Serological and Nucleocapsid Gene Based Molecular Characterization of Canine Distemper Virus (CDV) Isolated from Dogs of Southern Gujarat, India

Abstract

Background: The present study was undertaken to diagnose and characterize canine distemper virus (CDV) isolated from dogs of southern Gujarat, India. CDV is lethal disease of canines and felines. Total of 40 different samples were collected from 18 suspected stray dogs having different clinical signs which were processed for diagnosis and characterization of CDV.Methods: All samples were processed by employing different methods like, Immunochromatography based lateral flow test (LFA), IgG based indirect enzyme linked immunosorbent assay (i-ELISA), one step RT-PCR, nested one step RT-PCR and virus isolation in MDCK cell line. Restriction endonuclease (RE) analysis was used to characterize CDV Nucleocapsid (N) gene. Conclusion: Only 04 samples (02 nasal and 02 ocular swabs) of 02 dogs found positive for LFA, while 14 serum samples out of 17 samples of 18 dogs found positive for IgG antibody. As all dogs were unvaccinated, serum samples found positive in IgG based ELISA considered for confirmative positive for CDV infection. Whereas 13 samples of 10 dogs found positive for one step RT-PCR and nested one step RT-PCR. In RE digestion, characteristic two bands were found. All representative CDV positive samples of 10 dogs showed characteristic cytopathic effect in MDCK cell line. On age group wise percent positivity was found 71.42 % (05/07) in 0 - ≤6 months, while 77.77% (07/09) in 6- ≤12 months of age group, whereas, both samples were found positive in 12 months and above group. Overall 77.77% (14/18) dogs found positive for CDV infection. To the best of our knowledge, this is the first report on study of CDV infection in dogs from Gujarat state, India.