RESUMEN
In this communication, we report the presence of RNA of bovine viral diarrhea virus (BVDV) as a contaminant of different biological products used in Mexico for veterinary vaccine production. For this purpose, six batches of monovalent vaccines, eight cell line batches used for vaccine production, and 10 fetal bovine serum lots (FBS) commercially available in Mexico from different suppliers were tested by reverse transcription polymerase chain reaction (RT-PCR). Viral RNA was detected in 62.5% of the samples analyzed. Phylogenetic analysis revealed the presence of the subgenotypes BVDV-1a, 1b, and BVDV-2a in the tested samples. Collectively, these findings indicate that contamination by BVDV RNA occurs in commercial vaccines and reagents used in research and production of biological products. The ramifications of this contamination are discussed.
Asunto(s)
Virus de la Diarrea Viral Bovina Tipo 1/genética , Virus de la Diarrea Viral Bovina Tipo 2/genética , Vacunas Virales/genética , Animales , Diarrea Mucosa Bovina Viral/inmunología , Bovinos , Línea Celular , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Genotipo , Síndrome Hemorrágico de los Bovinos/microbiología , México , Filogenia , ARN Viral/genética , Vacunas Virales/inmunologíaRESUMEN
Interferon lambda (IFN-λ) plays an important role in inducing an antiviral state in mucosal surfaces and has been used as an effective biotherapeutic against several viral diseases. Here we performed a proof of concept study on the activity of a biologically active recombinant bovine IFN-λ (rIFN-λ) produced in eukaryotic cells against Bovine Viral Diarrhea Virus (BVDV) in cattle. We first confirmed the lack of toxicity of different concentrations of rIFN-λ in bovine peripheral blood cells and the safety of its subcutaneous application in calves in doses up to 12 IU/kg. The antiviral activity of the rIFN-λ against BVDV was assessed in calves that were inoculated with 6 IU/kg of rIFN-λ (n = 4) or mock-treated (n = 2) two days before and after challenge with a BVDV type-2 non-cytopathic strain. Mock-treated animals developed respiratory disease, shedded the virus from 4 to 7 days post-infection (dpi) and had viremia between 4 and 14 dpi. Conversely, calves treated with rIFN-λ did not develop clinical symptoms. The virus was not found in nasal secretions or sera. Only one animal had a positive viral RNA detection in serum at 7 dpi. All infected animals treated with rIFN-λ increased systemic type-I IFNs levels at 4 dpi. The antiviral treatment induced an earlier onset of the anti-BVDV neutralizing antibodies. Altogether, these results constitute the proof-of-principle of bovine IFN-λ as an antiviral biotherapeutic to protect cattle against the clinical disease caused by BVDV.
Asunto(s)
Diarrea Mucosa Bovina Viral/inmunología , Diarrea Mucosa Bovina Viral/prevención & control , Enfermedades de los Bovinos/prevención & control , Virus de la Diarrea Viral Bovina/inmunología , Diarrea/veterinaria , Inmunización Pasiva , Interferones/administración & dosificación , Factores de Edad , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/virología , Diarrea/prevención & control , Diarrea/virología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Femenino , Inmunización Pasiva/veterinaria , Interferones/clasificación , Interferones/genética , Interferones/inmunología , Prueba de Estudio Conceptual , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/inmunología , Esparcimiento de VirusRESUMEN
The aim of this study was to evaluate secondary clinical disease, milk production efficiency and reproductive performance of heifers and cows persistently infected (PI) with bovine viral diarrhea virus type 2 (BVDV type 2). PI animals (n = 25) were identified using an antigen capture ELISA of ear notch samples. They were distributed into three age groups: ≤ 12 (n = 8), 13 to 24 (n = 6) and 25 to 34 (n = 11) months old. A control group of BVDV antigen ELISA negative female cattle that were age matched to the PI animals was utilized from the same herd. The PI group had a 1.29 higher odds ratio for diarrhea than controls (p = 0.001, IC95% = 1.032-1.623) and 1.615 greater chance of developing bovine respiratory disease (BRD) (p = 0.012, IC95% = 1.155-2.259). The age at first insemination (p = 0.012) and number of insemination attempts required to establish the first pregnancy (p = 0.016) were both higher for PI than controls. Milk production was higher for control cows than PI cows during most of the sampling periods. Somatic cell counts (SCC) were higher in PI cows than the controls at all sampling points across lactation (p ≤ 0.042). PI cattle had a higher incidence of disease, produced less milk, a higher SCC, and poorer reproductive performance than control cattle in this study.
