Resultado da pesquisa (6)

Termo utilizado na pesquisa Richtzenhain L.J.

#1 - A double-antibody sandwich ELISA based on the porcine circovirus type 2 (PCV2) propagated in cell culture for antibody detection, 36(12):1171-1177

Abstract in English:

ABSTRACT.- Cruz T.F., Kanashiro T.M., Castro A.M.M.G., Baldin C.M., Richtzenhain L.J. & Araujo Jr J.P. 2016. A double-antibody sandwich ELISA based on the porcine circovirus type 2 (PCV2) propagated in cell culture for antibody detection. Pesquisa Veterinária Brasileira 36(12):1171-1177. Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita Filho, Botucatu, SP 18618-970, Brazil. E-mail: jpessoa@ibb.unesp.br, tfcruz@yahoo.com.br Few studies have described enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies against porcine circovirus type 2 (PCV2) based on antigens produced in cell culture. Furthermore, few articles have described viral purification techniques for members of the family Circoviridae. This occurs because circoviruses are difficult to isolate, noncytopathogenic, and produce low viral titres in cell culture. Thus, for overcoming these difficulties in the cultivation of PCV2, this study aimed to develop a double-antibody sandwich ELISA based on the cell culture antigen PCV2b for the quantification of anti-PCV2 antibodies. A 20% and 50% discontinuous sucrose cushion was used for viral purification, which enabled the separation of cell culture proteins in the 20% sucrose cushion and a greater viral concentration in the 50% sucrose cushion. Following isopycnic centrifugation, PCV2 was concentrated in the band with density values from 1.330 to 1.395g/cm3. Viral purification was assessed using SDS-PAGE, indirect ELISA and electron microscopy. The standardised ELISA revealed a strong linear correlation (r= 0.826, p<0.001) when compared with a commercial ELISA kit. The assay exhibited low variability (inter-assay coefficient of variation of 4.24% and intra-assay of 1.80%) and excellent analytical specificity conferred by the capture antibody produced in rabbit. Thus, this ELISA is a rapid, specific and convenient method for the detection of antibodies against PCV2 in studies of experimental and natural infection, and in monitoring the response to vaccination on commercial farms.

Abstract in Portuguese:

RESUMO.- Cruz T.F., Kanashiro T.M., Castro A.M.M.G., Baldin C.M., Richtzenhain L.J. & Araujo Jr J.P. 2016. A double-antibody sandwich ELISA based on the porcine circovirus type 2 (PCV2) propagated in cell culture for antibody detection. [Sandwich ELISA com duplo anticorpo baseado no circovirus suíno tipo 2 (PCV2) produzido em cultivo celular para detecção de anticorpos.] Pesquisa Veterinária Brasileira 36(12):1171-1177. Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita Filho, Botucatu, SP 18618-970, Brazil. E-mail: jpessoa@ibb.unesp.br, tfcruz@yahoo.com.br Há poucos relatos na literatura de métodos de ELISA (Enzyme-linked immunosorbent assay), para a detecção de anticorpos contra o circovírus suíno tipo 2 (PCV2), baseados em antígenos produzidos em cultivo celular, bem como uma escassez de trabalhos descrevendo técnicas de purificação viral para os membros da família Circoviridae. Isso ocorre, pois os circovírus são de difícil isolamento, não causam efeito citopático e produzem um baixo título viral em cultivo celular. Assim, para superar essas dificuldades encontradas no cultivo do PCV2, este estudo objetivou desenvolver um sandwich ELISA com duplo anticorpo, baseado no antígeno de PCV2 produzido em cultivo celular, para a quantificação de anticorpos anti-PCV2. Um colchão de sacarose descontínuo a 20% e 50% foi utilizado para a purificação viral, o qual possibilitou a separação das proteínas oriundas do cultivo celular no colchão de sacarose a 20% e uma maior concentração viral no colchão de sacarose a 50%. Com a ultracentrifugação isopícnica, o PCV2 ficou mais concentrado na banda com valores de densidade de 1,330 a 1,395g/cm3. A purificação viral foi avaliada pelas técnicas de SDS-PAGE, ELISA indireto e microscopia eletrônica. Assim, o método de ELISA padronizado revelou uma forte correlação linear (r = 0,826, p <0,001) quando comparado com um kit de ELISA comercial. O ensaio demonstrou baixa variabilidade (coeficientes de variação inter-teste de 4,24% e intra-teste de 1,80%) e uma excelente especificidade analítica conferida pelo anticorpo de captura produzido em coelho. Portanto, o método de ELISA demonstrou ser rápido, específico e conveniente para a detecção de anticorpos contra o PCV2 em estudos de infecção natural e experimental, além da monitoria da resposta à vacinação contra o PCV2 em granjas comerciais.


