PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Santos M.B., Martini M.C., Ferreira H.L., Silva L.H.A., Fellipe P.A., Spilki F.R. & Arns C.W. 2012. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy. Pesquisa Veterinária Brasileira 32(12):1257-1262. Laboratório de Virologia, Instituto de Biologia, Universidade Estadual de Campinas, Rua Monteiro Lobato s/n, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: arns@unicamp.br Avian metapneumovirus (aMPV) is a respiratory pathogen associated with the swollen head syndrome (SHS) in chickens. In Brazil, live aMPV vaccines are currently used, but subtypes A and, mainly subtype B (aMPV/A and aMPV/B) are still circulating. This study was conducted to characterize two Brazilian aMPV isolates (A and B subtypes) of chicken origin. A challenge trial to explore the replication ability of the Brazilian subtypes A and B in chickens was performed. Subsequently, virological protection provided from an aMPV/B vaccine against the same isolates was analyzed. Upon challenge experiment, it was shown by virus isolation and real time PCR that aMPV/B could be detected longer and in higher amounts than aMPV/A. For the protection study, 18 one-day-old chicks were vaccinated and challenged at 21 days of age. Using virus isolation and real time PCR, no aMPV/A was detected in the vaccinated chickens, whereas one vaccinated chicken challenged with the aMPV/B isolate was positive. The results showed that aMPV/B vaccine provided a complete heterologous virological protection, although homologous protection was not complete in one chicken. Although only one aMPV/B positive chicken was detected after homologous vaccination, replication in vaccinated animals might allow the emergence of escape mutants.

• Avian metapneumovirus vaccine protection Metapneumovirus aviário

Abstract in Portuguese:

RESUMO.- Santos M.B., Martini M.C., Ferreira H.L., Silva L.H.A., Fellipe P.A., Spilki F.R. & Arns C.W. 2012. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy. Pesquisa Veterinária Brasileira 32(12):1257-1262. Laboratório de Virologia, Instituto de Biologia, Universidade Estadual de Campinas, Rua Monteiro Lobato s/n, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: arns@unicamp.br O Metapneumovírus aviário (aMPV) é um patógeno respiratório associado à síndrome da cabeça inchada (SHS) em galinhas. Apesar de vacinas vivas contra o aMPV serem utilizadas no Brasil, os subtipos A e B (aMPV/A e aMPV/B) são ainda encontrados no país, com predominância do subtipo B. Este estudo foi conduzido com o intuito de estudar dois isolados brasileiros de aMPV (subtipos A e B) isolados de frango. Para isto, um desafio experimental em frangos foi conduzido com o intuito de explorar a capacidade de replicação dos subtipos A e B Brasileiros. Posteriormente, a protecção virológica conferida por uma vacina do subtipo B em pintos foi realizada com os mesmos isolados. Após o desafio experimental demonstrou-se, por isolamento viral e PCR em tempo real, que o isolado do subtipo B replicou por maior período de tempo e em quantidades maiores, em comparação com o subtipo A. Para o estudo de proteção, 18 pintos de um dia de idade foram vacinados e desafiados aos 21 dias. Usando isolamento viral e PCR em tempo real, em nenhuma ave vacinada e desafiada com aMPV/A foi detectado o vírus, ao passo que uma ave vacinada e desafiada com o aMPV/B foi positiva. Os resultados mostraram que a vacina do subtipo B forneceu protecção heteróloga completa, embora a protecção homóloga não tenha sido conferida em uma ave. Apesar de o aMPV/B ter sido detectado em apenas um frango após vacinação homóloga, a replicação viral em aves vacinadas pode resultar em emergência de mutantes de escape.

