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1.
Arch Virol ; 163(6): 1549-1557, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29468362

RESUMEN

Bovine herpesvirus type 1 (BoHV-1) is recognized as an important pathogen causing respiratory, reproductive, and neurological disorders in cattle and is associated with economic losses to animal industry. Accurate diagnostic methods are needed for prevention of disease transmission. While the virus neutralization test is considered the gold standard method, it requires maintenance of the virus and cell cultures, which is time consuming and expensive. Serological techniques such as enzyme-linked immunosorbent assay (ELISA) are widely applied, as these are easy to perform and provide quick results. In the present study, a nanogold slot blot inhibition assay was developed for the serological diagnosis of BoHV-1 and compared with standard ELISA and horseradish peroxidase (HRP) slot blot assays. Of 42 serum samples tested by ELISA, 32 (76.2%) were positive and 10 (23.8%), were negative. The sensitivity and specificity of the nanogold slot blot inhibition assay was similar to that observed for ELISA and HRP slot blot assays, and a strong correlation was observed between the tests. Thus, the nanogold slot blot inhibition assay may serve as an efficient and rapid alternative to ELISA in settings, where plate-reading equipment is lacking.


Asunto(s)
Anticuerpos Antivirales/química , Bioensayo , Western Blotting/métodos , Oro Coloide/química , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/diagnóstico , Animales , Anticuerpos Antivirales/aislamiento & purificación , Benchmarking , Western Blotting/instrumentación , Bovinos , Perros , Ensayo de Inmunoadsorción Enzimática , Herpesvirus Bovino 1/aislamiento & purificación , Sueros Inmunes/química , Inmunoconjugados/química , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/virología , Células de Riñón Canino Madin Darby , Nanopartículas del Metal/química , Sensibilidad y Especificidad
2.
Protein Expr Purif ; 130: 21-27, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27693624

RESUMEN

Bovine herpesvirus (BoHV) glycoprotein E (gE) is a non-essential envelope glycoprotein and the deletion of gE has been used to develop BoHV-1 and BoHV-5 differential vaccine strains. The DIVA (Differentiation of Infected from Vaccinated Animals) strategy, using marker vaccines based on gE-negative BoHV strains, allows the identification of vaccinated or infected animals in immunoassays designed to detect anti-gE antibodies. In this study a codon optimized synthetic sequence of gE containing highly conserved regions from BoHV-1 and BoHV-5 was expressed in Pichia pastoris. Following expression, the recombinant gE (rgE) was secreted and purified from the culture medium. The rgE was identified by Western blotting (WB) using sera from cattle naturally infected with BoHV-1 and/or BoHV-5, or sera from bovines experimentally infected with wild-type BoHV-5. Sera collected from cattle vaccinated with a BoHV-5 gI/gE/US9¯ marker vaccine failed to recognise rgE. Expression of rgE, based on a sequence containing highly conserved regions from BoHV-1 and BoHV-5, in P. pastoris enabled the production of large quantities of rgE suitable for use in immunoassays for the differentiation vaccinated or infected cattle.


Asunto(s)
Expresión Génica , Herpesvirus Bovino 1/genética , Herpesvirus Bovino 5 , Rinotraqueítis Infecciosa Bovina , Pichia/metabolismo , Proteínas del Envoltorio Viral , Proteínas Virales , Animales , Bovinos , Herpesvirus Bovino 1/metabolismo , Vacunas contra Herpesvirus/farmacología , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/diagnóstico , Pichia/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/aislamiento & purificación , Proteínas del Envoltorio Viral/metabolismo , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/aislamiento & purificación , Proteínas Virales/metabolismo
3.
Trop Anim Health Prod ; 42(6): 1041-2, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20143159

RESUMEN

Bovine herpesvirus-1 (BoHV-1) causes a variety of disease syndromes including, respiratory, nervous and reproductive disorders both in domestic as well as wild bovines and the disease is prevalent throughout the world including India. In this study, serum samples of yaks were screened for serological evidence of BoHV-1 in a yak farm with history of abortion and kerato-conjuctivitis by competition-ELISA. The result of seroprevalence of BoHV-1 infections in yaks (Poephagus grunniens) revealed that the overall seroprevalence was 60.1%. The sero-prevalence of BoHV-1 infections was highest in male calf (67.7%) followed by yak cows (62.6%), yak bulls (56.8%), and yak heifers (50.0%).