#2 - Phylogenetic analysis of rabies virus isolated from herbivores in Minas Gerais and São Paulo border (2000-2009), Brazil, 34(12):1196-1202

Abstract in English:

ABSTRACT.- Estévez Garcia A.I., Peixoto H.C., Silva S.O., Polo G., Alves A.J., Brandão P.E., Cunha E.M. & Richtzenhain L.J. 2014. Phylogenetic analysis of rabies virus isolated from herbivores in Minas Gerais and São Paulo border (2000-2009), Brazil. Pesquisa Veterinária Brasileira 34(12):1196-1202. Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de 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: isaestgar@yahoo.com Rabies transmitted by the hematophagous bat Desmodus rotundus represents a public health concern and a burden for the Brazilian livestock industry. Current evidence suggests that rabies occurrence is related to landscape characteristics, topography, hydrography, animal production systems and land use. However, a few studies have analyzed the possible connections among geographic factors and the molecular diversity of the rabies virus, furthering the understanding of the spatial and temporal dynamics of outbreaks. A study reported that the latest rabies epizootics in herbivores reported in the eastern region of São Paulo (close to the Minas Gerais border) occurred in two epidemic waves; the first was before 1998, and the other occurred after 1999. Using this evidence, the aim of the present study was to analyze cases of rabies in herbivores in the southern region of Minas Gerais (2000-2009) and their possible relationship with the aforementioned epidemics, considering the geographic characteristics of the region. Partial sequences of glycoprotein (539 nt) and nucleoprotein genes (414 nt) were obtained from 31 rabies virus isolates from herbivores. A phylogenetic tree was proposed for each genomic region using the Neighbor joining method, fixing the Kimura 2-parameter evolution model with a bootstrap level of 1,000 replications. Genetic sublineages were plotted on maps, considering rabies risk areas for herbivores in São Paulo, as well as topographic characteristics and hydrographic basins, to visualize any apparent distribution pattern influenced by those features. The phylogenetic trees had concordant topologies, suggesting a possible common origin for rabies outbreaks in herbivores along the SP/MG border, surrounding the less elevated portions of the Serra da Mantiqueira and along the hydrographic basins of Piracicaba/Jaguarí, Paranaíba do Sul, Grande, Pardo and Mogi-Guaçu rivers.The co-circulation of several viral lineages was observed in some municipalities, possibly due to an overlapping of rabies outbreaks. Inferred protein sequences of both genes showed synonymous mutations, except among residues 20 to 200, corresponding to the external domain of the glycoprotein. This information prompted cooperation among the animal health services of both states to reinforce rabies control in the border area.