Asunto(s)
Diarrea Mucosa Bovina Viral/fisiopatología , Virus de la Diarrea Viral Bovina Tipo 2/patogenicidad , Lactancia , Leche/química , Reproducción , Animales , Bovinos , Industria Lechera , Diarrea/veterinaria , Diarrea/virología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Femenino , Embarazo , Vacunas Virales/administración & dosificaciónRESUMEN
This study was designed to evaluate the extent of the protection for bovine viral diarrhea virus type 2 (BVDV-2) infection, afforded by vaccination with a combo inactivated vaccine, which contains bovine viral diarrhea virus type 1 (BVDV-1) and infectious bovine rhinotracheitis virus (IBRV). Five 3-4-month-old calves were intramuscularly vaccinated with a single dose of the combo vaccine and boosted with same dose three weeks after the first vaccination, with five mock immunized calves serving as a control group. Twenty-one days after the second vaccination, all calves were challenged with BVDV-2 SX08 strain by spray into nostril. The unvaccinated animals developed typical clinical signs of high rectal temperature, diarrhoea with erosions and a dramatic drop in leukocyte counts. These signs occured markedly less in all vaccinated animals, the rectal temperature, leukopenia and virarmia of which, were significantly less than the mock immunized calves. It can be concluded that vaccination with the combo inactivated vaccine affords cross-protection against clinical effects of a challenge-infection with BVDV-2 SX08 strain, although it was part protection.(AU)
Este estudo foi desenvolvido para avaliar a extensão da proteção contra a infecção pelo vírus da diarréia viral bovina tipo 2 (BVDV-2) através da vacinação com uma vacina combinada inativada contendo o vírus da diarréia viral bovina tipo 1 (BVDV-1) e vírus da rinotraqueíte de bovinos infecciosos (IBRV). Cinco bezerros com 3 a 4 meses de idade foram vacinados via intramuscular com uma dose única da vacina combinada e reforçados com a mesma dose três semanas após a primeira vacinação, com cinco bezerros imunizados em simulação servindo como grupo controle. Vinte e um dias após a segunda vacinação, todos os bezerros foram desafiados com a cepa BVDV-2 SX08 por spray na narina. Os animais não vacinados desenvolveram sinais clínicos típicos, como alta temperatura retal, diarréia com erosões e queda drástica na contagem de leucócitos. Estes sinais tiveram ocorrência significativamente menor em todos os animais vacinados, cuja temperatura retal, leucopenia e virarmia eram significativamente menores do que os bezerros simulados. É possível concluir que a vacinação com a vacina combinada inativada proporciona proteção cruzada contra os efeitos clínicos de uma infecção provocada pela cepa BVDV-2 SX08, embora tenha sido parcialmente protegida.(AU)
Asunto(s)
Animales , Bovinos , Vacunación , Vacunas Combinadas/análisis , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Protección Cruzada , Vacunas de Productos Inactivados , Recuento de LeucocitosRESUMEN
This study was designed to evaluate the extent of the protection for bovine viral diarrhea virus type 2 (BVDV-2) infection, afforded by vaccination with a combo inactivated vaccine, which contains bovine viral diarrhea virus type 1 (BVDV-1) and infectious bovine rhinotracheitis virus (IBRV). Five 3-4-month-old calves were intramuscularly vaccinated with a single dose of the combo vaccine and boosted with same dose three weeks after the first vaccination, with five mock immunized calves serving as a control group. Twenty-one days after the second vaccination, all calves were challenged with BVDV-2 SX08 strain by spray into nostril. The unvaccinated animals developed typical clinical signs of high rectal temperature, diarrhoea with erosions and a dramatic drop in leukocyte counts. These signs occured markedly less in all vaccinated animals, the rectal temperature, leukopenia and virarmia of which, were significantly less than the mock immunized calves. It can be concluded that vaccination with the combo inactivated vaccine affords cross-protection against clinical effects of a challenge-infection with BVDV-2 SX08 strain, although it was part protection.(AU)
Este estudo foi desenvolvido para avaliar a extensão da proteção contra a infecção pelo vírus da diarréia viral bovina tipo 2 (BVDV-2) através da vacinação com uma vacina combinada inativada contendo o vírus da diarréia viral bovina tipo 1 (BVDV-1) e vírus da rinotraqueíte de bovinos infecciosos (IBRV). Cinco bezerros com 3 a 4 meses de idade foram vacinados via intramuscular com uma dose única da vacina combinada e reforçados com a mesma dose três semanas após a primeira vacinação, com cinco bezerros imunizados em simulação servindo como grupo controle. Vinte e um dias após a segunda vacinação, todos os bezerros foram desafiados com a cepa BVDV-2 SX08 por spray na narina. Os animais não vacinados desenvolveram sinais clínicos típicos, como alta temperatura retal, diarréia com erosões e queda drástica na contagem de leucócitos. Estes sinais tiveram ocorrência significativamente menor em todos os animais vacinados, cuja temperatura retal, leucopenia e virarmia eram significativamente menores do que os bezerros simulados. É possível concluir que a vacinação com a vacina combinada inativada proporciona proteção cruzada contra os efeitos clínicos de uma infecção provocada pela cepa BVDV-2 SX08, embora tenha sido parcialmente protegida.(AU)
Asunto(s)
Animales , Bovinos , Vacunación , Vacunas Combinadas/análisis , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Protección Cruzada , Vacunas de Productos Inactivados , Recuento de LeucocitosRESUMEN
Bovine viral diarrhea virus (BVDV, Pestivirus) causes significant economic losses to the livestock industry worldwide. Although serological surveys show that BVDV exposure is widespread in cattle in Uruguay, BVDV-associated diseases are greatly underreported. The aim of this work is to describe the epidemiological, clinical, pathological, and virological findings from spontaneous outbreaks of BVDV-associated diseases in cattle in Uruguay. Diagnostic investigations were performed during 6 spontaneous disease outbreaks on beef and dairy cattle farms in the departments of Colonia, Rio Negro, and Soriano between November 2016 and April 2018. Carcasses of 8 naturally deceased cattle from these outbreaks were necropsied and subjected to histological examination and immunohistochemistry to detect BVDV antigen in the tissues. Reverse transcription real-time PCR and genomic sequencing were also performed to identify BVDV at the species and subtype levels. Other ancillary diagnostic tests, including bacterial cultures, were performed on a case-by-case basis to rule in/out differential diagnoses based on initial clinicopathological presumptive diagnoses. BVDV-associated conditions that were diagnosed in the 8 cases included mucosal disease, transient postnatal BVDV infections associated with digestive/septicemic salmonellosis by Salmonella serovar typhimurium, Histophilus somni bronchopneumonia, urinary tract coinfections with Escherichia coli and Streptococcus sp., enteric coinfection with coccidia, and transplacental fetal infections and abortions with Neospora caninum coinfection. BVDV-1a and BVDV-2b were each identified in four of the eight cases. We conclude that BVDV-1a and BVDV-2b contribute significantly to disease and mortality in cattle in Uruguay. Future research should estimate the economic impact of BVDV in the Uruguayan livestock sector.
