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interaction of porcine circovirus type 2 and mycoplasma hyopneumoniae vaccines on dually infected pigs.the objective of this study was to determine the effects of porcine circovirus type 2 (pcv2) and mycoplasma hyopneumoniae vaccinations on disease severity in an experimental pcv2-m. hyopneumoniae dual challenge model. vaccine effectiveness was evaluated using microbiological (pcv2 viremia and m. hyopneumoniae nasal shedding), immunological (neutralizing antibodies and interferon-γ-secreting cells), and pathological (gross lung lesions, histopathologic pulmonary and lymphoid lesions, and the pres ...201424631087
global gene expression profiling of myeloid immune cell subsets in response to in vitro challenge with porcine circovirus 2b.compelling evidence suggests that the early interaction between porcine circovirus 2 (pcv-2) and the innate immune system is the key event in the pathogenesis of post-weaning multisystemic wasting syndrome (pmws). furthermore, pcv2 has been detected in bone-marrow samples, potentially enabling an easy spread and reservoir for the virus. to assess the gene-expression differences induced by an in-vitro pcv2b infection in different three different myeloid innate immune cell subsets generated from t ...201424618842
clinical, virological, immunological and pathological evaluation of four porcine circovirus type 2 vaccines.the objective of this study was to rigorously compare the efficacy of four porcine circovirus type 2 (pcv2) vaccines of varying antigen type and dose under experimental conditions based on well-defined clinical (average daily weight gain [adwg]), virological (evidence of viraemia), immunological (presence of pcv2-specific neutralising antibodies [na], interferon-γ-secreting cells [ifn-γ-scs], and cd3(+) and cd4(+) t cell subsets), and pathological (lymphoid lesion and pcv2 antigen score) criteri ...201424618398
enhanced porcine circovirus cap protein production by pichia pastoris with a fuzzy logic do control based methanol/sorbitol co-feeding induction strategy.porcine circovirus cap protein production by p. pastoris with strong aox promoter suffered with the problems with traditional pure methanol induction: (1) inefficient methanol metabolism; (2) extensive oxygen supply load; (3) difficulty in stable do control; (4) low protein titer. in this study, based on the difference of do change patterns in response to methanol and sorbitol additions, a novel fuzzy control system was proposed to automatically regulate the co-feeding rates of methanol and sorb ...201424613300
pigs naturally exposed to porcine circovirus type 2 (pcv2) generate antibody responses capable to neutralise pcv2 isolates of different genotypes and geographic origins.porcine circovirus type 2 (pcv2) is the essential infectious agent for pcv2-systemic disease (pcv2-sd, formerly known as postweaning multisystemic wasting syndrome) and other pathological conditions. recent studies indicated antigenic variability amongst different pcv2 isolates and suggested that single amino acid changes within the capsid protein determine differences in the level of neutralization by specific monoclonal antibodies. the objective of the present study was to examine the cross-re ...201424602200
origin of porcine circovirus type 2 (pcv2) from swine affected by pcv2-associated diseases in croatia.porcine circovirus type 2 (pcv2) causes some of the most significant economic losses in pig production. several multisystemic syndromes have been attributed to pcv2 infection, which are known as pcv2-associated diseases (pcvds). this study investigated the origin and evolution of pcv2 sequences in domestic pigs and wild boars affected by pcvds in croatia. viral sequences were recovered from three wild boars diagnosed with pcv2-systemic disease (pcv2-sd), 63 fetuses positive for pcv2 dna as deter ...201424591478
proteomics on porcine haptoglobin and igg/iga show protein species distribution and glycosylation pattern to remain similar in pcv2-sd infection.haptoglobin (hp) and immunoglobulins are plasma glycoproteins involved in the immune reaction of the organism after infection and/or inflammation. porcine circovirus type 2-systemic disease (pcv2-sd), formerly known as postweaning multisystemic wasting syndrome (pmws), is a globally spread pig disease of great economic impact. pcv2-sd affects the immunological system of pigs causing immunosuppression. the aim of this work was to characterize the hp protein species of healthy and pcv2-sd affected ...201424576640
porcine circovirus: a historical perspective.porcine circoviruses (pcvs) belong to the genus circovirus and the family circoviridae, and they are the smallest known viruses that replicate autonomously in mammalian cells. they are nonenveloped, and they have characteristic single-stranded, negative-sense, circular dna. two types of divergent pcvs are recognized: pcv1 and pcv2. about 20 years ago, pcv2 began to emerge as a major pathogen of swine around the world, leading to burgeoning knowledge about the virus and porcine circovirus-associa ...201424569612
utility of specific biomarkers to assess safety of swine manure for biofertilizing purposes.swine production is an important economic activity in brazil, and there is interest in the development of clean production mechanisms to support sustainable agro-industrial activities. the biomass derived from swine manure has good potential to be used as a biofertilizer due to its high nutrient concentration. however, the land application of manure should be based on safety parameters such as the presence of pathogens that can potentially infect animals and people. this study was designed to as ...201424565860
the application of a duplex reverse transcription real-time pcr for the surveillance of porcine reproductive and respiratory syndrome virus and porcine circovirus type 2.the porcine respiratory disease complex (prdc) is the most common disease in commercial pork production worldwide. porcine circovirus type 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv), the most important agents of prdc, usually co-infect in the same pigs. in order to survey the prevalence of pcv2 and prrsv in pigs of various ages, a duplex reverse transcription real-time pcr (drt-rpcr) was developed and applied in the present study. the drt-rpcr did not cross-react wi ...201424560782
reduction of spiked porcine circovirus during the manufacture of a vero cell-derived vaccine.porcine circovirus-1 (pcv1) was recently identified as a contaminant in live rotavirus vaccines, which was likely caused by contaminated porcine trypsin. the event triggered the development of new regulatory guidance on the use of porcine trypsin which shall ensure that cell lines and porcine trypsin in use are free from pcv1. in addition, manufacturing processes of biologicals other than live vaccines include virus clearance steps that may prevent and mitigate any potential virus contamination ...201424560672
identification of mycoplasma suis antigens and development of a multiplex microbead immunoassay.the aims of the current study were to identify mycoplasma suis antigens and develop a multiplex microbead immunoassay (mia). a m. suis-expression library was screened for immunogens using sera from infected pigs. based on bioinformatics, putative antigens were identified within positive inserts; gene fragments were expressed and purified as polyhistidine fusion proteins, and immunoreactivity was confirmed by western blot. selected antigens were used to develop a mia. sera from noninfected and in ...201424557752
