Molecular characterisation of viral pathogens associated with respiratory and gastrointestinal infections in dogs in Türkiye – preliminary study

Abstract Introduction Canine viral infections cause significant morbidity and mortality in dogs worldwide. This study aimed to investigate the presence of canine adenovirus (CAdV), canine parvovirus (CPV), canine distemper virus (CDV) and canine herpesvirus (CHV) at the molecular level. Material and Methods A total of 68 paired nasal secretion and blood samples were obtained from 34 dogs, and 93 faecal samples were collected, each from a single dog. All sampled animals showed clinical signs of respiratory or gastrointestinal disorders. They came from five different provinces of Türkiye. The samples were tested by PCR and selected strains were sequenced. Results While no CAdV was detected in the PCR analyses, CPV gene amplification was achieved in 60.2% (56/93) of the DNA extracted from faecal samples, CDV genes were amplified in 11.8% (4/34) of the genetic material extracted from nasal swabs, and CHV genes were amplified in 14.7% (5/34). One nasal swab sample showed a co-infection with CDV and CHV, but the corresponding blood sample did not. Phylogenetic analyses of the viral strains were conducted; among CPV strains, CPV-2b and CPV-2c variants were identified and found to share high genetic similarity with strains of Asian and African origin. The CDV strains were closely related to European strains, while the CHV strains exhibited genetic diversity and matched strains isolated worldwide. No statistically significant association was found between viral infections and the sex or age of the animals. Conclusion These findings provide insight into the molecular epidemiology of viral infections in dogs in Türkiye and reveal that local strains are phylogenetically closely related to globally circulating strains.