Asunto(s)
Diarrea Mucosa Bovina Viral/complicaciones , Enfermedades de los Bovinos/virología , Coinfección , Pestivirus , Animales , Anticuerpos Antiprotozoarios , Anticuerpos Antivirales , Bacterias/aislamiento & purificación , Diarrea Mucosa Bovina Viral/epidemiología , Bronconeumonía/veterinaria , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/parasitología , Coccidios/aislamiento & purificación , Coinfección/microbiología , Coinfección/parasitología , Enfermedades Transmisibles/complicaciones , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/veterinaria , Virus de la Diarrea Viral Bovina Tipo 1/genética , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 1/aislamiento & purificación , Virus de la Diarrea Viral Bovina Tipo 2/genética , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/aislamiento & purificación , Brotes de Enfermedades/veterinaria , Femenino , Inmunohistoquímica , Intestinos/microbiología , Intestinos/parasitología , Intestinos/patología , Intestinos/virología , Pulmón/microbiología , Pulmón/patología , Mortalidad , Neospora/inmunología , Neospora/aislamiento & purificación , Pasteurellaceae/aislamiento & purificación , Pestivirus/genética , Pestivirus/inmunología , Pestivirus/aislamiento & purificación , Pestivirus/patogenicidad , Embarazo , Complicaciones Infecciosas del Embarazo/parasitología , Complicaciones Infecciosas del Embarazo/veterinaria , Salmonella/aislamiento & purificación , Sepsis/veterinaria , Streptococcus/aislamiento & purificación , Sistema Urinario/microbiología , Sistema Urinario/patología , Uruguay/epidemiologíaRESUMEN
Bovine viral diarrhea virus (BVDV) belongs to the genus Pestivirus and can cause reproductive problems in cattle. However, there is still a lack of research to clarify its pathogenicity in different gestational periods of sows and its effects in neonates. In this study, 12 gilts divided into groups (G) were experimentally inoculated with the strain BVDV-2 (SV-253) oronasally at a dose of 106·85 TCID50; one group was inoculated 30 days before insemination (G0; n = 2), three groups were inoculated during gestation (first (G1; n = 2), second (G2; n = 3), third (G3; n = 3)), and a fourth was the control group (G4; n = 2). Samples of blood and nasal swabs from the gilts were collected every three days until delivery for a virus neutralization (VN) test, qRT-PCR, and blood count. On the day of delivery, 40% of the neonates were euthanized to obtain tissue and blood samples at necropsy for histopathology and qRT-PCR. The sows were seroconverted between 12 and 33 days after inoculation, and the virus was detected in the blood between 3 and 12 days and on the nasal swab between 6 and 24 days in the G0, G1, G2 and G3 sows but was not detected in piglet tissues, and no significant alterations were found through histopathology. The mean and standard deviation of the mean cycles (Cq) from blood (Cq = 34.87 ± 0.60) and nasal swab (Cq = 34.61 ± 0.87) samples were between 107 and 490 TCID50/ml. Transient infection was demonstrated with a low viral load, but transplacental infection was not possible in gilts.