first analysis of synonymous codon usage in porcine circovirus.porcine circovirus (pcv) is grouped into two types: pcv1 and pcv2. pcv1 is isolated from cultured cells and usually causes no clinical diseases in pigs. pcv2 is a pathogen of severe pig disease and a great threat to swine health and production. in our study, to investigate the codon usage bias of pcv, the genomic sequences of pcv1 and pcv2 were analyzed. the results showed that the codon usage bias of pcv was very low. an effective number of codons (enc) plot analysis indicated that mutational p ...201424557524
orf4-protein deficient pcv2 mutants enhance virus-induced apoptosis and show differential expression of mrnas in vitro.porcine circovirus type 2 (pcv2) is the essential infectious agent of pcv associated disease (pcvad). during previous in vitro studies, 11 rnas and four viral proteins have been detected in pcv2-infected cells. open reading frame (orf) 4 is 180bp in length and has been identified at the transcription and the translation level. it overlaps completely with orf3, which has a role in virus-induced apoptosis. in this study, start codon mutations (m1-pcv2) or in-frame termination mutations (m2-pcv2) w ...201424503223
occurrence and severity of lung lesions in slaughter pigs vaccinated against mycoplasma hyopneumoniae with different strategies.different vaccination strategies against mycoplasma hyopneumoniae have been adopted worldwide. reports from the field indicate varying levels of protection among currently available vaccines. the goal of the present study was to compare the efficacies of three widespread commercial vaccination strategies against m. hyopneumoniae under field conditions. 20 farms were included. 14 farms used different single dose vaccines (vaccine 1 [v1], 8 herds; vaccine 2 [v2], 6 herds); another 6 farms (v3) use ...201424485705
swine infectious agents in tayassu pecari and pecari tajacu tissue samples from brazil.peccaries and pigs, tayassuidae and suidae respectively, diverged approximately one million years ago from a common ancestor. because these families share some pathogens, peccaries can act as reservoirs of infectious pathogens for domestic and wild swine. we evaluated the presence of swine infectious agents in the spleen and lung tissues of white-lipped peccaries (wlp; tayassu pecari) and collared peccaries (cp; pecari tajacu) in brazil. samples from 10 adult cp and three wlp, which had been hun ...201424484498
effect of porcine circovirus type 2 (pcv2) vaccination on pcv2-viremic piglets after experimental pcv2 challenge.the objective of this study was to evaluate the effect of porcine circovirus type 2 (pcv2) vaccines on pcv2-viremic and -seropositive piglets born from naturally pcv2-infected sows against postnatal pcv2 challenge. the experimental design was aimed at mimicking commercial swine rearing conditions to evaluate the response of the pcv2 vaccine on pcv2-viremic and -seropositive piglets after experimental pcv2 challenge. pcv2a (or 2b)-viremic piglets received a pcv2 vaccine at 21 days of age followed ...201424484292
genetic characterization of porcine circovirus type 2 in the korean wild boar population.the porcine circovirus type 2 (pcv2) has reached very high levels in the pig population in south korea and throughout the world since it was first described in the late 1990s. in this study, we found that the prevalence of pcv2 in the korean wild boar population was 4.98% (91/1825). interestingly, 19 pcv2 orf2 sequences that could be completely sequenced showed that they belonged only to genotype pcv2b, subgroup 1a/b (n=16) and 1c (n=3). we suggest that sites potentially under positive selection ...201424480584
genomic analysis of the differential response to experimental infection with porcine circovirus 2b.porcine circovirus type 2 (pcv2) is the etiological agent of a group of associated diseases (pcvad) that affect production efficiency and can lead to mortality. using different crossbred lines of pigs, we analyzed host genetic variation of viral load, immune response and weight change following experimental infection with a pcv2b strain (n = 386). pigs expressed variation in the magnitude and initiation of viremia and immune response recorded weekly until 28 days post-infection. a higher viral l ...201424444103
whole-genome sequences of two strains of porcine circovirus 2 isolated from calves in germany.two new strains of porcine circovirus type 2 virus (pcv2), strains ha09 and ha10, were detected in calves in germany, and the complete genome of each virus has been sequenced and analyzed. phylogenetic analysis suggests that these strains belong to the pcv2b genotype cluster, a highly prevalent genotype found worldwide.201424407647
comparison of four commercial one-dose porcine circovirus type 2 (pcv2) vaccines administered to pigs challenged with pcv2 and porcine reproductive and respiratory syndrome virus at 17 weeks postvaccination to control porcine respiratory disease complex under korean field conditions.under korean field conditions, coinfection with porcine circovirus type 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv) is most commonly observed in porcine respiratory disease complex (prdc). despite the wide use of pcv2 vaccination, prdc remains a serious respiratory problem. thus, the objective of this study was to determine and compare the efficacy of 4 one-dose pcv2 vaccines on 3-week-old pigs with an experimental pcv2-prrsv challenge at 17 weeks postvaccination. re ...201424403524
a live-attenuated and an inactivated chimeric porcine circovirus (pcv)1-2 vaccine are both effective at inducing a humoral immune response and reducing pcv2 viremia and intrauterine infection in female swine of breeding age.the objective of this pilot study was to determine the efficacy of inactivated (1 or 2 dose) and live-attenuated chimeric porcine circovirus (pcv)1-2 vaccines in sows using the pcv2-spiked semen model. thirty-five sows were randomly divided into 6 groups: negative and positive controls, 1 dose inactivated pcv1-2 vaccine challenged (1-vac-pcv2), 2 dose inactivated pcv1-2 vaccine challenged (2-vac-pcv2), 1 dose live-attenuated pcv1-2 vaccine unchallenged (1-live-vac), and 1 dose live-attenuated pc ...201424396175
porcine circovirus type 2 decreases the infection and replication of attenuated classical swine fever virus in porcine alveolar macrophages.recently, it has been noted that porcine circovirus type 2 (pcv2) infection adversely affects the protective efficacy of lapinized philippines coronel (lpc) vaccine, an attenuated strain of classical swine fever virus (csfv), in pigs. in order to investigate the possible mechanisms of the pcv2-derived interference, an in vitro model was established to study the interaction of lpc virus (lpcv) and pcv2 in porcine alveolar macrophages (ams). the results showed that pcv2 reduced the lpcv infection ...201424370262
first detection of circovirus-like sequences in amphibians and novel putative circoviruses in fishes.the negative samples of a collection, established originally for seeking new adeno- and herpesviruses in lower vertebrates, were screened for the pres-ence of circoviruses by a consensus nested pcr targeting the gene coding for the replication-associated protein. six fish samples representing five species, namely asp (aspius aspius), roach (rutilus rutilus), common bream (abramis brama), round goby (neogobius melanostomus) and monkey goby (neogobius fluviatilis), as well as three frog samples we ...201424334078
