo C.R., Ricciardi M., Gomes V., Azedo M.R., Sanches B.G.S. & Della Libera A.M.M.P. 2008. [Cellular and microbiological profile of Santa Ines ewes in the lactation and the post-weaning period.] Perfil celular e microbiológico de ovelhas Santa Inês no período lactante e pós-desmame. Pesquisa Veterinária Brasileira 28(9):417-422. Departamento de Clínica Médica, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: magblagitz@usp.br The aim was to evaluate and compare the microbiological and cellular profile of the milk of Santa Ines ewes during the lactation period and the active involution. Milk samples were analyzed from 12 ewes during these distinct periods. Clinical examination of the mammary gland, somatic cell count (SCC), California Mastitis Test (CMT), bacteriologic screening and sensibility of the pathogens in vitro were performed. Most alterations were observed in the active involution period. SCC and CMT were higher in this same period. Besides this, a high persistency of infection occurred. The active involution period did not show high susceptibility. Coagulase-negative staphylococci were the only isolated bacteria. A high antimicrobial sensibility of these pathogens was also encountered.

• Mastitis ewes involution lactation staphylococci

Abstract in Portuguese:

ABSTRACT.- Blagitz M.G., Batista C.F., Souza F.N., Benites N.R., Melville P.A., Stricagnolo C.R., Ricciardi M., Gomes V., Azedo M.R., Sanches B.G.S. & Della Libera A.M.M.P. 2008. [Cellular and microbiological profile of Santa Ines ewes in the lactation and the post-weaning period.] Perfil celular e microbiológico de ovelhas Santa Inês no período lactante e pós-desmame. Pesquisa Veterinária Brasileira 28(9):417-422. Departamento de Clínica Médica, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: magblagitz@usp.br The aim was to evaluate and compare the microbiological and cellular profile of the milk of Santa Ines ewes during the lactation period and the active involution. Milk samples were analyzed from 12 ewes during these distinct periods. Clinical examination of the mammary gland, somatic cell count (SCC), California Mastitis Test (CMT), bacteriologic screening and sensibility of the pathogens in vitro were performed. Most alterations were observed in the active involution period. SCC and CMT were higher in this same period. Besides this, a high persistency of infection occurred. The active involution period did not show high susceptibility. Coagulase-negative staphylococci were the only isolated bacteria. A high antimicrobial sensibility of these pathogens was also encountered.

Abstract in English:

ABSTRACT.- Batista J.S., Bezerra F.S.B., Lira R.A., Carvalho J.R.G., Rosado Neto A.M., Petri A.A. & Teixeira M.M.G. 2008. [Clinical, epidemiological and pathological signs of natural infection in cattle by Trypanosoma vivax in Paraíba, Brazil.] Aspectos clínicos, epidemiológicos e patológicos da infecção natural em bovinos por Trypanosoma vivax na Paraíba. Pesquisa Veterinária Brasileira 28(1):63-69. Departamento de Ciências Animais, Universidade Federal Rural do Semi-árido, BR 110 Km 47, Caixa Postal 147, Mossoró, RN 59625-900, Brazil. E-mail: jaelsbatista@hotmail.com Two outbreaks of trypanosomiasis by Trypanosoma vivax, reported in cattle, occurred on two farms located in the state of Paraíba, northeastern Brazil. The epidemiology, clinical signs and pathology of the disease were studied from May 2005 to November 2006. T. vivax was identified morphologically and by polymerase chain reaction test (PCR). The affected cattle presented anorexia, depression, fever, anemia, weight loss, reduction in milk production, transitory blindness, abortion and some nervous signs as nystagmus, tetany and bruxism. All cattle that presented nervous signs died. Necropsy findings were enlarged lymph and spleen, serous atrophy of the fat depots, proeminence of the splenic white pulp, hydropericardium and pericardial petechiae and ecchymoses on the epicardium. Histologically there was meningoencephalitis. The treatment of the clinical cases with diminazena aceturate was efficient with clearance of the parasite from the blood or disappearance of clinical signs in up to 2 months after the beginning of the outbreak on the two farms studied. The epidemiologic factors favoring the occurrence of the outbreak were the abundance of mechanical vectors, as tabanids and Stomoxys sp., and the introduction into the herd of cattle from farms where the disease occurred. It is suggested that the semiarid of the Brazilian Northeast is an enzootic instability region for trypanosomiasis due to its prolonged periods of drought and high temperatures, constituting during most part of the year an unfavorable environment for the development of vectors.