Asunto(s)
Diarrea Mucosa Bovina Viral/virología , Virus de la Diarrea Viral Bovina Tipo 2/patogenicidad , Transmisión Vertical de Enfermedad Infecciosa/veterinaria , Placenta/virología , Animales , Anticuerpos Antivirales/sangre , Diarrea Mucosa Bovina Viral/sangre , Diarrea Mucosa Bovina Viral/inmunología , Bovinos , Virus de la Diarrea Viral Bovina Tipo 2/genética , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/aislamiento & purificación , Femenino , Pruebas de Neutralización , Nariz/virología , Embarazo , Seroconversión , Porcinos , VacunaciónRESUMEN
Pestiviruses including Bovine viral diarrhea virus type 1 (BVDV-1), BVDV-2 and Border disease virus (BDV) have been reported in both sheep and cattle populations, together with the HoBi-like, an emerging group of pestiviruses. Pestivirus control programs in the United States have focused on the control of BVDV-1 and 2. The incidence of pestivirus infection in sheep in the United States and the risk of transmission between cattle and sheep populations are unknown. The aim of this study was to perform serological surveillance for pestivirus exposure in sheep from an important sheep producing state in the Unites States, Wyoming. For this, sera from 500 sheep, collected across the state of Wyoming (US) in 2015-2016, were examined by comparative virus neutralization assay against four species/proposed species of pestiviruses: BVDV-1, BVDV-2, BDV and HoBi-like virus. Rates of exposure varied between geographic regions within the state. The overall pestivirus prevalence of antibodies was 5.6%. Antibodies were most frequently detected against BVDV-1 (4%), and the highest antibody titers were also against BVDV-1. Data from this study highlights understanding of the dynamics of sheep pestivirus exposure, consideration of reference strains used for VN assays, transmission patterns, and potential vaccination history should be taken into account in implementation of control measures against pestiviruses in sheep and for successful BVDV control programs in cattle.
Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Pestivirus/veterinaria , Pestivirus/inmunología , Ovinos/inmunología , Animales , Animales Domésticos/inmunología , Animales Domésticos/virología , Bovinos/virología , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/transmisión , Enfermedades de los Bovinos/virología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Virus de la Diarrea Viral Bovina/inmunología , Pruebas de Neutralización , Pestivirus/clasificación , Pestivirus/genética , Infecciones por Pestivirus/epidemiología , Infecciones por Pestivirus/inmunología , Infecciones por Pestivirus/transmisión , Filogenia , Estudios Seroepidemiológicos , Ovinos/virología , Encuestas y Cuestionarios , Wyoming/epidemiologíaRESUMEN
Hobi-like viruses comprise an unclassified group of bovine pestiviruses related to bovine viral diarrhea virus 1 (BVDV-1) and 2 (BVDV-2). These viruses were originally identified in fetal bovine serum from Brazilian origin and, subsequently, isolated from diseased animals in several countries. Herein we performed an antigenic characterization of eight Brazilian HoBi-like viruses isolated from persistently infected (PI) animals and from gastroenteric disease (2007-2015). Phylogenetic analysis based on the 5' unstranslated region (UTR) clustered these viruses with other HoBi-like viruses from European and Asiatic origin. Monoclonal antibody (MAb) binding indicated variability in the Hobi-like virus glycoprotein E2 and significant differences from the homologous BVDV-1 and BVDV-2 glycoprotein. Analysis of antigenic relatedness based on virus-neutralizing titers using virus-specific antisera revealed that HoBi-like viruses are antigenically very different from BVDV-1 and, to a lesser extent, from BVDV-2. Cross-neutralizing assays between pairs of HoBi-like viruses and their respective antisera indicated the existence of antigenic variability among these viruses, even for viruses isolated from the same herd in different occasions. Moreover, the identification of a HoBi-like isolate with low antigenic similarity with the other isolates indicates the potential existence of antigenic subgroups among HoBi-like virus isolates. Finally, sera of lambs immunized with commercial BVDV vaccines showed low or undetectable neutralizing activity against HoBi-like isolates. These results indicate significant antigenic differences between BVDV genotypes and Brazilian HoBi-like viruses and the existence of antigenic variability within this atypical group of pestiviruses. These findings extend the knowledge about the antigenic diversity of HoBi-like viruses and reinforce the need for their inclusion in current BVDV vaccines.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/sangre , Variación Antigénica , Enfermedades de los Bovinos/inmunología , Infecciones por Pestivirus/veterinaria , Pestivirus/inmunología , Animales , Bovinos , Enfermedades de los Bovinos/virología , Virus de la Diarrea Viral Bovina Tipo 1/genética , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 1/aislamiento & purificación , Virus de la Diarrea Viral Bovina Tipo 2/genética , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/aislamiento & purificación , Virus de la Diarrea Viral Bovina/genética , Virus de la Diarrea Viral Bovina/inmunología , Virus de la Diarrea Viral Bovina/aislamiento & purificación , Inmunización/veterinaria , Pestivirus/genética , Pestivirus/aislamiento & purificación , Infecciones por Pestivirus/inmunología , Infecciones por Pestivirus/virología , Filogenia , OvinosRESUMEN
Infection of water buffaloes (Bubalus bubalis) with bovine viral diarrhea viruses (BVDV) has been confirmed in several studies by serological and molecular techniques. In order to determine the presence of persistently infected animals and circulating species and subtypes of BVDV we conducted this study on a buffalo herd, whose habitat was shared with bovine cattle (Bossp.). Our serological results showed a high level of positivity for BVDV-1 and BVDV-2 within the buffalo herd. The molecular analyses of blood samples in serologically negative animals revealed the presence of viral nucleic acid, confirming the existence of persistent infection in the buffaloes. Cloning and sequencing of the 5' UTR of some of these samples revealed the presence of naturally mix-infected buffaloes with at least two different subtypes (1a and 1b), and also with both BVDV species (BVDV-1 and BVDV-2).