influence of age on the effectiveness of pcv2 vaccination in piglets with high levels of maternally derived antibodies.two field studies were conducted to investigate the influence of age on the efficacy of vaccination against porcine circovirus diseases (pcvd) in animals with high levels of maternally derived antibodies (mda). a total of 416 piglets (study 1) and 600 piglets (study 2) were randomly allocated to one of three groups. two groups in each study received a single dose of a pcv2 subunit vaccine, one group at 1 week old and the other at 3 weeks of age. the third group was left untreated. animals vaccin ...201424315042
calculation of evolutionary correlation between individual genes and full-length genome: a method useful for choosing phylogenetic markers for molecular epidemiology.individual genes or regions are still commonly used to estimate the phylogenetic relationships among viral isolates. the genomic regions that can faithfully provide assessments consistent with those predicted with full-length genome sequences would be preferable to serve as good candidates of the phylogenetic markers for molecular epidemiological studies of many viruses. here we employed a statistical method to evaluate the evolutionary relationships between individual viral genes and full-lengt ...201324312527
multiple-class antimicrobial resistance surveillance in swine escherichia coli f4, pasteurella multocida and streptococcus suis isolates from ontario and the impact of the 2004-2006 porcine circovirus type-2 associated disease outbreak.the objective of this work was to describe trends in multiple-class antimicrobial resistance present in clinical isolates of escherichia coli f4, pasteurella multocida and streptococcus suis from ontario swine 1998-2010. temporal changes in multiple-class resistance varied by the pathogens examined; significant yearly changes were apparent for the e. coli and p. multocida data. although not present in the e. coli data, significant increases in multiple-class resistance within p. multocida isolat ...201424309129
optimization of virus detection in cells using massively parallel sequencing.massively parallel sequencing (mps)-based virus detection has potential regulatory applications. we studied the ability of one of these approaches, based on degenerate oligonucleotide primer (dop)-polymerase chain reaction (pcr), to detect viral sequences in cell lines known to express viral genes or particles. dop-pcr was highly sensitive for the detection of small quantities of isolated viral sequences. detected viral sequences included nodavirus, bracovirus, and endogenous retroviruses in hig ...201424309095
a commercial vaccine based on pcv2a and an experimental vaccine based on a variant mpcv2b are both effective in protecting pigs against challenge with a 2013 u.s. variant mpcv2b strain.during 2012 and 2013, an apparent increase in porcine circovirus associated disease occurred in the usa. a variant pcv2b strain designated mpcv2b was recovered from many of these cases. this raised concerns of a decrease in efficacy of commercially available pcv2 vaccines. the objective of this study was to compare the ability of a commercial pcv2a-based vaccine and an experimental mpcv2b-based vaccine to control mpcv2b-associated disease, lesions, and viremia in a challenge model. twenty-six ca ...201424269319
pcv2 on the spot-a new method for the detection of single porcine circovirus type 2 secreting cells.a porcine circovirus type 2 spot (pcv2-spot) assay was established to enumerate virus-secreting lymphocytes obtained from naturally infected pigs. the assay is based on the same principle as general elispot assays but instead of detecting cytokine or immunoglobulin secretion, pcv2 particles are immobilized and detected as filter spots. the method was used to evaluate the influence of various cell activators on the pcv2 secretion in vitro and was also applied to study the pcv2 secretion by lympho ...201424269204
regulatory role of ask1 in porcine circovirus type 2-induced apoptosis.porcine circovirus type 2 (pcv2), a major causative agent of postweaning multisystemic wasting syndrome which is an emerging and important swine disease, can induce apoptotic responses in vitro and in vivo. however, the molecular mechanism of pcv2-induced apoptosis is not well understood. apoptosis signal-regulating kinase 1 (ask1), serves as an upstream enzyme that activates the jnk and p38 mapk pathways, has been shown to play a target role in the regulation of apoptosis. here, we showed that ...201324210125
hsp70 positively regulates porcine circovirus type 2 replication in vitro.the hsp70 chaperone plays a central role in multiple processes within cells. porcine circovirus type 2 (pcv2) is the essential causal agent of post-weaning multisystemic wasting syndrome (pmws), which has spread worldwide. but the mechanism of pcv2 replication remains poorly understood. in this study, we firstly found the positive effect of heat stress on the replication of pcv2 in the continuous porcine monocytic cell line 3d4/31. downregulation of hsp70 by the specific chaperone inhibitor quer ...201324210099
development of a loop-mediated isothermal amplification method for rapid detection of pigeon circovirus.there are no effective antiviral treatments for pigeon circovirus (picv); thus, rapid diagnosis is critical for effective control of the disease caused by this virus. the recent development of a novel lamp technique that amplifies nucleic acids rapidly with high specificity and sensitivity under isothermal conditions has overcome some of the deficiencies of nucleic-acid-based diagnostic tests. we established a lamp method for rapid detection of picv using two pairs of primers that were designed ...201424193953
cultivation of pcv2 in swine testicle cells using the shell vial technique and monitoring of viral replication by qpcr and rt-qpcr.porcine circovirus type 2 (pcv2) is difficult to isolate. currently, no published articles have used the shell vial technique to isolate pcv2. in addition, the action of d-glucosamine on swine testicle cells (st) has not been evaluated properly. thus, the aim of this study was to determine an optimal concentration of d-glucosamine and to test the shell vial technique for pcv2 propagation in st cells. the optimal concentration of d-glucosamine was determined to be 100mm. because pcv2 is noncytopa ...201424183921
porcine circovirus type 2 stimulates plasmacytoid dendritic cells in the presence of ifn-gamma.porcine circovirus type 2 (pcv2) is recognized as the primary cause for the development of porcine circovirus-associated disease (pcvd). a number of reports demonstrated that pcv2 double-stranded (ds) dna inhibits interferon-α (ifn-α) production in cultures of porcine plasmacytoid dendritic cells (pdc). in addition, a short-lived peak of systemic ifn-α was detectable in the serum of pcv2-infected pigs, suggesting that the interaction of pcv2 with pdc may be more complex. culturing pdc supplement ...201324183591