Abstract in English:

ABSTRACT.- Vitale P.A.M., Crepaldi C.R., Tesch A.C., Albuquerque R. & César M.C. 2012. [Purification and characterization of avian cortical mitochondrial VDAC: identification of post-translational modifications of rat and avian neuronal porins.] Purificação e caracterização da VDAC de mitocôndrias corticais aviares: identificação de modificações pós-traducionais nas porinas neuronais murinas e aviares. Pesquisa Veterinária Brasileira 32(12):1361-1366. Laboratório de Neurociência e Proteômica, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Av. Duque de Caxias Norte 225, Pirassununga, SP 13635-900, Brazil. E-mail: mccesar@usp.br VDAC (voltage-dependent anion channel) is a pore forming protein from outer mitochondrial membrane. It has key functions on energetic metabolism, and cell death and survival. VDAC characterization is important for understanding mitochondrial interactions with cytosolic proteins, such as hexokinase (HK). HK-VDAC interaction supports preferential access to intramitochondrial ATP in neural cells. Brain HK interacts in different ways with VDAC. It results in two HK binding sites (A and B). VDAC isoforms differential metabolic roles may be explained by the presence of post-translational modifications. In this study we purified avian neuronal mitochondrial VDAC1. At same time we showed that VDACs 1 and 2 pI heterogeneity in rat and avian brains is due to phosphorylation. Purified VDAC had a molecular weight of 30 KDa. The purified VDAC submitted to phosphorylated protein staining on gel, was dephosphorylated. The knowledge of presence or absence of VDAC phosphorylation is important for understanding the molecular nature basis of A and B HK binding sites in brain mitochondria.

• VDAC hexokinase phosphorylation mitochondria hexoquinase fosforilação mitocôndria

Abstract in Portuguese:

RESUMO.- Vitale P.A.M., Crepaldi C.R., Tesch A.C., Albuquerque R. & César M.C. 2012. [Purification and characterization of avian cortical mitochondrial VDAC: identification of post-translational modifications of rat and avian neuronal porins.] Purificação e caracterização da VDAC de mitocôndrias corticais aviares: identificação de modificações pós-traducionais nas porinas neuronais murinas e aviares. Pesquisa Veterinária Brasileira 32(12):1361-1366. Laboratório de Neurociência e Proteômica, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Av. Duque de Caxias Norte 225, Pirassununga, SP 13635-900, Brazil. E-mail: mccesar@usp.br A VDAC é uma porina presente na MME cuja função é crucial no metabolismo energético, sobrevivência e morte celular. A caracterização da VDAC torna-se importante para a compreensão das inter-relações da mitocôndria com os diferentes componentes citosólicos, tais como a HK. A ligação HK-VDAC favorece a utilização do ATP intramitocondrial em células neuronais, a HK cerebral pode interagir de formas diferentes com a VDAC, o que resulta em diferentes sítios de ligação (sítios A e B). Os variados papéis metabólicos das isoformas da VDAC podem ser explicados pela presença de alterações pós-traducionais. No presente trabalho purificamos a VDAC1 mitocondrial neuronal proveniente de cérebro aviar. Paralelamente, comprovamos que a presença de múltiplas formas das VDACs 1 e 2 em cérebros murino e aviar, seja devida à presença de modificações pós-traducionais, nomeadamente a fosforilação. A proteína isolada apresentou peso molecular de 30KDa. Quando submetida à eletroforese e posteriormente à coloração para a identificação de fosfoproteínas, a mesma mostrou-se desfosforilada. O conhecimento da presença, ou ausência de fosforilação das VDACs, reside na importância de estabelecer-se as bases moleculares ligadas à existência de sítios A e B nas mitocôndrias neuronais.

