sybr-green-i and Swine-Diseases

In this study, we developed a SYBR Green I real-time PCR method for the rapid and sensitive detection of novel porcine parvovirus 7 (PPV7). Specific primers were designed based on the highly conserved region within the Capsid gene of PPV7. The established method was 1,000 times more sensitive than the conventional PCR method and had a detection limit of 35.6 copies. This method was specific and had no cross-reactions with PCV2, PCV3, PRV, PEDV, PPV1, and PPV6. Experiments testing the intra and interassay precision demonstrated a high reproducibility. Testing the newly established method with 200 clinical samples revealed a detection rate up to 17.5% higher than that of the conventional PCR assay. The established method could provide technical support for clinical diagnosis and epidemiological investigation of PPV7.

Topics: Animals; Benzothiazoles; Diamines; Parvoviridae Infections; Parvovirus, Porcine; Quinolines; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Swine; Swine Diseases

Topics: Animals; Benzothiazoles; China; Circoviridae Infections; Circovirus; Coinfection; Diamines; Genome, Viral; Herpesvirus 1, Suid; Limit of Detection; Multiplex Polymerase Chain Reaction; Pseudorabies; Quinolines; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Species Specificity; Swine; Swine Diseases; Transition Temperature

Porcine parvovirus (PPV) is one of the major causes of reproductive pig disease. Due to its serious nature, wide spread and consequent great damage to the swine industry, an effective, rapid and convenient method for its detection is needed. A loop-mediated isothermal amplification (LAMP) assay was established to detect PPV infection. Two pairs of primers were specifically designed to recognize the six different sequences of open reading frame1 (ORF1) gene. The optimized LAMP program was as follows: 50 min at 59 °C followed by 3 min at 80 °C.The amplified products were analyzed both by visual inspection after staining with SYBR Green I dye and by conventional agarose gel electrophoresis. Both methods showed the same sensitivity. The limit of detection (LOD) for PPV by LAMP was 10 copies, which is 100-fold lower than conventional PCR. Our LAMP assay did not cross-react with other viruses. We used the established LAMP system to test 1100 field samples and detected 660 positives. The LAMP detection method for PPV represents a visual, sensitive and rapid assay which can detect the virus in the field, offering an attractive alternative for the PPV detection methods currently in use.

Topics: Animals; Benzothiazoles; Diamines; Molecular Diagnostic Techniques; Nucleic Acid Amplification Techniques; Parvoviridae Infections; Parvovirus, Porcine; Point-of-Care Systems; Quinolines; Sensitivity and Specificity; Swine; Swine Diseases; Temperature

In this study, a SYBR Green-based real-time quantitative polymerase chain reaction (qPCR) assay was developed for rapid detection of porcine parvovirus (PPV) 6. Primer pairs targeting the conserved regions of PPV6 Capsid gene were designed. Sensitivity analyses revealed the lowest detection limit of the SYBR Green-based real-time PCR assay to be 47.8 copies/μL, which indicated it was 1000 times higher than that found in the conventional PCR investigations. This assay was specific and showed no cross-species amplification with other six porcine viruses. The assay demonstrated high repeatability and reproducibility; the intra- and inter-assay coefficients of variation were 0.79% and 0.42%, respectively. The positive detection rates of 180 clinical samples with SYBR Green-based real-time PCR and conventional PCR were 12.22% (22/180) and 4.44% (8/180), respectively. Our method is sensitive, specific, and reproducible. The use of SYBR Green-based real-time PCR may be suitable for the clinical detection and epidemiological investigation of PPV6.

Topics: Animals; Benzothiazoles; Diamines; Parvoviridae Infections; Parvovirus, Porcine; Quinolines; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Swine; Swine Diseases

Topics: Animals; Benzothiazoles; China; Circoviridae Infections; Circovirus; Coinfection; Diamines; Quinolines; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Swine; Swine Diseases

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a novel coronavirus which was associated with severe diarrhea disease in pigs. SADS-CoV was first detected and identified as the causative agent of a devastating swine disease outbreak in southern China in 2017. Routine monitoring and early detection of the source of infection is therefore integral to the prevention and control of SADS-CoV infection. In this study, a SYBR green-based real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) technique was established for rapid detection and monitoring of this emerging virus. Specific primers were designed based on the conserved region within the M gene of the viral genome. The lowest detection limit of the RT-qPCR assay was 10 copies/μL. This assay was specific and had no cross-reaction with other 11 swine viruses. The positive rate of 84 clinical samples for the SYBR green-based RT-qPCR and the conventional RT-PCR was 73.81% (62/84) and 53.57% (45/84), respectively. These results demonstrated that the SYBR green-based RT-qPCR technique was an effectively diagnostic method with higher sensitivity than probe-based RT-qPCR and gel-based RT-PCR for detection and epidemiological investigations of SADS-CoV.