suppression of the invasive potential of highly malignant tumor cells by kiom-c, a novel herbal medicine, via inhibition of nf-κb activation and mmp-9 expression.kiom-c, a novel herbal formula, was recently reported to be effective for treating pigs suffering from porcine circovirus-associated disease (pcvad). in addition, administration of kiom-c promoted clearance of influenza virus via production of antiviral cytokines, such as tnf-α and ifn-γ. since metastasis is the major cause of cancer-related death and the greatest challenge in cancer treatment, we investigated the effect of kiom-c on the metastatic potential of ht1080 and b16f10 cells. we observ ...201424174064
influence of porcine circovirus type 2 infections on bovine tuberculosis in wild boar populations.the wild boar is an important reservoir of bovine tuberculosis (btb) in south-western spain. some risk factors such as wild boar density or age have been associated with the presence of high prevalences of btb in wild boar. however, the influence of other risk factors such as co-infections with other pathogens has not yet been studied. this work aims to assess the influence of porcine circovirus type 2 (pcv-2) infection on btb prevalence and btb lesional patterns observed in wild boar. the prese ...201324171857
induction of robust immunity response in mice by dual-expression-system-based recombinant baculovirus expressing the capsid protein of porcine circovirus type 2.porcine circovirus type 2 (pcv2) is associated with post-weaning multisystemic wasting syndrome (pmws), an emerging swine disease that causes progressive weight loss, dyspnea, tachypnea, anemia, jaundice, and diarrhea in piglets. although baculovirus is an enveloped virus that infects insects in nature, it has emerged as a vaccine vector, and we used it to develop a novel candidate vaccine for a preventive or therapeutic strategy to control pcv2 infections.201324161107
[field trial on the simultaneous vaccination against porcine circovirus type 2 (pcv2) and mycoplasma hyopneumoniae].the objective of the present study was to investigate whether a combined or concurrent application of two vaccines against mycoplasma hyopneumoniae (m. hyo.) and porcine circovirus type 2 (pcv2) in suckling piglets can be as effective as the single use of both products.201324126996
the serological evidence in humans supports a negligible risk of zoonotic infection from porcine circovirus type 2.there are two porcine circovirus (pcv) genotypes, pcv-1 and pcv-2. in pigs, pcv-1 infection is asymptomatic but pcv-2 infection can cause severe respiratory disease and other pathology. although humans ingest pcv-contaminated foods and are exposed to pcv through other sources, the potential of pcv-2 as a zoonotic agent in humans and other species has not been fully explored. here, four recombinant proteins derived from the pcv-2 capsid gene were examined as antigens using the luciferase immunopr ...201324120888
a sensitive and specific nanoparticle-assisted pcr assay for rapid detection of porcine parvovirus.a novel nanoparticle-assisted polymerase chain reaction (nanopcr) assay to detect porcine parvovirus (ppv) is described here. primers for this assay were designed based on the conserved region of the nonstructural protein 1 (ns1) gene of ppv, which encodes one of the nonstructural proteins. the sensitivity of the ppv nanopcr assay was measured by using diluted recombinant plasmids in which the ppv ns1 gene had been inserted. the detection limit was 5.6 × 10(1) copies μl(-1) for the ppv nanopcr a ...201424117951
detection of pcv-2 dna in stool samples from infants vaccinated with rotateq®.rotarix® and rotateq® vaccines have led to a dramatic reduction in rotavirus disease worldwide. however, the detection of porcine circovirus type 1 (pcv-1) and 2 (pcv-2) dna in these vaccines raised some safety concerns. studies examining shedding of rotavirus in stool from rotavirus vaccine recipients have been performed but no published data exist regarding the shedding of pcv virus in stools of vaccinees. the goal of this study was to determine if pcv-1 and/or pcv-2 is shed in the feces of in ...201424104203
efficacy of a piglet-specific commercial inactivated vaccine against porcine circovirus type 2 in clinical field trials.the efficacy of a piglet-specific inactivated porcine circovirus type 2 (pcv2) vaccine was evaluated with clinical field trials, as recommended by the republic of korea's animal, plant & fisheries quarantine & inspection agency. three farms were selected on the basis of their history of postweaning multisystemic wasting syndrome. on each farm 60, 1-week-old pigs were randomly allocated to 1 of 2 treatment groups: vaccination at 1 and 3 wk of age or no vaccination. the 2-dose schedule of vaccinat ...201324101803
immune responses of mice immunized by dna plasmids encoding pcv2 orf 2 gene, porcine il-15 or the both.porcine circovirus type 2 (pcv2) is associated with many kinds of diseases including postweaning multisystemic wasting syndrome (pmws). it affects the immune system of swine and causes huge epidemic losses every year. in our previous study, we provided evidence that dna plasmid bearing porcine il-15 (pvax-pil-15) might serve as an immune enhancer for dna plasmid encoding porcine reproductive and respiratory syndrome virus gp5 gene. in this study, pcv2 open reading frame (orf)2 gene was cloned in ...201324091312
snatch-farrowed, porcine-colostrum-deprived (sf-pcd) pigs as a model for swine infectious disease research.the current study tested the benefit of commercially available spray-dried bovine colostrum (the saskatoon colostrum company, saskatoon, saskatchewan) in raising snatch-farrowed, porcine-colostrum-deprived (sf-pcd) pigs. in experiment 1, 12 sf-pcd pigs received a liquid diet composed mainly of bovine colostrum from birth to day 10; 6 remained on the same liquid diet (col), and the other 6 were fed a diet composed mainly of milk replacer (rpl) until weaning. in experiment 2, 12 sf-pcd pigs were f ...201324082397
effect of sophora subprosrate polysaccharide on oxidative stress induced by pcv2 infection in raw264.7 cells.in this study, an oxidative stress model was first developed in a mouse macrophage cell line (raw264.7 cells) by infecting the cells with porcine circovirus type 2 (pcv2). the regulatory effect of sophora subprosrate polysaccharide (ssp) on pcv2-induced oxidative stress was investigated. the results showed that after infection with pcv2, reactive oxygen species (ros) and nitric oxide (no) production, myeloperoxidase (mpo) activity, and inducible nitric oxide synthase (inos) expression were signi ...201324080450
detection of contaminants in cell cultures, sera and trypsin.the aim of this study was standardization and application of polymerase chain reaction (pcr) for the detection of contaminants in cell cultures, sera and trypsin. five pcr protocols were standardized to assess the presence of genetic material from mycoplasma, porcine circovirus 1 (pcv1), bovine leukemia virus (blv) or bovine viral diarrhea virus (bvdv) in cell culture samples. pcr reactions for the genes gapdh and beta-actin were used to evaluate the efficiency of nucleic acid extraction. the pc ...201324071554
investigation of a regulatory agency enquiry into potential porcine circovirus type 1 contamination of the human rotavirus vaccine, rotarix: approach and outcome.in january 2010, porcine circovirus type 1 (pcv1) dna was unexpectedly detected in the oral live-attenuated human rotavirus vaccine, rotarix (glaxosmithkline [gsk] vaccines) by an academic research team investigating a novel, highly sensitive analysis not routinely used for adventitious agent screening. gsk rapidly initiated an investigation to confirm the source, nature and amount of pcv1 in the vaccine manufacturing process and to assess potential clinical implications of this finding. the inv ...201324056737