Abstract in English:

ABSTRACT.- Reck C., Menin A. , Pilati C. & Miletti L.C. 2012. [Clinical and histologic lesions of mixed infection with Avian orthoreovirus and Mycoplasma synoviae in broilers.] Características clínicas e anatomo-histopatologicas da infecção experimental mista por Orthoreovirus aviario e Mycoplasma synoviae em frangos de corte. Pesquisa Veterinária Brasileira 32(8):687-691. Laboratório de Bioquímica de Hemoparasitas e Vetores, Universidade do Estado de Santa Catarina, Avenida Luiz de Camões 1020, Lages, SC 88520-000, Brazil. E-mail: carolreck@gmail. com Infectious arthritis in broiler represents an economic and health problem resulting in severe losses due to retarded growth and down grading at slaughterhouse. The most common agents associated with cases of infectious arthritis in poultry are Mycoplasma synoviae and Avian orthoreovirus. This study proposed to investigate the histopathological changes caused by mixed infection with Mycoplasma synoviae and Avian orthoreovirus in broilers and confirm the presence of the agents through PCR and immunofluorescence assay (IFA). We used 16 broiler chickens, housed in bed, with supply of food and water ad libitum. Ten-day-old broilers were infected with Mycoplasma synoviae and Avian orthoreovirus. Clinically, they showed lethargy and swelling of the hock joint. After 30 days, we proceeded to their euthanasia and necropsy. Histological lesions were observed due to the mixed infection with Mycoplasma synoviae and Avian orthoreovirus in different tissues. The histopathology of the joints was characterized by infiltration of heterophil leucocytes in the synovial membrane and the digital flexor tendon. The inflammatory process was also found in trachea, lungs, air sac, liver, spleen, pericardium and proventriculus. The use of IFA was necessary to verify the presence of both agents in the hock joints, identifying the antigens of Mycoplasma synoviae and Avian orthoreovirus. The presence of M. synoviae was detected by PCR in trachea, lung, air sacs, synovial membrane and synovial fluid. Avian orthoreovirus was detected with PCR in liver, spleen, synovial membrane and digital flexor tendon. In conclusion, this investigation suggests that a synergistic relationship exists between Mycoplasma synoviae and Avian orthoreovirus.

• Arthritis Mycoplasma synoviae Avian orthoreovirus Artrite Mycoplasma synovia Orthoreovirus aviário

Abstract in Portuguese:

RESUMO.- Reck C., Menin A. , Pilati C. & Miletti L.C. 2012. [Clinical and histologic lesions of mixed infection with Avian orthoreovirus and Mycoplasma synoviae in broilers.] Características clínicas e anatomo-histopatologicas da infecção experimental mista por Orthoreovirus aviario e Mycoplasma synoviae em frangos de corte. Pesquisa Veterinária Brasileira 32(8):687-691. Laboratório de Bioquímica de Hemoparasitas e Vetores, Universidade do Estado de Santa Catarina, Avenida Luiz de Camões 1020, Lages, SC 88520-000, Brazil. E-mail: carolreck@gmail. com A artrite infecciosa em frangos de corte representa um problema sanitário e econômico de grande impacto, provocando perdas de produtividade e nos processos de produção e industrialização. Os principais agentes etiológicos associados aos casos de artrites e tenossinovites infecciosas em aves são Mycoplasma synoviae (MS) e Orthoreovirus aviario (ARV). Esse trabalho propôs investigar as alterações anatomohistopatológicas causadas pela infecção experimental concomitante por Mycoplasma synoviae e Orthoreovirus aviario em frangos de corte e confirmar a presença dos agentes através das técnicas de PCR e imunofluorescência indireta (RIFI). Para tal foram utilizados 16 frangos de corte, alojados em cama, com fornecimento de ração e água ad libitum. A infecção experimental foi realizada utilizando amostras atenuadas de MS e de ARV. Clinicamente as aves inoculadas apresentaram apatia e edemaciação da região da articulação tíbiotársica. Após 30 dias procedeu-se a eutanásia e a necropsia das aves. Na análise histopatológica constatou-se o efeito da infecção mista com MS e ARV sobre os diferentes órgãos/tecidos. Todos os animais apresentaram quadro de artrite e tenossinovite caracterizado pela presença de infiltrado inflamatório linfohistiocitário difuso, com acúmulo de heterófilos na cápsula articular/membrana sinovial e tendão flexor digital. Além disso, foi possível observar infiltrado inflamatório na traquéia, nos pulmões e sacos aéreos, no fígado, baço, pericárdio e proventrículo. A utilização da RIFI foi necessária para visualizar a presença de ambos os agentes nas articulações, identificando a presença de antígenos do ARV e do MS. A técnica de PCR constatou positividade do MS na traquéia, pulmões/sacos aéreos, cápsula articular/membrana sinovial e liquido sinovial. Já para o ARV a PCR foi positiva em amostras de fígado, baço, cápsula articular/membrana sinovial e tendão flexor digital. Com base nas lesões observadas e nos dados da literatura, sugere-se a ação concomitante por MS e ARV nos diferentes tecidos.