• Trypanosoma vivax trypanosomiasis cattle outbreak Brazilian Northeast semi-arid

Abstract in Portuguese:

ABSTRACT.- Batista J.S., Bezerra F.S.B., Lira R.A., Carvalho J.R.G., Rosado Neto A.M., Petri A.A. & Teixeira M.M.G. 2008. [Clinical, epidemiological and pathological signs of natural infection in cattle by Trypanosoma vivax in Paraíba, Brazil.] Aspectos clínicos, epidemiológicos e patológicos da infecção natural em bovinos por Trypanosoma vivax na Paraíba. Pesquisa Veterinária Brasileira 28(1):63-69. Departamento de Ciências Animais, Universidade Federal Rural do Semi-árido, BR 110 Km 47, Caixa Postal 147, Mossoró, RN 59625-900, Brazil. E-mail: jaelsbatista@hotmail.com Two outbreaks of trypanosomiasis by Trypanosoma vivax, reported in cattle, occurred on two farms located in the state of Paraíba, northeastern Brazil. The epidemiology, clinical signs and pathology of the disease were studied from May 2005 to November 2006. T. vivax was identified morphologically and by polymerase chain reaction test (PCR). The affected cattle presented anorexia, depression, fever, anemia, weight loss, reduction in milk production, transitory blindness, abortion and some nervous signs as nystagmus, tetany and bruxism. All cattle that presented nervous signs died. Necropsy findings were enlarged lymph and spleen, serous atrophy of the fat depots, proeminence of the splenic white pulp, hydropericardium and pericardial petechiae and ecchymoses on the epicardium. Histologically there was meningoencephalitis. The treatment of the clinical cases with diminazena aceturate was efficient with clearance of the parasite from the blood or disappearance of clinical signs in up to 2 months after the beginning of the outbreak on the two farms studied. The epidemiologic factors favoring the occurrence of the outbreak were the abundance of mechanical vectors, as tabanids and Stomoxys sp., and the introduction into the herd of cattle from farms where the disease occurred. It is suggested that the semiarid of the Brazilian Northeast is an enzootic instability region for trypanosomiasis due to its prolonged periods of drought and high temperatures, constituting during most part of the year an unfavorable environment for the development of vectors.

Abstract in English:

ABSTRACT.- Silva S.M.M.S., Castro R.S., Costa F.A.L., Vasconcelos A.C., Batista M.C.S., Riet-Correa F. & Carvalho E.M.S. 2007. [Epidemiology and symptoms of conidiobolomycosis in sheep in the State of Piauí, Brazil.] Epidemiologia e sinais clínicos da conidiobolomicose em ovinos no Estado do Piauí. Pesquisa Veterinária Brasileira 27(4):184-190. Departamento de Clínica e Cirurgia, Centro de Ciências Agrárias, Universidade Federal do Piauí, Campus da Socopo s/n, Teresina, PI 64049-550, Brazil. E-mail: silvanammss@ufpi.br Conidiobolomycosis is reported in 25 farms, from January 2002 to December 2004, in the state of Piauí. The disease affects only sheep, mainly in April-June. The mean morbidity rate was 2.80%, but was higher in the first semester (2.1%), during the raining period, than in the second one (0.69%), during the dry period. Morbidity rate among flocks varied from 0.1-14.3%. Case fatality rate was 100%, and the clinical manifestation period varied from 1-5 weeks. Clinical signs were serous, mucous and/or bloody nasal secretion, respiratory distress, snoring respiration, cranium-facial asymmetry, exophthalmia, fever and progressive emaciation. Marked depression, sometimes with the head down or head pressing was observed in some cases. Gross, microscopic and ultrastructural lesions and identification of the agent are reported elsewhere. This is the first report of conidiobolomycosis in Brazil, which is endemic and has a high frequency in sheep in the State of Piauí, associated with high rainfalls (1000-1600mm annually) and high temperature (19-36°C).

