Diagnostic studies of abortion in Danish cattle 2015–2017

Abstract Background Abortion is a major source of economic losses in cattle breeding. Abortion occurs due to a wide range of causes, but infections are the most frequently diagnosed. However, establishing an aetiological diagnosis remains challenging due to the large variety of bacteria, protozoa, viruses, and fungi that have been associated with abortion in cattle. Economic restraints limit the range of diagnostic methods available for routine diagnostics, and decomposition of the conceptus or lack of proper fetal and/or maternal samples further restrict the diagnostic success. In this study, we report recent diagnostic findings from bovine abortions in Denmark, a country that has a large dairy sector and is free from most infectious agents causing epizootic abortion in cattle. The aims of the study were: (i) to identify infectious causes of bovine abortion in Denmark, (ii) to categorise the diagnostic findings based on the level of diagnostic certainty, and (iii) to assess the diagnostic rate. Due to economic restraints, only a limited panel of routine diagnostic methods were available. Placentas and/or fetuses from mid- to late-term abortions and stillbirths (n = 162) were submitted to the Danish National Veterinary Institute between January 2015 and June 2017. The aborted materials were examined macroscopically, histologically, and by bacterial culture. Maternal blood samples were tested for bovine viral diarrhoea virus (BVDV) antibodies. Results The likely aetiology of the abortion was diagnosed in 52 cases, resulting in a diagnostic rate of 33%. The most common cause was protozoal infection (19%) followed by infection with Trueperella pyogenes (3%), Staphylococcus aureus (2%), and non-haemolytic Escherichia coli (2%). Lesions in fetuses with a protozoal infection were consistent with neosporosis. In many cases (38%), inflammatory changes were found in the placenta and/or fetal organs but no specific aetiology was identified. Neither infection with Brucella spp. nor maternal BVDV antibodies were detected. The majority of submitting herds (92%) were each represented by fewer than three abortion cases over the study period. Conclusions Protozoal infection, most likely neosporosis, was the most commonly diagnosed cause of abortion and the only one associated with potential epizootic abortion events. Despite using a reduced number of diagnostic methods in comparison to other abortion studies, the diagnostic rate of this study was within the range reported in an earlier Danish study, as well as in recent international studies. The low number of submitted cases per herd and the sparse anamnestic information provided at submission hampered conclusions on the potential epizootic character of the abortion events in question.

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Eradication of Bovine Viral Diarrhoea (BVD) in Cattle in Switzerland: Lessons Taught by the Complex Biology of the Virus

Frontiers in Veterinary Science ◽

10.3389/fvets.2021.702730 ◽

2021 ◽

Vol 8 ◽

Author(s):

Matthias Schweizer ◽

Hanspeter Stalder ◽

Anja Haslebacher ◽

Martin Grisiger ◽

Heinzpeter Schwermer ◽

...

Keyword(s):

Horizontal Transmission ◽

Bovine Viral Diarrhoea Virus ◽

Control Programme ◽

Economic Losses ◽

Border Disease Virus ◽

Cattle Population ◽

Bovine Viral Diarrhoea ◽

Main Challenge ◽

Border Disease ◽

Diarrhoea Virus

Bovine viral diarrhoea virus (BVDV) and related ruminant pestiviruses occur worldwide and cause considerable economic losses in livestock and severely impair animal welfare. Switzerland started a national mandatory control programme in 2008 aiming to eradicate BVD from the Swiss cattle population. The peculiar biology of pestiviruses with the birth of persistently infected (PI) animals upon in utero infection in addition to transient infection of naïve animals requires vertical and horizontal transmission to be taken into account. Initially, every animal was tested for PI within the first year, followed by testing for the presence of virus in all newborn calves for the next four years. Prevalence of calves being born PI thus diminished substantially from around 1.4% to <0.02%, which enabled broad testing for the virus to be abandoned and switching to economically more favourable serological surveillance with vaccination being prohibited. By the end of 2020, more than 99.5% of all cattle farms in Switzerland were free of BVDV but eliminating the last remaining PI animals turned out to be a tougher nut to crack. In this review, we describe the Swiss BVD eradication scheme and the hurdles that were encountered and still remain during the implementation of the programme. The main challenge is to rapidly identify the source of infection in case of a positive result during antibody surveillance, and to efficiently protect the cattle population from re-infection, particularly in light of the endemic presence of the related pestivirus border disease virus (BDV) in sheep. As a consequence of these measures, complete eradication will (hopefully) soon be achieved, and the final step will then be the continuous documentation of freedom of disease.