Abstract in Portuguese:

RESUMO.- Estévez Garcia A.I., Peixoto H.C., Silva S.O., Polo G., Alves A.J., Brandão P.E., Cunha E.M. & Richtzenhain L.J. 2014. Phylogenetic analysis of rabies virus isolated from herbivores in Minas Gerais and São Paulo border (2000-2009), Brazil. [Análise filogenética de isolados do vírus da raiva de herbívoros na fronteira de Minas Gerais e São Paulo (2000-2009), Brasil.] Pesquisa Veterinária Brasileira 34(12):1196-1202. Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de 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: isaestgar@yahoo.com A raiva transmitida por morcegos hematófagos da espécie Desmodus rotundus representa uma preocupação de saúde pública e causa de importantes prejuízos para a pecuária brasileira. A evidência atual sugere que a ocorrência de raiva está relacionada às características da paisagem, topografia, hidrografia, sistemas de produção animal e usos da terra. Contudo, existem poucos estudos que analisem as possíveis conexões entre fatores geográficos e a diversidade molecular do vírus da raiva, permitindo a compreensão da dinâmica espacial e temporal dos focos de raiva. Um desses trabalhos estabeleceu que a última epizootia de raiva dos herbívoros registrada no leste do estado de São Paulo (na fronteira com Minas Gerais), aconteceu em duas ondas epidêmicas, sendo a primeira em 1998 e, em 1999, a segunda. Considerando esta evidência, o intuito do presente estudo foi analisar casos de raiva em herbívoros na região sudeste de Minas Gerais (2000-2009) e sua possível relação com a epidemia previamente mencionada, incluindo as características geográficas da região. Foram obtidas sequencias parciais dos genes da glicoproteína (539 nt) e da nucleoproteína (414 nt) a partir de 31 isolados de vírus da raiva procedentes de herbívoros. Foi proposta uma árvore filogenética para cada região genômica usando o método de Neighbor joining, fixando o modelo evolutivo Kimura 2 - parâmetros com um nível de bootstrap de 1000 replicações. As sublinhagens genéticas foram localizadas sobre mapas, considerando as áreas de risco para raiva dos herbívoros em São Paulo, assim como as características topográficas e bacias hidrográficas com o intuito de visualizar qualquer padrão aparente de distribuição segundo essas características. As duas árvores filogenéticas mostraram topologias concordantes, sugerindo uma possível origem comum para os surtos que aconteceram ao longo da fronteira SP/MG, ao redor das porções menos elevadas da Serra da Mantiqueira e acompanhando as bacias hidrográficas dos rios Piracicaba/Jaguarí, Paranaíba do Sul, Grande, Pardo e Mogi-Guaçu. Foi possível observar circulação de varias linhagens virais simultaneamente em alguns municípios, possivelmente por causa de sobreposição de surtos. As sequencias de proteína inferidas a partir dos dois genes mostraram mutações sinônimas, excetuando aquelas encontradas entre os resíduos 20 a 200, correspondentes ao domínio externo da glicoproteína. Esta informação salienta a importância da cooperação entre as autoridades sanitárias de ambos os estados para reforçar o programa de controle da doença nas áreas limítrofes.


#3 - Rapid detection of bovine coronavirus by a semi-nested RT-PCR, 29(11):869-873

Abstract in English:

ABSTRACT.- Asano K.M, Souza S.P., Silva S.O.S., Richtzenhain L.J. & Brandão P.E. 2009. Rapid detection of bovine coronavirus by a semi-nested RT-PCR. Pesquisa Veterinária Brasileira 29(11):869-873. Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: karen.asano@gmail.com Bovine coronavirus (BCoV) is a member of the group 2 of the Coronavirus (Nidovirales: Coronaviridae) and the causative agent of enteritis in both calves and adult bovine, as well as respiratory disease in calves. The present study aimed to develop a semi-nested RT-PCR for the detection of BCoV based on representative up-to-date sequences of the nucleocapsid gene, a conserved region of coronavirus genome. Three primers were designed, the first round with a 463bp and the second (semi-nested) with a 306bp predicted fragment. The analytical sensitivity was determined by 10-fold serial dilutions of the BCoV Kakegawa strain (HA titre: 256) in DEPC treated ultra-pure water, in fetal bovine serum (FBS) and in a BCoV-free fecal suspension, when positive results were found up to the 10-2, 10-3 and 10-7 dilutions, respectively, which suggests that the total amount of RNA in the sample influence the precipitation of pellets by the method of extraction used. When fecal samples was used, a large quantity of total RNA serves as carrier of BCoV RNA, demonstrating a high analytical sensitivity and lack of possible substances inhibiting the PCR. The final semi-nested RT-PCR protocol was applied to 25 fecal samples from adult cows, previously tested by a nested RT-PCR RdRp used as a reference test, resulting in 20 and 17 positives for the first and second tests, respectively, and a substantial agreement was found by kappa statistics (0.694). The high sensitivity and specificity of the new proposed method and the fact that primers were designed based on current BCoV sequences give basis to a more accurate diagnosis of BCoV-caused diseases, as well as to further insights on protocols for the detection of other Coronavirus representatives of both Animal and Public Health importance.

