Detection and genetic characterization of porcine circovirus 3 (PCV3) in pigs in India

Porcine circovirus type 3 (PCV3), a novel circovirus, has been reported recently from major swine growing countries globally, and the virus is associated with diseases like porcine dermatitis, nephropathy syndrome and reproductive failure. This report describes the identification of PCV3 associated with reproductive failure in sows and piglet mortality and circulation of the virus in healthy pigs in India. The pathological changes in various tissues from stillborn piglet and characterization of the virus genomes were reported. The genome sequences of Indian PCV3 strains showed 91.4%-99.8% nucleotide identity with other sequences of PCV3 strains circulating worldwide. The phylogenetic analysis showed clustering of Indian strains into a separate group with the isolate from USA (MN/2016) under PCV3a genotype. The results confirmed the circulation of PCV3 in Indian pigs and its association with clinical cases. This study speculates emergence of PCV3 as an important pig pathogen in the country, which warrants the thorough investigation on PCV3 epidemiology, pathogenesis and to implement the control measures.