Diagnosis and characterization of canine parvovirus-2 affecting canines of south Gujarat, India

Abstract

The present study was carried out in the region of South Gujarat, India, to determine the prevalence and predisposing factors of canine parvovirus-2 (CPV-2) infection in acute gastroenteritis of pups. Further, haemagglutination (HA) test, enzyme linked immunosorbent assay (ELISA), polymerase chain reaction (PCR) and rapid immunochromatography test were compared for diagnosis and prevalent CPV-2 types were ascertained. A total of 73 diarrhoea samples were collected and out of those 32, 33 and 35 were found positive via HA, ELISA and PCR, respectively. In rapid test, 26/52 samples were found positive. Among different age-groups, 11/24 and 13/21 animals were positive in pups aged 4-8 and 8-12 weeks, respectively. All but one (34/35) positive samples were from unvaccinated animals. Labrador was found to be the most susceptible breed (n = 13) to infection. Considering PCR as the best test, 47.94% (35/73) prevalence of CPV was recorded. Among PCR positive samples, 3 and 32 belonged to type CPV-2a and CPV-2b, respectively. Type CPV-2c was not detected among the examined samples. Sequencing analysis of 9/10 CPV-2b isolates revealed single nucleotide polymorphism (SNP) (A-G) at position 4106 (alanine to threonine) and suggested the occurrence of mutant, new CPV-2b in this area. As other major pathogen canine coronavirus was detected in 7/38 CPV negative samples. Conclusively, CPV-2 infection was detected in 47.97% cases of AGE of pups which warrants search for other pathogens in the diagnostic procedure. This work is among the few recent reports which depict the occurrence of a novel mutant (new CPV-2b) in India.