Abstract in English:

BSTRACT.- Gilberto D. Vargas G.D., Albano A.P., Fischer G., Hübner S., Sallis S.E., Nunes C.F., Raffi M.B. & Soares M.P. 2011. Avian pox virus infection in a common barn owl (Tyto alba) in southern Brazil. Pesquisa Veterinária Brasileira 31(7):620-622. Laboratório de Virologia e Imunologia, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: gdavilavargas@gmail.com A young common barn owl (Tyto alba) was referred to the Núcleo de Reabilitação da Fauna Silvestre (Nurfs), Federal University of Pelotas (UFPel), after been found in a barn of a brick factory in the urban area of Pelotas, Rio Grande do Sul, Brazil. The bird was apathic, weak and with crusty lesions in the featherless areas (eyes, beak, legs), and died soon after arrival at Nurfs. Necropsy and histopathological examination of the lesions were carried out. The hyperplasia and hypertrophy of the cutaneous lesions, several eosinophilic intracyto-plasmic inclusion bodies in epithelial cells (Bollinger bodies), as well as particles characteristic of poxvirus, observed by electronic microscopy, confirmed the infection by avian poxvirus, what highlights the importance of Tyto alba as carrier of the virus in the wild.

• Tyto alba common barn owl avian pox virus bouba aviária

Abstract in Portuguese:

RESUMO.- Gilberto D. Vargas G.D., Albano A.P., Fischer G., Hübner S., Sallis S.E., Nunes C.F., Raffi M.B. & Soares M.P. 2011. Avian pox virus infection in a common barn owl (Tyto alba) in southern Brazil. Pesquisa Veterinária Brasileira 31(7):620-622. Laboratório de Virologia e Imunologia, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: gdavilavargas@gmail.com Uma coruja-de-igreja (Tyto alba) em idade juvenil foi encaminha ao Núcleo de Reabilitação da Fauna Silvestre (Nurfs), Universidade Federal de Pelotas (UFPel), após ter sido encontrada num galpão de uma olaria na região urbana da cidade de Pelotas, RS. A ave apresentava-se apática, debilitada e com lesões crostosas nas áreas sem penas do corpo (olhos, patas e bico), e morreu logo após a chegada ao Nurfs. Foram realizados necropsia e exame histopatológico. A presença de hiperplasia e hipertrofia epidérmica nas lesões cutâneas, várias inclusões intracitoplasmáticas eosinofílicas nas células epiteliais (Corpúsculos de Bollinger), assim como partículas características de poxvirus, demonstradas por microscopia eletrônica, confirmaram a infecção por poxvirus aviário, o que ressalta a importância da espécie Tyto alba como portadora do vírus na natureza.

Abstract in English:

ABSTRACT.- Nakazato G., Campos T.A., Stehling E.G., Brocchi M. & Silveira W.D. 2009. Virulence factors of avian pathogenic Escherichia coli (APEC). Pesquisa Veterinária Brasileira 29(7):479-486. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (Unicamp), Cidade Universitária Zeferino Vaz s/n, Cx. Postal 6109, Barão Geraldo, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br Avian pathogenic Escherichia coli (APEC) strains cause a great diversity of diseases in birds and are responsible for great economic losses in the avian industry. To date, several studies have been carried out to better understand the APEC pathogenesis for a possible development of tools which could prevent the economics losses caused by these strains. This review discusses the virulence factors described do date to be expressed by these strains and the advances made to understand and identify virulence determinants present in APEC.

