Inactivated Bovine Viral Diarrhea Virus Research Articles

Effect of maternal cells transferred with colostrum on cellular responses to pathogen antigens in neonatal calves

To assess the effect of maternal cells or cellular components on neonatal immune responses to intracellular pathogens in calves. 15 Holstein calves. Calves were fed whole colostrum, frozen colostrum, or cell-free colostrum within 4 hours after birth. Leukocytes were obtained from calves before feeding colostrum and 1, 2, 7, 14, 21, and 28 days after ingestion. Proliferative responses against bovine viral diarrhea virus (BVDV) and mycobacterial purified protein derivatives were evaluated. Dams received a vaccine containing inactivated BVDV, but were not vaccinated against mycobacterial antigens. All calves had essentially no IgG in circulation at birth, but comparable and substantial concentrations by day 1. Calves that received whole colostrum had enhanced responses to BVDV antigen 1 and 2 days after ingestion of colostrum. In contrast, calves that received frozen colostrum or cell-free colostrum did not respond to BVDV. No differences were identified among the 3 groups in response to mycobacterial antigens. Results indicated that transfer of live maternal cells from colostrum to neonatal calves enhanced responses to antigens against which the dams had previously responded (BVDV), but not to antigens to which the dams were naïve (mycobacterial purified protein derivatives). Results suggested that cell-mediated immune transfer to neonates can be enhanced by maternal vaccination.

Evaluation of the induction of NS3 specific BVDV antibodies using a commercial inactivated BVDV vaccine in immunization and challenge trials

In order to evaluate whether cattle vaccinated with an inactivated vaccine against bovine viral diarrhoea virus (BVDV) can be differentiated serologically from BVDV infected animals, two different aspects were investigated. Firstly the antibody response against non-structural proteins (NS) was measured after multiple vaccinations of cattle with a single or double dose of a commercially available inactivated BVDV vaccine. In a second study, the animals were first vaccinated with the product, and then infected with BVDV. The antibody response was determined in four different commercial ELISA systems. It can be concluded, that the inactivated BVD vaccine exhibits properties of a marker vaccine when an appropriate antibody NS3 ELISA is applied: after vaccination NS3-specific antibody levels are low or undetectable, but the vaccination does in the present study not show any interference with the development of antibodies against NS3 after subsequent field virus infection.

Fetal Protection Against Continuous Exposure To Bovine Viral Diarrhea Virus Following Administration of A Vaccine Containing an Inactivated BVDV Fraction

Bovine viral diarrhea virus (BVDV) is a major viral pathogen of cattle, leading to substantial economic losses. A major source of loss is attributed to fetal infection with subsequent fetal pathology. The major source of virus transmission is cattle that are immunotolerant and persistently infected with BVDV. The objective of this study was to determine if a commercially available killed BVDV vaccine (CattleMasterR® Gold TM FP™ L5, Pfizer Animal Health) could protect cattle against viremia and fetal infection during continuous exposure to cattle persistently infected with the BVDV. This type of model may more closely represent natural challenge, including continuous exposure to multiple virus strains.

Avaliação da capacidade adjuvante do cloreto de dimetildioctadecilamônio associado ao hidróxido de alumínio na indução da resposta imune humoral de bovinos vacinados com o vírus da diarréia viral bovina

The humoral immune response of cattle vaccinated with inactivated bovine viral diarrhea virus (BVDV) using the association of dimethyl dioctadecyl ammonium chloride (DDA-chloride) and aluminum hydroxide (vaccine B) as adjuvant, was compared with the same antigenic formulation adsorbed with only aluminum hydroxide (vaccine A). The neutralizing antibodies titers were assessed two weeks after the second vaccine dose. The animals that received vaccine B had better humoral responses than the calves vaccinated with vaccine A. The mean titers of neutralizing antibodies, expressed in Log2, for the calves that received vaccine B was higher to those observed in group vaccinated with vaccine A. These results show that the inclusion of DDA chloride in vaccine formulations adsorbed with aluminum hydroxide determine a better humoral immune response in cattle vaccinated with BVDV inactivated.

Assessment of the clinical and virological protection provided by a commercial inactivated bovine viral diarrhoea virus genotype 1 vaccine against a BVDV genotype 2 challenge

A new genotype of bovine viral diarrhoea virus (BvDv), designated BVDV-2, has emerged in the last decade and in recent years the prevalence of BVDV-2 strains has increased. A vaccination-challenge...

Antibody responses of naive cattle to two inactivated bovine viral diarrhoea virus vaccines, measured by indirect and blocking ELISAs and virus neutralisation

Two groups of naive heifers were given primary courses of two inactivated bovine viral diarrhoea (BVD) virus vaccines licensed for use in the UK. Their humoral responses in serum and...

Method for Detection of Extraneous Active Bovine Viral Diarrhoea Virus and Classical Swine Fever Virus in Animal Viral Vaccines by RT-PCR, Which Amplify Negative-strand Viral RNA in Infected Cells

An oligonucleotide sense primer, Pst324α, was designed and used for synthesizing cDNA from negative-strand viral RNA in infected cells and used for rapid detection of active extraneous bovine viral diarrhoea virus (BVDV) and classical swine fever virus (CSFV) in animal viral vaccines by culturing a sample in cells followed by reverse transcriptase–polymerase chain reaction (RT-PCR). Active and inactivated viruses of BVDV No. 12–43 strain and CSFV GPE−strain were inoculated to bovine testicle and swine testicle cells for incubation. After the complete extraction of RNA from these cells, cDNA was synthesized using Pst324α, and PCR was carried out using primers 324 and 326 (novel RT-PCR). Amplification of novel RT-PCR products was observed in cells infected with active viruses but not in cells inoculated with inactivated viruses, inoculums and cultured media after incubation. This novel RT-PCR was able to amplify viral sequences from cells infected with only a small number of infectious particles (less than 10 TCID50) at three days postinoculation and was as sensitive as the general RT-PCR using a random primer and the interference and immunofluorescent antibody (FA) methods. The results of experiments on detection of BVDV RNA from vaccines contaminated with active and inactivated BVDV showed that the sensitivity of the novel RT-PCR was almost the same as the sensitivities of the interference and FA methods. These results suggest that the novel RT-PCR is easier and more rapid than the interference method for detection of active BVDV and that the novel RT-PCR is a reliable means for detection of active extraneous BVDV for quality control of animal vaccines.

Bovine viral diarrhea virus types 1 and 2 antibody response in calves receiving modified live virus or inactivated vaccines

Serums from calves receiving eight different commercial vaccines containing modified live virus (MLV) or inactivated bovine viral diarrhea virus (BVDV) immunogens were assayed for antibodies to types 1 and 2 BVDV strains. The immune response to the types 1 and 2 BVDV strains were evaluated in 48 calves receiving one of the eight vaccines for each group. For 7/8 vaccines, the BVDV vaccine immunogen was only type 1 whereas the remaining vaccine contained both types 1 and 2 immunogens. Calves administered MLV vaccine received only one dose at day 0, whereas those calves receiving the inactivated vaccines were administered two doses initially at days 0 and 28. Selected calves were revaccinated with only one dose at day 140. Animals vaccinated with type 1 vaccines developed titers to a broad range of type 1 BVDV, both cytopathic (CP) and noncytopathic (NCP) biotypes, with lower titers evident to type 2 BVDV strains. For some animals, the BVDV serum antibodies did not persist. Revaccination at day 140 induced a significant four-fold increase in animals with intermediate to low antibody titers. There did not appear to be any clear differences in antibody responses between type 1 MLV or inactivated vaccines. The calves receiving the inactivated vaccine containing types 1 and 2 had similar antibody levels to both types.

A case report: evidence for type 2 bovine viral diarrhea virus (BVDV)-associated disease in beef herds vaccinated with a modified-live type 1 BVDV vaccine.

Fetal infections with bovine viral diarrhea virus (BVDV) may result in infertility, abortions, stillbirths, developmental anomalies, and weak calves.1 Infection of the fetus from 58 to 120 days of gestation may create persistently infected (PI) calves that shed the virus continuously and perpetuate the herd infection.10,11 In beef herds, calf losses and PI calves have a significant impact on herd productivity.14 Vaccination with modified live virus (MLV) BVDV vaccines is commonly practiced in Wyoming beef herds to prevent reproductive losses due to BVDV infection. However, the majority of BVDV isolates obtained at the Wyoming State Veterinary Laboratory (WSVL) are from vaccinated herds. For example, in 1996 BVDV was isolated from 30 herds for which vaccination histories were available. Twenty-four herds had a history of BVDV vaccination and 6 were not vaccinated for BVDV. BVDV-associated diseases in beef herds vaccinated with inactivated BVDV vaccines have been reported.8,9 Here, we describe the isolation of type 2 BVDV-associated reproductive losses in beef herds where the cows were vaccinated with a type 1a MLV-BVDV vaccinea and the use of serology to detect BVDV infection retrospectively. In the fall of 1995, 28 cow–calf herds located in Weston County, Wyoming, had unusually high infertility rates followed by abortions, stillbirths, and weak calves in the spring of 1996. In 9 herds, the dams were vaccinated with the type 1a MLV-BVDV vaccine.a Gross findings in aborted fetuses and neonatal calves included hemorrhage in the subcutaneous tissues of lower extremities, muscle, and myocardium and on the serosal surfaces of multiple organs, serosanguinous fluid in thorax and abdominal cavities, and lens opacities. Fourteen animal tissue samples from 13 ranches were submitted. These animals included 5 fetuses, 6 neonatal calves, 2 calves 1 and 5 months of age, and a yearling steer. Two of the fetuses were autolyzed, and the remaining tissues were collected 15 minutes to 18 hours postmortem. Virus isolations (VI) were performed using 10% tissue homogenates in Bovarnick’s solution (0.218 M sucrose, 3 mM KH2PO4, 7.2 mM K2HPO4, 5.4 mM L-glutamic acid, 500 mg/liter streptomycin, 0.001% phenol red, pH 7.2) clarified by centrifugation and used to inoculate primary bovine embryonic testicle (BeT) cells previously tested and found negative for adventitial BVDV infection. Inoculated BeT cells were passed twice and stained for BVDV using monoclonal antibody 20.10.6b and fluorescein isothiocyanate-conjugated goat anti-mouse antibodyc as previously described.18 Blood samples from calves were collected from the jugular

Neutralizing antibodies to type 1 and 2 bovine viral diarrhea viruses: detection by inhibition of viral cytopathology and infectivity by immunoperoxidase assay.

Neutralizing antibodies to type 1 and 2 bovine viral diarrhea virus (BVDV) strains were measured by a microtiter virus neutralization test (MVNT) in cell culture. Antibodies (neutralizing) were detected by inhibition of viral infectivity, by the absence of viral cytopathology for cytopathic strains, or by immunoperoxidase staining for noncytopathic strains. The immunoperoxidase-stained monolayers could be detected without the aid of light microscopy. Twenty BVDV strains were used as challenge viruses in the in vitro MVNT, including 14 type 1 and 6 type 2 strains. Representative noncytopathic and cytopathic strains of both types were used. Positive control serum samples available for diagnostic testing contained both type 1 and type 2 BVDV antibodies. There did not appear to be major differences in antibody titers among the respective type strains, regardless of biotype (cytopathic or noncytopathic). In a study with sera from calves receiving a modified live virus or inactivated BVDV vaccine, the calves receiving type 1 strains responded with higher antibody titers to type 1 strains than to type 2 strains.

Foetal infections with bovine viraldiarrhoea virus in Argentina

The frequency of isolation of bovine viral diarrhoea virus (BVDV) from primary tissue cultures and organs from bovine foetuses was studied between 1992 and 1994. Around 25% of primary tissue cultures were BVDV positive. Primary testis cultures were inoculated with homogenates of spleen, kidney, lung and liver from 52 foetuses. Cells were passaged twice and BVDV antigen investigated by indirect immunofluorescence. Non-cytopathic BVDV was detected in at least one organ in 11/52 foetuses (21.2%): 6/10 spleens, 4/7 kidneys, 7/9 lungs and 3/5 livers. Cytopathic BVDV was detected in lung and kidney from two foetuses. Since only gamma-irradiated sera are used in the laboratory and only inactivated BVDV vaccines are applied in Argentina, it was concluded that these isolations represented field infections. In addition to the 11 virus positive foetuses, two foetuses were positive for BVDV antibodies, which suggested a 25% prevalence of infection. These results stress the need for disease control on a herd basis and the requirement for biological reagents of bovine origin for the detection of BVDV.

Range of viral neutralizing activity and molecular specificity of antibodies induced in cattle by inactivated bovine viral diarrhea virus vaccines

Summary The range of neutralizing activity to bovine viral diarrhea (bvd) virus and viral protein specificity of antibodies induced by 3 inactivated vaccines were evaluated by use of samples of sera obtained from 13 cattle 14 days after vaccination. Viral neutralizing antibodies were detected in all cattle to each of 10 noncytopathic and 10 cytopathic isolates of bvd virus. A viral-induced polypeptide (53,000 to 56,000 daltons) was detected by radioimmunoprecipitation with serum from all vaccinates. Other viral-induced polypeptides of 115,000, 80,000, 48,000, and 25,000 daltons were precipitated with sera from some vaccinates. Precipitation of those polypeptides was related to the vaccine used. When multiple viral polypeptides were precipitated, the 53,000- to 56,000-dalton polypeptide appeared immunodominant.

Flow cytofluorimetric analysis of lymphocyte subset alterations in cattle infected with bovine viral diarrhea virus.

Clinically normal, bovine viral diarrhea virus (BVDV)-seronegative, 7 to 9-month-old steers were inoculated intranasally with NY-1, a noncytopathic strain of BVDV, or exposed intramuscularly to killed BVDV. Indirect immunofluorescence staining with monoclonal antibodies specific for bovine leukocyte subsets followed by flow cytometric analysis was used to monitor subsequent hematologic alterations. Infection with BVDV resulted in a transient leukopenia which was characterized by decreases in the absolute numbers of circulating T lymphocytes, including BoT4+ ("helper") and BoT8+ ("cytotoxic/suppressor") subsets, B lymphocytes, and neutrophils. There was no significant variation in numbers of non-T, non-B ("null") lymphocytes or monocytes. Exposure to inactivated BVDV in a combination vaccine did not cause significant alteration in the circulating numbers of any major leukocyte subset; however, significant variation was seen in the BoT4/BoT8 ratios and in the numbers of cells expressing major histocompatibility complex (MHC) class II antigens.