Abstract in Portuguese:

RESUMO.- Asano K.M, Souza S.P., Silva S.O.S., Richtzenhain L.J. & Brandão P.E. 2009. Rapid detection of bovine coronavirus by a semi-nested RT-PCR. [Detecção rápida do Coronavírus Bovino (BCoV) por meio de uma semi-nested RT-PCR.] Pesquisa Veterinária Brasileira 29(11):869-873. Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: karen.asano@gmail.com O Coronavírus bovino (BCoV) pertence ao grupo 2 do gênero Coronavirus (Nidovirales: Coronaviridae) e é agente causador de enterites tanto em bezerros como em bovinos adultos, bem como de doença respiratória em bezerros. O presente estudo teve por objetivo desenvolver uma semi-nested RT-PCR para a detecção do BCoV com base em seqüências representativas e recentes do gene do nucleocapsídeo, região conservada do genoma dos coronavírus. Três primers foram desenhados, a primeira amplificação com um fragmento esperado de 463pb e a segunda (semi-nested) com um fragmento esperado de 306pb. A sensibilidade analítica foi determinada pela diluição do BCoV cepa Kakegawa (título HA: 256) na base de 10 em água ultra-pura tratada com DEPC, em soro fetal bovino (SFB) e em uma suspensão fecal negativa para o BCoV, onde foram encontrados resultados positivos até a diluição de 10-2, 10-3 e 10-7, respectivamente. Este resultado sugere que a quantidade total de RNA na amostra influencia na precipitação dos pellets pelo método de extração utilizado. Quando se utiliza amostra fecal, a grande quantidade de RNA total funciona como carreadora do RNA do BCoV, demonstrando elevada sensibilidade analítica e ausência de possíveis substâncias inibidoras da PCR. O protocolo final da semi-nested RT-PCR foi aplicado a 25 amostras fecais de vacas adultas, previamente avaliadas por uma nested RT-PCR RdRp utilizada como teste de referência, resultando em 20 e 17 amostras positivas para o primeiro e segundo teste, respectivamente. Os resultados dos dois sistema de diagnóstico apresentaram concordância substancial (kappa: 0,694). A elevada sensibilidade e especificidade do novo método proposto e o fato de que os primers foram desenhados baseados em sequências atuais do BCoV, oferecem bases para o diagnóstico mais acurado de infecções causadas pelo BCoV, assim como para novas perspectivas em protocolos de detecção de outros Coronavírus de importância tanto em saninade animal quanto em saúde pública.


#4 - Genetic grouping of avian infectious bronchitis virus isolated in Brazil, based on RT-PCR/RFLP analysis of the S1 gene, p.190-194

Abstract in English:

ABSTRACT.- Montassier M.F.S., Brentano L., Montassier H.J. & Richtzenhain L.J. 2008. Genetic grouping of avian infectious bronchitis virus isolated in Brazil, based on RT-PCR/RFLP analysis of the S1 gene. Pesquisa Veterinária Brasileira 28(3):190-194. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando de Paiva 87, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Twelve Brazilian isolates and one reference vaccine strain of avian infectious bronchitis virus (IBV) were propagated in embryonating chicken eggs. The entire S1 glycoprotein gene of these viruses was analysed by reverse-transcriptase-polymerase chain reaction and restriction fragment length polymorphism (RT-PCR-RFLP), using the restriction enzymes HaeIII, XcmI and BstyI. The RFLP patterns led to the classification of these isolates into five distinct genotypes: A, B, C, D and Massachusetts. Five of twelve isolates were grouped in Massachusetts genotype and the remaining seven viruses were classified into four distinct genotypes: A (2), B (2), C (2) or D (1). Such genotyping classification agreed with previous immunological analysis for most of these viruses, highlighting the occurrence of a relevant variability among the IBV strains that are circulating in Brazilian commercial poultry flocks.