• APEC avian Escherichia coli virulence factors

Abstract in Portuguese:

RESUMO.- Nakazato G., Campos T.A., Stehling E.G., Brocchi M. & Silveira W.D. 2009. Virulence factors of avian pathogenic Escherichia coli (APEC). [Fatores de virulência de Escherichia coli aviária patogênica (APEC).] Pesquisa Veterinária Brasileira 29(7):479-486. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (Unicamp), Cidade Universitária Zeferino Vaz s/n, Cx. Postal 6109, Barão Geraldo, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br Linhagens de Escherichia coli patogênicas para aves (APEC) causam uma grande diversidade de doenças em aves e são responsáveis por grandes prejuízos na indústria aviária. Nos últimos anos, vários estudos foram realizados para melhor entender a patogênese de linhagens APEC e para desenvolver ferramentas que podem prevenir as perdas econômicas causadas por estas linhagens. Esta revisão discute os fatores de virulência descritos nestas linhagens e os avanços realizados para entender e identificar os determinantes de virulência presentes em APEC.

Abstract in English:

ABSTRACT.- Campos T.A., Nakazato G., Stehling E.G., Brocchi M. & Silveira W.D. 2008. Clonal study of avian Escherichia coli strains by fliC conserved-DNA-sequence regions analysis. Pesquisa Veterinária Brasileira 28(10):508-514. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Cx. Postal 6109, Universidade Estadual de Campinas, Cidade Universitária Zeferino Vaz s/n, Barão Geraldo, Campinas, SP 3081-862, Brazil. *Corresponding author: wds@unicamp.br The clonal relationship among avian Escherichia coli strains and their genetic proximity with human pathogenic E. coli, Salmonela enterica, Yersinia enterocolitica and Proteus mirabilis, was determined by the DNA sequencing of the conserved 5’ and 3’regions fliC gene (flagellin encoded gene). Among 30 commensal avian E. coli strains and 49 pathogenic avian E. coli strains (APEC), 24 commensal and 39 APEC strains harbored fliC gene with fragments size varying from 670bp to 1,900bp. The comparative analysis of these regions allowed the construction of a dendrogram of similarity possessing two main clusters: one compounded mainly by APEC strains and by H-antigens from human E. coli, and another one compounded by commensal avian E. coli strains, S. enterica, and by other H-antigens from human E. coli. Overall, this work demonstrated that fliC conserved regions may be associated with pathogenic clones of APEC strains, and also shows a great similarity among APEC and H-antigens of E. coli strains isolated from humans. These data, can add evidence that APEC strains can exhibit a zoonotic risk.

• APEC clonal analysis fliC gene

Abstract in Portuguese:

ABSTRACT.- Campos T.A., Nakazato G., Stehling E.G., Brocchi M. & Silveira W.D. 2008. Clonal study of avian Escherichia coli strains by fliC conserved-DNA-sequence regions analysis. Pesquisa Veterinária Brasileira 28(10):508-514. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Cx. Postal 6109, Universidade Estadual de Campinas, Cidade Universitária Zeferino Vaz s/n, Barão Geraldo, Campinas, SP 3081-862, Brazil. *Corresponding author: wds@unicamp.br The clonal relationship among avian Escherichia coli strains and their genetic proximity with human pathogenic E. coli, Salmonela enterica, Yersinia enterocolitica and Proteus mirabilis, was determined by the DNA sequencing of the conserved 5’ and 3’regions fliC gene (flagellin encoded gene). Among 30 commensal avian E. coli strains and 49 pathogenic avian E. coli strains (APEC), 24 commensal and 39 APEC strains harbored fliC gene with fragments size varying from 670bp to 1,900bp. The comparative analysis of these regions allowed the construction of a dendrogram of similarity possessing two main clusters: one compounded mainly by APEC strains and by H-antigens from human E. coli, and another one compounded by commensal avian E. coli strains, S. enterica, and by other H-antigens from human E. coli. Overall, this work demonstrated that fliC conserved regions may be associated with pathogenic clones of APEC strains, and also shows a great similarity among APEC and H-antigens of E. coli strains isolated from humans. These data, can add evidence that APEC strains can exhibit a zoonotic risk.

