scholarly journals Identification of porcine circovirus type 2 (PCV2), type 3 (PCV3) and porcine parvovirus (PPV) in swine by multiplex PCR test

2021 ◽  
Vol 20 (03) ◽  
pp. 11-17
Author(s):  
Phat X. Dinh

This study aimed to simultaneously detect three important viruses reported to be involved in the reproductive problems of sows. A multiplex PCR (mPCR) test was developed to provide rapid diagnosis of porcine circovirus type 2 and 3 (PCV2, PCV3) and to illustrate parvovirus (PPV) prevalence in sow herds. Three pairs of specific primers were designed to target PCV2 Cap gene, PCV3 Cap gene and PPV NS1 gene, with predicted mPCR products of 702 bp, 267 bp and 380 bp, respectively. The detection limit of mPCR was 100 copies/reaction per target gene. The mPCR was run against a panel of 94 swine serum samples whose infection status had been pre-determined by commercial real-time PCR kits. Sequencing of mPCR products performed with clinical serum samples accurately confirmed the results. Overall, the results indicated that the mPCR functioned accurately and specifically and matched 100% with the single-target real-time PCRs. The mPCR was developed successfully and can be used in routine diagnosis of PCV2, PCV3 and PPV.

2020 ◽  
Author(s):  
Thoai Kim Tran ◽  
Trang Thi Thanh Nguyen ◽  
Hiep Lai Xuan Vu ◽  
Phat Xuan Dinh

Abstract Background : Aiming to simultaneously detect three important viruses known to be involved in reproductive problems of sows, a multiplex PCR (mPCR) test was developed to provide rapid diagnosis of porcine circovirus type 2 and 3 (PCV2, PCV3) and to illustrate parvovirus (PPV) prevalence in sow herds. Methods : Three pairs of specific primers were designed to target PCV2 Cap gene, PCV3 Cap gene and PPV NS1 gene, with predicted mPCR products of 702 bp, 267 bp and 380 bp, respectively. Results : The detection limit of mPCR was 100 copies/ reaction per target gene. Sequencing of mPCR products performed with clinical serum samples accurately confirmed results. The mPCR was run against a panel of 94 swine serum samples whose infection status had been pre-determined by commercial real-time PCR kits. Overall, the mPCR results matched 100% with the real-time PCRs. Conclusions : The developed mPCR test functions successfully and can be used in routine rapid diagnosis of PCV2, PCV3 and PPV.


2020 ◽  
Author(s):  
Jan Plut ◽  
Urska Jamnikar-Ciglenecki ◽  
Irena Golinar-Oven ◽  
Tanja Knific ◽  
Marina Stukelj

Abstract Background: Porcine circovirus type 3 is the most recently discovered porcine circovirus, and an emerging pathogen. In this study the status of its presence on some Slovenian farms is reported. The effectiveness of the vaccine against porcine circovirus type 2 was assessed against porcine circovirus type 3.Group samples of oral fluid, faeces and individual serum samples were taken from six different pig categories and tested for presence of viral DNA, using both real time and conventional PCR. Positive samples were subjected to direct Sanger sequencing. Nucleotide sequences were analyzed and compared to GenBank PCV3 sequences.Results: Positive samples were sent for genome sequencing, which confirmed the presence of virus in all different pig categories on five farms. A high to moderate correlation of strong statistical significance was found between individual serum samples, oral fluid and faeces. Slovenian PCV3 was found to be distributed in a way similar to that of other countries. Slovenian PCV3 nt sequences are highly related, sharing more than 99.5 % nt identity. On one farm a commercially available vaccine against porcine circovirus type 2 was used on 3-week-old pigs. It did not affect the presence of porcine circovirus type 3 in oral fluid or sera of any of the seven age groups of pigs, each with two control groups.Conclusions: The results constitute the first discovery of the virus in Slovenia. Genome sequencing has revealed a high degree of similarity between Slovenian and GenBank isolates.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Ellen Kathrin Link ◽  
Matthias Eddicks ◽  
Liangliang Nan ◽  
Mathias Ritzmann ◽  
Gerd Sutter ◽  
...  