Topics: Alphacoronavirus; Animals; Benzothiazoles; China; Coronavirus Infections; Diamines; DNA Primers; Organic Chemicals; Quinolines; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Sensitivity and Specificity; Staining and Labeling; Swine; Swine Diseases; Time Factors

Porcine deltacoronavirus (PDCoV) is a newly discovered coronavirus, which belongs to the family Coronaviridae. It causes watery diarrhea, vomiting, and dehydration in newborn piglets. A sensitive RT-PCR method is urgently required to detect PDCoV infection. In this study, we developed and evaluated a conventional RT-PCR assay and a SYBR green-based real-time RT-PCR assay that targeted the PDCoV

Topics: Animals; Benzothiazoles; Coronavirus; Diamines; Limit of Detection; Organic Chemicals; Quinolines; Reproducibility of Results; Reverse Transcriptase Polymerase Chain Reaction; Sensitivity and Specificity; Swine; Swine Diseases

Porcine epidemic diarrhea (PED) caused by porcine epidemic diarrhea virus (PEDV) is a highly contagious intestinal disease, resulting in substantial economic losses to the swine industry worldwide. In this study, three assays, namely a conventional reverse transcription-polymerase chain reaction (RT-PCR), a SYBR Green I real-time RT-PCR and a TaqMan real-time RT-PCR targeting the highly conserved M gene of PEDV, were developed and evaluated. Then, the analytical specificity, sensitivity and reproducibility of these assays were determined and compared. The TaqMan real-time RT-PCR was 100-fold and 10,000-fold more sensitive than that of the SYBR Green I real-time RT-PCR and the conventional RT-PCR, respectively. The analytical sensitivity of TaqMan real-time RT-PCR was 10 copies/μl of target gene and no cross amplification with other viruses tested was observed. With the features of high specificity, sensitivity, and reproducibility, the TaqMan real-time RT-PCR established in this study could be a useful tool for clinical diagnosis, epidemiological surveys and outbreak investigations of PED.

Topics: Animals; Benzothiazoles; Coronavirus Infections; Diamines; Organic Chemicals; Porcine epidemic diarrhea virus; Quinolines; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Swine; Swine Diseases

The development of a SYBR Green-based duplex real-time PCR is described for simultaneous detection of porcine parvovirus (PPV) and porcine circovirus type 2 (PCV-2) genomes. Viral genomes were identified in the same sample by their distinctive melting temperature (T(m)) which is 77.5°C for PPV VP2 313bp amplicon and 82.3°C for PCV-2 ORF2 171bp amplicon, respectively. The detection limit of the method was 0.01TCID(50)/mL for PPV and PCV-2, about 10 times more sensitive than conventional PCR. In addition, PPV and PCV-2 viral load were measured in 126 field samples, confirming the sensitivity and specificity, and the result showed that 70/126 samples were positive for PPV and 92/126 samples were positive for PCV2 by the duplex real-time PCR. This method may be a useful alternative rapid and reliable method for the detection of PPV/PCV-2 co-infection.

Topics: Animals; Benzothiazoles; Circoviridae Infections; Circovirus; Coinfection; Diamines; DNA Primers; DNA, Viral; Limit of Detection; Nucleic Acid Denaturation; Organic Chemicals; Parvoviridae Infections; Parvovirus, Porcine; Quinolines; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity; Swine; Swine Diseases; Viral Load

Multiple viral infections are common in pigs under intensive production conditions. All five of the viruses included in this study are associated with multifactorial diseases that cause significant economic losses in swine farming worldwide. The development is described of a novel multiple real-time PCR system based on the use of SYBR Green I that allows the simultaneous detection and differentiation of porcine circovirus 2 (PCV-2), porcine parvovirus (PPV), pseudorabies virus (PRV) and Torque teno sus virus species 1 and 2 (TTSuV1 and TTSuV2) in pigs. The method was able to distinguish between all five viral agents, and tests of other DNA viruses proved the specificity of the system. The multiple real-time PCR system was sensitive, as the limits of detection ranged from 3.65×10(3) to 5.04×10(3) copies of DNA template per reaction. The coefficients of variation were low for both intra-assay and inter-assay variability. In addition, the results of the multiple real-time PCR system tests were 100% consistent with previous results based on specific PCR assay testing of field samples. This method could be a useful tool for epidemiological studies and disease management.

Topics: Animals; Benzothiazoles; Diamines; DNA Primers; DNA Virus Infections; DNA Viruses; DNA, Viral; Molecular Diagnostic Techniques; Molecular Sequence Data; Multiplex Polymerase Chain Reaction; Organic Chemicals; Quinolines; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity; Sequence Analysis, DNA; Staining and Labeling; Swine; Swine Diseases; Virology

Porcine circovirus type 2 (PCV2) is the primary causative agent of the emerging swine disease known as postweaning multisystemic wasting syndrome (PMWS). Nowadays, polymerase chain reaction (PCR) is still the most widespread technique in pathogen detection. Loop-mediated isothermal amplification (LAMP), a novel nucleic acid amplification method developed in 2000, will possibly replace PCR in the field of detection. To establish a LAMP method for rapid detection of PCV2, two pairs of primers were designed specially from the open reading frame 2 (ORF2) sequences of PCV2. A LAMP method for rapid detection of PCV2 was established. To compare with PCR, sensitivity and specificity of LAMP were evaluated using the optimized reaction system. The LAMP products could be determined by agarose gel electrophoresis or adding SYBR Green I dye.. The amplification of LAMP could be obtained at 63°C for 60 min. The detection limit was nearly 1 copy of DNA plasmid, more sensitive than PCR. There was no cross-reaction with porcine circovirus type 1 (PCV1), porcine pseudorabies virus (PRV) and porcine parvovirus (PPV) under the same conditions.. LAMP is an useful rapid detection method with high sensitivity and specificity for PCV2.

