Search Results (63)

The bovine viral diarrhoea virus (BVDV) impacts the health and performance of bovine herds. In the present retrospective study, the impact of BVDV control on the production performance of suckler herds was tested by vaccinating all female cows of the herd on the same day (DV). The performance of cows in two commercial suckler herds was analysed during 12 months before DV (PREVAC, n = 497 cows) and 9 to 21 months after vaccination (POSTVAC, n = 531 cows). The proportion of calves born compared to the initial number of cows subjected to mating did not differ (PREVAC and POSTVAC, 87% and 84%, respectively). The proportion of calves weaned compared to the initial number of cows subjected to mating also did not differ between PREVAC (71%) and POSTVAC (74%). However, the proportion of calves weaned compared to the number of calves born was higher than POSTVAC (87%) when compared to PREVAC (81%). Thus, the data demonstrate that a BVDV control programme using vaccination in suckler herds can improve calf survival. Full article

Background/Objectives: This study aimed to determine the changes in BVDV (bovine viral diarrhea virus), BoHV-1 (bovine herpesvirus-1), and BRSV (bovine respiratory syncytial virus) antibody levels until weaning in calves who ingested colostrum from vaccinated dairy cattle. Additionally, it aimed to measure the antibody levels induced by the vaccine administered before and after socialization after weaning. Methods: Exposure to respiratory viral and bacterial agents was monitored by PCR analysis using nasal swabs at regular intervals from birth to weaning (pre-colostral and after the 2nd, 7th, 15th, 25th, 35th, 45th, 55th, and 65th days). The levels of colostral BVDV, BoHV-1, and BRSV antibodies were monitored using an enzyme-linked immunosorbent assay (ELISA) at the same intervals from birth to weaning (pre-colostral and after the 2nd, 7th, 15th, 25th, 35th, 45th, 55th, and 65th days). Results: The highest level of maternal antibodies in the blood was detected on day 7. BoHV-1, BVDV, and BRSV antibody levels decreased steadily until weaning by 69.14%, 38%, and 53%, respectively. Conclusions: Vaccination strategies should be planned by considering the presence of maternally derived antibodies and minimizing stress that may negatively affect vaccine titers, thus maximizing vaccine efficacy in calves. Full article

Background/Objectives: Bovine viral diarrhea virus (BVDV) causes significant economic losses in the cattle industry worldwide. The current vaccines have limited efficacy against diverse BVDV genotypes. Currently, multi-antigen target design and nanocarrier display technologies can provide ideas for broad-spectrum and efficient BVDV vaccine design. Methods: Here we developed a trivalent mRNA vaccine encoding the domains I-II of envelope glycoprotein E2 from three BVDV genotypes (3E2), introduced with bovine IgG1 Fc (bFc), STABILON (hStab), and artificial virus-like particle (ARVLP) containing CD80 transmembrane (TM) domain, FcγRII cytoplasmic domain, and WW domain of ITCH. Then, in vitro expression, in vivo immunogenicity and neutralizing antibody analysis were performed to evaluate the vaccines. Results: The in vitro expression results showed that bFc and hStab dramatically enhanced antigen expression and immunogenicity. In addition, the ARVLP further enhanced the secretion and potency of neutralizing antibodies. Finally, the immunogenicity of the bFc_BVDV_3E2_ARVLP_hStab mRNA vaccine was evaluated in mice, guinea pigs, and lactating goats and high levels of neutralizing antibodies against all three BVDV genotypes were detected. Conclusions: Our trivalent design strategy with bFc, hStab, and ARVLP shows highly efficient expression as well as strong immunogenicity and provides a promising approach for next-generation BVDV vaccines with broader and stronger protection. Full article

Bovine pestiviruses, namely bovine viral diarrhea virus (BVDV) and HoBi-like pestiviruses (HoBiPevs), are endemic viruses in Latin America, and the disease causes significant losses in the agricultural sector. The present review aims to perform a systematic assessment and meta-analysis of the prevalence of bovine pestiviruses in Latin America and their risk factors. Notable heterogeneity was observed in the analyzed groups, with significant prevalence variations based on age and country. However, no differences were found between temporal trends, production systems, or models. Identified risk factors included age, breed, location, reproductive practices, animal purchase, farm management, and biosecurity measures. This systematic review and meta-analysis of BVDV in Latin America provides critical insights to inform decision-making and strategic actions for disease control in the region. The high serological prevalence of bovine pestivirus across Latin America underscores the urgent need for standardized surveillance programs, biosecurity reinforcement, and targeted vaccination strategies. The presence of HoBiPev further complicates current diagnostic and control measures. Future research should focus on disease transmission dynamics, economic impact assessments, and the effectiveness of intervention programs tailored to the region’s diverse livestock production systems. Full article

Bovine viral diarrhea (BVD) is caused by bovine viral diarrhea virus (BVDV), a member of the genus Pestivirus and in the family Flaviviridae. According to some studies, the disease incurs USD 1.5–2.5 billion per year and USD 0.50 to USD 687.80 per cow loss in beef and dairy farms, respectively. Using vaccines is among the strategies to prevent the disease. However, complete protection requires vaccines that target both the humoral and cellular immune responses of the adaptive immune system. A comprehensive literature review was made to provide insights into the interaction of BVDV with host immunity, vaccine applications, and the limitation of the currently available vaccines, as well as explore strategies used to advance the vaccines. BVDV causes immunosuppression by interfering with the innate and adaptive immune systems in a manner that is species and biotype-dependent. Interferon production, apoptosis, neutrophil activity, and antigen-processing and presenting cells are significantly affected during the viral infection. Despite maternal antibodies (MatAbs) being crucial to protect calves from early-age infection, a higher level of MatAbs are counterproductive during the immunization of calves. There are numerous inactivated or modified BVDV vaccines, most of which are made of cytopathic BVDV 1 and 2 and the BVDV 1a subgenotypes. Furthermore, subunit, marker, DNA and mRNA vaccines are made predominantly from E2, E^rns, and NS₃ proteins of the virus in combination with modern adjuvants, although the vaccines have not yet been licensed for use and are in the experimental stage. The existing BVDV vaccines target the humoral immune system, which never gives the full picture of protection without the involvement of the cell-mediated immune system. Several limitations were associated with conventional and next-generation vaccines that reduce BVDV vaccine efficiency. In general, providing complete protection against BVDV is very complex, which requires a multi-pronged approach to study factors affecting vaccine efficacy and strategies needed to improve vaccine efficacy and safety. Full article

Background/Objectives: White-tailed deer (Odocoileus virginianus) (WTD) play a central role at the human–livestock–wildlife interface, given their contribution to the spread of diseases that can affect livestock. These include a variety of bacterial, viral, and prion diseases with significant economic impact. Given the implications for WTD as potential reservoirs for a variety of diseases, methods for prevention and disease control in WTD are an important consideration. Methods: Using commercial livestock vaccines against bovine viral diarrhea virus (BVDV) in killed and modified live formulations, we test the ability of WTD to develop humoral and cellular immune responses following vaccination. Results: We demonstrate that, similar to cattle, WTD develop humoral immune responses to both killed and modified live formulations. Conclusions: As the farmed deer industry and the use of livestock vaccines in non-approved species grow, this type of information will help inform and develop improved husbandry and veterinary care practices. Additionally, while we were unable to detect cell-mediated immune responses to the vaccine, we established PrimeFlow as a method to detect IFN-γ responses in specific T cell populations, adding another level of resolution to our ability to understand WTD immune responses. Full article

Cell-mediated immunity is an important component of the immune response for intracellular pathogens. Live vaccines containing different pathogens are used concurrently in the field but are generally licensed individually. Concurrent administration of these vaccines has led to concerns about immune interference. The goal of this study was to characterize BVDV-specific responses to vaccination and determine the effect of concurrent Brucella abortus strain RB51 (RB51) vaccine administration. Peripheral blood mononuclear cells (PBMCs) from cattle vaccinated with a modified-live viral (MLV) vaccine containing BVDV, both RB51 and an MLV, or unvaccinated controls were utilized to evaluate antibody titers and the frequency of interferon gamma (IFN-γ) production within CD4⁺, CD8⁺ T cells, and NK cell populations via flow-cytometry. Our data demonstrated the lack of vaccine interference following concurrent administration of two common bovine MLVs and may even suggest some level of enhanced IFN-γ production with concurrent administration. Full article

A chimeric pestivirus KD26_E2LOM strain can induce antibodies that can be partially distinguished from antibodies from classical swine fever virus (CSFV) infection. The chimeric pestivirus vaccine strain was created using bovine viral diarrhea virus as the backbone; however, the entire BVDV E2 gene region was replaced with the E2 gene, which encodes the major target for neutralizing antibodies against CSFV. Pigs were vaccinated once or twice with the chimeric pestivirus KD26_E2LOM strain, and protective efficacy was evaluated after subsequent challenge with virulent CSFV. Pigs inoculated with the chimeric pestivirus KD26_E2LOM strain did not have a high temperature or leukopenia, and CSFV neutralizing antibodies (>64-fold) were observed from 28 days postvaccination (dpv). In addition, the level of anti-CSFV E2 antibody positivity was >0.8 (s/p value) from 30 dpv, and there were no antibody-positive individuals among the sentinel pigs. In control pigs, CSF antigen was detected in blood, nasal, and fecal samples at 5, 7, 10, 14, and 21 days postchallenge (dpc) and in several organs; however, no CSFV was detected in the organs of pigs vaccinated with the chimeric pestivirus KD26_E2LOM strain, and no virus shedding or CSF antigen was detected on any dpc. Thus, the chimeric pestivirus KD26_E2LOM strain protects pigs against horizontal transmission of virulent CSFV; however, this strain may have only partial potential for the differential detection of CSFV E^rns antibodies. Full article

Objective: This study evaluated the effect of a novel subunit-targeted vaccine against BVDV in six dairy farms in Argentina. Methods: Reproductive, health, and production parameters—including conception and abortion rates, open days, calves born per insemination, as well as newborn and overall mortality, and milk production—were monitored over a ten-year period (2014–2023). Data were analyzed annually to assess trends and compare the periods before and after vaccine introduction. Results: All parameters showed significant improvement after vaccine incorporation, with an 11% increase in conception rate, a 5% reduction in abortion rate, a 12% increase in calves per insemination rate, and a decrease of 11 open days (8.4%). Additionally, newborn mortality and overall mortality decreased by 33% and 16%, respectively, while milk production increased by 9%. These data were also compared with eight non-vaccinated dairy farms, and significant differences were observed in health and reproductive parameters. Conclusions: These findings indicate that vaccination with an effective non-replicating subunit vaccine can successfully minimize the impact of BVDV in dairy farms. Full article

Mycoplasma, reticuloendotheliosis virus (REV), avian leukosis virus (ALV), chicken infectious anemia virus (CIAV), bovine polyomavirus (BPV), bovine viral diarrhea virus (BVDV), and porcine circovirus (PCV) are considered common contaminants in live veterinary vaccines against Newcastle disease virus (NDV), fowlpox virus (FPV), infectious bursal disease virus (IBDV), classical swine fever virus (CSFV), pseudorabies virus (PRV), and porcine reproductive and respiratory syndrome virus (PRRSV). In the past five years, Getah virus (GETV), an arbovirus affecting many farming mammals, was reported as a new contaminant in live PRRSV vaccines in two previous studies, which arouses our considerable interest. Therefore, in this paper, we aim to analyze and discuss the source, biological hazard, and genomic characteristics of these contaminating GETV strains further. Full article

Bovine viral diarrhea (BVD) is caused by the BVD virus (BVDV) and has been reported worldwide in cattle. To estimate BVDV circulation among cattle where few BVD cases were reported in southern Japan, 1910 serum samples collected from 35 cattle farms without a BVD outbreak were investigated to detect antibodies against BVDV-1 and BVDV-2 using an indicator virus with a cytopathogenic effect and the luciferase gene, respectively. Neutralizing antibodies against BVDV-1 and BVDV-2 were detected more frequently in 18 vaccinated farms than in 17 nonvaccinated farms. In the nonvaccinated farms, 9.6%, 1.8%, and 13.8% of the cattle were estimated to have a history of infection with BVDV-1, BVDV-2, and both, respectively. The median rate of within-herd anti-BVDV-1 seropositivity among cattle in the nonvaccinated farms was 22.0%; however, a high within-herd seropositivity (>50%) was confirmed in the two farms. The force of infection, basic reproduction number, and annual probability of BVDV-1 infection were estimated as 0.072 (95% confidence interval [CI]: 0.062–0.084), 0.36 (95% CI: 0.31–0.42), and 0.73% (95% CI: 0.61–0.87%), respectively, using the age-specific positive rate of anti-BVDV-1 antibodies. These parameters should be further applicable for developing epidemiological models which illustrate the BVDV dynamics in the field. Full article

A new multivalent vaccine (DIVENCE^®), containing live gE/tk double-gene-deleted BoHV-1, live-attenuated BRSV, inactivated PI3, and BVDV-1, and BVDV-2 recombinant proteins, has been designed to protect cattle against the main viral pathogens associated with bovine respiratory disease (BRD). The aim of this study was to demonstrate the efficacy of DIVENCE^® against BRD in field conditions. A total of 360 animals from three different farms were included in this study. Calves were randomly distributed to the vaccinated (n = 183; DIVENCE^®) or control (n = 177; phosphate-buffered saline solution) group. All animals received two intramuscular doses (2 mL/dose) three weeks apart of the corresponding product. The entire fattening period (approximately 9 months) was monitored to assess the incidence, severity, and morbidity of BRD as well as administered treatments and growth performance. During this study, a BRSV outbreak was reported in one farm, where vaccinated animals had significantly (p < 0.02) lower morbidity (20.4%) and severity (score of 1.70) compared to the control group (53.70% and score of 2.11). Overall, vaccinated animals had a significantly lower number of cases (p < 0.001; 0.36 vs. 0.64 cases/calf), lower morbidity (p < 0.004; 26.78% vs. 41.24%), and lower antimicrobial treatments (p = 0.01; 33.3% vs. 57.4%) than control animals. Vaccinated animals presented significantly (p = 0.01) higher carcass weight than controls (6.58 kg). Vaccination with DIVENCE^® at the beginning of the fattening period decreased the incidence and morbidity of BRD following a BRSV outbreak. Additionally, the overall incidence and morbidity of BRD throughout the entire fattening period were reduced across farms. Thus, DIVENCE^® can improve economic outcomes in fattening units by reducing antibiotic treatments and enhancing performance. Full article

Porcine sapelovirus (PSV) is a new pathogen that negatively impacts the pig industry in China. Affected pigs experience severe diarrhea and even death. Vaccination is used to control disease outbreaks, and sensitive diagnostic methods that can distinguish infected animals from vaccinated animals (DIVA) are essential for monitoring the effectiveness of disease control programs. Tests based on the detection of the nonstructural protein (NSP) 3AB are reliable indicators of viral replication in infected and vaccinated animals. In this study, the recombinant PSV 3AB protein was expressed by a prokaryotic expression system, and an indirect ELISA method was established. Serum samples from healthy animals, immunized animals, and infected animals were evaluated. The ELISA method identified 3AB with high sensitivity (99.78%) and specificity (100.0%), and no cross-reaction was observed with serum antibodies against porcine reproductive and respiratory syndrome virus (PRRSV), infection with classical swine fever virus (CSFV), pseudorabies virus (PRV), bovine viral diarrhea virus (BVDV), porcine epidemic diarrhea virus (PEDV), or foot-and-mouth disease virus (FMDV). The ELISA method described here can effectively distinguish infected and vaccinated animals and is an important inexpensive tool for monitoring serum and controlling PSV. Full article

Bovine Respiratory Disease (BRD) poses a significant threat to cattle welfare worldwide, affecting their respiratory system and causing substantial economic losses. BRD is multifactorial in nature. This research aimed to investigate the serological profile of calves for the five main bovine respiratory pathogens. Serum samples were collected from dairy calves aged 7–12 months that had never been vaccinated against tested pathogens and had recently shown signs of BRD. A total of 4095 calves from 650 dairy herds located in south-western Poland were examined. The Commercial Indirect Respiratory ELISA Kit Multiplexed—Double well—BIO K 284/5 (Bio-X Diagnostics, Rochefort, Belgium) was used to determine the presence of antibodies against BVDV, BoAHV1, BRSV, BPIV3, and M. bovis. The presence of antibodies against at least one of the tested pathogens was found in 306 (47.08%) herds. The overall prevalence of antibodies was as follows: BoAHV1 21.54%, BVDV 32.0%, BRSV 34.15%, BPIV3 34.31%, and M. bovis 31.38%. The strongest correlation was between BRSV antibodies positive sera and BPIV3 antibodies positive sera. Among the five pathogens tested, antibodies to BVDV, BRSV, BPIV3, and M. bovis were most commonly detected simultaneously. The results of this study indicate the need for preventive measures against these pathogens in the studied region. Full article

Bovine viral diarrhea virus (BVDV) is an RNA virus associated with severe economic losses in animal production. Effective vaccination and viral surveillance are urgent for the prevention and control of BVDV infection. However, the application of traditional modified live vaccines and inactivated vaccines is faced with tremendous challenges. In the present study, we describe the preclinical efficacy of two BVDV mRNA vaccines tested in mice and guinea pigs, followed by a field trial in goats, where they were compared to a commercial vaccine (formaldehyde inactivated). The two mRNAs were engineered to express the envelope protein E2 of BVDV-1, the most prevalent subtype across the world, through a 5′ cap-dependent or independent fashion. Better titers of neutralizing antibodies against BVDV-1 were achieved using the capped RNA in the sera of mice and guinea pigs, with maximum values reaching 9.4 and 13.7 (by −log₂), respectively, on the 35th day post-vaccination. At the same time point, the antibody levels in goats were 9.1 and 10.2 for the capped and capless RNAs, respectively, and there were no significant differences compared to the commercial vaccine. The animals remained healthy throughout the experiment, as reflected by their normal leukogram profiles. Collectively, our findings demonstrate that mRNA vaccines have good safety and immunogenicity, and we laid a strong foundation for the further exploitation of efficient and safe BVDV vaccines. Full article