Asunto(s)
Búfalos/virología , Portador Sano/veterinaria , Coinfección/virología , Virus de la Diarrea Viral Bovina Tipo 1/aislamiento & purificación , Virus de la Diarrea Viral Bovina Tipo 2/aislamiento & purificación , Infecciones por Pestivirus/veterinaria , Viremia/veterinaria , Regiones no Traducidas 5'/genética , Animales , Anticuerpos Antivirales/sangre , Argentina/epidemiología , Enfermedades Asintomáticas , Diarrea Mucosa Bovina Viral/epidemiología , Diarrea Mucosa Bovina Viral/transmisión , Portador Sano/epidemiología , Portador Sano/virología , Bovinos/microbiología , ADN Viral/genética , Virus de la Diarrea Viral Bovina Tipo 1/clasificación , Virus de la Diarrea Viral Bovina Tipo 1/genética , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/clasificación , Virus de la Diarrea Viral Bovina Tipo 2/genética , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Reservorios de Enfermedades , Reacciones Falso Negativas , Especificidad del Huésped , Infecciones por Pestivirus/epidemiología , Infecciones por Pestivirus/transmisión , Infecciones por Pestivirus/virología , Filogenia , ARN Viral/sangre , Especificidad de la Especie , Viremia/epidemiología , Viremia/virologíaRESUMEN
Este trabalho avaliou a imunogenicidade de vacinas para os herpesvírus bovino 1 e 5 (BoHV-1, BoHV-5) e vírus da diarreia viral bovina 1 e 2 (BVDV-1, BVDV-2), disponíveis no mercado brasileiro. Para isso, novilhos de raças de corte foram alocados em grupos de 10-12 animais e vacinados duas vezes, com intervalo de 30 dias, com cada uma das oito vacinas disponíveis. Amostras de soro coletadas 30 dias após a segunda dose foram submetidas ao teste de virusneutralização (VNT), frente a cepas de BoHV-1, BoHV-5, BVDV-1 e BVDV-2. Com exceção de duas vacinas que induziram soroconversão em 8/10 e 9/10 dos animais, as demais induziram anticorpos neutralizantes contra o BoHV-1 em todos os animais vacinados (títulos médios geométricos [GMTs] entre 1,7 e 4,8). Quatro vacina s induziram anticorpos reagentes com o BoHV-5 em todos os animais (GMTs de 1,0 a 4,2), enquanto três vacinas induziram soroconversão parcial em 5/10, 6/10 e 7/10 animais. Apenas uma vacina induziu resposta sorológica detectável frente ao BVDV-1 em todos os animais vacinados (GMT=6,7). Soroconversão parcial ao BVDV-1 foi detectada em quatro grupos vacinais (6/10, GMT 4,0 6/10, GMT 5,6 e 4/10, GMT 1,8). Uma vacina induziu resposta em apenas um animal (título de 40) e três vacinas não induziram anticorpos detectáveis contra o BVDV-1 em nenhum animal. Atividade neutralizante frente ao BVDV-2 foi detectada apenas em três grupos vacinais, e parcialmente (10/10, GMT 6,5; 5/10, GMT 1,6 e 2/10, GMT 1,0). Cinco vacinas não induziram atividade neutralizante detectável frente ao BVDV-2 em nenhum dos animais imunizados. Esses resultados demonstram que o componente BoHV-1 da maioria das vacinas comerciais possui imunogenicidade adequada. No entanto, o componente BVDV da grande maioria das vacinas não induz resposta neutralizante consistente frente ao BVDV-1 e, ...(AU)
This study evaluated the immunogenicity of vaccines for bovine herpesvirus 1 and 5 (BoHV-1/5) and viral diarrhea virus 1 and 2 (BVDV-1/2) available in the Brazilian market. Calves were divided into groups (10-12), vaccinated twice with a 30 days interval. Samples collected 30 days after the second dose were submitted to virus neutralization test against BoHV-1, BoHV-5, BVDV-1 and BVDV-2. With the exception of two vaccines that induced seroconversion in 8/10 and 9/10 of the animals, the other induced antibodies against BoHV-1 in all vaccinated animals (geometric mean titers [GMTs] 1.7 and 4.8) and four induced antibodies against BoHV-5 in all animals (GMTs 1.0 to 4.2), whereas three vaccines induced partial seroconversion (5/10, 6/10 and 7/10 animals). Only one vaccine induced antibody response to BVDV-1 in all vaccinated animals (GMT=6.7). Partial seroconversion to BVDV-1 was detected in four vaccine (6/10, GMT 4.0; 6/10, GMT 5.6 and 4/10, GMT 1.8). A vaccine induced response in only one animal and three vaccines did not induce antibodies against BVDV-1 in any animal. Antibodies to BVDV-2 were detected only in three vaccine groups, and partly (10/10, GMT 6.5; 5/10, GMT 1.6 and 2/10, GMT 1.0). Five vaccines did not induce antibodies to BVDV-2 in any of the animals. Results demonstrate that the BoHV-1 component of commercial vaccines seems to have acceptable immunogenicity. However, the BVDV component of most vaccines does not induce consistent response against BVDV-1, especially, to BVDV-2. It is evident that strategies for production of vaccines, particularly to BVDV must be urgently revised.(AU)
Asunto(s)
Animales , Masculino , Bovinos , Herpesvirus Bovino 1/inmunología , Herpesvirus Bovino 5/inmunología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Inmunización/veterinaria , VacunasRESUMEN
