Molecular epidemiology of Canine parvovirus shows CPV-2a genotype circulating in dogs from western India

Canine parvovirus (CPV) has emerged as an acute pathogen of young canine causing haemorrhagic enteritis and myocarditis. It is widely distributed and underreported in India. Therefore the study was conducted to type the CPV circulating in western Maharashtra. The faecal samples (n = 150) from clinically ill dogs showing diarrhoea and vomition were collected and subjected to haemagglutination (HA) with porcine RBC's. The DNA was extracted from the samples showing HA titres above 64 and subjected for amplification of VP2 gene fragment by PCR. The amplicons were subjected for restriction fragment length polymorphism (RFLP), sequencing and BEAST phylogenetic analysis. The results revealed 6% positivity by PCR. The RFLP results indicated single cleavage site for ApaLI and HinfI with an exception of two sites for HinfI. The nucleotide sequences showed nonfunctional nucleotide changes at different locations. The sequence analysis indicated that the nucleotide divergence within isolates under study was 0.00-0.42%, while the nucleotide homology was 99.58-100%. The most recent common ancestor was determined by molecular clock analysis using Bayesian methods. The sequence and phylogenetic analysis suggested the isolates as CPV-2a and KATN1 (KU866391, 2014) isolate from Tamilnadu, India as time to most recent common ancestor (TMRCA). The results revealed the circulating CPV in canines from western India as CPV2a genotype.