porcine circovirus (pcv) removal by q sepharose fast flow chromatography.the recently discovered contamination of oral rotavirus vaccines led to exposure of millions of infants to porcine circovirus (pcv). pcv was not detected by conventional virus screening tests. regulatory agencies expect exclusion of adventitious viruses from biological products. therefore, methods for inactivation/removal of viruses have to be implemented as an additional safety barrier whenever feasible. however, inactivation or removal of pcv is difficult. pcv is highly resistant to widely use ...201524039195
concurrent porcine circovirus type 2a (pcv2a) or pcv2b infection increases the rate of amino acid mutations of porcine reproductive and respiratory syndrome virus (prrsv) during serial passages in pigs.porcine reproductive and respiratory syndrome virus (prrsv) has a high degree of genetic and antigenic variability. the purpose of this study was to determine if porcine circovirus type 2 (pcv2) infection increases genetic variability of prrsv during serial passages in pigs and to determine if there is a difference in the prrsv mutation rate between pigs concurrently infected with pcv2a or pcv2b. after 8 consecutive passages of prrsv alone (group 1), prrsv with pcv2a (group 2), or pcv2b (group 3 ...201324036229
a one-step rt-pcr assay to detect and discriminate porcine reproductive and respiratory syndrome viruses in clinical specimens.outbreaks of highly pathogenic porcine reproductive and respiratory syndrome virus (hp-prrsv) have led to large economic losses and, subsequently, have drawn great attention to its diagnosis and prevention. to facilitate rapid discrimination of hp-prrsv from classical prrsv (c-prrsv), we developed a one-step rt-pcr assay. primer specificities were evaluated with rna extracted from 8 viral strains and our results revealed that the primers had a high specificity for prrsv. the assay sensitivity wa ...201324035936
detection of genetic characterization of porcine circovirus 2 (pcv2) in brazilian wildlife boars.a semi-intensive wildlife boars farm presented a clinical history of high mortality in 70 - 90 days-old pigs (> 50 %). two 90 days-old animals with weight loss and wasting were necropsied and the samples tested for pcv2 by polymerase chain reaction (pcr). the genetic material of pcv2 was sequenced and classified into the pcv2a genotype together with pcv2 sequences obtained from samples of poland, brazil, slovenia and greece wild boars.201224031922
retrospective study on porcine circovirus-2 by nested pcr and real time pcr in archived tissues from 1978 in brazil.porcine circovirus-2 (pcv-2) infection is currently considered an important disease of swine. the pathogenic agent was first described in brazil in 2000. this study detected the pcv-2 dna in four brazilian pig tissues collected between 1978 and 1979. this observation is the oldest description of this virus in brazil.201124031736
malakoplakia with digestive tract involvement in a pig.malakoplakia is a rare, granulomatous, inflammatory disease that mimics malignant tumors and can affect any organ. herein is described a case of malakoplakia in a 10-month-old slaughter pig. diffuse, pleomorphic, round cell infiltrates, mainly histiocytes, with a tumor-like growth pattern at gross examination, infiltrated the stomach, pancreas, omentum, and mesenteric lymph nodes. the histiocytes and multinucleated giant cells had concentric, target-like inclusions known as michaelis-gutmann bod ...201424021559
activation of nf-κb contributes to production of pig-major acute protein and serum amyloid a in pigs experimentally infected with porcine circovirus type 2.acute phase proteins (apps) have protective and regulatory roles in the inflammatory response. previous studies indicate that apps in serum change after pigs are infected with porcine circovirus type 2 (pcv2), but the mechanisms underlying app production have remained unclear. in this present study, 35-day-old pigs were challenged with pcv2 and responses compared to an uninfected control group. to investigate the concentrations of apps in serum and the activity of nf-κb in the liver, five pigs i ...201324011594
a multiplex rt-pcr assay for rapid and differential diagnosis of four porcine diarrhea associated viruses in field samples from pig farms in east china from 2010 to 2012.since october 2010, clinical outbreaks of diarrhea in suckling piglets have reemerged in pig-producing areas of china, causing an acute increase in the morbidity and mortality in young piglets. four viruses, porcine epidemic diarrhea virus (pedv), transmissible gastroenteritis virus (tgev), porcine group a rotaviruses (gar), and porcine circovirus 2 (pcv2), are the major causative agents of enteric disease in piglets. a novel multiplex reverse transcription-polymerase chain reaction (mrt-pcr) wa ...201323988656
oral immunogenicity of a plant virus vector based porcine circovirus antigen - short communication.a recombinant cucumber mosaic virus based expression system has been developed for the production of an immunogenic porcine circovirus epitope. the resulting nanoparticle was shown to elicit specific immune response in mice and pigs, when administered parenterally. to evaluate the oral applicability of this vaccine candidate, two experiments were performed. in the first one, the resistance of the vector itself to mucosal environment was tested in mice. cucumber mosaic virus particles fed to mice ...201323974938
detection of porcine circovirus type 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv) antibodies in meat juice samples from polish wild boar (sus scrofa l.).pcv2 and prrsv are two important pathogens of domestic swine. there is considerable evidence that the infection is also present in wild boars. meat juice provides an alternative to serum for antibody testing, and it has been used in testing for many important porcine infectious diseases. samples of brachial muscle were collected from 142 wild boars shot in different regions of poland during the 2006/2007 and 2007/2008 hunting seasons. meat juice harvested from muscle samples was tested using an ...201323974935
synergistic effects of sequential infection with highly pathogenic porcine reproductive and respiratory syndrome virus and porcine circovirus type 2.porcine reproductive and respiratory syndrome virus (prrsv) is the causative agent of porcine reproductive and respiratory syndrome (prrs) and porcine circovirus type 2 (pcv2) is associated with postweaning multisystemic wasting syndrome (pmws) in pigs. coinfection with highly pathogenic prrsv (hp-prrsv) and pcv2 in the field has recently become extensive in some asian countries. a synergistic pathogenicity between prrsv and pcv2 infections has previously been reported. however, the consequences ...201323971711
vero cells expressing porcine circovirus type 2-capsid protein and their diagnostic application.porcine circovirus type 2 (pcv2) is the causative agent of postweaning multisystemic wasting syndrome (pmws) in swine. although the incidences of pcv2-related diseases are ubiquitous throughout the world, the serological tools are rather limited, mainly because the virus does not induce any cytopathic effects in cells. the purpose of this study was to develop a rapid, sensitive and easy quantitative immunofluorescence assay (qifa) using the recombinant pcv2 nucleocapsid protein (ncp) for the det ...201323954842