Llamas and alpacas are domesticated South American camelids (SACs) important to ancestral population in the Altiplano region, and to different communities where they have been introduced worldwide. These ungulates have shown to be susceptible to several livestock viral pathogens such as members of the Pestivirus genus and mainly to bovine viral diarrhea virus (BVDV). Seventeen Chilean BVDV isolates were analyzed by serum cross neutralization with samples obtained from five llama, six alpacas, three bovines, plus three reference strains belonging to different subgroups and genotypes. The objective was to describe antigenic differences and similarities among them. Antigenic comparison showed significant differences between different subgroups. Consequently, antigenic similarities were observed among isolates belonging to the same subgroup and also between isolates from different animal species belonging the same subgroup. Among the analyzed samples, one pair of 1b subgroup isolates showed significant antigenic differences. On the other hand, one pair of isolates from different subgroups (1b and 1j) shared antigenic similarities indicating antigenic relatedness. This study shows for the first time the presence of antigenic differences within BVDV 1b subgroup and antigenic similarities within 1j subgroup isolates, demonstrating that genetic differences within BVDV subgroups do not necessary corresponds to differences on antigenicity.
Asunto(s)
Variación Antigénica , Diarrea Mucosa Bovina Viral/virología , Camélidos del Nuevo Mundo/virología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Animales , Antígenos Virales/inmunología , Bovinos/virología , Chile , Diarrea/veterinaria , Diarrea/virología , Virus de la Diarrea Viral Bovina Tipo 1/genética , Virus de la Diarrea Viral Bovina Tipo 1/aislamiento & purificación , Virus de la Diarrea Viral Bovina Tipo 2/genética , Virus de la Diarrea Viral Bovina Tipo 2/aislamiento & purificación , Genotipo , Pruebas de NeutralizaciónRESUMEN
HoBi-like viruses are an emerging species of pestiviruses with genetic and antigenic similarities to bovine viral diarrhea viruses 1 and 2 (BVDV1 and BVDV2). Vaccines for HoBi-like viruses are not yet available. However, both modified live virus (MLV) and killed virus (KV) vaccines against BVDV are widely used worldwide. This study evaluated the cross reactive antibody response against HoBi-like pestiviruses in sera of cattle immunized with BVDV1 and BVDV2 vaccines. Groups "KV" and "MLV", with 25 calves each, received killed or modified live vaccines, respectively, containing both BVDV1 and BVDV2 antigens. The antibody response was evaluated by virus neutralization test. The average of geometric mean titers (GMTs) of neutralizing antibodies in serum against HoBi-like viruses in the MLV group was 12.9, whereas GMTs to BVDV1, BVDV2 and border disease virus (BDV) were 51.1, 23.5, and 12.4, respectively. In this group, neutralizing antibodies against BVDV1, BVDV2, HoBi-like viruses and BDV were detected in 100%, 94%, 68% and 68% of calves, respectively. The GMT of neutralizing antibodies in serum against BVDV1, BVDV2, HoBi-like viruses and BDV in the KV group were 24.7, 14.5, 10.4 and 11, respectively. Similarly, the percentage of animals with neutralizing antibodies against BVDV1, BVDV2, HoBi-like viruses and BDV were 84%, 56%, 34% and 44%, respectively. These results indicate that MLV or killed BVDV1 and BVDV2 vaccines induce a cross reactive antibody response comparatively weak to HoBi-like viruses, and this response would likely not suffice to confer protection.
Asunto(s)
Anticuerpos Antivirales/inmunología , Bovinos/inmunología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Pestivirus/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Virus de la Diarrea Viral Bovina Tipo 1/genética , Virus de la Diarrea Viral Bovina Tipo 2/genética , Inmunización , Pruebas de Neutralización/veterinaria , Pestivirus/genética , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/genética , Vacunas de Productos Inactivados/inmunología , Vacunas Virales/administración & dosificación , Vacunas Virales/genéticaRESUMEN
The emergence of a newly recognized group of pestiviruses in cattle, the HoBi-like viruses, requires an evaluation of the available diagnostic tools and vaccines. The present study compared antigenic characteristics of Bovine viral diarrhea virus 1 and 2 (BVDV-1, -2) strains and HoBi virus. This comparison was based on detection of HoBi virus and antibodies against it by commercial enzyme-linked immunosorbent assays (ELISAs) and the level of cross-neutralizing antibodies present in sera from animals vaccinated with BVDV. Reactivity with a panel of monoclonal antibodies (mAbs) revealed greater cross-reactivity between BVDV species (BVDV-1, -2) and HoBi epitopes within E(rns) and NS2/3 proteins than between epitopes located in the E2 glycoprotein. The results suggest that a diagnostic test designed to detect both BVDV species and HoBi could be based on E(rns) or NS2/3 epitopes, while variation among E2 epitopes could be exploited in tests for differentiation of pestivirus species. The threshold of detection of HoBi virus by an antigen-capture ELISA kit based on detection of E(rns) was statistically similar to that for BVDV. In contrast, 2 commercial ELISA kits designed to detect antibodies against BVDV missed 22.2% and 77.7%, respectively, of serum samples harboring HoBi virus-neutralizing antibodies. In addition, sera of calves vaccinated with BVDV-1 and -2 presented low neutralizing activity against HoBi virus. The results demonstrate that in spite of antigenic similarities, HoBi virus is antigenically distinct from both BVDV species. Detection and control of HoBi virus infections in cattle would thus require the development of new diagnostic reagents and reformulation of current vaccines.