Abstract in Portuguese:

ABSTRACT.- Montassier M.F.S., Brentano L., Montassier H.J. & Richtzenhain L.J. 2008. Genetic grouping of avian infectious bronchitis virus isolated in Brazil, based on RT-PCR/RFLP analysis of the S1 gene. Pesquisa Veterinária Brasileira 28(3):190-194. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando de Paiva 87, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Twelve Brazilian isolates and one reference vaccine strain of avian infectious bronchitis virus (IBV) were propagated in embryonating chicken eggs. The entire S1 glycoprotein gene of these viruses was analysed by reverse-transcriptase-polymerase chain reaction and restriction fragment length polymorphism (RT-PCR-RFLP), using the restriction enzymes HaeIII, XcmI and BstyI. The RFLP patterns led to the classification of these isolates into five distinct genotypes: A, B, C, D and Massachusetts. Five of twelve isolates were grouped in Massachusetts genotype and the remaining seven viruses were classified into four distinct genotypes: A (2), B (2), C (2) or D (1). Such genotyping classification agreed with previous immunological analysis for most of these viruses, highlighting the occurrence of a relevant variability among the IBV strains that are circulating in Brazilian commercial poultry flocks.


#5 - On the etiology of an outbreak of winter dysentery in dairy cows in Brazil, p.398-402

Abstract in English:

ABSTRACT.- Brandão P.E., Laura Y. B. Villarreal L.Y.B., F.Gregori F., Souza S.L.P., Lopes M.A.E., Gomes C.R., Sforsin A.J., Sanches A.A., Rosales C.A.R., Richtzenhain L.J., Ferreira A.J.P. & Jerez J.A. 2007. On the etiology of an outbreak of winter dysentery in dairy cows in Brazil. Pesquisa Veterinária Brasileira 27(10):398-402. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: paulo7926@yahoo.com Winter dysentery (WD) is a seasonal infectious disease described worldwide that causes a marked decrease in milk production in dairy cows. In the Northern hemisphere, where the disease is classically recognized, bovine coronavirus (BCoV) has been assigned as a major etiologic agent of the disease. Nonetheless, in the Southern hemisphere, an in-deep etiological survey on WD cases had not been carried out. This study aimed to survey for BCoV by nested-RT-PCR, rotavirus by polyacrylamide gel electrophoresis (PAGE) and ELISA, bacteria by classical bacteriological methods and PCR for virulence factors and parasites by sugar flotation test on fecal samples of 21 cows from a farm during an outbreak of WD in São Paulo state, Southeastern Brazil. BCoV was detected in all 21 samples, while rotavirus was detected in two symptomatic cows. Escherichia coli, Yersinia intermedia, Providencia rustigianii Proteus penneri, Klebsiella terrigena and Enterobacter aglomerans were detected in samples from both asymptomatic and healthy cows in different associations. The study of E. coli virulence factors revealed that the strains isolated were all apathogenic. Cysts of Eimeria sp. and eggs of Strongyloidea were detected at low numbers in four of the symptomatic cows, with one co-infestation. These results suggest BCoV as the main etiologic agent of the cases of WD in Brazil, a conclusion that, with the clinical and epidemiological patterns of the disease studied herein, match those already described elsewhere. These findings give basis to the development of preventive measures and contribute to the understanding of the etiology of WD.