Abstract Background The porcine circovirus type 2 (PCV2) is divided into eight genotypes including the previously described genotypes PCV2a to PCV2f and the two new genotypes PCV2g and PCV2h. PCV2 genotyping has become an important task in molecular epidemiology and to advance research on the prophylaxis and pathogenesis of PCV2 associated diseases. Standard genotyping of PCV2 is based on the sequencing of the viral genome or at least of the open reading frame 2. Although, the circovirus genome is small, classical sequencing is time consuming, expensive, less sensitive and less compatible with mass testing compared with modern real-time PCR assays. Here we report about a new PCV2 genotyping method using qPCR. Methods Based on the analysis of several hundred PCV2 full genome sequences, we identified PCV2 genotype specific sequences or single-nucleotide polymorphisms. We designed six TaqMan PCR assays that are specific for single genotypes PCV2a to PCV2f and two qPCRs targeting two genotypes simultaneously (PCV2g/PCV2d and PCV2h/PCV2c). To improve specific binding of oligonucleotide primers and TaqMan probes, we used locked nucleic acid technology. We evaluated amplification efficiency, diagnostic sensitivity and tested assay specificity for the respective genotypes. Results All eight PCV2 genotype specific qPCRs demonstrated appropriate amplification efficiencies between 91 and 97%. Testing samples from an epidemiological field study demonstrated a diagnostic sensitivity of the respective genotype specific qPCR that was comparable to a highly sensitive pan-PCV2 qPCR system. Genotype specificity of most qPCRs was excellent. Limited unspecific signals were obtained when a high viral load of PCV2b was tested with qPCRs targeting PCV2d or PCV2g. The same was true for the PCV2a specific qPCR when high copy numbers of PCV2d were tested. The qPCR targeting PCV2h/PCV2c showed some minor cross-reaction with PCV2d, PCV2f and PCV2g. Conclusion Genotyping of PCV2 is important for routine diagnosis as well as for epidemiological studies. The introduced genotyping qPCR system is ideal for mass testing and should be a valuable complement to PCV2 sequencing, especially in the case of simultaneous infections with multiple PCV2 genotypes, subclinically infected animals or research studies that require large sample numbers.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Zicheng Ma ◽  
Mengda Liu ◽  
Zhaohu Liu ◽  
Fanliang Meng ◽  
Hongyu Wang ◽  
...  

Abstract Background Porcine circovirus type 2 (PCV2) is one of the crucial swine viral pathogens, caused porcine circovirus associated diseases (PCVAD). Shandong province is one of the most important pork producing areas and bears a considerable economic loss due to PCVAD. However, there is limited information on epidemiology and coinfection rate of PCV2 with other critical swine diseases in this area, such as porcine reproductive and respiratory syndrome virus (PRRSV), classical swine fever virus (CSFV), Pseudorabies virus (PRV), and porcine epidemic diarrhea virus (PEDV). Results Overall, 89.59% serum samples and 36.98% tissue samples were positive for PCV2 specified ELISA and PCR positive for PCV2, respectively. The coinfection rates of PCV2 with PRRSV, PRV, CSFV, and PEDV were 26.73%, 18.37%, 13.06%, and 3.47%, respectively. Moreover, genetic characteristic of PCV2 were analyzed based on the cap genes showing that PCV2d is the dominant sub-genotype circulating in the province. Conclusions Our findings reveal that PCV2d, as the dominant strain, is prevailing in pig farms in Shandong province at high levels. There was a high frequency of coinfection of PCV2 and PRRSV.


2009 ◽  
Vol 16 (6) ◽  
pp. 830-834 ◽  
Author(s):  
D. M. Madson ◽  
A. R. Patterson ◽  
S. Ramamoorthy ◽  
N. Pal ◽  
X. J. Meng ◽  
...  

ABSTRACT The aims of this study were to determine if porcine circovirus type 2 (PCV2) vaccination of the dam is effective in preventing fetal PCV2 infection and reproductive failure. Twelve pregnant, PCV2-naïve sows were randomly divided into four groups, with three sows in each group. Group 1 sows served as noninoculated, nonvaccinated negative controls, group 2 sows were vaccinated with a commercially available PCV2 vaccine at 28 days of gestation and were not inoculated, group 3 sows were vaccinated at 28 days of gestation and inoculated with PCV2b at 56 days of gestation, and group 4 sows were inoculated with PCV2b but were not vaccinated. Serum samples from all sows were collected weekly throughout the gestation period, and sows were allowed to farrow naturally. At parturition, sow colostrum samples, presuckle serum samples, and tissues from the piglets were collected. Reproductive failure was not observed under the study conditions. PCV2 vaccination induced PCV2-specific immunoglobulin G and serum neutralizing antibodies in sows from groups 2 and 3 and prevented detectable PCV2 viremia in the dams after challenge. In group 3, PCV2 DNA was detected in colostrum samples, fetuses, and live-born pigs; however, microscopic lesions and PCV2-specific antigen were not present in any of the fetuses in this group. The results from this study indicate that vertical transmission of PCV2 can occur in PCV2-vaccinated dams.