Asunto(s)
Diarrea Mucosa Bovina Viral/inmunología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Animales , Anticuerpos Monoclonales/inmunología , Variación Antigénica , Diarrea Mucosa Bovina Viral/diagnóstico , Diarrea Mucosa Bovina Viral/virología , Bovinos , Virus de la Diarrea Viral Bovina Tipo 1/aislamiento & purificación , Virus de la Diarrea Viral Bovina Tipo 2/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/métodosRESUMEN
The objectives of this cross-sectional study were to estimate the seroprevalence of infectious bovine rhinotracheitis (IBR, BHV-1) and bovine viral diarrhea virus (BVDV) in a population of non-vaccinated, double purpose, dairy and beef herds in the Pacific Region of Central Costa Rica. Blood samples were collected from a total of 496 animals from 35 herds. Sera were tested for antibodies against BHV-1(IBR) and BVDV types 1 and 2 using serum neutralization test. The average number of animals tested in each herd for each of the viruses was 14. Overall individual seroprevalence was 48%, 27%, and 19% for IBR, BVDV type 1, and BVDV type 2, respectively. Median within-herd seroprevalence for IBR, BVDV type 1 and type 2 were 43%, 27%, and 24%, respectively.
Asunto(s)
Anticuerpos Antivirales/sangre , Diarrea Mucosa Bovina Viral/epidemiología , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/epidemiología , Animales , Diarrea Mucosa Bovina Viral/inmunología , Diarrea Mucosa Bovina Viral/virología , Bovinos , Costa Rica/epidemiología , Estudios Transversales , Femenino , Rinotraqueítis Infecciosa Bovina/inmunología , Rinotraqueítis Infecciosa Bovina/virología , Masculino , Prevalencia , Estudios Seroepidemiológicos , VacunaciónRESUMEN
The occurrence of neutralizing antibodies against bovine viral diarrhea virus genotypes (BVDV-1 and BVDV-2) has been confirmed by virus neutralization test (VN) in samples of blood serum from 26 cattle herds which were not BVDV vaccinated, located in the states of Minas Gerais and São Paulo, Brazil. Ten blood samples were collected from each herd, five samples from 6 to 12-month-old calves and five samples from adult bovines. Of the total samples analyzed, 102 (39.2%) were reactive to BVDV, more specifically, 81 (31.1%) were reactive to BVDV-1 and BVDV-2, seven (2.7%) were reactive to BVDV-1 only and 14 (5.4%) were reactive to BVDV-2 only. Except for two herds, in all others at least one animal was detected reactive to BVDV, however, one of them was reactive to BVDV-2 only. In six herds, neutralizing antibodies were detected in blood serum from 6 to 12-month-old calves. Therefore, were indicative of recent BVDV infection and also suggested the likely presence of an infection source in the herd. The results showed the occurrence of neutralizing antibodies against BVDV genotypes in cattle herds located in the states analyzed, but these same results demonstrated the differences in the number of bovines reactive for BVDV-1 and BVDV-2, thus demonstrating the need to use strains from each genotype in VN tests for serological diagnosis of BVDV.
A ocorrência de anticorpos neutralizantes contra os genótipos do vírus da diarréia viral bovina (BVDV-1 e BVDV-2) foi determinada pelo teste de virusneutralização (VN) em amostras de soro sangüíneo provenientes de 26 rebanhos bovinos não vacinados contra o BVDV, localizados nos Estados de Minas Gerais e São Paulo, Brasil. Foram analisadas 10 amostras por rebanho, sendo cinco de bovinos adultos e cinco de bovinos com idade entre 6 e 12 meses. Do total de 260 amostras analisadas, 102 (39,2%) reagiram ao BVDV, das quais 81 (31,1%) foram reagentes tanto ao BVDV-1 quanto ao BVDV-2, sete (2,7%) reagiram apenas ao BVDV-1 e 14 (5,4%) reagiram apenas ao BVDV-2. Com exceção de dois rebanhos, nos demais foram detectados pelo menos um animal reagente ao BVDV, entretanto, foram detectados animais reagentes apenas ao BVDV-2 em um deles. Em seis rebanhos foram detectados anticorpos neutralizantes nos bovinos da faixa etária de 6 a 12 meses, sendo, portanto, indicativos da infecção recente pelo vírus e também sugestivos da provável presença da fonte de infecção no rebanho. Os dados obtidos mostraram a ocorrência de anticorpos neutralizantes contra os genótipos do BVDV em rebanhos bovinos localizados nos Estados analisados, mas os resultados apresentaram diferenças no número de bovinos reagentes ao BVDV-1 e ao BVDV-2, ressaltando assim a necessidade da utilização de estirpes de cada genótipo nos testes de VN para o diagnóstico sorológico do BVDV.