Topics: Animals; Benzothiazoles; Circoviridae Infections; Circovirus; Diamines; DNA Primers; Electrophoresis, Agar Gel; Nucleic Acid Amplification Techniques; Open Reading Frames; Organic Chemicals; Quinolines; Sensitivity and Specificity; Staining and Labeling; Swine; Swine Diseases; Virology

Porcine Torque teno virus (TTV), a single-stranded circular DNA virus, has been incriminated in swine diseases recently. Multiple infection with porcine TTV species 1 (PTTV1) and species 2 (PTTV2), each consisting of two types (PTTV1a and 1b) or subtypes (PTTV2b and 2c), in a single pig had been reported by our group previously. The present study described three novel assays for quantitation and differential detection of porcine TTV. First, we developed two SYBR green-based real-time PCR assays to quantify viral loads of two porcine TTV species, respectively. The PTTV1- and PTTV2-specific real-time PCR primer sequences were selected to target conserved regions identified by multiple alignments of ten available porcine TTV full-length genomes. Furthermore, by coupling the two singleplex PCR assays, a duplex real-time PCR assay followed by melting curve analysis was established for simultaneous detection and differentiation of PTTV1 and PTTV2. In addition, a type-specific duplex nested PCR was also developed to simultaneously detect and distinguish between the two types, PTTV1a and 1b, in PTTV1 species. These assays provide rapid and practical tools for molecular diagnosis of species- or type-specific porcine TTV.

Topics: Animals; Base Sequence; Benzothiazoles; Diamines; DNA Primers; DNA Virus Infections; DNA, Viral; Molecular Diagnostic Techniques; Organic Chemicals; Polymerase Chain Reaction; Quinolines; Sensitivity and Specificity; Sequence Alignment; Staining and Labeling; Swine; Swine Diseases; Torque teno virus

The novel influenza A(H1N1) virus that emerged recently in Mexico has spread rapidly to many countries and initiated a human pandemic. It would be interesting to determine whether the virus has existed in, or will spread to, the swine population. However, it is difficult to differentiate the virus from some swine influenza viruses. In this study, a SYBR Green I real-time RT-PCR assay was designed for detection and differentiation of influenza A(H1N1) virus from some swine influenza viruses, by comparing the amplification of two pairs of primers corresponding to influenza A(H1N1) virus and some swine influenza viruses, respectively. The assay was evaluated using online analysis, identified influenza viruses and clinical samples. The results indicated that the assay has high sensitivity and specificity to detect influenza A(H1N1) virus, and is able to differentiate it from some swine influenza viruses. This, in turn, could provide essential epidemiological information for risk analysis and decision making in combating the disease, and stimulate research to differentiate pathogens similar to each other using the same method.

Topics: Animals; Benzothiazoles; Diamines; DNA Primers; Influenza A Virus, H1N1 Subtype; Organic Chemicals; Orthomyxoviridae Infections; Quinolines; Reverse Transcriptase Polymerase Chain Reaction; Sensitivity and Specificity; Swine; Swine Diseases

This report describes a real-time polymerase chain reaction assay with SYBR Green for detection of a broad range of porcine parvoviruses (PPV) and accurate virus quantification in porcine tissues. The assay targets the VP2 gene of PPV and the porcine genomic c-myc gene for normalization. The detection limit of the SYBR Green reaction was shown to be equivalent to 6 x 10(0) to 6 x 10(1) PPV copies/reaction and the overall detection limit equivalent to 0.1 TCID(50)/100 microl. The assay was linear over a 10(7) dilution range of template concentrations. Other porcine pathogens involved in reproductive disorders such as porcine circovirus 2 (PCV-2), porcine reproductive and respiratory virus (PRRSV), Aujeszky's disease virus (PRV) and other parvoviruses such as feline parvovirus (FPV), canine parvovirus (CPV), minute virus of canines (MVC) and a human parvovirus (B19) were not detected by this assay.

Topics: Animals; Animals, Wild; Benzothiazoles; Capsid Proteins; Cell Line; Diamines; DNA Primers; Fetus; Genes, myc; Genes, Viral; Organic Chemicals; Parvoviridae Infections; Parvovirus, Porcine; Quinolines; Reverse Transcriptase Polymerase Chain Reaction; Sensitivity and Specificity; Swine; Swine Diseases; Viral Plaque Assay; Viscera