Abstract in English:

ABSTRACT.- Lisbôa R.S., Guedes Júnior D.S., Silva F.J.M., Cunha N.C., Machado C.H. & Fonseca A.H. 2008. [Alterations in hematological parameters of Gallus gallus domesticus experimentally infected with Borrelia anserina.] Alterações nos parâmetros hematológicos de Gallus gallus domesticus experimentalmente infectados por Borrelia anserina. Pesquisa Veterinária Brasileira 28(10):527-532. Curso de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: raquellisboa@ufrrj.br Avian spirochaetosis is a cosmopolite acute septicemic disease of many avian species, caused by Borrelia anserina Sakharoff, 1891. The present study assesses the estimate of the hematological alterations of Gallus gallus domesticus experimentally infected with B. anserina by vector Argas (Persicargas) miniatus. Twenty-seven fowls of the species G. g. domesticus, 67 days old, were randomly allocated into three groups composed by nine animals each. One group was exposed to B. anserina infected ticks (Group 1), other one to ticks free of this agent (Group 2), and another group not exposed to ticks (Group 3). Blood smears of the fowls were taken daily, since the first day the fowls were exposed to the ticks, up to the 25th day after exposure (DAE). Blood samples were collected three days before exposure, and three, eight and 18 DAE, for hematologic tests. The examination of Group 1 smears revealed large number of spirochaetes. Group 2 and 3 blood smears were negative during the whole period under exam. In agreement with the hematological evaluation results, the fowls exposed to infected ticks showed a normocytic normochromic anemia in eight DAE, leucocytosis with heterophilia and monocytosis concomitant with the spirochaetemia. We concluded that B. anserina infection determined on fowls of Group 1 hematological alterations compatible with bacterial infection of moderate gravity, developing to self-cure, in the experimental conditions established in this study.

• Borrelia anserina Argas (Persicargas) miniatus avian hematology domestic fowls avian spirochaetosis

Abstract in Portuguese:

ABSTRACT.- Lisbôa R.S., Guedes Júnior D.S., Silva F.J.M., Cunha N.C., Machado C.H. & Fonseca A.H. 2008. [Alterations in hematological parameters of Gallus gallus domesticus experimentally infected with Borrelia anserina.] Alterações nos parâmetros hematológicos de Gallus gallus domesticus experimentalmente infectados por Borrelia anserina. Pesquisa Veterinária Brasileira 28(10):527-532. Curso de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: raquellisboa@ufrrj.br Avian spirochaetosis is a cosmopolite acute septicemic disease of many avian species, caused by Borrelia anserina Sakharoff, 1891. The present study assesses the estimate of the hematological alterations of Gallus gallus domesticus experimentally infected with B. anserina by vector Argas (Persicargas) miniatus. Twenty-seven fowls of the species G. g. domesticus, 67 days old, were randomly allocated into three groups composed by nine animals each. One group was exposed to B. anserina infected ticks (Group 1), other one to ticks free of this agent (Group 2), and another group not exposed to ticks (Group 3). Blood smears of the fowls were taken daily, since the first day the fowls were exposed to the ticks, up to the 25th day after exposure (DAE). Blood samples were collected three days before exposure, and three, eight and 18 DAE, for hematologic tests. The examination of Group 1 smears revealed large number of spirochaetes. Group 2 and 3 blood smears were negative during the whole period under exam. In agreement with the hematological evaluation results, the fowls exposed to infected ticks showed a normocytic normochromic anemia in eight DAE, leucocytosis with heterophilia and monocytosis concomitant with the spirochaetemia. We concluded that B. anserina infection determined on fowls of Group 1 hematological alterations compatible with bacterial infection of moderate gravity, developing to self-cure, in the experimental conditions established in this study.