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/virología , Bovinos , Herpesvirus Bovino 1 , Rinotraqueítis Infecciosa Bovina/epidemiología , Factores de Edad , Animales , Enfermedades de los Bovinos/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , India/epidemiología , Rinotraqueítis Infecciosa Bovina/sangre , Masculino , Estudios Seroepidemiológicos , Factores Sexuales
4.
Vet Ital ; 56(4): 257-262, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33635614

RESUMEN

Camels (Camelus dromedarius) are bred in Western Turkey, particularly in the province of Aydin, for touristic, social and cultural purposes. Bovine enterovirus­1 (BEV­1), Bovine herpesvirus type­1 (BHV­1), Bovine viral diarrhea virus (BVDV), and Parainfluenza­3 (PI­3) virus infections are significant causes of health and/or economic concerns in several animal species. These agents have not been investigated in the camel population in Turkey. The objective of this study was to serologically investigate the presence and infection rates of these viruses in camels in Aydin province, Western Turkey. Ninety­two serum samples were taken from clinically healthy camels that were kept in private farms or brought to the local slaughterhouses. Serum neutralization test was performed to assess the presence and the titers of specific antibodies against BEV­1, BHV­1, BVDV, and PI­3 virus in camel sera. Of the 92 camels tested, 30 (32.61%), 2 (2.17%), 54 (58.7%), and 20 (21.74%) were seropositive for BEV­1, BHV­1, BVDV, and PI­3, respectively. These results suggest that, except for BHV­1, these viral infections are common among camels in Western Turkey. To our knowledge, this the first comprehensive, large­scale study investigating these viral infections in camels in Turkey.


Asunto(s)
Diarrea Mucosa Bovina Viral/epidemiología , Camelus , Infecciones por Enterovirus/epidemiología , Rinotraqueítis Infecciosa Bovina/epidemiología , Animales , Diarrea Mucosa Bovina Viral/sangre , Diarrea Mucosa Bovina Viral/virología , Bovinos , Virus de la Diarrea Viral Bovina/aislamiento & purificación , Infecciones por Enterovirus/sangre , Infecciones por Enterovirus/virología , Enterovirus Bovino/aislamiento & purificación , Femenino , Herpesvirus Bovino 1/aislamiento & purificación , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/virología , Masculino , Turquía/epidemiología
5.
New Microbiol ; 32(2): 135-41, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19579689

RESUMEN

Infectious bovine rhinotracheitis (IBR) virus was grown in Madin Darby bovine kidney (MDBK) cell line using a roller culture system for its large-scale production. Optimum multiplicity of infection (MOI) of 1:750 was found to give consistent virus yield. To determine the appropriate payload, three batches of antigen with virus titres ranging from 10(8.37) to 10(6.37) TCID50 per ml were used to prepare experimental inactivated IBR oil adjuvant vaccine. Beta-propiolactone (BPL) was used as inactivant. The vaccine formulation using inactivated BHV-1 virus antigen with a pre-inactivation titer of 10(8.37) TCID50 per dose elicited better sero-conversion in cattle calves as evidenced from the mean log SN titre of 1.02. To choose the appropriate adjuvant, two batches of vaccine each containing aluminum hydroxide gel (Algel) and Montanide oil respectively were tested in calves. Two groups of 16 calves each were inoculated with Algel and oil adjuvant vaccine respectively twice at four weeks to test the immunogenicity. Adequate titres of vaccine induced anti BHV-1 antibodies could be demonstrated both by ELISA and MNT up to 180 days post vaccination in both the groups.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Hidróxido de Aluminio/uso terapéutico , Vacunas contra Herpesvirus/administración & dosificación , Rinotraqueítis Infecciosa Bovina/inmunología , Rinotraqueítis Infecciosa Bovina/prevención & control , Manitol/análogos & derivados , Ácidos Oléicos/uso terapéutico , Vacunas de Productos Inactivados/administración & dosificación , Animales , Anticuerpos Antivirales/sangre , Antígenos Virales/inmunología , Bovinos , Técnicas de Cultivo de Célula , Línea Celular , Herpesvirus Bovino 1/inmunología , Vacunas contra Herpesvirus/síntesis química , Rinotraqueítis Infecciosa Bovina/sangre , Manitol/uso terapéutico , Pruebas de Neutralización , Vacunación/métodos , Vacunas de Productos Inactivados/síntesis química
6.
Prev Vet Med ; 171: 104743, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31476591

