RESUMO
PURPOSE: Enzootic bovine leucosis (EBL) is a silent disease caused by a retrovirus [bovine leukaemia virus (BLV)]. BLV is classified into almost 10 genotypes that are distributed in several countries. The present research aimed to describe two BLV gp51 env sequences of strains detected in the state of São Paulo, Brazil and perform a phylogenetic analysis to compare them to other BLV gp51 env sequences of strains around the world. METHODOLOGY: Two bovines from different herds were admitted to the Bovine and Small Ruminant Hospital, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil. In both, lymphosarcoma was detected and the presence of BLV was confirmed by nested PCR. The neighbour-joining algorithm distance method was used to genotype the BLV sequences by phylogenetic reconstruction, and the maximum likelihood method was used for the phylogenetic reconstruction. The phylogeny estimates were calculated by performing 1000 bootstrap replicates. RESULTS: Analysis of the partial envelope glycoprotein (env) gene sequences from two isolates (25 and 31) revealed two different genotypes of BLV. Isolate 25 clustered with ten genotype 6 isolates from Brazil, Argentina, Thailand and Paraguay. On the other hand, isolate 31 clustered with two genotype 5 isolates (one was also from São Paulo and one was from Costa Rica). The detected genotypes corroborate the results of previous studies conducted in the state of São Paulo, Brazil. The prediction of amino acids showed substitutions, particularly between positions 136 and 150 in 11 out of 13 sequences analysed, including sequences from GenBank. CONCLUSION: BLV is still important in Brazil and this research should be continued.
Assuntos
Bovinos/virologia , DNA Viral/isolamento & purificação , Leucose Enzoótica Bovina/epidemiologia , Vírus da Leucemia Bovina/genética , Sequência de Aminoácidos , Animais , Argentina , Sequência de Bases , Brasil , Costa Rica , DNA Viral/genética , Leucose Enzoótica Bovina/virologia , Técnicas de Genotipagem , Vírus da Leucemia Bovina/classificação , Vírus da Leucemia Bovina/isolamento & purificação , Filogeografia , TailândiaRESUMO
Background: Infections are caused by Bovine Viral Diarrhea Virus and still continue to be a worldwide plague in cattle industry. It is responsible for sudden death syndromes in adult cattle with high mortality rates, abortions, acute gastrointestinal and respiratory diseases. The BVDV infection occurs in early pregnancy (40-142 days), in immunosuppressed females or cows results in 100% of persistently infected (PI) calves that are seronegative and asymptomatic at birth. Evidences suggests that BVDV contributes to BRD complex potentiating secondary infections caused by Mannheimia haemolytica e Pasteurella multocida due to its immunosuppressive action. However, the farmers have often associated the respiratory syndrome with other infectious agents. This paper reports the attendance of dairy calves manifesting clinical signs of bronchopneumonia, which led to the screening of the persistently infected animals to control of the BVDV infection in the herd.Materials, Methods & Results: During the technical assistance, ten calves manifesting bronchopneumonia were selected to trans-tracheal lavage (TL) in order to identify possible infectious agents. Reverse transcription polymerase chain reaction (RT-PCR) detected the presence of BVDV in two heifers. Pasteurella multocida was the unique bacterial agent isolated from TL (5/10, 50%). These data motivated the technical team and produc
RESUMO
Background: Infections are caused by Bovine Viral Diarrhea Virus and still continue to be a worldwide plague in cattle industry. It is responsible for sudden death syndromes in adult cattle with high mortality rates, abortions, acute gastrointestinal and respiratory diseases. The BVDV infection occurs in early pregnancy (40-142 days), in immunosuppressed females or cows results in 100% of persistently infected (PI) calves that are seronegative and asymptomatic at birth. Evidences suggests that BVDV contributes to BRD complex potentiating secondary infections caused by Mannheimia haemolytica e Pasteurella multocida due to its immunosuppressive action. However, the farmers have often associated the respiratory syndrome with other infectious agents. This paper reports the attendance of dairy calves manifesting clinical signs of bronchopneumonia, which led to the screening of the persistently infected animals to control of the BVDV infection in the herd.Materials, Methods & Results: During the technical assistance, ten calves manifesting bronchopneumonia were selected to trans-tracheal lavage (TL) in order to identify possible infectious agents. Reverse transcription polymerase chain reaction (RT-PCR) detected the presence of BVDV in two heifers. Pasteurella multocida was the unique bacterial agent isolated from TL (5/10, 50%). These data motivated the technical team and produc
RESUMO