Abstract in English:

ABSTRACT.- Campos T.A., Lago J.C., Nakazato G., Stehling E.G., Brocchi M., Castro A.F.P. & Silveira W.D. 2008. Occurrence of virulence-related sequences and phylogenetic analysis of commensal and pathogenic avian Escherichia coli strains (APEC). Pesquisa Veterinária Brasileira 28(10):533-540. Departamento de Microbiologia e Immunologia, Instituto de Biologia, Unicamp, Cidade Universitrária Zeferino Vaz s/n, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br The presence of iron uptake (irp-2, fyuA, sitA, fepC, iucA), adhesion (iha, lpfAO157/O141, lpfAO157/O154, efa, toxB) and invasion (inv, ial-related DNA sequences and assignment to the four main Escherichia coli phylogenetic groups (A, B1, B2 e D) were determined in 30 commensal E. coli strains isolated from healthy chickens and in 49 APEC strains isolated from chickens presenting clinical signs of septicemia (n=24) swollen head syndrome (n=14) and omphalitis (n=11) by PCR. None of the strains presented DNA sequences related to the inv, ial, efa, and toxB genes. DNA sequences related to lpfAO157/O154, iucA, fepC, and irp-2 genes were significantly found among pathogenic strains, where iucA gene was associated with septicemia and swollen head syndrome and fepC and irp-2 genes were associated with swollen head syndrome strains. Phylogenetic typing showed that commensal and omphalitis strains belonged mainly to phylogenetic Group A and swollen head syndrome to phylogenetic Group D. Septicemic strains were assigned in phylogenetic Groups A and D. These data could suggest that clonal lineage of septicemic APEC strains have a multiple ancestor origin; one from a pathogenic bacteria ancestor and other from a non-pathogenic ancestor that evolved by the acquisition of virulence related sequences through horizontal gene transfer. Swollen head syndrome may constitute a pathogenic clonal group. By the other side, omphalitis strains probably constitute a non-pathogenic clonal group, and could cause omphalitis as an opportunistic infection. The sharing of virulence related sequences by human pathogenic E. coli and APEC strains could indicate that APEC strains could be a source of virulence genes to human strains and could represent a zoonotic risk.

• Avian colibacillosis Escherichia coli APEC virulence related-genes pathogenic clones

Abstract in Portuguese:

ABSTRACT.- Campos T.A., Lago J.C., Nakazato G., Stehling E.G., Brocchi M., Castro A.F.P. & Silveira W.D. 2008. Occurrence of virulence-related sequences and phylogenetic analysis of commensal and pathogenic avian Escherichia coli strains (APEC). Pesquisa Veterinária Brasileira 28(10):533-540. Departamento de Microbiologia e Immunologia, Instituto de Biologia, Unicamp, Cidade Universitrária Zeferino Vaz s/n, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br The presence of iron uptake (irp-2, fyuA, sitA, fepC, iucA), adhesion (iha, lpfAO157/O141, lpfAO157/O154, efa, toxB) and invasion (inv, ial-related DNA sequences and assignment to the four main Escherichia coli phylogenetic groups (A, B1, B2 e D) were determined in 30 commensal E. coli strains isolated from healthy chickens and in 49 APEC strains isolated from chickens presenting clinical signs of septicemia (n=24) swollen head syndrome (n=14) and omphalitis (n=11) by PCR. None of the strains presented DNA sequences related to the inv, ial, efa, and toxB genes. DNA sequences related to lpfAO157/O154, iucA, fepC, and irp-2 genes were significantly found among pathogenic strains, where iucA gene was associated with septicemia and swollen head syndrome and fepC and irp-2 genes were associated with swollen head syndrome strains. Phylogenetic typing showed that commensal and omphalitis strains belonged mainly to phylogenetic Group A and swollen head syndrome to phylogenetic Group D. Septicemic strains were assigned in phylogenetic Groups A and D. These data could suggest that clonal lineage of septicemic APEC strains have a multiple ancestor origin; one from a pathogenic bacteria ancestor and other from a non-pathogenic ancestor that evolved by the acquisition of virulence related sequences through horizontal gene transfer. Swollen head syndrome may constitute a pathogenic clonal group. By the other side, omphalitis strains probably constitute a non-pathogenic clonal group, and could cause omphalitis as an opportunistic infection. The sharing of virulence related sequences by human pathogenic E. coli and APEC strains could indicate that APEC strains could be a source of virulence genes to human strains and could represent a zoonotic risk.