RESUMEN

Within the framework of the national voluntary eradication program for Bovine alphaherpesvirus 1 (BoHV1) in France, the proportion of certified-free herds which experienced no more than two positive animals (termed singleton reactors) steadily increased to reach up to 95% in 2015. The aim of this study was to collate and evaluate serological data to gain insight into these epidemiological questionable BoHV1 seropositive animals. Preliminary evaluation of the performances of BoHV1 ELISA kits using a collection of 997 field sera with well-defined status revealed a relatively low specificity of the two gB blocking ELISAs most used in France for confirmatory testing (93.2% and 97.5% for gB-IDVet and gB-Idexx, respectively). In both ELISAs, the suboptimal specificity was associated with the presence of antibodies against BoHV2. Reassessment of the cut-offs led to a specificity and a sensitivity higher than 99.3%. Consequently, a comprehensive analysis of gB-positive sera from 2551 singleton reactors was performed by using gB ELISAs with optimized cut-offs, combined with viral neutralization test (campaign 2014-2015) or gE ELISA (campaign 2015-2016). Fifty percent of the 728 sera collected in 2014-2015 reacted below the optimized cut-offs in both gB ELISAs. Analysis of new blood samples collected at a minimum 6-week interval showed that these weak-positive reactions did not increase with time and could not be confirmed by confirmatory tests. Among the 1823 sera collected in 2015-2016, only 84 samples tested positive by gE ELISA, most of them corresponding to sera with reactivity above the optimized cut-offs in gB ELISAs. Screening for BoHV2 antibodies revealed a significantly increased prevalence among herds with singleton reactors, compared with the between-herd prevalence in French cattle herds. Altogether, these results provided suitable analytical strategies to limit the occurrence of false-positive BoHV1 reactions and inappropriate withdrawal of the BoHV1-free status, without alteration of diagnostic costs and reliability of eradication programs.


Asunto(s)
Anticuerpos Antivirales/sangre , Herpesvirus Bovino 1/aislamiento & purificación , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/epidemiología , Animales , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Francia/epidemiología , Rinotraqueítis Infecciosa Bovina/prevención & control , Vigilancia en Salud Pública/métodos , Curva ROC , Sensibilidad y Especificidad
7.
Prev Vet Med ; 169: 104705, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31311643

RESUMEN

A cross-sectional study was carried out to estimate the animal- and herd-level prevalence of bovine herpesvirus 1 (BoHV-1) infection in cattle in the State of Paraíba, and to identify risk factors associated with herd-level infection. The state was divided into three sampling strata, and for each stratum, the prevalence of herds infected with BoHV-1 was estimated through a two-stage sampling survey carried out from September 2012 to January 2013. In total, 2443 animals were sampled from 478 herds. A virus-neutralization test was used for BoHV-1 antibody detection. A Bayesian latent-class model was used to describe the data, taking into account imperfect diagnostic test characteristics and the non-independence of test results from animals within the same herd, and using a dynamic within-model risk factor selection method based on indicator variable selection. The adjusted herd-level prevalence was estimated to be 84% (95% CI: 80-88%) for the State of Paraíba, and the animal-level prevalence was estimated to be 73% (95% CI: 66-84%). Only five of the available risk factors were used by the model, with the three most influential being disposal of aborted foetuses (3.78, 95% CI: 1.11-13.85), sharing resources with other farms (3.0, 95% CI: 1.1-8,6), and a herd size of > 23 animals (2.5, 95% CI: 1.1-6.0). Our findings suggest that the animal- and herd-level seroprevalence of BoHV-1 infection in the State of Paraíba is high. While some risk factors such as herd size and sharing resources were identified as risk factors for BoHV-1 infection, these risk factors are initially likely to be of only minor relevance in a control programme due to the extremely high prevalence of infected farms. However, the results are relevant to the risk of reintroduction of disease on farms that have previously eradicated the disease.


Asunto(s)
Rinotraqueítis Infecciosa Bovina/epidemiología , Crianza de Animales Domésticos , Animales , Anticuerpos Antivirales , Brasil/epidemiología , Bovinos , Estudios Transversales , Herpesvirus Bovino 1/aislamiento & purificación , Rinotraqueítis Infecciosa Bovina/sangre , Modelos Logísticos , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos
8.
Vet Microbiol ; 127(1-2): 136-41, 2008 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-17889456

RESUMEN

To understand the nationwide seroprevalence of bovine herpesvirus type 1 (BoHV-1) infection of cows in China, 1344 sera of dairy cows from 29 provinces and 765 sera from 6 herds in Hubei province were collected with stratified random sampling. Another 483 sera from imported cows were included. The serum antibody was tested by BoHV-1 gG ELISA. The results demonstrated that the overall nationwide seroprevalence was 35.8% (481/1344), while the prevalence for individual province ranged from 12.1% to 77.8%. Although each province had positive samples, the prevalence was clustered in areas based on the cow population size. In Hubei Province, the overall seroprevalence was 22.2% (170/765) while the prevalence for individual farms varied greatly from 0.0% to 41.5%. The sera from imported cows had a moderate prevalence of 21.7% (105/483).