• Conidiobolomycosis Conidiobolus coronatus zygomycosis clinical signs epidemiology sheep

Abstract in Portuguese:

ABSTRACT.- Silva S.M.M.S., Castro R.S., Costa F.A.L., Vasconcelos A.C., Batista M.C.S., Riet-Correa F. & Carvalho E.M.S. 2007. [Epidemiology and symptoms of conidiobolomycosis in sheep in the State of Piauí, Brazil.] Epidemiologia e sinais clínicos da conidiobolomicose em ovinos no Estado do Piauí. Pesquisa Veterinária Brasileira 27(4):184-190. Departamento de Clínica e Cirurgia, Centro de Ciências Agrárias, Universidade Federal do Piauí, Campus da Socopo s/n, Teresina, PI 64049-550, Brazil. E-mail: silvanammss@ufpi.br Conidiobolomycosis is reported in 25 farms, from January 2002 to December 2004, in the state of Piauí. The disease affects only sheep, mainly in April-June. The mean morbidity rate was 2.80%, but was higher in the first semester (2.1%), during the raining period, than in the second one (0.69%), during the dry period. Morbidity rate among flocks varied from 0.1-14.3%. Case fatality rate was 100%, and the clinical manifestation period varied from 1-5 weeks. Clinical signs were serous, mucous and/or bloody nasal secretion, respiratory distress, snoring respiration, cranium-facial asymmetry, exophthalmia, fever and progressive emaciation. Marked depression, sometimes with the head down or head pressing was observed in some cases. Gross, microscopic and ultrastructural lesions and identification of the agent are reported elsewhere. This is the first report of conidiobolomycosis in Brazil, which is endemic and has a high frequency in sheep in the State of Piauí, associated with high rainfalls (1000-1600mm annually) and high temperature (19-36°C).

Abstract in English:

Batista J.S., Riet-Correa F., Barbosa R.C. & Guerra J.L. 2006. [Experimental infection by Trypanosoma vivax in sheep.] Infecção experimental por Trypanosoma vivax em ovinos. Pesquisa Veterinária Brasileira 26(1):31-37. Hospital Veterinário, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.cnpq.br This paper has the objective to report clinical signs, hematologic changes, and macroscopic and microscopic alterations in sheep infected experimentally with Trypanosoma vivax, isolated from an outbreak in cattle in the semiarid region of the state of Paraíba, northeastern Brazil. Four Santa Inês sheep were inoculated intravenously with 1ml of blood containing 1.85x105 trypomastigotes. Other 4 sheep were used as control. The presence of trypanosomes in the blood and the temperature were recorded daily during the first 30 days and fortnightly from day 31 to day 90 after infection. Also fortnightly, the sheep were weighed and blood samples were obtained for hematological analysis. One inoculated sheep died 75 days after inoculation. The other 3 inoculated and the 4 control sheep were killed 90 days after the beginning of the experiment. T. vivax was observed constantly in the blood of the inoculated sheep from 4-15 days after inoculation. From day 16 to day 30 the parasitemia was lower and irregular. No trypanosomes were observed in the blood after 30 days of infection. A positive linear correlation [Y=0.027x + 38.515, R2=0.944 (P<0.05)] was found between the number of trypanosomes in the blood and body temperature. Significant differences were observed in body weight between inoculated and non-inoculated sheep from day 30 to day 90 after the experiment. From day 30 to day 90 after inoculation trypanosomes were absent or only in low numbers in the blood, and the animals showed anemia and leucopenia. Gross alterations were pale carcasses, enlarged lymph nodes and spleen, and augmented liquid in the peritoneal and pericardiac cavities. Multifocal lymphocytic myocarditis was observed histologically. It is concluded that the isolate is pathogenic to sheep. It is suggested that the semiarid region, where the outbreak occurred, is non-endemic (marginal) for trypanosomosis, and that the disease may occur if the parasite is introduced through vectors.