Abstract in English:

ABSTRACT.- Rocha A.C.G.P., Rocha S.L.S., Lima-Rosa C.A.V., Souza G.F., Moraes H.L.S., Salle F.O., Moraes L.B. & Salle C.T.P. 2008. Genes associated with pathogenicity of avian Escherichia coli (APEC) isolated from respiratory cases of poultry. Pesquisa Veterinária Brasileira 28(3):183-186. Centro de Diagnóstico e Pesquisa em Patologia Aviária, Departamento de Medicina Animal, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 8824, Porto Alegre, RS 91540-000, Brazil. E-mail: ana.crocha@terra.com.br The virulence mechanisms of avian pathogenic Escherichia coli (APEC) have been continually studied and are believed to be multi-factorial. Certain properties are primarily associated with virulent samples and have been identified in avian isolates. In this study a total of 61 E. coli, isolates from chicken flocks with respiratory symptomatology, were probed by Polimerase Chain Reation (PCR) for the presence of genes responsible for the adhesion capacity, P fimbria (papC) e F11 fimbria (felA), colicin production (cvaC), aerobactin presence (iutA), serum resistance (iss), temperature-sensitive hemagglutinin (tsh), and presence of K1 and K5 capsular antigens (kpsII). The iss gene was detected in 73,8%, tsh in 55,7%, iutA in 45,9%, felA in 39,3%, papC in 24,3%, cvaC in 23% and kpsII in18%.

• Escherichia coli virulence PCR poultry pathogenicity

Abstract in Portuguese:

ABSTRACT.- Rocha A.C.G.P., Rocha S.L.S., Lima-Rosa C.A.V., Souza G.F., Moraes H.L.S., Salle F.O., Moraes L.B. & Salle C.T.P. 2008. Genes associated with pathogenicity of avian Escherichia coli (APEC) isolated from respiratory cases of poultry. Pesquisa Veterinária Brasileira 28(3):183-186. Centro de Diagnóstico e Pesquisa em Patologia Aviária, Departamento de Medicina Animal, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 8824, Porto Alegre, RS 91540-000, Brazil. E-mail: ana.crocha@terra.com.br The virulence mechanisms of avian pathogenic Escherichia coli (APEC) have been continually studied and are believed to be multi-factorial. Certain properties are primarily associated with virulent samples and have been identified in avian isolates. In this study a total of 61 E. coli, isolates from chicken flocks with respiratory symptomatology, were probed by Polimerase Chain Reation (PCR) for the presence of genes responsible for the adhesion capacity, P fimbria (papC) e F11 fimbria (felA), colicin production (cvaC), aerobactin presence (iutA), serum resistance (iss), temperature-sensitive hemagglutinin (tsh), and presence of K1 and K5 capsular antigens (kpsII). The iss gene was detected in 73,8%, tsh in 55,7%, iutA in 45,9%, felA in 39,3%, papC in 24,3%, cvaC in 23% and kpsII in18%.

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.

• Avian infectious bronchitis virus spike glycoprotein genotyping and RFLP

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.