improvement of technical results following use of ingelvac circoflex in a dutch organic breeding and fattening farm: a case report.porcine circovirus type 2 (pcv2) is a ubiquitous infection and major cause of production loss for the pig industry. the aim of this study was to evaluate the effect of vaccination against pcv2 on technical results of pigs on an organic breeding and fattening farm, focussing on growth and mortality of weaned piglets and fattening pigs. the study was based on retrospective data between january 2009 and may 2011. during the study period, three subsequent vaccination strategies were used: 1. stellam ...201323923656
interaction of porcine circovirus type 2 replication with intracellular redox status in vitro.redox status influences replication of some viruses but its effect on porcine circovirus type 2 (pcv2), the primary causative agent of the emerging swine disease post-weaning multisystemic wasting syndrome is not known. the interaction of pcv2 replication with intracellular redox status in pk15 cells was examined in this study.201323902724
prevalence of swine viral and bacterial pathogens in rodents and stray cats captured around pig farms in korea.in 2008, 102 rodents and 24 stray cats from the areas around 9 pig farms in northeast south korea were used to determine the prevalence of the following selected swine pathogens: ten viral pathogens [porcine epidemic diarrhea virus (pedv), transmissible gastroenteritis virus (tgev), rotavirus, classical swine fever virus (csfv), porcine circovirus type 2 (pcv2), encephalomyocarditis virus (emcv), porcine reproductive and respiratory syndrome virus (prrsv), porcine parvovirus (ppv), pseudorabies ...201323892461
a nanoparticle-assisted pcr assay to improve the sensitivity for rapid detection and differentiation of wild-type pseudorabies virus and gene-deleted vaccine strains.nanoparticle-assisted polymerase chain reaction (nanopcr) is a novel method for the rapid amplification of dna and has been adopted for the detection of virus because of its simplicity, rapidity, and specificity. a nanopcr assay was developed to detect and differentiate wild-type and gene-deleted pseudorabies virus (prv). three pairs of primers for nanopcr developed in this study were selected from conserved regions of prv, producing specific amplicons of 431 bp (gb), 316 bp (ge), and 202 bp (gg ...201323872268
complete nucleotide sequence of porcine circovirus 2 isolated from piglets in china.a new strain of canine distemper virus, strain hx, has been isolated from piglets in china, and its complete genome has been sequenced and analyzed. phylogenetic analysis suggests that hx belongs to the 2d genotype cluster and it is highly prevalent in china.201323868119
multiple routes of porcine circovirus type 2 transmission to piglets in the presence of maternal immunity.porcine circovirus 2 (pcv2), the cause of porcine circovirus-associated disease (pcvad), is widespread in swine farms throughout the united states with vaccine controlling disease, but not eliminating infection. we examined the pcv2 virological and immunological status of sows, pre-suckling piglets, and the farrowing environment of sow farms to determine pcv2 exposure risks, transmission dynamics, and immunological impacts at the time of farrowing. pcv2 was widely distributed in animals and the ...201323867083
development of a loop-mediated isothermal amplification assay for the detection of porcine hokovirus.hokoviruses have recently been detected as pathogens belonging to the family parvoviridae, which comprises porcine hokovirus (phov) and bovine hokovirus (bhov). in this study, we developed a loop-mediated isothermal amplification (lamp) assay for the rapid, specific and sensitive detection of phov. a set of four primers specific for six regions within the phov vp1/2 genes was designed using online software. the reaction temperature and time were optimized at 65°c and 60 min, respectively. lamp p ...201323850717
development and evaluation of a loop-mediated isothermal amplification method for rapid detection and differentiation of two genotypes of porcine circovirus type 2.porcine circovirus type 2 (pcv2) is one of the major swine viral diseases and has caused significant economic loss to pig producers. pcv2 has been divided into two major genotypes: pcv2a, pcv2b. a loop-mediated isothermal amplification (lamp) method was developed for the detection and differentiation of pcv2a and pcv2b in clinical samples.201423845855
epitope screening of the pcv2 cap protein by use of a random peptide-displayed library and polyclonal antibody.capsid protein (cap), the only structural protein of porcine circovirus 2 (pcv2), is involved in the host protective response and is a target for vaccine development. to find a rapid and easy way to fully map the antigenic epitopes of cap, purified cap-specific polyclonal antibodies were used to screen a random heptapeptide phage display library. after three rounds of screening, twenty phage clones that had binding activity to cap-specific antibodies (tested by phage elisa) were sequenced. when ...201323845304
correlation of the cyclin a expression level with porcine circovirus type 2 propagation efficiency.porcine circovirus type 2 (pcv2) is an important pathogen in swine, and it is assumed that pcv2 replication is cell cycle dependent (especially during s phase). however, the cellular molecules that regulate pcv2 replication have not been fully identified. here, we cloned the porcine cyclin a (cyca) and cdk2 genes, the major regulators of the s phase, and established cyca or cdk2 overexpression and lower-expression cell lines. the propagation efficiency of strains pcv2a/cl or pcv2b/yj in these ce ...201323836398
effectiveness of porcine circovirus type 2 vaccination in reducing the severity of post-weaning multisystemic wasting syndrome in pigs.changes in the severity of post-weaning multisystemic wasting syndrome (pmws) and the effect of vaccination against porcine circovirus type 2 (pcv2) on the severity of pmws and the prevalence of pcv2 were assessed on 50 english pig farms from 2008 to 2010. pmws severity on farms before and after pcv2 vaccination was estimated by combining data on post-weaning mortality, morbidity and proportion of pigs positive for pcv2 by pcr. at the first visit (before vaccination), all 50 farms were seroposit ...201323830301
association of concurrent porcine circovirus (pcv) 2a and 2b infection with pcv associated disease in vaccinated pigs.investigations were performed to characterize porcine circovirus (pcv) 2 infection in 10 week old pigs from a case of apparent vaccine failure. thirty serum samples were collected from affected or non-affected pigs and tested for anti-pcv2 antibodies and pcv2 dna. to address potential pcv2 vaccine compliance issues, samples were tested for antibodies against baculovirus and mycoplasma hyopneumoniae antigens present in the pcv2 vaccine utilized in this herd. both pcv2a and pcv2b dna were detected ...201323829995