Abstract in Portuguese:

ABSTRACT.- Brandão P.E., Laura Y. B. Villarreal L.Y.B., F.Gregori F., Souza S.L.P., Lopes M.A.E., Gomes C.R., Sforsin A.J., Sanches A.A., Rosales C.A.R., Richtzenhain L.J., Ferreira A.J.P. & Jerez J.A. 2007. On the etiology of an outbreak of winter dysentery in dairy cows in Brazil. Pesquisa Veterinária Brasileira 27(10):398-402. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: paulo7926@yahoo.com Winter dysentery (WD) is a seasonal infectious disease described worldwide that causes a marked decrease in milk production in dairy cows. In the Northern hemisphere, where the disease is classically recognized, bovine coronavirus (BCoV) has been assigned as a major etiologic agent of the disease. Nonetheless, in the Southern hemisphere, an in-deep etiological survey on WD cases had not been carried out. This study aimed to survey for BCoV by nested-RT-PCR, rotavirus by polyacrylamide gel electrophoresis (PAGE) and ELISA, bacteria by classical bacteriological methods and PCR for virulence factors and parasites by sugar flotation test on fecal samples of 21 cows from a farm during an outbreak of WD in São Paulo state, Southeastern Brazil. BCoV was detected in all 21 samples, while rotavirus was detected in two symptomatic cows. Escherichia coli, Yersinia intermedia, Providencia rustigianii Proteus penneri, Klebsiella terrigena and Enterobacter aglomerans were detected in samples from both asymptomatic and healthy cows in different associations. The study of E. coli virulence factors revealed that the strains isolated were all apathogenic. Cysts of Eimeria sp. and eggs of Strongyloidea were detected at low numbers in four of the symptomatic cows, with one co-infestation. These results suggest BCoV as the main etiologic agent of the cases of WD in Brazil, a conclusion that, with the clinical and epidemiological patterns of the disease studied herein, match those already described elsewhere. These findings give basis to the development of preventive measures and contribute to the understanding of the etiology of WD.


#6 - Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region

Abstract in English:

ABSTRACT.- Cortez A., Heinemann M.B., Castro A.M.M.G., Soares M.S, Pinto A.M.V., Alfieri A.A., Flores E.F., Leite R.C. & Richtzenhain L.J. 2006. Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region. Pesquisa Veterinária Brasileira 26(4):211-216. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Nineteen isolates of bovine viral diarrhea virus (BVDV) from Brazil were genetically characterized through partial nucleotide sequencing and analysis of the 5’UTR region. The isolates were grouped as BVDV-1 (11/19), BVDV-2 (6/19) or “atypical” pestivirus (2/19). Among the BVDV-1, eight isolates were classified as subgenotype BVDV-1a, whereas most (4 out of 6) BVDV-2 belonged to subgenotype 2b. Two isolates from aborted fetuses were not classified into any genetic group, being considered atypical BVDVs. Genetic diversity among Brazilian BVDV isolates may be responsible for vaccination and diag-nostic failure and therefore may influence the control strategies for BVDV infection in the country.

Abstract in Portuguese:

ABSTRACT.- Cortez A., Heinemann M.B., Castro A.M.M.G., Soares M.S, Pinto A.M.V., Alfieri A.A., Flores E.F., Leite R.C. & Richtzenhain L.J. 2006. Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region. Pesquisa Veterinária Brasileira 26(4):211-216. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Nineteen isolates of bovine viral diarrhea virus (BVDV) from Brazil were genetically characterized through partial nucleotide sequencing and analysis of the 5’UTR region. The isolates were grouped as BVDV-1 (11/19), BVDV-2 (6/19) or “atypical” pestivirus (2/19). Among the BVDV-1, eight isolates were classified as subgenotype BVDV-1a, whereas most (4 out of 6) BVDV-2 belonged to subgenotype 2b. Two isolates from aborted fetuses were not classified into any genetic group, being considered atypical BVDVs. Genetic diversity among Brazilian BVDV isolates may be responsible for vaccination and diag-nostic failure and therefore may influence the control strategies for BVDV infection in the country.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV