Development of cost-effective quantitative PCR method for parallel detection of porcine circovirus2 and porcine parvovirus in perspective of North-eastern India.

Abstract

Pig farming performs as an intricate part in the socio-economic situation in the north-eastern region of India. This region contributes 38% (3.95 million) of total pigs in India. In spite of this, the region unables to flourish as an enterprise as per the expectation due to a low productivity rate. Porcine infectious pathogens like porcine cirovirus2 (PCV2) and porcine parvovirus (PPV) have a direct economic impact on pig farming through slow growth rate, abortion, and mortality and ultimately maximize the production cost by increasing the usage of antibiotic or antiviral drugs. The veterinary diagnostic infrastructure is a fundamental aspect of the development of livestock status by rapid and effective detection of pathogens. Quantitative PCR (qPCR) is a precise and fast-track technique used for the routine diagnostic method. Hence, we developed a highly precise and comparatively cost-effective SYBR Green reporter dye-based qPCR assay for parallel identification of PCV2 and PPV. In the present assay, the correlation coefficient (R2) value was 0.99, and 10 copies of the gene/μl were the least limit of detection (LOD) concerning both viruses. Melt curve analysis of this study represented PCV2-specific melt curve (Tm) at 81.2 °C and PPV-specific melt curve (Tm) at 73.5 °C. Therefore, the assay easily differentiates the true positive amplicons of PCV2 and PPV through specific Tm values. Among the 50 field samples, 26 (52%) samples were PCV2 positive, 18 (36%) samples PPV positive, and 11 (22%) samples were co-infected of both the viruses. This method is cost-effective, precise, and sensitive to diagnose the concurrent or individual infection of the PCV2 and PPV in the pig. Hence, considering the impact of pig farming in the north-eastern part of the country, the present assay gives an unprecedented achievement in disease diagnosis.