molecular analysis of porcine circovirus type 2 strains from uruguay: evidence for natural occurring recombination.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. genomic structure consists of three major open reading frames (orfs). orf1 (rep gene) encodes replication-related proteins, orf2 (cap gene) encodes the capsid protein and orf3 encodes a protein putatively involved in virus-induced apoptosis. based on cap gene sequences, pcv2 strains are classified into two main genotypes, pcv2a ...201323806516
torque teno sus virus (ttsuv) in tissues of pigs and its relation with the occurrence of postweaning multisystemic wasting syndrome.torque teno sus virus (ttsuv) is a member of the recently created family anelloviridae. two distinct species of ttsuvs, 1 (ttsuv1) and 2 (ttsuv2) have been reported so far in domestic pigs and wild boars. although ttsuvs have not been clearly linked to any specific disease of pigs, a relation between ttsuv infections and postweaning multisystemic wasting syndrome (pmws) has been suggested. to examine further this possibility, the present study was conducted in search for ttsuv1 and ttsuv2 genome ...201323783757
identification and characterization of two novel transcription units of porcine circovirus 2.porcine circovirus type 2 (pcv2) infection is associated with porcine circovirus-associated diseases in pigs, which is a serious threat to the swine industry worldwide. to date, only three open reading frames (orfs) within the pcv2 genome have been reported: orf1 codes for two replicase proteins (rep and rep'), orf2 for the structural protein (cap), and orf3 for a protein implicated in cellular apoptosis. in this study, based on transcription analysis of orf3 mrna, a potential orf4 mrna was dete ...201323775757
three new emerging subgroups of torque teno sus viruses (ttsuvs) and co-infection of ttsuvs with porcine circovirus type 2 in china.torque teno sus viruses (ttsuvs) are non-enveloped viruses and have single-stranded, negative sense circular dna genomes and are widely distributed in pigs. but till now, the prevalence of ttsuvs with porcine circovirus type 2 (pcv2) in pig herds of china is not very clear; and the genetic variation among different ttsuvs isolate is very large and need to divide the subgroups. in this study, the co-infection with ttsuvs and porcine circovrius (pcv) in the pig population of china was investigated ...201323758726
hepatitis e virus and porcine-derived heparin. 201323751114
genetic characterization of porcine circovirus type 2 from pigs with porcine circovirus associated diseases in argentina.porcine circovirus type 2 (pcv-2) has been associated with syndromes grouped by the term porcine circovirus associated diseases (pcvad). the pcv-2 isolates have been grouped into two major groups or genotypes according to their nucleotide sequence of whole genomes and/or orf-2: pcv-2b, which have, in turn, been subdivided into three clusters (1a-1c), and pcv-2a, which has been subdivided into five clusters (2a-2e). in the present study, we obtained 16 sequences of pcv-2 from different farms from ...201123738099
porcine cd74 is involved in the inflammatory response activated by nuclear factor kappa b during porcine circovirus type 2 (pcv-2) infection.human cd74 induces a signalling cascade that results in the activation of nuclear factor kappa b (nf-κb); however, porcine cd74 has not been widely studied. in this study, we show that porcine cd74 is mainly expressed in cells of the macrophage lineage and can be induced by lipopolysaccharide (lps), polyinosinic acid-polycytidylic acid [poly(i:c)], and infection with porcine circovirus type 2 (pcv2) in vitro. in addition, we confirmed that porcine cd74 can activate nf-κb by promoting iκbα degrad ...201323736979
the use of null models and partial least squares approach path modelling (pls-pm) for investigating risk factors influencing post-weaning mortality in indoor pig farms.although post-weaning mortality (pwm) in pig farming is mainly due to the effect of pathogens, farm type or swine management are also directly or indirectly involved. in this work, we used null models and the partial least squares approach (pls) to structural equation modelling, also known as pls path modelling (pls-pm), to explore whether farm type, swine management and pathogens, including porcine circovirus type 2, swine influenza virus, porcine reproductive and respiratory syndrome virus and ...201423725592
transcription analysis of the porcine alveolar macrophage response to porcine circovirus type 2.porcine circovirus type 2 (pcv2) is the causal agent of postweaning multisystemic wasting syndrome (pmws), which has severely impacted the swine industry worldwide. pcv2 triggers a weak and atypical innate immune response, but the key genes and mechanisms by which the virus interferes with host innate immunity have not yet been elucidated. in this study, genes that control the response of primary porcine alveolar macrophages (pams), the main target of pcv2, were profiled in vitro.201323711280
humoral response and colostral antibody transfer following 'one-dose' pre-mating vaccination of sows against porcine circovirus type-2.the objective of this study was to investigate the presence of porcine circovirus type 2 (pcv2) dna and antibody to the virus in the serum and colostrum of sows vaccinated prior to mating and in their offspring. seventy-seven sows were randomly distributed into vaccinated (v, n=36) and non-vaccinated (nv, n=41) groups. one week before mating, sows were given a pcv2 vaccine (v group) or pbs (nv group) im. blood samples were taken from the sows at fixed time-points and colostrum samples were taken ...201323707054
paralysis in pigs with spinal cord injury due to porcine circovirus type 2 (pcv-2) infection. 201323694922
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 ...201323683855
variable performance of a human derived sarcoptes scabiei recombinant antigen elisa in swine mange diagnosis.the performance of an indirect elisa test based on sarcoptes scabiei var hominis recombinant antigen ssλ20δb3 (rec-elisa), to diagnose pig mange was investigated in 15 experimentally infected and non-infected pigs and 692 commercial pigs from 16 herds in southeast spain. these latter animals included 6-7 month old fatteners (13 herds), 11-12 month old replacement sows (1 herd) and ≥24 month old breeding sows (7 herds). all pigs were examined for mites in ear skin scrapings and the presence of s. ...201323683576
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 ...201323661391
[metagenomics-based detection of swine viruses].extreme varieties of viruses exist in the environment and animals, some of which are unknown. however, many unknown viruses are barely detected by means of conventional virus isolation and pcr assay.201323627112
nontransmission of porcine circovirus 2 (pcv2) by embryo transfer.two experiments were conducted to determine the association of porcine circovirus type 2 (pcv2) with embryos and the risk of viral transmission by embryo transfer. in the first experiment, 240 embryos from uninfected donors were exposed to pcv2a 10(4)tcid50/ml in vitro before transfer to seronegative recipients; in the second experiment, 384 embryos recovered from infected donors, 10 days after donor inoculation with pcv2, were transferred to seronegative recipients. in total, 1120 embryos and/o ...201323622941