Asunto(s)
Animales , Bovinos , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Anticuerpos Neutralizantes , Pruebas de Neutralización/veterinariaRESUMEN
The reproduction effects of bovine viral diarrhea virus type-2 (BVDV-2) infection were investigated in ewes inoculated with a non-cytopathic BVDV-2 isolate at three stages of gestation. Virus inoculation was followed by a transient viremia, accompanied by a transient and mild hyperthermia and nasal discharge in a few animals. Some ewes were sacrificed at different time-points after virus inoculation to study the kinetics of fetal infection. Infectivity and viral antigens were detected in placentomes from day 7 to 36 post-inoculation (pi) and in fetal fluids and tissues between days 10 and 28 pi. Cardiac petechial hemorrhages and hemoperitoneum accompanied by a severe fibrinous ulcerative placentitis were observed in fetuses examined at days 21, 28 and 36 pi. Inoculation of ewes at days 55-60 of gestation resulted in a prolonged virus replication in placentomes and fetal tissues; ewes that were allowed to proceed with pregnancy had 77% of abortions or fetal and perinatal deaths. Seven stillbirths, unviable and viable lambs born to these ewes were virus-positive at birth. Infectious virus was repeatedly isolated from leukocytes of two lambs up to 2 and 6 months of age, indicating they were persistently infected. Ewes inoculated at days 65-70 of gestation had 66.6% of fetal and perinatal losses. Three viable lambs born to these ewes were healthy, BVDV antibody-positive and virus-negative. A transient viral replication in placentomes and in a few fetal tissues, followed by the rise of fetal neutralizing antibodies and virus clearance was the result of inoculating ewes at days 120-125 of gestation. Lambs born to these ewes were healthy, antibody-positive and virus-negative. These results demonstrate that the biology of BVDV-2 infection in pregnant sheep is essentially similar to that of BVDV-1 in pregnant cattle and sheep. These features make this species an attractive animal model for studying the pathogenesis of congenital BVDV-2 infection.
Asunto(s)
Diarrea Mucosa Bovina Viral/patología , Virus de la Diarrea Viral Bovina Tipo 2/crecimiento & desarrollo , Complicaciones Infecciosas del Embarazo/veterinaria , Enfermedades de las Ovejas/virología , Animales , Anticuerpos Antivirales/sangre , Antígenos Virales/análisis , Diarrea Mucosa Bovina Viral/sangre , Diarrea Mucosa Bovina Viral/virología , Brasil , Bovinos , Corteza Cerebral/embriología , Corteza Cerebral/patología , Corteza Cerebral/virología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Femenino , Sangre Fetal/virología , Muerte Fetal/virología , Inmunohistoquímica , Masculino , Placenta/patología , Placenta/virología , Embarazo , Complicaciones Infecciosas del Embarazo/sangre , Complicaciones Infecciosas del Embarazo/virología , Resultado del Embarazo/veterinaria , Distribución Aleatoria , Ovinos , Enfermedades de las Ovejas/patologíaRESUMEN
Nucleotide sequencing and phylogenetic analysis of Brazilian bovine viral diarrhea virus (BVDV) field isolates identified four viruses belonging to the genotype 2. Comparison of 5' UTR sequences from these isolates to those of North American BVDV type 2 revealed genomic variations that correlated with the geographic origins of the isolates. Two of the Brazilian type 2 viruses were isolated from clinical cases of gastroenteric/respiratory disease and two were isolated from healthy bovine fetuses. The clinical cases affected young animals (8- and 18-months-old) and were characterized by diarrhea, respiratory signs, extensive oral and digestive tract erosions, conjunctival and vulvar congestion, occasional digestive bleeding and vulvar and heart petechial hemorrhage. Antigenic analysis of these isolates with a panel of 10 monoclonal antibodies revealed marked antigenic differences in the major envelope glycoprotein, gp53/E2, compared to standard laboratory and vaccine BVDV strains. In addition, virus-specific antisera raised to Brazilian BVDV type 2 viruses displayed very low serological cross-reactivity with standard BVDV type 1 strains. Differences up to 64-fold in cross-neutralization titers were observed between BVDV type 1 and Brazilian BVDV type 2 isolates. The identification of BVDV type 2 among Brazilian cattle may have important implications for epidemiological studies, diagnostic and immunization strategies. Furthermore, the low neutralizing activity of BVDV type 1 antisera against the recently identified Brazilian BVDV type 2 isolates raises the question about the degree of protection conferred by BVDV vaccines, most of them based on a single type 1 strain.