Background: Infections are caused by Bovine Viral Diarrhea Virus and still continue to be a worldwide plague in cattle industry. It is responsible for sudden death syndromes in adult cattle with high mortality rates, abortions, acute gastrointestinal and respiratory diseases. The BVDV infection occurs in early pregnancy (40-142 days), in immunosuppressed females or cows results in 100% of persistently infected (PI) calves that are seronegative and asymptomatic at birth. Evidences suggests that BVDV contributes to BRD complex potentiating secondary infections caused by Mannheimia haemolytica e Pasteurella multocida due to its immunosuppressive action. However, the farmers have often associated the respiratory syndrome with other infectious agents. This paper reports the attendance of dairy calves manifesting clinical signs of bronchopneumonia, which led to the screening of the persistently infected animals to control of the BVDV infection in the herd.Materials, Methods & Results: During the technical assistance, ten calves manifesting bronchopneumonia were selected to trans-tracheal lavage (TL) in order to identify possible infectious agents. Reverse transcription polymerase chain reaction (RT-PCR) detected the presence of BVDV in two heifers. Pasteurella multocida was the unique bacterial agent isolated from TL (5/10, 50%). These data motivated the technical team and produc
RESUMO
Background: Infections are caused by Bovine Viral Diarrhea Virus and still continue to be a worldwide plague in cattle industry. It is responsible for sudden death syndromes in adult cattle with high mortality rates, abortions, acute gastrointestinal and respiratory diseases. The BVDV infection occurs in early pregnancy (40-142 days), in immunosuppressed females or cows results in 100% of persistently infected (PI) calves that are seronegative and asymptomatic at birth. Evidences suggests that BVDV contributes to BRD complex potentiating secondary infections caused by Mannheimia haemolytica e Pasteurella multocida due to its immunosuppressive action. However, the farmers have often associated the respiratory syndrome with other infectious agents. This paper reports the attendance of dairy calves manifesting clinical signs of bronchopneumonia, which led to the screening of the persistently infected animals to control of the BVDV infection in the herd.Materials, Methods & Results: During the technical assistance, ten calves manifesting bronchopneumonia were selected to trans-tracheal lavage (TL) in order to identify possible infectious agents. Reverse transcription polymerase chain reaction (RT-PCR) detected the presence of BVDV in two heifers. Pasteurella multocida was the unique bacterial agent isolated from TL (5/10, 50%). These data motivated the technical team and produc
RESUMO
Background: Infections are caused by Bovine Viral Diarrhea Virus and still continue to be a worldwide plague in cattle industry. It is responsible for sudden death syndromes in adult cattle with high mortality rates, abortions, acute gastrointestinal and respiratory diseases. The BVDV infection occurs in early pregnancy (40-142 days), in immunosuppressed females or cows results in 100% of persistently infected (PI) calves that are seronegative and asymptomatic at birth. Evidences suggests that BVDV contributes to BRD complex potentiating secondary infections caused by Mannheimia haemolytica e Pasteurella multocida due to its immunosuppressive action. However, the farmers have often associated the respiratory syndrome with other infectious agents. This paper reports the attendance of dairy calves manifesting clinical signs of bronchopneumonia, which led to the screening of the persistently infected animals to control of the BVDV infection in the herd.Materials, Methods & Results: During the technical assistance, ten calves manifesting bronchopneumonia were selected to trans-tracheal lavage (TL) in order to identify possible infectious agents. Reverse transcription polymerase chain reaction (RT-PCR) detected the presence of BVDV in two heifers. Pasteurella multocida was the unique bacterial agent isolated from TL (5/10, 50%). These data motivated the technical team and produc
RESUMO
Background: Infections are caused by Bovine Viral Diarrhea Virus and still continue to be a worldwide plague in cattle industry. It is responsible for sudden death syndromes in adult cattle with high mortality rates, abortions, acute gastrointestinal and respiratory diseases. The BVDV infection occurs in early pregnancy (40-142 days), in immunosuppressed females or cows results in 100% of persistently infected (PI) calves that are seronegative and asymptomatic at birth. Evidences suggests that BVDV contributes to BRD complex potentiating secondary infections caused by Mannheimia haemolytica e Pasteurella multocida due to its immunosuppressive action. However, the farmers have often associated the respiratory syndrome with other infectious agents. This paper reports the attendance of dairy calves manifesting clinical signs of bronchopneumonia, which led to the screening of the persistently infected animals to control of the BVDV infection in the herd.Materials, Methods & Results: During the technical assistance, ten calves manifesting bronchopneumonia were selected to trans-tracheal lavage (TL) in order to identify possible infectious agents. Reverse transcription polymerase chain reaction (RT-PCR) detected the presence of BVDV in two heifers. Pasteurella multocida was the unique bacterial agent isolated from TL (5/10, 50%). These data motivated the technical team and produc
RESUMO
This paper describes the control, epidemiological, pathological, and molecular aspects of an outbreak of meningoencephalitis in calves due to bovine herpesvirus 5 at a feedlot with 540 animals in São Paulo State, Brazil. The introduction of new animals and contact between the resident animals and the introduced ones were most likely responsible for virus transmission. Bovine herpesvirus 1 vaccine was used, resulting in the efficacy of the outbreak control, although two bovine herpesvirus 1 positive animals, vaccinated and revaccinated, presented meningoencephalitis, thereby characterizing vaccinal failure.
