| bone marrow depletion with haemorrhagic diathesis in calves in germany: characterization of the disease and preliminary investigations on its aetiology. | since 2007 a new fatal haemorrhagic diathesis in calves has been observed in all areas of germany. analysis of 56 cases submitted for necropsy allowed its characterization. calves fell ill within the first month of life independent of breed and sex. only single or a few animals per herd were affected. petechial and ecchymotic haemorrhages in many organs and tissues, particularly in skin, subcutis and gastrointestinal tract, were major findings in all animals. microscopically a severe depletion o ... | 2010 | 20135908 |
| viral distribution and lesions in kunming mice experimentally infected with porcine circovirus type 2b. | the viral distribution and lesions in kunming mice experimentally infected with porcine circovirus type 2b (pcv-2b) were investigated. seventy special pathogen free mice were divided into 2 groups with 35 mice in each group. the test group (tg) was infected with pcv-2b, the control group (cg) was inoculated with sterile cell cultures. five mice in each group were sacrificed at 3, 7, 14, 21, 28, 35 and 42 dpi (day post infection), respectively. necropsies were performed on all mice and tissues we ... | 2011 | 21287271 |
| detection of the assembly and disassembly of pcv2b virus-like particles using fluorescence spectroscopy analysis. | monitoring the assembly and disassembly of virus-like particles (vlps) is important in developing effective vlp-based vaccines. we tried to establish a simple and rapid method to evaluate the status of vlp assembly using fluorescence spectroscopic analysis (fsa) while developing a vlp-based vaccine against porcine circovirus type 2b (pcv2b). we synthesized the gene coding for pcv2b capsid protein (cp). the cp was expressed in escherichia coli in a soluble form, dialyzed into three different buff ... | 2015 | 26783743 |
| effect of temperature on the survival of porcine circovirus type 2b in fresh pork. | porcine circovirus type 2b (pcv2b) causes pcv-associated disease in pigs. this study was conducted to investigate the effect of temperature on the survival of pcv2b in fresh pork. several pieces of longissimus dorsi muscle were injected with 100 μl of a suspension containing 10(5.2) tcid50 (50% tissue culture infective doses) of the virus. virus-inoculated pieces of pork were stored at 25 °c, 4 °c and -20 °c and tested for the presence of infectious virus after different times of storage. pcv2b ... | 2013 | 23683855 |
| effect of a major quantitative trait locus for porcine reproductive and respiratory syndrome (prrs) resistance on response to coinfection with prrs virus and porcine circovirus type 2b (pcv2b) in commercial pigs, with or without prior vaccination for prrs. | a major qtl for host response to porcine reproductive and respiratory syndrome (prrs) virus (prrsv) infection was identified in a previous study. single nucleotide polymorphism wur10000125 (wur), which is in complete linkage disequilibrium with the putative causative mutation, can be used as a tag snp for the qtl. however, the effect of wur following prrs vaccination and/or coinfection with other pathogens is not known. therefore, objectives of this study were to estimate the effect of wur on ho ... | 2017 | 28380604 |
| versatile carboxyl-terminus of capsid protein of porcine circovirus type 2 were recognized by monoclonal antibodies with pluripotency of binding. | we designed the peptide (c3) mimetic carboxyl-terminus (cterminus) of capsid protein of porcine circovirus type 2b (pcv2b-1a/1b) inducing humoral immunity and generating hybridomas. the positive reactivity of the mabs to pcv2 capsid protein was demonstrated by western blot assay. those mabs also showed positive signals on pcv2b infected swine lymphocytes by indirect immunofluorescence staining. the mab 1h3 bound to three minimal linear epitopes (p62, dpplnp; p67, dpplnpk; p73, lkdpplkp), which w ... | 2017 | 28219820 |
| replacing the decoy epitope of pcv2b capsid protein with a protective epitope enhances efficacy of pcv2b vaccine. | microbial pathogens may evolve decoy epitopes to evade host immune responses. in recent years, a decoy epitope has been identified in the capsid protein (cp) of porcine circovirus type 2b (pcv2b) to divert the immune response away from protective epitopes in pigs. to avoid the decoy effect, we designed and produced a recombinant pcv2b cp (δcp) by replacing the decoy epitope with a neutralizing b cell epitope derived from cp and tested the ability of δcp to induce protective antibody responses in ... | 2016 | 27817956 |