Asunto(s)
Anticuerpos Antivirales/sangre , Herpesvirus Bovino 1/fisiología , Rinotraqueítis Infecciosa Bovina/epidemiología , Animales , Bovinos , China/epidemiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/virología , Estudios Seroepidemiológicos
9.
Vopr Virusol ; 51(4): 45-8, 2006.
Artículo en Ruso | MEDLINE | ID: mdl-16929599
10.
Biosens Bioelectron ; 79: 669-78, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26765531

RESUMEN

Quantitative point-of-care (POC) devices are the next generation for serological disease diagnosis. Whilst pathogen serology is typically performed by centralized laboratories using Enzyme-Linked ImmunoSorbent Assay (ELISA), faster on-site diagnosis would infer improved disease management and treatment decisions. Using the model pathogen Bovine Herpes Virus-1 (BHV-1) this study employs an extended-gate field-effect transistor (FET) for direct potentiometric serological diagnosis. BHV-1 is a major viral pathogen of Bovine Respiratory Disease (BRD), the leading cause of economic loss ($2 billion annually in the US only) to the cattle and dairy industry. To demonstrate the sensor capabilities as a diagnostic tool, BHV-1 viral protein gE was expressed and immobilized on the sensor surface to serve as a capture antigen for a BHV-1-specific antibody (anti-gE), produced in cattle in response to viral infection. The gE-coated immunosensor was shown to be highly sensitive and selective to anti-gE present in commercially available anti-BHV-1 antiserum and in real serum samples from cattle with results being in excellent agreement with Surface Plasmon Resonance (SPR) and ELISA. The FET sensor is significantly faster than ELISA (<10 min), a crucial factor for successful disease intervention. This sensor technology is versatile, amenable to multiplexing, easily integrated to POC devices, and has the potential to impact a wide range of human and animal diseases.


Asunto(s)
Técnicas Biosensibles/instrumentación , Herpesvirus Bovino 1/aislamiento & purificación , Rinotraqueítis Infecciosa Bovina/diagnóstico , Sistemas de Atención de Punto , Potenciometría/instrumentación , Animales , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/sangre , Técnicas Biosensibles/economía , Bovinos , Diseño de Equipo , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/virología , Humanos , Proteínas Inmovilizadas/química , Inmunoensayo/economía , Inmunoensayo/instrumentación , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/virología , Sistemas de Atención de Punto/economía , Potenciometría/economía , Pruebas Serológicas/economía , Pruebas Serológicas/instrumentación , Factores de Tiempo , Proteínas Virales/química
11.
Arch Immunol Ther Exp (Warsz) ; 41(3-4): 193-7, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8129561

RESUMEN

Fifty-six calves, seronegative for infectious bovine rhinotracheitis (IBR) virus, were randomly divided into 7 equal groups (n = 8) and given 0.0, 0.05, 0.50, or 5.00 international units (IU) of natural or recombinant human interferon alpha per kg body weight (nHuIFN-alpha or rHuIFN-alpha, respectively) orally once daily for 4 consecutive days, starting 2 days before intranasal inoculation with virulent IBR virus. Calves given 0.05 IU nHuIFN-alpha/kg bwt had significantly greater weight gain at days 15 (P < 0.10) and 25 (P < 0.05) than the placebo-treated (0.0 IU) control group. The treatment groups given 0.05 and 0.5 IU nHuIFN-alpha/kg bwt nHuIFN-alpha had fewer days with temperature > 40 degrees C (P < 0.05 and P = 0.10, respectively), and lower mean rectal temperatures on days 8 and 11 (0.05 IU/kg bwt; P < 0.10) or on day 11 (0.5 IU/kg bwt; P < 0.10). None of the calves given 0.05 IU nHuIFN-alpha/kg bwt required antibiotic therapy. Calves given 0.50 IU/kg bwt of nHuIFN-alpha, or 0.05 IU/kg bwt of rHuIFN-alpha had fewer (P < 0.05) total days of antibiotic therapy compared to controls. These data indicate that low dose oral IFN-alpha treatment significantly reduced the clinical effects of IBR virus infection in feedlot cattle in an interferon dose-dependent fashion.


Asunto(s)
Rinotraqueítis Infecciosa Bovina/terapia , Interferón-alfa/uso terapéutico , Administración Oral , Animales , Anticuerpos Antivirales/sangre , Temperatura Corporal/efectos de los fármacos , Bovinos , Ingestión de Alimentos/efectos de los fármacos , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/sangre , Interferón Tipo I/uso terapéutico , Interferón-alfa/metabolismo , Masculino , Proteínas Recombinantes , Aumento de Peso/efectos de los fármacos
12.
Vet Immunol Immunopathol ; 23(1-2): 61-74, 1989 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-2559538

