Border Disease Research Articles

Molecular characterization of border disease virus strain Aveyron

For the pestivirus border disease virus (BDV) at least seven major genotypes have been described (BDV-1–BDV-7). So far, complete genomic sequences have been reported for four BDV genotypes (BDV-1–BDV-4). In this study we report the entire genomic sequence of the noncytopathogenic (ncp) BDV-5 reference strain Aveyron. The viral genome encompasses 12,284 nucleotides (nt) and contains one large open reading frame (11,700nt) flanked by a 370 nt long 5′-untranslated region (UTR) and a 214nt long 3′-UTR. The genome organization as well as the lengths of the viral polyprotein (3899 amino acids) and the 5′-UTR are very similar to the ones of other BDV strains, while the 3′-UTR of BDV Aveyron is considerably shorter when compared to other BDV strains. Comparative analysis of complete coding sequences revealed that BDV Aveyron shares nucleotide sequence identities of 76.9% to 79.0% with the other BDV strains, and less than 72% identity with other pestiviruses. In contrast to other BDV strains, a unique insertion of four amino acids (KAPD) of unknown origin is present in the C-terminal part of the viral autoprotease NS2 encoded by BDV Aveyron. Immunoblot analysis revealed that infection of cells with the ncp BDV strain Aveyron comprising this unique insertion in NS2 resulted in the expression of high amounts of NS3 and thereby showed that BDV Aveyron significantly differs from other ncp BDV strains in terms of NS2-3 processing and production of NS3.

Identification and Epidemiology of a Rare HoBi-Like Pestivirus Strain in Bangladesh

The genus pestivirus of the family flaviviridae consists of four recognized species: bovine viral diarrhoea virus 1 (BVDV-1), bovine viral diarrhoea virus 2 (BVDV-2), classical swine fever virus and border disease virus. A new putative pestivirus species tentatively named as either 'HoBi-like pestivirus' or BVDV-3 has recently been identified in Brazil, Italy and Thailand. Despite reports of serological evidence of BVDV in Bangladesh, the types of the virus circulating in cattle have not been identified. We conducted surveillance in cattle from May 2009 to August 2010 in three government veterinary hospitals to characterize BVDV in cattle of Bangladesh. We tested serum for BVDV using an antigen-capture ELISA. Of 638 cattle samples, 3% (16/638) tested positive for BVDV antigen. The ELISA-positive samples were selected for further molecular detection and characterization of BVDV. Molecular analysis of the partial 5' untranslated region (UTR) nucleotide sequences of BVDV-positive samples identified the rare HoBi-like pestivirus or BVDV-3 virus circulating in cattle of Bangladesh. The identification of this rare HoBi-like pestivirus or BVDV-3 strain in Bangladesh warrants further surveillance to evaluate its impact on livestock production.

Border disease in persistently infected calves: radiological and pathological findings

Veterinary RecordVolume 174, Issue 7 p. 170-170 Research Border disease in persistently infected calves: radiological and pathological findings S. Frei med. vet., S. Frei med. vet. Department of Farm Animals,...

Pestiviruses.

Pestiviruses cause economically important diseases among domestic ruminants and pigs, but they may also infect a wide spectrum of wild species of even-toed ungulates (Artiodactyla). Bovine viral diarrhea virus (BVDV) and Border disease virus of sheep infect their hosts either transiently or persistently. Cellular and humoral immunotolerance to the infecting strain is a unique feature of persistent infection (PI) by ruminant pestiviruses. Persistence, caused by transplacental infection early in fetal development, depends on virally encoded interferon antagonists that inactivate the host's innate immune response to the virus without globally interfering with its function against other viruses. At epidemiological equilibrium, approximately 1-2% of animals are PI. Successful BVDV control programs show that removal of PI animals results in viral extinction in the host population. The nucleotide sequences of ruminant pestiviruses change little during persistent infection. Nevertheless, they display large heterogeneity, pointing to a long history of virus-host coevolution in which avirulent strains are more successful.