• Experimental infection Trypanosoma vivax sheep semiarid.

Abstract in Portuguese:

Batista J.S., Riet-Correa F., Barbosa R.C. & Guerra J.L. 2006. [Experimental infection by Trypanosoma vivax in sheep.] Infecção experimental por Trypanosoma vivax em ovinos. Pesquisa Veterinária Brasileira 26(1):31-37. Hospital Veterinário, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.cnpq.br This paper has the objective to report clinical signs, hematologic changes, and macroscopic and microscopic alterations in sheep infected experimentally with Trypanosoma vivax, isolated from an outbreak in cattle in the semiarid region of the state of Paraíba, northeastern Brazil. Four Santa Inês sheep were inoculated intravenously with 1ml of blood containing 1.85x105 trypomastigotes. Other 4 sheep were used as control. The presence of trypanosomes in the blood and the temperature were recorded daily during the first 30 days and fortnightly from day 31 to day 90 after infection. Also fortnightly, the sheep were weighed and blood samples were obtained for hematological analysis. One inoculated sheep died 75 days after inoculation. The other 3 inoculated and the 4 control sheep were killed 90 days after the beginning of the experiment. T. vivax was observed constantly in the blood of the inoculated sheep from 4-15 days after inoculation. From day 16 to day 30 the parasitemia was lower and irregular. No trypanosomes were observed in the blood after 30 days of infection. A positive linear correlation [Y=0.027x + 38.515, R2=0.944 (P<0.05)] was found between the number of trypanosomes in the blood and body temperature. Significant differences were observed in body weight between inoculated and non-inoculated sheep from day 30 to day 90 after the experiment. From day 30 to day 90 after inoculation trypanosomes were absent or only in low numbers in the blood, and the animals showed anemia and leucopenia. Gross alterations were pale carcasses, enlarged lymph nodes and spleen, and augmented liquid in the peritoneal and pericardiac cavities. Multifocal lymphocytic myocarditis was observed histologically. It is concluded that the isolate is pathogenic to sheep. It is suggested that the semiarid region, where the outbreak occurred, is non-endemic (marginal) for trypanosomosis, and that the disease may occur if the parasite is introduced through vectors.

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:

ABSTRACT.- Spilki F.R., Esteves P.A., Franco A.C., Lima M., Holz C.L., Batista H.B.C.R., Driemeier D., Flores E.F., Weiblen R. & Roehe P.M. 2002. [Neurovirulence and neuroinvasiveness of bovine herpesvirus type 1 and 5 in rabbits.] Neurovirulência e neuroinvasividade de Herpesvírus bovinos tipos 1 e 5 em coelhos. Pesquisa Veterinária Brasileira 22(2):58-63. Centro de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde 6000, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@orion.ufrgs.br In order to determine the capacity of bovine herpesvirus type 1 and 5 (BHV-1 and BHV-5) to invade, multiply and spread along the central nervous system (CNS) (neuroinvasiveness), as well as their potential to induce neurological illness (neurovirulence), 30 to 35 days old rabbits were inoculated with the BHV-5 strain EVI 88 / 95 and Los Angeles and Cooper BHV-1 strains, by the intrathecal (IT) and intranasal (IN) routes. The BHV-5 strain induced severe neurological clinical signs in 100% (12/12) of the rabbits inoculated by both routes. Histopathological examination revealed multifocal non-suppurative meningoencephalitis, characterized by multifocal gliosis and perivascular cuffing. Virus was recovered from many parts of the brain. Both BHV-1 strains, when inoculated via 1T route, were not neurovirulent. The strain Los Angeles, after IN inoculation, induced signs of severe respiratory disease (7/7), as well as signs of neurological impairment, indistinguishable from those induced by BHV-5, in 57% (4/7) of the infected rabbits. However, the rabbits with nervous signs revealed at histopathology vasculitis and thrombosis in lungs and brain, the latter with foci of neuronal necrosis, but no lesions indicative of encephalitis, suggesting that neural damage was probably consequent to tissue anoxia. The BHV-1 strain Cooper, after IN inoculation, induced only mild signs of respiratory disease. These findings indicate that the BHV-5 strain was both neuroinvasive and neurovirulent, since it was capable of invading, spreading and multiplying in the rabbits brains by both routes of inoculation, yet causing neurological disease, apparently consequent to vírus induced neural damage. The BHV-1 Los Angeles strain was not neuroinvasive, whereas its neurovirulence was probably consequent to tissue anoxia, which histologically seemed not to be related to direct viral pathogenic effect. The BHV-1 strain Cooper was neither neurovirulent nor neuroinvasive for rabbits. It is possible that these observations bear relationship with the frequent association of BHV-5 with encephalitis in cattle, as opposed to BHV-1 encephalitis, which is a rare event in nature.