RESUMEN

The in vivo administration of bovine recombinant interleukin-2 (rIL-2) was evaluated in calves vaccinated and then challenged with bovine herpesvirus-1 (BHV-1). In Experiment 1, 24 calves were allotted to four groups: control; bovine rIL-2; BHV-1 vaccine (modified-live); and bovine rIL-2 + BHV-1 vaccine. Serum neutralizing antibody titers to BHV-1 were increased sixfold, and virus shedding was fourfold less in calves vaccinated and treated with rIL-2 (25 micrograms/kg, intramuscularly) when compared to calves that received vaccine only. Treatment with rIL-2 induced lymphokine-activated killer activity that was eliminated by pretreating effector cells with complement and a monoclonal antibody (B26A) specific for the sheep red blood cell receptor. The rIL-2 treatment in BHV-1-vaccinated calves increased the calves' ability to withstand a BHV-1 challenge. However, during treatment with rIL-2, calves developed diarrhea and mild fever that abated after IL-2 treatment was stopped. A second experiment was then conducted to determine a dose of rIL-2 that would enhance immunity to BHV-1 without causing adverse side effects. Twenty-five calves were allotted to five groups that received injections of rIL-2 at 0.0, 25.0, 2.5, 0.25, or 0.025 micrograms kg-1 day-1 for 5 days. All calves received a modified-live BHV-1 vaccine. Calves treated with 25.0 micrograms kg-1 day-1 showed similar adverse side effects as in the first experiment but all other calves were normal. Compared to control calves, those treated with 25.0, 2.5, and 0.25 micrograms kg-1 day-1 of rIL-2 had higher (P less than 0.05) serum antibody titers to BHV-1 and following challenge lower (P less than 0.05) BHV-1 titers in nasal secretions; additionally, clinical disease as evidenced by nasal and ocular discharge was less severe (P less than 0.05). In vitro cytotoxic responses against BHV-1-infected bovine kidney cells were increased (P less than 0.05) in calves treated with rIL-2 in a dose dependent manner. These data suggest that bovine rIL-2 at 2.5 to 0.25 micrograms/kg may be an effective adjuvant to immunization.


Asunto(s)
Rinotraqueítis Infecciosa Bovina/prevención & control , Interleucina-2/farmacología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Antivirales/biosíntesis , Bovinos , Citotoxicidad Inmunológica , Estudios de Evaluación como Asunto , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/inmunología , Interleucina-2/administración & dosificación , Recuento de Leucocitos , Activación de Linfocitos , Vacunas Virales/administración & dosificación
13.
J Vet Diagn Invest ; 9(1): 24-31, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9087921

RESUMEN

Commercial enzyme-linked immunosorbent assays (ELISAs) for detection of serum antibodies to bovine viral diarrhea virus (BVDV), parainfluenza-3 virus (PI3V), respiratory syncytial virus (RSV), and infectious bovine rhinotracheitis virus (IBRV) were standardized to give a quantitative result when testing was performed at a single optimum dilution. For each test, serum samples were titrated and their end point titers calculated by an algebraic method directly from a plot of each titration series and also from a regression line fitted to this plot. The corrected optical density (COD) of each sample when tested at dilutions of 1/25, 1/50, and 1/100 was expressed as a percentage of the COD of a positive reference serum included on each plate, this value was the sample/positive (S/P) ratio. For each test, the linear relationship between the S/P ratio obtained at a dilution of 1/25, 1/50, and 1/100 and the end point titer calculated by each method was determined. In each case, the best linear relationship existed when samples were tested at a dilution of 1/100 (r = 0.973 for BVDV, 0.962 for PI3V, 0.961 for RSV, 0.947 for IBRV). From the equation of these lines, an increase in the S/P ratio between acute and convalescent serum samples of 31%, 23%, 21%, and 35% would correspond to a 4-fold rise in ELISA titer to BVDV, PI3V, RSV, and IBRV, respectively. ELISA titers calculated from S/P ratios at 1/100 were significantly related to virus neutralization titers to BVDV, RSV, and IBRV and to hemagglutination inhibition titers to PI3V (P < < 0.001 in all cases). Samples with low S/P ratios had the greatest intraassay and interassay variation. Intraassay reproducibility ranged from 3.5% to 22.3% (coefficient of variation), with a median value of 9.5%. Interassay reproducibility was lower, ranging from 6.0% to 50.6%, with a median of 17.4%.


Asunto(s)
Anticuerpos Antivirales/sangre , Diarrea Mucosa Bovina Viral/diagnóstico , Enfermedades de los Bovinos , Rinotraqueítis Infecciosa Bovina/diagnóstico , Infecciones por Virus Sincitial Respiratorio/veterinaria , Infecciones por Respirovirus/veterinaria , Animales , Diarrea Mucosa Bovina Viral/sangre , Diarrea Mucosa Bovina Viral/inmunología , Bovinos , Virus de la Diarrea Viral Bovina/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/normas , Ensayo de Inmunoadsorción Enzimática/veterinaria , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/inmunología , Control de Calidad , Análisis de Regresión , Reproducibilidad de los Resultados , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Infecciones por Virus Sincitial Respiratorio/inmunología , Virus Sincitiales Respiratorios/inmunología , Respirovirus/inmunología , Infecciones por Respirovirus/diagnóstico , Infecciones por Respirovirus/inmunología , Sensibilidad y Especificidad
14.
Prev Vet Med ; 49(1-2): 1-17, 2001 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-11267684

RESUMEN

Traditionally, the planning of surveys (in particular, sample-size calculations) has relied on assumptions including the assumption of perfect screening tests. This paper presents a novel approach that can be used for planning animal-health surveys and interpreting screening-test results in the context of these surveys. A stochastic simulation model developed to assess the properties of herd-level sampling schemes and surveys has been adapted for large surveys aimed at substantiating freedom from infection at a national or regional level. We use a Bayesian approach to derive the post-survey probability of freedom from infection from the pre-survey probability of freedom and the likelihood ratio that is associated with screening-test results. We applied the model to two consecutive surveys conducted in 1998 and 1999 in Switzerland to substantiate freedom from infectious bovine rhinotracheitis (IBR) in the cattle population of about 56000 herds (median herd size of 15 cattle > 2 yr of age in 1999). In 1998, serum samples were taken from five cattle > 2 yr in 4672 herds, and in 1999 from all cattle > 2 yr old in 648 herds; samples were analysed by ELISA. The survey of 1999 provided less evidence than that of 1998 to support a status of freedom from infection; also, the characteristics of both herd-level sampling schemes were similar. We argue that the rationale for survey planning depends on the pre-survey probability of freedom from infection (i.e. our level of confidence that the infection does not occur in the targeted animal population). In consequence, surveys should be tailored to individual populations in the respective countries or regions. The model has been developed in an Excel spreadsheet to allow flexibility of use, and adaptation to many other animal-health issues.


Asunto(s)
Anticuerpos Antivirales/sangre , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/epidemiología , Rinotraqueítis Infecciosa Bovina/prevención & control , Tamizaje Masivo/veterinaria , Procesos Estocásticos , Animales , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Herpesvirus Bovino 1/aislamiento & purificación , Rinotraqueítis Infecciosa Bovina/sangre , Tamizaje Masivo/métodos , Leche/virología , Suiza/epidemiología
15.
Prev Vet Med ; 32(3-4): 219-34, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9443329

RESUMEN

The relative variability of the sero-prevalence of antibodies to infectious bovine rhinotracheitis (IBR) due to cow, farm, and agroecological area levels were investigated for three contrasting districts in Kenya: Samburu, an arid and pastoral area; Kiambu, a tropical highland area; and Kilifi, a typical tropical coastal area. Cattle were selected by two-stage cluster sampling and visited once between August 1991 and 1992. Data on animal, farm, and area factors were analyzed using Schall's algorithm and MLn (multi-level, n-level), two generalized mixed-model programs suitable for multi-level analysis. Most variation in IBR sero-prevalence was from farm-to-farm. This was reflected by the many farm-level fixed effects (farm size, disease control measures and type of breeding) significant in models both ignoring and accounting for single variance components (clustering) at farm, area, and district levels. Area-to-area and district-to-district variations were noted but the area and district variance components were one-third and one-fifth the size of the farm variance components for both methods. As farm-to-farm variation differed markedly by farm size and district, models in MLn were extended to allow for multiple farm-level variance components by these categories. For each, sero-prevalence of IBR increased with age and was significantly decreased on small-sized zero-grazing farms. These models, particularly the model with different farm variance components by districts, fit the data better and highlighted well that there was considerable farm-to-farm variation--differing by district--and that the available farm-level fixed effects did not predict IBR sero-prevalence well.


Asunto(s)
Anticuerpos Antivirales/sangre , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/epidemiología , Rinotraqueítis Infecciosa Bovina/inmunología , Modelos Estadísticos , Algoritmos , Animales , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/inmunología , Bovinos , Análisis por Conglomerados , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Rinotraqueítis Infecciosa Bovina/sangre , Kenia/epidemiología , Modelos Lineales , Análisis Multivariante , Prevalencia , Factores de Riesgo
16.
Theriogenology ; 51(5): 875-81, 1999 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-10729010

RESUMEN

We determined the prevalence of antibodies to infectious bovine rhinotracheitis virus (IBRV) and bovine viral diarrhea virus (BVDV) in sera of dairy cows on 4 different farms in the Republic of Croatia. A high percentage (60.8%) of cows had various reproductive disorders. The results showed that seroprevalence of infectious bovine rhinotracheitis (IBR) was 85.8% and that of bovine viral diarrhea (BVD) was 79.2% in tested cows. Antibodies to both viruses were found in 80.8% of cows with reproductive disorders but in only 46.8% of cows without reproductive disorders. This difference was statistically significant (P<0.01), and indicated a connection between reproductive disorders and simultaneous infections with IBR and BVD viruses in dairy cows.


Asunto(s)
Anticuerpos Antivirales/sangre , Diarrea Mucosa Bovina Viral/epidemiología , Virus de la Diarrea Viral Bovina/inmunología , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/epidemiología , Aborto Veterinario/virología , Animales , Diarrea Mucosa Bovina Viral/sangre , Diarrea Mucosa Bovina Viral/inmunología , Bovinos , Croacia/epidemiología , Virus de la Diarrea Viral Bovina/aislamiento & purificación , Femenino , Herpesvirus Bovino 1/aislamiento & purificación , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/inmunología , Pruebas de Neutralización/veterinaria , Enfermedades del Ovario/veterinaria , Enfermedades del Ovario/virología , Embarazo , Estudios Seroepidemiológicos , Enfermedades Uterinas/veterinaria , Enfermedades Uterinas/virología
17.
Res Vet Sci ; 45(2): 198-205, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2848301

RESUMEN

Peripheral blood mononuclear cells (PBMC) from calves infected with bovine herpesvirus type 1 (BHV1) or parainfluenza 3 virus (PI3) were cultured in vitro in the presence of inactivated specific antigen presented on MDBK cells. In the presence of inactivated antigen, PBMC from both BHV1-infected and control calves produced interferon (IFN)-alpha in 24 hour cultures. Altering the culture conditions did not result in the detection of immune-specific IFN produced by mononuclear cells from BHV1-infected calves. However, spontaneous IFN was detected in the absence of antigen in 24 hour cultures from infected animals: this IFN was pH 2 labile and completely neutralised by antiserum to recombinant bovine IFN-gamma. Spontaneous IFN-gamma production was only seen in calves following a second BHV1 inoculation, given four to seven weeks after the primary dose. In contrast PBMC cultures from PI3 virus-infected calves did not produce IFN-gamma spontaneously, but did so in cultures which contained inactivated PI3 antigen. Mononuclear cells from control animals failed to produce either IFN-alpha or -gamma when cultured with inactivated PI3 virus. IFN-gamma was detected in PBMC cultures after the primary infection, with no increase in production occurring following subsequent PI3 virus inoculations. Immunospecific production of IFN-gamma provides a simple method for monitoring cell-mediated immunity in BHV1- and PI3 virus-infected calves and can be used for evaluating the efficacy of vaccines against these viruses.


Asunto(s)
Enfermedades de los Bovinos/inmunología , Rinotraqueítis Infecciosa Bovina/inmunología , Interferón gamma/biosíntesis , Leucocitos Mononucleares/inmunología , Infecciones por Paramyxoviridae/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/sangre , Enfermedades de los Bovinos/microbiología , Células Cultivadas , Inmunidad Celular , Rinotraqueítis Infecciosa Bovina/sangre , Virus de la Parainfluenza 3 Humana , Infecciones por Paramyxoviridae/sangre , Infecciones por Paramyxoviridae/inmunología
18.
J Anim Sci ; 68(9): 2893-900, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2211419

RESUMEN

The relationship between serum minerals and stress and(or) disease has not been fully evaluated in beef cattle. Two trials were conducted to determine the changes in serum Cu and Zn during market-transit stress and(or) disease. Two additional trials were conducted to determine the changes in serum Cu and Zn after inoculation with infectious bovine rhinotracheitis virus (IBRV), with one of the trials determining the changes in serum Ca and P. Trials 1 (n = 80) and 2 (n = 100) utilized calves that were handled through a normal market-transit system and transported 1,967 km to the feedlot. Trials 3 (n = 37) and 4 (n = 8) used calves that were sero-negative to IBRV and then challenged with 2.7 x 10(5) plaque-forming units of the virus. Serum samples were collected at specified intervals and serum minerals were measured for each trial. Serum Zn for morbid or IBRV-challenged calves was decreased by 34, 57, 29 and 15% (P less than .05) for the four trials, respectively, at peak morbidity. Serum Cu of morbid or IBRV-challenged calves increased 5, 15, 40 and 33% for the four trials, respectively, at peak morbidity. Feed intakes were lower during morbidity for market-transit trials and after IBRV inoculation. Lower feed intake could partially explain the decrease in serum Zn; however, when feed intake was held constant, serum Zn concentration still decreased. Serum Zn decreased and serum Cu increased during market-transit morbidity or after IBRV.


