Resultado da pesquisa (5)

Termo utilizado na pesquisa coronavírus

#1 - Seroepidemiological study of feline coronavirus (FCoV) infection in domiciled cats from Botucatu, São Paulo, Brazil

Abstract in English:

Feline coronavirus (FCoV) is responsible for causing one of the most important infectious diseases of domestic and wild felids, the feline infectious peritonitis (FIP), which is an immune-mediated, systemic, progressive and fatal disease. FCoV is highly contagious, and infection is common in domestic feline populations worldwide. The present study aimed to determine the seropositivity of FCoV infection and its associated epidemiological variables (risk factors) in domiciled cats in Botucatu, São Paulo, Brazil. Whole blood samples (0.5-1mL) were collected from 151 cats, and sera were extracted by centrifugation. These sera were tested by an commercial enzyme-linked immunosorbent assay (ELISA) for the detection of IgG anti-FCoV antibodies. The assessed risk factors were age range, breed, gender, reproductive status, outdoor access and rearing mode (living alone or in a group). The seropositivity was 64.2% (97/151). There was no statistical significance for risk factors related to breed, gender or rearing mode. There were significant differences in seropositivity (p-values ≤0.05) for age range (p=0.0157), reproductive status (p=0.0074) and outdoor access (p=0.0001). This study verified a wide dissemination of FCoV in the studied population, with a higher than expected seropositivity for indoor cats. Among the risk factors, age range, reproductive status and outdoor access presented statistically significant differences, thus helping to establish an epidemiological profile of this population.

Abstract in Portuguese:

O coronavírus felino (FCoV) é responsável por causar uma das mais importantes doenças infecciosas que acometem os felinos domésticos e selvagens, a peritonite infecciosa felina (PIF), que é uma enfermidade imunomediada, sistêmica, progressiva e fatal. O FCoV é altamente contagioso e a infecção é comum nas populações de felinos domésticos por todo o mundo. O presente estudo objetivou determinar a soropositividade da infecção pelo FCoV e correlacionar variáveis epidemiológicas (fatores de risco) de gatos domiciliados de Botucatu, São Paulo, Brasil. Amostras de sangue total (0,5 a 1mL) foram colhidas de 151 gatos e os soros foram obtidos após centrifugação. Estes soros foram testados por um teste commercial de ELISA para detecção de anticorpos IgG anti-FCoV. Os fatores de risco avaliados foram faixa etária, raça, gênero, condição reprodutiva, acesso à rua e modo de criação (viver solitário ou em grupo). Observou-se uma soropositividade de 64,2% (97/151). Não houve significância estatística para os fatores de risco relacionados à raça, gênero e modo de criação. Houve significância estatística quanto a soropositividade (p-values ≤0,05) para os fatores de risco faixa etária (p=0,0157), condição reprodutiva (p=0,0074) e acesso à rua (p=0,0001). Através do presente estudo verificou-se que o FCoV está amplamente disseminado na população estudada, onde a soropositividade encontrada foi maior do que a esperada para gatos domiciliados. Dentre os fatores de risco, faixa etária, condição reprodutiva e acesso à rua apresentaram diferenças estatisticamente significativas, contribuindo assim, para se estabelecer um perfil epidemiológico desta população.


#2 - Detection of coronavirus in diarrhea samples from water buffaloes (Bubalus bubalis) raised in the State of São Paulo, Brazil, 37(8):802-804

Abstract in English:

ABSTRACT.- Rossi R.S., Gaeta N.C., Gregori F. & Gregory L. 2017. [Detection of coronavirus in diarrhea samples from water buffaloes (Bubalus bubalis) raised in the State of São Paulo, Brazil.] Detecção de coronavírus em amostras de fezes diarreicas de búfalos (Bubalus bubalis) criados no Estado de São Paulo. Pesquisa Veterinária Brasileira 37(8):802-804. Departamento de Clínica Médica, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Professor Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: lgregory@usp.br Neonatal diarrhea can be a consequence of bacterial, endoparasite and viral infections. Although virus involved in diarrhea is frequently studied in cattle herds, there is lack of studies in Brazilian buffalo herds. The aim of this study was evaluate the presence of rotavirus and coronavirus in diarrhea samples of buffaloes (Bubalus buballis) raised on eight farms in Pariquera-açu, Registro, Pirassununga, Dourado, São João da Boa Vista e Congonhas, State of São Paulo, Brazil. We collected 40 diarrhea samples from water buffalo calves. While coronavirus was detected using nested polymerase chain reaction, rotavirus was detected using Polyacrylamide Gel Electrophoresis (PAGE) with silver stain. Rotavirus was not detected, while two samples (2/40, 5.0%) were positive for coronavirus. Although we did not detect rotavirus, a low percentage of coronavirus was observed; possible interference of these viruses in the development of diarrhea should not be discarded. Considering the lack of literature about diarrhea in water buffalo calves, particularly the one related with coronavirus, our results encourage new studies to enhance buffalo health in our country.