Border disease virus: time to take more notice?

PESTIVIRUSES are the cause of classical swine fever (CSF), bovine viral diarrhoea (BVD) and border disease in sheep. CSF has, for decades, been listed as an OIE notifiable disease, and...

Complete Genome Sequence of Border Disease Virus Genotype 3 Strain Gifhorn

The complete genome sequence of the genotype 3 border disease virus strain Gifhorn has been determined; this strain was originally isolated from pigs. This represents the consensus sequence for the virus used to produce the bacterial artificial chromosome (BAC) cDNA clone pBeloGif3, which yields a virus that is severely attenuated in cell culture.

Comparative Investigation of Border Disease Virus Infection in Sheep Flocks with Abortion Problems in Konya Province

The aim of the present study was to determine the serological and virological status of animals persistently infected (PI) with border disease virus (BDV), with focus on the prevalence of pestiviruses in sheep and lambs. This study is the first to our knowledge, to investigate the role of viral infections in abortions in the sheep population of Konya province. The prevalence of antibodies against BDV was as follows: sheep, 79%; lambs, 43.4%; and rams, 6%. Of 1000 leukocyte (sheep) samples examined with a direct ELISA, 11 (1.1%) (first sampling) were antibody-positive. Three sheep were determined to be PI and were sacrificed. Of 1011 sheep leukocyte samples, 14 were examined using a direct immunoperoxidase (IP) assay for BDV antigen, and 11 of 327 (3.36%) tissue samples were positive. The BDV genome was detected in 14 of 63 (22.2%) sheep leukocyte samples and 11 of 327 (3.36%) tissue samples by one-step RT-PCR. The BDV genome could not be detected in any vaginal swab samples. The sensitivity and specificity rates between direct ELISA and direct IP were respectively 100% and 98.8% and the values were, respectively, 78.57% and 98.6% between direct ELISA and one-step RT-PCR and 100% and 97.5% between one-step RT-PCR and direct IP. In conclusion it was determinate that BDV has an important role as an etiologic agent in abortion causes in sheep population in Konya.

Molecular and serological investigation of border disease virus infection in sheep in the Kars District of Turkey

This study is a serological and virological examination of the border disease virus (BDV) in sheep at 1–5 years of age from private small scale production units of less than 20 sheep per unit, in the Kars District of Turkey. For this purpose, blood sera from 460 sheep were tested for antibodies against BDV using a commercial enzyme-linked immunosorbent assay (ELISA). Since BDV causes persistent infection, antigen-ELISA was also performed for this agent. Seropositivity rate was detected to be 74.57%. In addition, the BDV antigen was detected in one sample of seronegative sera (0.85%). Reverse transcription polymerase chain reaction (RT-PCR) technique was used to determine the presence of pestivirus nucleic acid by using 5’UTR primer pair. Pestivirus nucleic acid was found in 2 of 117 seronegative samples (1.71%) by RT-PCR. The results suggest that the infection was spreading in private small scale production units. Furthermore, recommendations for the control of BDV infection are presented. This study is the first molecular and serological study to determine viroprevalence and seroprevalence of BDV infection in sheep in the Kars District of Turkey.

First report on seroprevalence of bluetongue, border disease and peste des petits ruminants virus infections in sheep in Kyrgyzstan

In this study, the presence of antibodies against Bluetongue Virus (BTV), Border Disease Virus (BDV) and Peste des Petits Ruminants virus (PPRV), were evaluated for the first time in Kyrgyzstan. A total of 655 serum samples were collected from healthy sheep (Jaydara breed) from different regions of Kyrgyzstan (144 from Issik Gol region, 208 from Narin region, 189 from Talas region and 114 from Cuy region). Commercially available competitive ELISA kits were used to detect antibodies against tested samples. Seroprevalence was found to be 36.94%, 7.32% and 35.11% against BTV, BDV and PPRV infections, respectively. Significant differences in antibody prevalences were found among both BTV-BDV and BDV-PPRV groups (P< 0.001) only. This is the first report on seroprevalence of viral infections for BTV, BDV and PPRV in the Jaydara breed of sheep within Kyrgyzstan.