Asunto(s)
Enfermedades de los Bovinos/sangre , Rinotraqueítis Infecciosa Bovina/sangre , Minerales/sangre , Enfermedades Respiratorias/veterinaria , Estrés Fisiológico/veterinaria , Animales , Calcio/sangre , Bovinos , Cobre/sangre , Cobre/orina , Ingestión de Alimentos , Rinotraqueítis Infecciosa Bovina/complicaciones , Masculino , Fósforo/sangre , Enfermedades Respiratorias/sangre , Enfermedades Respiratorias/complicaciones , Estrés Fisiológico/sangre , Estrés Fisiológico/complicaciones , Transportes , Zinc/sangre , Zinc/orina
19.
J Anim Sci ; 72(1): 212-9, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8138492

RESUMEN

Two experiments were conducted using feeder calves in a randomized block design to determine the effects of organic and inorganic sources of Zn and Mn fed pre- and posttransit (Exp. 1 and 2) with or without injectable Cu (Exp. 2) on DMI, rectal temperature, BW changes, and plasma Zn and Cu concentrations of feedlot steers challenged with infectious bovine rhinotracheitis virus (IBRV). In Exp. 1, before weaning, all steers and their dams received the following free-choice mineral supplements: 1) control (no supplemental Zn or Mn), 2) ZnO+MnO (ZnMnO), and 3) Zn methionine+Mn methionine (ZnMnMet). In Exp. 2, 18 d before weaning and shipping, steers were allotted into two groups (22 steers/group) and fed 225 mg of Zn.steer-1 x d-1 in .9 kg of ground corn as ZnO or ZnMet. Half of the steers from each group were injected (s.c.) with 120 mg of Cu from Cu glycinate. Steers (Exp. 1 and 2) were weaned and shipped approximately 2,500 km to the feedlot, where they received the same supplements in the form of a complete diet for 34 d, during which time calves recovered from the stress due to shipment. All steers were initially sero-negative to IBRV. On d 34 (d 0 of IBRV), all steers were challenged with IBRV and DMI, rectal temperature, and BW change were monitored for 28 d.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cobre/uso terapéutico , Rinotraqueítis Infecciosa Bovina/tratamiento farmacológico , Manganeso/uso terapéutico , Zinc/uso terapéutico , Administración Oral , Animales , Temperatura Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Bovinos , Cobre/administración & dosificación , Cobre/sangre , Dieta , Ingestión de Alimentos/efectos de los fármacos , Rinotraqueítis Infecciosa Bovina/sangre , Rinotraqueítis Infecciosa Bovina/metabolismo , Inyecciones Subcutáneas/veterinaria , Masculino , Manganeso/administración & dosificación , Zinc/administración & dosificación , Zinc/sangre
20.
J Vet Med Sci ; 63(1): 61-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11217066

RESUMEN

Haptoglobin (Hp) is a hemoglobin (Hb)-binding acute-phase protein. Besides its relevance in inflammation, Hp is involved in the regulation of lipid metabolism. In cattle, in addition to the lipoprotein-deficient fraction, Hp is distributed in high-density lipoprotein (HDL) and very high-density lipoprotein (VHDL) fractions. The purpose of this study was to determine Hp concentrations in the lipoprotein fractions using an enzyme-linked immunosorbent assay (ELISA) based on the affinity with Hb, and also to detect structural differences of HDL Hp from that in the lipoprotein-deficient fraction using 2-dimensional electrophoresis. When purified Hp was used as the antigen for the ELISA, the detection limit was 7.4 ng/ml and linearity was obtained from 14.8 to 475 ng/ml. The correlation coefficient between the ELISA and single radial immunodiffusion was 0.884. The ELISA was shown to be applicable to evaluate Hp concentrations in the lipoprotein fractions. Hp concentrations in the lipoprotein fractions were in the range of 0.94 to 8.77 microg of Hp/ml (n = 4), and concentration ratios were 0.2 to 0.3% of whole serum Hp. Of the lipoprotein fractions, Hp was most abundant in HDL, moderate in VHDL and faint in chylomicrons, the very low-density lipoprotein fraction and low-density lipoprotein fraction. By 2-dimensional electrophoresis, alpha- and beta-chains of serum Hp were each separated into 5 spots, and their isoelectric point (pI) values were from 5.05 to 6.28 in the alpha-chain and from 5.92 to 6.95 in the beta-chain. The pI values of HDL Hp were indistinguishable from those of serum Hp. These results indicate that the ELISA based on the affinity with Hb is useful for evaluating Hp concentrations in lipoprotein fractions, and also suggest that HDL Hp is structurally similar to that in the lipoprotein-deficient fraction.


Asunto(s)
Haptoglobinas/análisis , Rinotraqueítis Infecciosa Bovina/sangre , Lipoproteínas HDL/sangre , Mastitis Bovina/sangre , Animales , Bovinos , Enfermedades de los Bovinos/sangre , Electroforesis en Gel Bidimensional , Ensayo de Inmunoadsorción Enzimática , Infecciones por Escherichia coli/sangre , Infecciones por Escherichia coli/veterinaria , Femenino , Inflamación , Infecciones por Klebsiella/sangre , Infecciones por Klebsiella/veterinaria , Peso Molecular , Neumonía/sangre , Neumonía/veterinaria , Valores de Referencia
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