Assuntos
Doenças dos Bovinos/epidemiologia , Infecções por Herpesviridae/epidemiologia , Herpesvirus Bovino 5/imunologia , Vacinas Virais/administração & dosagem , Agricultura , Animais , Anticorpos Antivirais/imunologia , Brasil , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/patologia , Surtos de Doenças , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/patologia , Herpesvirus Bovino 1/imunologia , Herpesvirus Bovino 1/patogenicidade , Herpesvirus Bovino 5/patogenicidade , Vacinas Virais/imunologiaRESUMO
Neosporosis is a parasitic disease that occurs in sheep and is associated with reproductive failure. The aim of this study was to verify seroprevalence of Neospora caninum antibodies in 12 sheep flocks in Uberlândia county, Minas Gerais, Brazil, using Indirect Immunofluorescence Assay (IFA). A total of 334 sheep blood samples were analyzed and an epidemiologic questionnaire was applied for each farm in order to correlate with risk factors of neosporosis: gender, age, breed, abortion problems, contact with cattle and dogs, and presence of wild canids. The prevalence of Neospora caninum antibodies in sheep was 8.1%, with titers ranging from 50 to 3200 and 83.3% of farms detected at least one ovine reactive. There was statistically significant difference in flocks with abortion problems associated with the presence of Neospora caninum antibodies (p 0.05).
A neosporose é uma doença parasitária que acomete os ovinos e está associada a perdas reprodutivas. O objetivo deste estudo foi verificar a prevalência de anticorpos anti-Neospora caninum em 12 rebanhos de ovinos do município de Uberlândia, MG, utilizando a Técnica de Imunofluorescência Indireta (RIFI). Foram analisadas 334 amostras de sangue e, em cada propriedade, aplicou-se um questionário epidemiológico para avaliar os fatores de risco envolvidos na transmissão desse protozoário: sexo, idade, raça, problemas de aborto, contato com bovinos e caninos e presença de canídeos silvestres. A prevalência de anticorpos anti-Neospora caninum em ovinos foi de 8,1%, com títulos variando de 50 a 3200 e 83,3% das propriedades apresentaram pelo menos um ovino reagente. Houve diferença estatística significativa para rebanhos com problemas de aborto associados à presença de anticorpos anti-Neospora caninum (p 0,05).
RESUMO
Neospora caninum, a cause of abortion and stillbirth in cattle, was studied by histology, immunohistochemistry, and nested-PCR, using primers from the Nc5 region of the genomic DNA (PCR PLUS) and primers from the ITS1 region of the ribosomal DNA (PCR JB). A total of 105 fetal samples sent to the Centro de Pesquisa e Desenvolvimento de Sanidade Animal do Instituto Biológico from January 2006 to May 2008 were examined for evidence of N. caninum. Histological examination revealed 71.4% with non-suppurative inflammation in the heart, lung, liver, kidney, placenta, and brain. Immunohistochemistry detected infections in 8.6% of the samples, mainly in the brain, placenta, and heart. Nested-PCR JB revealed 6.7% with infections, while nested-PCR PLUS returned 20.9% positive results, mainly in brain and placenta, and in the pooled liver and heart. Kappa statistics demonstrated little agreement among the three techniques. The three methods are complementary, since they have distinct diagnostic characteristics and were combined to give a positivity rate of 24.8%.
Pesquisou-se Neospora caninum como causador de abortamento e natimortalidade em bovinos, por meio de exame histopatológico (hematoxilina-eosina), imunoistoquímica (IHQ) e nested-PCR, utilizando primers da região Nc5 do DNA genômico (PCR PLUS) e primers da região ITS1 do DNA ribossomal (PCR JB). Foram avaliadas 105 amostras de abortamento bovino entre janeiro de 2006 a maio de 2008, encaminhadas ao Centro de Pesquisa e Desenvolvimento de Sanidade Animal do Instituto Biológico para diagnóstico diferencial de causas infecciosas. Observou-se em 71,4% das amostras lesões histológicas (HE) caracterizadas pela presença de células inflamatórias mononucleares no coração, pulmão, fígado, rim, placenta e cérebro. A IHQ detectou 8,57% de positividade, sendo maior no cérebro, placenta e coração. A nested-PCR JB revelou 6,66% de casos positivos, enquanto que a nested-PCR PLUS apresentou maior taxa de positividade (20,95%), principalmente no cérebro, placenta e no pool fígado/coração. Houve baixo grau de concordância entre as três técnicas pelo índice kappa. A taxa de positividade para qualquer uma das técnicas (IHQ, nested-PCR PLUS e nested-PCR JB) foi de 24,8%, devendo ser consideradas conjuntamente pelo fato de possuírem características distintas e serem, portanto, complementares no diagnóstico definitivo da neosporose.