• Infectious bovine rhinotracheitis IBR BHV-1 bovine encephalitis herpesvirus BHV-5 Rinotraqueíte infecciosa bovina herpesvírus da encefalite bovina.

Abstract in Portuguese:

RESUMO.- Spilki F.R., Esteves P.A., Franco A.C., Lima M., Holz C.L., Batista H.B.C.R., Driemeier D., Flores E.F., Weiblen R. & Roehe P.M. 2002. [Neurovirulence and neuroinvasiveness of bovine herpesvirus type 1 and 5 in rabbits.] Neurovirulência e neuroinvasividade de Herpesvírus bovinos tipos 1 e 5 em coelhos. Pesquisa Veterinária Brasileira 22(2):58-63. Centro de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde 6000, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@orion.ufrgs.br Com o objetivo de avaliar a capacidade dos herpesvírus bovinos tipos 1 e 5 (BHV-1 e BHV-5) de invadir e replicar no sistema nervoso central (SNC) (neuroinvasividade), bem como sua capacidade de induzir doença neurológica (neurovirulência), coelhos com 30 a 35 dias de idade foram inoculados com uma amostra do Herpesvírus da Encefalite Bovina (BHV-5; amostra EVI 88/95) ou com amostras de BHV-1 (Los Angeles ou Cooper), pelas vias intratecal (IT) e intranasal (IN). A inoculação da amostra de BHV-5, tanto pela via 1T como IN, induziu sinais clínicos neurológicos em 100% (12/12) dos coelhos inoculados. Os exames histopatológicos revelaram um quadro de meningoencefalite não-purulenta multifocal, caracterizada por gliose multifocal e infiltrados perivasculares. O vírus foi isolado de várias áreas do SNC desses animais. As amostras de BHV-1, quando inoculadas pela via IT, não foram neurovirulentas. A amostra Los Angeles de BHV-1, quando administrada pela via IN, induziu sinais respiratórios severos, além de sinais neurológicos em 57% (4/7) dos animais inoculados. Entretanto, o exame histopatológico destes quatro animais revelou vasculite e trombose no pulmão e cérebro, este último apresentando focos de necrose neuronal, porém sem lesões indicativas de encefalite. Isso sugere que os sinais neurológicos foram, provavelmente, consequentes a prejuízos no fluxo sangüíneo encefálico, e não a danos neuronais provocados pela inoculação desse vírus. A amostra Cooper de BHV-1, quando inoculada pela via IN, induziu apenas sinais leves de infecção respiratória. Estes resultados indicam que apenas a amostra de BHV-5 foi capaz de invadir e replicar no encéfalo dos coelhos quando inoculada tanto por via IN como IT, apresentando neuroinvasividade e neurovirulência. É possível que estas observações tenham relação com o fato de amostras de BHV-5 freqüentemente causarem encefalites, em contraposição a infecções pelo BHV-1, onde encefalites são raramente observadas.