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Evaluation of diagnostic methods to distinguish between calves persistently and transiently infected with bovine viral diarrhoea virus in respect to the presence of maternal antibodies

Bulletin of the Veterinary Institute in Pulawy ◽

10.2478/bvip-2013-0054 ◽

2013 ◽

Vol 57 (3) ◽

pp. 311-317

Author(s):

Magdalena Larska ◽

Aleksandra Kuta ◽

Mirosław P. Polak

Keyword(s):

Virus Detection ◽

Bovine Viral Diarrhoea Virus ◽

Diagnostic Methods ◽

Viral Rna ◽

Maternal Antibodies ◽

Bovine Viral Diarrhoea ◽

Rt Pcr ◽

Serum Samples ◽

Virus Genotype ◽

Diarrhoea Virus

Abstract Two issues concerning virus detection and identification of persistently infected (PI) cattle were analysed in the study: 1) interference by maternal antibodies and 2) discrimination between PI and transiently infected (TI) animals. Antigen ELISA and RT-PCR based methods were compared using serum samples from natural and experimental PI and TI calves. RT-PCR and realtime RT-PCR using primers within 5’UTR region were more sensitive in detecting PI animals than Erns and NS3 antigen capture ELISAs, and they were not influenced by the presence of colostral antibodies in serum or by bovine viral diarrhoea virus genotype. The serum samples with Ct values ≤ 29.10 (corresponding to 104.87 viral RNA copies/μL) identified PI animals with 100% probability, while all samples with Ct values > 32.06 (corresponding to viral RNA load below 104 copies/μL) indicated TI status. The samples with Ct values between 29.10 and 32.06 (17.2% of PI and 11.5% of TI) should be considered as PI suspect and retested.

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First-time detection of bovine viral diarrhoea virus, BVDV-1, in cattle in Botswana

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v86i1.1764 ◽

2019 ◽

Vol 86 (1) ◽

Author(s):

Sara Lysholm ◽

Solomon S. Ramabu ◽

Mikael Berg ◽

Jonas J. Wensman

Keyword(s):

Disease Transmission ◽

Bovine Viral Diarrhoea Virus ◽

Capital City ◽

Economic Losses ◽

Bovine Viral Diarrhoea ◽

Antibody Prevalence ◽

Blood Samples ◽

Prevalence Studies ◽

Diarrhoea Virus ◽

First Time

Infectious diseases are serious constraints for improving livestock productivity. Bovine viral diarrhoea virus (BVDV) is a virus causing grave economic losses throughout the cattle producing world. Infection is often not apparent, but the virus can also cause respiratory signs, diarrhoea, reproductive problems and immunosuppression. Risk factors for disease transmission include, but are not limited to, herd size, animal trade and grazing on communal pastures. Several prevalence studies have been conducted in southern Africa, but in Botswana the occurrence is largely unknown. In this study, blood samples were obtained from 100 goats from three villages around the capital city, Gaborone. Also, 364 blood samples from cattle around Gaborone, collected as part of another study, were analysed. The detected antibody prevalence was 0% in goats and 53.6% in cattle when using a competitive enzyme-linked immunoassay. Three animals from two different herds were positive for viral nucleic acids on polymerase chain reaction. The two herds with viraemic animals had significantly higher antibody prevalence compared to the other herds. Also, two of the detected viruses were sequenced and found to be most similar to BVDV-1a. To the authors’ knowledge, this is the first time that sequencing has been performed on BVDV isolated in Botswana.

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RNA-Seq based transcriptome analysis during bovine viral diarrhoea virus (BVDV) infection

BMC Genomics ◽

10.1186/s12864-019-6120-4 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 2

Author(s):

Cun Liu ◽

Yanhan Liu ◽

Lin Liang ◽

Shangjin Cui ◽

Yanming Zhang

Keyword(s):

Complement System ◽

Bovine Viral Diarrhoea Virus ◽

Descriptive Study ◽

Innate Immune ◽

Economic Losses ◽

Rna Seq ◽

Bovine Viral Diarrhoea ◽

Host Interactions ◽

Diarrhoea Virus ◽

The Complement System

Abstract Background Bovine viral diarrhoea virus (BVDV) is the member of the genus Pestivirus within the Flaviviridae family and responsible for severe economic losses in the cattle industry. BVDV can employ ‘infect-and-persist’ strategy and ‘hit-and-run’ strategy to remain associated with hosts and thus contributes to BVDV circulation in cattle herds. BVDV have also evolved various strategies to evade the innate immunity of host. To further understand the mechanisms by which BVDV overcomes the host cell innate immune response and provide more clues for further understanding the BVDV-host interaction, in this descriptive study, we conducted a investigation of differentially expressed genes (DEGs) of the host during BVDV infection by RNA-Seq analysis. Results Our analysis identified 1297, 1732, 3072, and 1877 DEGs in the comparison groups mock vs. MDBK cells infected with BVDV post 2 h (MBV2h), mock vs. MBV6h, mock vs. MBV12h, and mock vs. MBV24h, respectively. The reproducibility and repeatability of the results were validated by RT-qPCR. Enrichment analyses of GO annotations and KEGG pathways revealed the host DEGs that are potentially induced by BVDV infection and may participate in BVDV-host interactions. Protein-protein interaction (PPI) network analyses identified the potential interactions among the DEGs. Our findings suggested that BVDV infection induced the upregulation of genes involved in lipid metabolism. The expression of genes that have antiviral roles, including ISG15, Mx1, OSA1Y, were found to be downregulated and are thus potentially associated with the inhibition of host innate immune system during BVDV infection. The expression levels of F3, C1R, KNG1, CLU, C3, FB, SERPINA5, SERPINE1, C1S, F2RL2, and C2, which belong to the complement and coagulation signalling cascades, were downregulated during BVDV infection, which suggested that the complement system might play a crucial role during BVDV infection. Conclusion In this descriptive study, our findings revealed the changes in the host transcriptome expression profile during BVDV infection and suggested that BVDV-infection induced altering the host’s metabolic network, the inhibition of the expression of antiviral proteins and genes within the complement system might be contributed to BVDV proliferation. The above findings provided unique insights for further studies on the mechanisms underlying BVDV-host interactions.

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Quantification of economic losses consecutive to infection of a dairy herd with bovine viral diarrhoea virus

Preventive Veterinary Medicine ◽

10.1016/j.prevetmed.2005.08.018 ◽

2005 ◽

Vol 72 (1-2) ◽

pp. 177-181 ◽

Cited By ~ 27

Author(s):

Christine Fourichon ◽

François Beaudeau ◽

Nathalie Bareille ◽

Henri Seegers

Keyword(s):

Dairy Herd ◽

Bovine Viral Diarrhoea Virus ◽

Economic Losses ◽

Bovine Viral Diarrhoea ◽

Diarrhoea Virus

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Seroprevalence of bovine viral diarrhoea virus in Hungary — situation before launching an eradication campaign

Acta Veterinaria Hungarica ◽

10.1556/avet.2015.023 ◽

2015 ◽

Vol 63 (2) ◽

pp. 255-263 ◽

Cited By ~ 2

Author(s):

Csaba Kővágó ◽

Petra Forgách ◽

Ágnes Szabára ◽

Míra Mándoki ◽

Ákos Hornyák ◽

...

Keyword(s):

Bovine Viral Diarrhoea Virus ◽

Viral Disease ◽

Economic Losses ◽

Bovine Viral Diarrhoea ◽

Eradication Programme ◽

Diarrhoea Virus ◽

Eradication Campaign ◽

Monitoring Survey ◽

Cattle Herds ◽

Near Future

Bovine viral diarrhoea (BVD) is a viral disease appearing in various forms and causing high economic losses in the cattle stocks of Hungary. The aim of the present study was to determine the prevalence of bovine viral diarrhoea virus (BVDV) in Hungary through a monitoring survey carried out on samples collected in cattle-keeping units throughout the country. Since no such survey had been carried out in Hungary during the last thirty years, our study may serve as a basis for later monitoring investigations aimed at following the progress of an expected eradication campaign of BVD. The tests were carried out using an ELISA method, on a total of 1200 blood samples submitted from 54 cattle herds. The herds had not been vaccinated against BVDV before the sampling. Out of the 1200 samples, 521 proved to be positive (43.4%), 40 gave doubtful result (3.3%) and 639 were negative (53.3%). In some stocks the samples were collected from cows having completed several lactation periods, and therefore the seronegativity indicates the BVDV-free status of the given stock. Moreover, among the positive herds we found a few where the seropositivity rate was rather low (< 5%). According to the results of the survey, a rather high portion (about one third) of the cattle-keeping units of Hungary can be regarded as BVDV free, which ratio is much higher than had been expected on the basis of surveys carried out on a lower number of samples and in smaller regions of the country. Hence, the chances of an eradication campaign launched in the near future, or carried out parallel to the IBR eradication programme, are better than previously expected.

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Survey of nine abortifacient infectious agents in aborted bovine fetuses from dairy farms in Beijing, China, by PCR

Acta Veterinaria Hungarica ◽

10.1556/avet.2012.007 ◽

2012 ◽

Vol 60 (1) ◽

pp. 83-92 ◽

Cited By ~ 14

Author(s):

Na Yang ◽

Xia Cui ◽

Weifeng Qian ◽

Shanshan Yu ◽

Qun Liu

Keyword(s):

Neospora Caninum ◽

Bovine Viral Diarrhoea Virus ◽

Economic Losses ◽

Dairy Herds ◽

Infectious Agents ◽

Infectious Bovine Rhinotracheitis ◽

Diarrhoea Virus ◽

Bovine Fetuses ◽

Bovine Abortion ◽

Infectious Bovine Rhinotracheitis Virus

Abortion in dairy cattle causes considerable economic losses to the dairy industry. Aborted fetuses and samples from the corresponding aborting dams from 12 dairy herds in Beijing were tested for 9 abortifacient infectious pathogens by PCR between 2008 and 2010. From a total of 80 abortion cases collected during this period, infectious agents were detected in 45 (56.3%) cases, 22 (48.9%) of which represented co-infections with two or three infectious agents. The detected pathogens included infectious bovine rhinotracheitis virus (36.3%) andNeospora caninum(31.3%), followed by bovine viral diarrhoea virus (7.5%),Brucella abortus(6.3%),Tritrichomonas foetus(5%) andToxoplasma gondii(1.3%).Campylobacter fetus, Coxiella burnetiiandChlamydophila psittaciwere not detected in any abortion case. Findings from this study indicated that infectious bovine rhinotracheitis virus andNeospora caninumwere the main potential causes of abortions in Beijing dairy herds, whereas the bacterial pathogens were not, in contrast to reports from other countries. This is the first study to test nine abortifacient infectious agents by PCR at the same time, and it is also the first time to report the involvement of a variety of infectious agents in bovine abortion cases in China.

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A novel astrovirus species in the gut of yaks with diarrhoea in the Qinghai–Tibetan Plateau, 2013

Journal of General Virology ◽

10.1099/jgv.0.000303 ◽

2015 ◽

Vol 96 (12) ◽

pp. 3672-3680 ◽

Cited By ~ 18

Author(s):

Xi Chen ◽

Bin Zhang ◽

Hua Yue ◽

Yong Wang ◽

Fang Zhou ◽

...

Keyword(s):