induction of mucosal immunity by intranasal immunization with recombinant adenovirus expressing major epitopes of porcine circovirus-2 capsid protein.porcine circovirus-2 (pcv-2) is primarily transmitted through mucosa, thus the mucosal immunity may constitute an essential feature of vaccination strategies against pcv-2 infection. mucosal immunity elicited by recombinant replication-deficient adenovirus expressing the major epitopes of pcv-2 capsid protein (rad/cap/518) via intranasal (i.n.), intramuscular (i.m.) or oral routes in mice were evaluated. immunization with rad/cap/518 via i.n. route induced higher titers of iga in saliva, broncho ...201323618367
development and characterization of two porcine monocyte-derived macrophage cell lines.cell lines cδ2+ and cδ2- were developed from monocytes obtained from a 10-month-old, crossbred, female pig. these cells morphologically resembled macrophages, stained positively for α-naphthyl esterase and negatively for peroxidase. the cell lines were bactericidal and highly phagocytic. both cell lines expressed the porcine cell-surface molecules mhci, cd11b, cd14, cd16, cd172, and small amounts of cd2; however, only minimal amounts of cd163 were measured. the lines were negative for the mouse ...201323610747
antibody responses induced in mice immunized with recombinant adenovectors expressing chimeric proteins of various porcine pathogens.porcine reproductive and respiratory syndrome virus (prrsv), porcine circovirus type 2 (pcv2) and mycoplasma (m.) hyopneumoniae are swine pathogens of economic importance. although vaccines are available for each pathogen, no commercial bivalent vaccines have been developed so far. in this study, recombinant adenovectors (advs) expressing proteins of each pathogen were developed and their immunogenicity tested in mice. the proteins of interest were the glycoprotein gp5 of prrsv, the capsid (cap) ...201323583895
amino acid mutations in the capsid protein produce novel porcine circovirus type 2 neutralizing epitopes.porcine circovirus type 2 (pcv2) is associated with postweaning multisystemic wasting syndrome in pigs. a monoclonal antibody (mab) 8e4 against the pcv2 capsid protein has the capacity to neutralize the virus. however, this mab can only react with some pcv2a strains (lg, cl, and jf2; mab 8e4-positive strains), but does not cross-react with some pcv2b strains (yj and jf; mab 8e4-negative strains). in the present study, site-directed mutagenesis was performed targeting the external amino acids of ...201323582511
detection of a porcine boca-like virus in combination with porcine circovirus type 2 genotypes and torque teno sus virus in pigs from postweaning multisystemic wasting syndrome (pmws)-affected and non-pmws-affected farms in archival samples from great britain.in this study we detail the detection and genetic analysis of a novel porcine boca-like virus (pbo-likev) in archival sera and tissue samples from pigs from farms in great britain. we also investigate the distribution of porcine circovirus type 2 (pcv2) genotypes and torque teno sus virus (ttsuv) genogroups 1 and 2 in combination with this novel pbo-likev. pbo-likev was detected in over 70% of all tissues investigated. over 24% of all tissues recovered from pmws-affected animals had all viruses ...201323578709
genetic evolution and phylogenetic analysis of porcine circovirus type 2 infections in southern china from 2011 to 2012.porcine circovirus type 2 (pcv2), the primary causative agent of porcine circovirus-associated diseases (pcvads), is a serious economic problem for the swine industry worldwide. three major pcv2 genotypes (pcv2a, pcv2b, and pcv2c), have been identified. to explore the prevalence of different subgroups of pcv2 in southern china, 66 pcv2 isolates collected during 2011-2012 were analyzed. pcv2b was the predominant genotype circulating in southern china from 2011 to 2012. moreover, subtype 1c was th ...201323562733
prevalence of porcine hokovirus and its co-infection with porcine circovirus 2 in china.here, we report the frequency of porcine hokovirus (phov) infection and its co-infection with porcine circovirus 2 (pcv2) in china. a total of 485 domestic pig samples were tested for both phov and pcv2, and ns1 gene sequences from 11 phov strains were used for phylogenetic analysis. the prevalence of phov and pcv2 was 51.3 % and 36.3 %, respectively, and co-infection occurred in 20.2 %. phovs from the chinese mainland showed a close relationship to those isolated in hong kong. co-infection with ...201323558802
[construction and immunogenicity analysis of recombinant replication-defective human adenovirus type 5 bearing the porcine circovirus type 2 cap protein gene].to construct a recombinant replication-defective human adenovirus type 5 expressing cap protein of pcv2 and test the immunological efficacy in mice. in this study, the recombinant replication-defective human adenovirus type 5, named as rad5-cap (wt-rad5), was constructed through homologous recombination internally in the hek293ad cells after co-transfection of the pac i-linearized backbone plasmid and the shuttle plasmid pacad5cmv-cap containing the open reading frame (orf2) of the porcine circo ...201323547376
evidence for different patterns of natural inter-genotype recombination between two pcv2 parental strains in the field.co-infection with different virus strains is a precondition for genome recombination, which give rise to continuous evolution of porcine circovirus type 2 (pcv2). in the present study, 32 pcv2 positive clinical samples from the diseased and dead pigs were identified by classic pcr. 15 of 32 (46.8%) clinical samples were identified as infection with both pcv2a and pcv2b using genotype-specific pcr. 13/15 of pcv2 strains were identified as recombinants using sequencing analysis, phylogenetic analy ...201323545543
efficacy of parenteral vaccination against porcine circovirus type 2 (pcv2) in seropositive piglets.this study investigated if parenteral administration of a prototype adjuvanted vaccine against porcine circovirus type 2 (pcv2) could override maternally derived antibodies and induce acquired immunity in young piglets. piglets with high levels of maternal pcv2 antibodies at 1 wk of age were randomly grouped into vaccinates and controls on the basis of body weight and inoculated with the vaccine or a control preparation twice, with an interval of 3 wk. both groups were challenged 3 wk after the ...201223543956
small-sized circular genomes similar to genome of porcine circovirus 2.circular genomes smaller than and similar to the genome of porcine circovirus 2 were obtained from pig tissues along with the full-length genome of porcine circovirus 2. the 922-, 839-, and 617-nucleotide-long genomes exhibit high homology to the rep gene plus the origin of replication sequence of porcine circovirus 2.201323538903
comparative evaluation of conventional polymerase chain reaction (pcr), with loop-mediated isothermal amplification and sybr green i-based real-time pcr for the quantitation of porcine circovirus-1 dna in contaminated samples destined for vaccine production.porcine circovirus type1 (pcv1), described initially as a contaminant of a porcine kidney cell line, is ubiquitous within the swine population the presence of pcv1 in porcine cell lines can lead to contamination during both human and porcine vaccine production. therefore, a rapid, specific, sensitive and practical method is needed for the detection of pcv1 in bio-products. the aim of this study was to compare three assays in their ability to accurately quantify pcv1 virus in biological samples, ...201323538038
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