| vertical transmission of pcv2b to fetuses in sows intramuscularly infected with pcv2b. | in order to investigate whether pcv2b can be transmitted across the placenta in sows thereby causing vertical infection of fetuses, six sows in 75 day of pregnancy were either intramuscularly inoculated with a pcv2b culture supernatant (n = 4) or mock infected with cell culture supernatant (n = 2). at parturition, 3 newborn piglets from each litter were randomly selected and euthanatized prior to suckling. samples of the mesenteric lymph nodes, spleens, kidneys, hearts and lungs were collected f ... | 2016 | 27760027 |
| phylodynamic analysis of porcine circovirus type 2: methodological approach and datasets. | since its first description, pcv2 has emerged as one of the most economically relevant diseases for the swine industry. despite the introduction of vaccines effective in controlling clinical syndromes, pcv2 spread was not prevented and some potential evidences of vaccine immuno escape have recently been reported ("complete genome sequence of a novel porcine circovirus type 2b variant present in cases of vaccine failures in the united states" (xiao and halbur, 2012) [1], "genetic and antigenic ch ... | 2016 | 27508215 |
| comparative efficacy of experimental inactivated and live-attenuated chimeric porcine circovirus (pcv) 1-2b vaccines derived from pcv1 and pcv2b isolates originated in china. | porcine circovirus type-2b (pcv2b) is recognized as the etiological agent of the various clinical manifestations of porcine circovirus-associated disease (pcvad). previous studies have demonstrated effectiveness of chimeric pcv1-2 vaccines against pcv2b challenge. in this study, the efficacy of inactivated and live-attenuated (2 × 10(3.5) or 2 × 10(4.0) 50% tissue culture infective dose [tcid50] dose) chimeric pcv1-2b vaccines was compared side-by-side in conventional pigs. | 2015 | 26220290 |
| first identification of porcine circovirus type 2b mutant in pigs from uruguay. | porcine circovirus type 2 (pcv2) is a worldwide distributed virus and is considered an important emerging pathogen related to several distinct disease syndromes in pigs. pcv2 strains are classified into three genotypes: pcv2a, with five subtypes (2a-2e), pcv2b with three subtypes (1a-1c) and pcv2c, only found in denmark. recently, several reports suggested the circulation of newly emerging pcv2b mutants (mpcv2b) isolated from pigs with pcvad in cases of suspected vaccine failure. in this work, w ... | 2015 | 26004195 |
| detection of a new cluster of porcine circovirus type 2b strains in domestic pigs in germany. | pcv2 can be divided into three different genotypes: pcv2a, pcv2b and pcv2c. since 2004/2005 pcv2b has become the predominant genotype in the domestic pig population worldwide. in the years 2010 and 2012 pcv2b mutant strains (mpcv2), classified as pcv2b-1c strains, were detected in porcine circovirus diseases (pcvd) affected pigs in china and the united states, respectively. within one year (april 2013-april 2014) newly emerging mpcv2 strains were isolated in seven german pig farms routinely vacc ... | 2015 | 25669598 |
| an emerging porcine circovirus type 2b mutant (mpcv2b) originally known as pcv2d. | | 2015 | 25467993 |
| genetic and antigenic characterization of a newly emerging porcine circovirus type 2b mutant first isolated in cases of vaccine failure in korea. | this study describes the genetic and antigenic characterization of a newly emerging porcine circovirus type 2b (pcv2b) mutant first isolated in cases of vaccine failure in korea. the full genome of the pcv2b isolates (snuvr130689 and snuvr140004) is 1,767 base pairs (bp) in length. the size of orf1 is 945 bp, encoding a protein of 314 amino acids (aa), and the size of orf2 is 705 bp, encoding a protein of 234 aa, which is 1 aa longer than that of the common pcv2 (233 aa). korean pcv2b mutant str ... | 2014 | 25034669 |