Tibetan Plateau ◽

Influenza A ◽

Clinical Symptoms ◽

Hepatitis Virus ◽

Bovine Viral Diarrhoea Virus ◽

Hepatitis E ◽

Economic Losses ◽

Common Disease ◽

Diarrhoea Virus ◽

Viral Communities

The yak (Bos grunniens) is an iconic symbol in the high-altitude region of the Qinghai–Tibetan Plateau. Diarrhoea is a common disease in yaks, resulting in major economic losses. To investigate the diversity of viral species, we reported the metagenomics-derived virome in a pooled faecal sample of 20 diarrhoeic yaks. The nine viruses found in the pooled diarrhoeic samples, in order of abundance of nucleic acid sequence, were influenza A virus, bovine viral diarrhoea virus (BVDV), rotavirus, ungulate tetraparvovirus 1 (bovine hokovirus), astrovirus (AstV), bovine enterovirus, hepatitis E virus, kobuvirus and woodchuck hepatitis virus. Compared with healthy yaks, only AstV had a significantly higher prevalence rate in diarrhoeal samples, indicating a correlation with the clinical symptoms of diarrhoea in yaks. To further investigate the molecular characterization of yak AstV, a near-full genome was obtained from a diarrhoeic sample. It was 6243 bp in length and shared 46.4–66.2 % similarity with other related bovine AstVs from faeces. Phylogenetic analysis of the genome demonstrated that the yak AstV fell within the bovine AstVs cluster, but was located in a unique lineage, suggesting a novel AstV species was identified in yaks. Interestingly, the ORF2 region of yak AstV had closer similarity and genetically relationship with deer AstV strain CcAstV-2 than that of the bovine AstVs. Further analysis showed that one possible interspecies recombination event occurred in ORF2. In summary, this study expanded our understanding of the viral communities of diarrhoeal yaks and identified a novel AstV that was associated with diarrhoea in yaks.

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BVDFree England data analysis: descriptive analysis of national bovine viral diarrhoea test data in England.

10.31220/agrirxiv.2021.00095 ◽

2021 ◽

Author(s):

Naomi S. Prosser ◽

Edward M. Hill ◽

Derek Armstrong ◽

Lorna Gow ◽

Michael J. Tildesley ◽

...

Keyword(s):

Descriptive Analysis ◽

Bovine Viral Diarrhoea Virus ◽

Positive Test ◽

Economic Losses ◽

Dairy Herds ◽

Test Results ◽

Bovine Viral Diarrhoea ◽

Clear Trend ◽

Diarrhoea Virus ◽

Antigen Testing

Abstract Background: Bovine viral diarrhoea virus (BVDV) causes substantial economic losses to cattle herds; however, control and eradication can be achieved by identifying and removing persistently infected cattle. Each UK nation has separate control programmes. The English scheme, BVDFree, started in 2016 and is voluntary. Methods: We analysed the test results submitted to BVDFree from 5,847 herds from 2016 to 2020. Results: In 2020, 13.5% of beef breeder herds and 20.0% of dairy herds had at least one positive test result. Though lower than in previous years, there was no clear trend in the proportion of positive tests over time. In antigen testing herds, 1.5% of tests from antigen positive herds were positive, which was 0.4% of tests from all antigen testing herds. Dairy herds and larger herds were more likely to join BVDFree and dairy herds were also more likely to antigen test than beef breeder herds. Larger herds, herds that used individual antigen testing and herds that had BVD positive test results were more likely to continue submitting tests to BVDFree. Conclusions: The findings provide a benchmark for the status of BVD control in England; continued analysis of test results will be important to assess progress towards eradication.

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Cross-Reactivity Antibody Response after Vaccination with Modified Live and Killed Bovine Viral Diarrhoea Virus (BVD) Vaccines

Vaccines ◽

10.3390/vaccines8030374 ◽

2020 ◽

Vol 8 (3) ◽

pp. 374

Author(s):

Enrica Sozzi ◽

Cecilia Righi ◽

Massimo Boldini ◽

Moira Bazzucchi ◽

Giulia Pezzoni ◽

...

Keyword(s):

Statistical Analysis ◽

Clinical Manifestations ◽

Bovine Viral Diarrhoea Virus ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Bovine Viral Diarrhoea ◽

Diarrhoea Virus ◽

Wide Range ◽

Cross Immunity

Pestivirus A or bovine viral diarrhoea virus (BVDV) type 1 is responsible for cosmopolitan diseases affecting cattle and other ruminants, presenting a wide range of clinical manifestations, with relevant impact on zootechnic production. The objective of the present study was to verify whether animals immunised with four commercial vaccines also developed a protective humoral immunity against other viral subgenotypes than those contained in each vaccine. Four groups of 25 bovines each were formed and vaccinated according to the manufacturer’s instructions of the commercial vaccines. On sera collected 28 days after the last vaccination, virus neutralisation tests (VNT) were performed using homologous and heterologous viruses and enzyme-linked immunosorbent assay (ELISA) methods. Finally, the VNT results were comparatively evaluated through a statistical analysis. Serological results highlighted that, although with a different degree of efficiency, the four vaccines resulted in not developing a solid antibody-mediated cross-immunity against all the strains used.

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