Abstract in Portuguese:

RESUMO.- Rossi R.S., Gaeta N.C., Gregori F. & Gregory L. 2017. [Detection of coronavirus in diarrhea samples from water buffaloes (Bubalus bubalis) raised in the State of São Paulo, Brazil.] Detecção de coronavírus em amostras de fezes diarreicas de búfalos (Bubalus bubalis) criados no Estado de São Paulo. Pesquisa Veterinária Brasileira 37(8):802-804. Departamento de Clínica Médica, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Professor Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: lgregory@usp.br A diarreia neonatal pode ser consequência de infecções bacterianas, endoparasitarárias e virais. Enquanto esses agentes virais são extensamente estudados nos rebanhos bovinos, faltam informações sobre a importância destes para os rebanhos bubalinos brasileiros. O objetivo deste trabalho foi avaliar a presença de rotavírus e coronavírus em amostras de fezes diarreicas de búfalos (Bubalus buballis) criados em oito propriedades localizadas em Pariquera-açu, Registro, Pirassununga, Dourado, São João da Boa Vista e Congonhas, Estado de São Paulo. Foram coletadas 40 amostras de fezes diarreicas de bezerros búfalos (Bubalus bubalis). A detecção de coronavírus foi realizada pela nested-PCR, enquanto que a detecção de rotavírus foi realizada pela Eletroforese em Gel de Poliacrilamida (PAGE) com coloração com nitrato de prata. Enquanto rotavírus não foi identificado, duas amostras (2/40, 5,0%) foram positivas para coronavírus. Embora no presente trabalho tenha havido baixa detecção de coronavírus e a ausência de rotavírus nos rebanhos estudados, a possível interferência desses vírus no desenvolvimento dos quadros diarreicos não deve ser descartada. Considerando o escasso material encontrado na literatura a respeito da diarreia em bezerros búfalos, principalmente aquele relativo ao coronavírus, nossos resultados são um incentivo para que novos estudos sejam realizados para impulsionar o desenvolvimento da bubalinocultura em nosso país.


#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 - Achados clínico patológicos durante um surto de disenteria de inverno em bovinos no Rio Grande do Sul, p.611-616

Abstract in English:

Abstract.- Pavarini S.P., Bezerra Junior P.S., Santos A.S., Pescador C.A. & Driemeier D. 2008. [Clinic pathological features during a winter dysentery outbreak in cattle in Rio Grande do Sul.] Achados clínico patológicos durante um surto de disenteria de inverno em bovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(12):611- 616. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br The report describes a winter dysentery outbreak that affected 10 dairy cows from a ranch located in the county of Viamão, Rio Grande do Sul. The most significant clinical sign was profuse and watery diarrhea, which ranged from a greenish to a brownish coloration and from occasional blood streaks with mucus to a bloody diarrhea. Most cases persisted for 5 days and also included depression, drastic decrease in milk production and in food consumption. Only one of the affected animals died. The necropsy revealed pale mucosa and sanguineous content with high quantity of blood clots, particularly within the spiral colon, and petechiae on the colonic mucosa. Histopathological lesions were predominant in the spiral colon, and consisted of a high number of dilated crypts without epithelium or with the replacement of a pavement epithelium with occasional immature cuboidal cells, which sometimes showed enlarged nucleus and proeminent nucleolus. Some crypts were filled with epithelial desquamation and polymorphnuclear cells. Bovine coronavirus (8F2) monoclonal antibody was used for immunohistochemistry on sections of the spiral colon that showed positive reactions in the cytoplasm of the infected crypt epithelium, sloughed necrotic cells, and within macrophages in the lamina propria of both.

Abstract in Portuguese:

Abstract.- Pavarini S.P., Bezerra Junior P.S., Santos A.S., Pescador C.A. & Driemeier D. 2008. [Clinic pathological features during a winter dysentery outbreak in cattle in Rio Grande do Sul.] Achados clínico patológicos durante um surto de disenteria de inverno em bovinos no Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(12):611- 616. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br The report describes a winter dysentery outbreak that affected 10 dairy cows from a ranch located in the county of Viamão, Rio Grande do Sul. The most significant clinical sign was profuse and watery diarrhea, which ranged from a greenish to a brownish coloration and from occasional blood streaks with mucus to a bloody diarrhea. Most cases persisted for 5 days and also included depression, drastic decrease in milk production and in food consumption. Only one of the affected animals died. The necropsy revealed pale mucosa and sanguineous content with high quantity of blood clots, particularly within the spiral colon, and petechiae on the colonic mucosa. Histopathological lesions were predominant in the spiral colon, and consisted of a high number of dilated crypts without epithelium or with the replacement of a pavement epithelium with occasional immature cuboidal cells, which sometimes showed enlarged nucleus and proeminent nucleolus. Some crypts were filled with epithelial desquamation and polymorphnuclear cells. Bovine coronavirus (8F2) monoclonal antibody was used for immunohistochemistry on sections of the spiral colon that showed positive reactions in the cytoplasm of the infected crypt epithelium, sloughed necrotic cells, and within macrophages in the lamina propria of both.


#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.


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