Npro of Bungowannah virus exhibits the same antagonistic function in the IFN induction pathway than that of other classical pestiviruses

Bungowannah virus is the most divergent atypical pestivirus that had been detected up to now, and does not fit into any of the four approved species: Bovine viral diarrhea virus type 1 (BVDV-1) and type 2 (BVDV-2), Classical swine fever virus (CSFV) and Border disease virus (BDV). However, the presence of Npro and Erns coding regions, which are unique to pestiviruses, provides clear evidence of a pestivirus. Nevertheless, the amino acid identity of Bungowannah virus Npro and BVDV-1 Npro (strain CP7) is only 51.5%. By using a BVDV-1 backbone, a novel chimeric construct was generated, in which the genomic region encoding the non-structural protein Npro was replaced by that of Bungowannah virus (CP7_Npro-Bungo). In vitro studies of CP7_Npro-Bungo revealed autonomous replication with the same efficacy as the BVDV backbone CP7 and infectious high-titer virus could be collected. In order to compare the ability of interferon (IFN) suppression, two reporter gene assays, specific for type-I IFN, were carried out. In virus-infected cells, no significant difference in blocking of IFN expression between the parental virus CP7, Bungowannah virus and the chimeric construct CP7_Npro-Bungo could be detected. In contrast, an Npro deletion mutant showed an impaired replication in bovine cells and a marked type-I IFN response.Taken together, our findings reveal the compatibility of non-structural protein Npro of atypical Bungowannah virus with a BVDV type 1 backbone and its characteristic feature as an inhibitor of type-I IFN induction with an inhibitor-activity comparable to other pestiviruses.

Detection of border disease virus (BDV) genotype 3 in Italian goat herds

In January 2011, cases of abortion, stillbirth and weak live kids were reported in two goat herds in northern Italy. Samples from 18 kids found dead, 12 fetuses, and two stillborn kids were analyzed for pestivirus antigen using an ELISA kit and a border disease virus (BDV)-specific RT-PCR. Positive results were obtained in six kids and one fetus. Phylogenetic analysis based on 225bp of the 5′UTR fragment of the BDV genome from positive samples showed that the goats were infected with BDV genotype 3. Serum and blood samples collected from all animals in both herds were analyzed using competitive ELISA to detect p80 antibodies and RT-PCR to detect viraemia.Pestivirus antibodies were detected in 61/67 goats in herd A and in 38/169 in herd B. A persistently infected (PI) goat was found in herd A. The PI animal was submitted to the laboratory for BDV diagnosis with Ag-ELISA, viral isolation, and nested RT-PCR on tissue samples from the spleen, kidney, brain, liver, lung, ileocaecal valve, mesenteric lymph nodes, and skin. All of the tests were positive for BDV in each of the tissues analyzed. The BDV sequence of the PI was identical to BDV sequences found in other positive animals. This is the first description of a BDV PI goat and the first evidence of BDV genotype 3 circulation in Italy. The study raises questions about the real impact this virus has on breeding goats.

Identification of a porcine pestivirus as a border disease virus from naturally infected pigs in Spain

Border disease virus (BDV), together with bovine viral diarrhoea virus 1 (BVDV-1), BVDV-2 and classical swine fever virus (CSFV), is classified in the genus Pestivirus within the family Flaviviridae ....