2020 ◽  
Vol 161 ◽  
pp. 01063
Author(s):  
Larisa A. Neminuschaya ◽  
Natalia K. Eremets ◽  
Tatyana A. Skotnikova ◽  
Igor V. Pavlenko ◽  
Vladimir I. Eremets ◽  
...  

The paper deals with the results of assessing the intensity of PCV2 (porcine circovirus type 2) circulation in pigs of different age groups on pig farms in the Russian Federation. Serum samples of 128 pigs of different age groups from two pig farms in the Russian Federation were studied. As a result, specific antibodies to PCV2 were detected that proves virus circulation. Average titer of serum antibodies was 1:2020 for weaning piglets, 40 d.a. (days of age), in prenursery piglets of the age of 20 days - 1:3120; in replacement gilts of the age of 175 days - 1: 5124; in feeding pigs of the age of 180 days - 1:5300. In female pigs, the percentage of seroprevalence was 95 %. With advancing ageing of pigs, the level of antibody titer to PCV2 was increasing that proves the animals were infected after the decrease of colostral antibody level below protective one.


2018 ◽  
Vol 63 (No. 8) ◽  
pp. 358-366
Author(s):  
LL Zheng ◽  
XH Jin ◽  
FS Wei ◽  
CQ Wang ◽  
HY Chen ◽  
...  

Porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2 can cause reproductive failure in pigs, and swine are often simultaneously infected by combinations of the three viruses. We here report the development of a SYBR Green I-based multiplex real time PCR assay for simultaneous detection of porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2. Three pairs of specific primers were designed for the porcine parvovirus-VP2, porcine pseudorabies virus-gH and porcine circovirus type 2-ORF2 genes. Viral genomes were identified based on their distinctive melting temperatures in singleplex PCR reactions. The melting temperature was 74.5 °C for the 313 bp amplicon of porcine parvovirus-VP2 gene, 87.5 °C for the 355 bp amplicon of porcine pseudorabies virus-gH gene and 80.5 °C for the 171 bp amplicon of the porcine circovirus type 2-ORF2 gene, respectively. The detection limit of the method ranged from 0.01–0.03 TCID<sub>50</sub>/ml for the three viruses. In addition, porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2 viral loads were measured in 100 field samples, and the result showed that the concordance between real-time PCR and conventional PCR was 60.42%. The sensitivity and specificity of real-time PCR were 100% and 100%, while those of conventional PCR were 40.83% and 72.22%, respectively.


Viruses ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1135 ◽  
Author(s):  
Aleksandra Woźniak ◽  
Dagmara Miłek ◽  
Piotr Matyba ◽  
Tomasz Stadejek

Porcine circovirus type 2 (PCV2) is a globally spread pathogen controlled with generally highly efficacious vaccination protocols. In order to compare PCV2 detection profiles in farms with different vaccination statuses, serum (359) and fecal pools (351) and oral fluids (209) from four farms that do not vaccinate against PCV2 (NON-VAC) and from 22 farms that do vaccinate (VAC) were tested with quantitative real-time PCR. Additionally, nucleotide sequences of ORF2 of the virus were obtained from selected samples. Three genotypes, PCV2a, PCV2b, and PCV2d, were detected. Significant differences (p < 0.05) in PCV2 prevalence and quantities between the VAC and NON-VAC farms were evident. In five VAC farms, no viremia or shedding in feces was detected. On the other hand, in four VAC farms, the results were very similar to those from NON-VAC farms. No significant difference in PCV2 prevalence in oral fluids was observed between VAC and NON-VAC farms. An examination of viremia can be recommended for the detection of vaccination efficacy issues. The median of the PCV2 viral loads >6.0 log10 copies/mL in pooled sera from the vaccinated population should be considered a very strong indication that the vaccination protocol needs revision.


2012 ◽  
Vol 179 (2) ◽  
pp. 311-315 ◽  
Author(s):  
Michaela Vlasakova ◽  
Anna Jackova ◽  
Valeria Leskova ◽  
Stefan Vilcek

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