| transmission of porcine circovirus type 2b (pcv2b) in kunming mice. | to investigate porcine circovirus type 2b (pcv2b) transmission by contact and vertical infection in kunming mice (an outbred mouse stock deriving from swiss albino mice with a high ratio of gene heterozygosis), four mice in cage 6 were inoculated with pcv2b and 25 mice without any treatment were placed into cages 1 to 5 (five mice in each cage). seven days after being infected, the pcv2-binoculated mice were co-mingled with non-inoculated mice from cages 1 to 5 successively at 7, 14, 21, 28 and ... | 2013 | 23661391 |
| attenuation of porcine circovirus type-2b by replacement with the rep gene of porcine circovirus type-1. | porcine circovirus type-2 (pcv2) is the primary causative agent of porcine circovirus-associated diseases and has 4 main orfs, orf1 (rep gene), orf2 (cap gene), orf3 within orf1, and orf4, which is overlapped with orf3, and 1 origin (ori) of replication located between orf1 and orf2. the chimeric pcv1-2, containing the pcv2 capsid, pcv1 rep, and ori genes, is attenuated in pigs. in order to verify the role of the rep gene or ori in the virulence of pcv2, 3 chimeric viruses [pcv2b-ori1 (pcv1 ori ... | 2013 | 23454919 |
| complete genome sequence of a novel porcine circovirus type 2b variant present in cases of vaccine failures in the united states. | two genomes of a new porcine circovirus type 2 (pcv2) strain associated with cases of perceived failure of pcv2 vaccination were sequenced and analyzed. based on the genome, this is the first report of this mutant of pcv2b in the united states. the genomic knowledge of this mutant pcv2b will improve understanding of the epidemiology of pcv and potentially inform the development of new and more effective vaccines for pcv2. | 2012 | 23087125 |
| germocyte lesions caused by porcine circovirus type 2b in kunming mice. | porcine circovirus type 2 (pcv2) has been known as a causative agent of reproductive failure in the sow. in the present study mouse model was used to investigate pcv2 infection. in order to investigate whether pcv2 can induce lesions of spermatocytes and oocytes, 6 male and 6 female mice were each inoculated intraperitoneally with pcv2b, and 3 male and 3 female mice mock-infected with cell culture supernatant served as controls. samples of testes and ovaries from pcv2b-inoculated and mock-infect ... | 2017 | 28525333 |
| high-level expression and immunogenicity of porcine circovirus type 2b capsid protein without nuclear localization signal expressed in hansenula polymorpha. | currently, porcine circovirus type 2b (pcv2b) is the dominant pcv2 genotype causing postweaning multisystemic wasting disease (pmws) in pigs worldwide. efforts have been made to develop various recombinant capsid proteins of pcv2b used in vaccines against pcv2b. however, the nuclear localization signal (nls) of pcv2b capsid protein (cp) was found to inhibit the expression of the whole length capsid protein in e.coli. here, we expressed a nls-deleted capsid protein (δcp) of pcv2b in hansenula pol ... | 2018 | 29225046 |
| genomic regions associated with host response to porcine reproductive and respiratory syndrome vaccination and co-infection in nursery pigs. | the wur1000125 (wur) single nucleotide polymorphism (snp) can be used as a genetic marker for host response to porcine reproductive and respiratory syndrome (prrs), prrs vaccination, and co-infection with porcine circovirus type 2b (pcv2b). objectives of this study were to identify genomic regions other than wur associated with host response to prrs vaccination and prrsv/pcv2b co-infection and regions with a different effect on host response to co-infection, depending on previous vaccination for ... | 2017 | 29132293 |
| novel chimeric porcine circovirus (pcv) with the capsid gene of the emerging pcv2b subtype cloned in the genomic backbone of the non-pathogenic pcv1 is attenuated in vivo and induces protective and cross-protective immunity against pcv2b and pcv2a subtypes in pigs. | porcine circovirus type-2b (pcv2b) is the primary global causative agent of porcine circovirus-associated disease (pcvad). in this study, we first constructed a novel chimeric virus (pcv1-2b) with the pcv2b capsid gene cloned into the backbone of non-pathogenic pcv1. a pathogenicity study conducted in caesarean-derived colostrum-deprived pigs showed that pigs inoculated with pcv1-2b (n=10) had decreased lymphoid lesions and significantly lower viral load at 21 dpi, and significantly lower viremi ... | 2010 | 21044670 |