Sheep persistently infected with Border disease readily transmit virus to calves seronegative to BVD virus

Bovine viral diarrhea- and Border disease viruses of sheep belong to the highly diverse genus pestivirus of the Flaviviridae. Ruminant pestiviruses may infect a wide range of domestic and wild cloven-hooved mammals (artiodactyla). Due to its economic importance, programs to eradicate bovine viral diarrhea are a high priority in the cattle industry. By contrast, Border disease is not a target of eradication, although the Border disease virus is known to be capable of also infecting cattle. In this work, we compared single dose experimental inoculation of calves with Border disease virus with co-mingling of calves with sheep persistently infected with this virus. As indicated by seroconversion, infection was achieved only in one out of seven calves with a dose of Border disease virus that was previously shown to be successful in calves inoculated with BVD virus. By contrast, all calves kept together with persistently infected sheep readily became infected with Border disease virus. The ease of viral transmission from sheep to cattle and the antigenic similarity of bovine and ovine pestiviruses may become a problem for demonstrating freedom of BVD by serology in the cattle population.

Serosurvey on Schmallenberg Virus and Selected Ovine Reproductive Pathogens in Culled Ewes From Southern Spain

After the first case of Schmallenberg virus (SBV) was reported in southern Spain (March 2012), a retrospective serological study was carried out in extensive sheep flocks from nearby areas to assess the history of exposure to SBV and other selected ovine reproductive pathogens (Chlamydophila abortus, Coxiella burnetii, Border Disease virus 'BDV', Toxoplasma gondii and Neospora caninum). Secondly, the presence of antibodies was investigated in meat juice samples against selected pathogens to validate their use in serosurveys in sheep. A total of 209 Merina and cross-bred culled ewes belonging to 12 outdoor flocks managed in extensive breeding systems were sampled. Serum and meat juice samples were collected at the slaughterhouse and analysed using commercial ELISA kits. Chlamydophila abortus (62.68%, CI95 56.13-69.23) and Toxoplasma gondii (57.42%, CI95 50.72-64.12) were the most prevalent pathogens. The seroprevalence of BDV (16.27%, CI95 11.27-21.27) and Coxiella burnetii (13.88%, CI95 9.2-18.56) was moderate, and only 4 of 209 animals (1.91%, CI95 1.82-2.96) presented specific antibodies against Neospora caninum or SBV. All the examined ovine flocks were seropositive to three or more pathogens. The highest percentage of seropositive animals was detected for T.gondii-C.abortus coseropositive (25.36%) culled ewes. The concordance between serum and meat juice samples was moderate for T.gondii (κ=0.419) and BDV (κ=0.568), and fair for C.abortus (κ=0.311). Our results show evidence of circulation of SBV from summer 2011 in southern Spain. Furthermore, C.abortus and T.gondii were the most prevalent pathogens associated with sheep in outdoor rearing systems. Finally, these preliminary results point to meat juice samples as a potential biological sample for serosurveys studies on sheep.

Genome Sequence of Border Disease Virus Strain JSLS12-01, Isolated from Sheep in China

Border disease virus (BDV) is a recognized virus in the genus Pestivirus and causes border disease (BD) in sheep and goats. Here, a novel BDV strain, JSLS12-01, was identified from sheep in Jiangsu Province, China. The complete coding sequence (CDS) was finished, which provides a better understanding of the molecular evolution of BDV isolates.

Natural border disease virus infection in feedlot lambs

Border disease is caused by border disease virus (BDV, a pestivirus from the family Flaviviridae ) infection in sheep and goats (Vantsis and others 1976). BDV infection causes sizeable economic...

Selected acute phase proteins, oxidative stress biomarkers, and antioxidants in aborting and non-aborting goats infected with Border disease virus

Abstract Goats were grouped into three health categories based on the clinically and serologically proven cases: infected nonaborting (group A) (n = 10), infected aborting (group B) (n = 10), and non-infected (group C) (n = 10). In all groups, blood samples were collected and analysed for malondialdehyde (MDA) and nitric oxide (NO) levels in plasma, haptoglobin (Hp) and amyloid A (SAA) in serum, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in erythrocytes. A statistically significant decrease in GSH-Px and SOD activities and increase in MDA, NO, Hp, and SAA levels were observed in groups A and B compared to group C. Additionally, MDA, NO, Hp, and SAA levels of the aborting goats were significantly higher, whereas SOD levels were lower than those of the non-aborting groups.

A survey on the status of the border disease virus infection in sheep with reproductive failure using cell culture and polymerase chain reaction (PCR) methods in Tabriz, Iran

The most important causal agent of border disease (BD), border disease virus (BDV), is a Pestivirus in the family Flaviviridae. In attention to the lack of molecular documented data on the prevalence of BDV in Iran, especially in East Azerbaijan Province, northwest of Iran, this research was designed to determine the prevalence of BDV in suspected ewes that have an antecedent of reproductive failure. Eighty-eight suspected ewes in the breed of Ghezel, Mogan, and mix (Ghezel × Mogan) in five various districts of East Azerbaijan Province (Azershahr, Lyqvan, Osku, Sofian, and Varzqan) were selected. Razi bovine kidney (RBK) cell lines were grown, and the buffy coat layer was separated and inoculated to the monolayer cell culture. All cell cultures were inspected for cytopathic effects after 5–7 days. BDV genomes were being checked using nested reverse transcription polymerase chain reaction method. Ten samples (10/88, 11.36 %) were positive for the genome of BDV. The prevalence of BDV infection was found to vary between different districts. The highest percentage of infected sheep was in animals at the 3–4.5-year-old range (15.38 %). There was no statistically significant difference in the prevalence among different age categories. The highest BDV infection rate was observed in full blood ewes in Mogan and Ghezel. Cytopathic effects of the virus in the culture on RBK cell line were not observed at all. This study proved that the infection of BDV is present in sheep in the East Azerbaijan, northwest of Iran, and cause some reproductive failure in the flocks. The survey is the first molecular evidence of the occurrence of the disease in the country.

Preliminary mapping of non-conserved epitopes on envelope glycoprotein E2 of Bovine viral diarrhea virus type 1 and 2

Bovine viral diarrhea virus (BVDV) belongs together with Classical swine fever virus (CSFV) and Border disease virus (BDV) to the genus Pestivirus in the Flaviviridae family. BVDV has been subdivided into two different species, BVDV1 and BVDV2 based on phylogenetic analysis. Subsequent characterization of both strains revealed major antigenic differences. Because the envelope glycoprotein E2 is the most immunodominant protein for all pestiviruses, the present study focused on epitope mapping by constructing chimeric BVDV type 1 and 2 E2 genes in expression plasmids. These plasmids with chimeric E2-genes were transfected in SK6 cells and transient expression was studied by immunostaining with a panel of MAbs specific for E2 of BVDV1 or BVDV2, resulting in the localization of type-specific antigenic domains at similar regions. These results indicate that E2 glycoproteins of both BVDV types exhibit a comparable antigenic structure, but with type specific epitopes. In addition, the antigenic resemblance with envelope glycoprotein E2 of Classical swine fever virus is discussed.

Isolation and molecular characterisation of a pestivirus from goats in Egypt

Nine fetuses and neonates from sheep and goats in Egypt were screened for pestiviruses using immunohistochemistry (IHC), virus isolation, and reverse transcription-polymerase chain reaction (RT-PCR). Two goat kids with typical border disease (BD) were positive for pestivirus infection by immunohistochemistry (IHC) using polyclonal anti-BDV serum but not when four different monoclonal antibodies (MAbs) were used. On inoculation in MDBK cells, a cytopathic bovine viral diarrhoea virus (BVDV) was isolated from one of the two kids. PCR amplification followed by sequencing of the 5'-UTR region confirmed it as BVDV subtype 1b. Although the circulating virus in Egypt is considered to be BVDV 1a, this report confirms the existence of BVDV 1b in addition to BVDV 1a. To our knowledge, this is the first report of isolation of a pestivirus from goats in Egypt and is probably the second report worldwide of a goat kid showing central nervous signs associated with border disease.