Canine parvovirus is a viral disease that infects dogs and various animal groups. In hemogram analysis, there is panleukopenia, lymphopenia, neutropenia, and less commonly monocytosis. In recent years, different hematological parameters have been used to evaluate bacterial, viral, and neoplastic disease severity and course. Among these, there are several studies on neutrophil/lymphocyte (NEU/LYM) and platelet/lymphocyte (PLT/LYM) ratios to evaluate the immune system response to inflammation in human and veterinary medicine due to their low cost and easy applicability. The cut-off index (COI) in automated analyzers and immunoassays is a qualitative test that does not give antigen concentration, but studies have shown that it indicates pathogen load. This study investigated the relationship between viral load and reticulocyte/lymphocyte (RET/LYM), NEU/LYM, and PLT/LYM ratios in dogs with parvoviral enteritis. A total of 120 dogs were included in the study: 60 dogs diagnosed with parvoviral enteritis formed the study group, while 60 clinically healthy dogs constituted the control group. Viral loads of dogs with parvoviral enteritis were measured by COI. Complete blood counts were measured of all the animals. RET/LYM, NEU/LYM, and PLT/LYM ratios were statistically significantly higher in the study group than in the control group. COI was significantly positively correlated with the RET/LYM and NEU/LYM ratios. These ratios were new candidates for easy-to-use, cost-effective, objective, and non-invasive prognostic markers in dogs with canine parvoviral enteritis. In addition, since there was a positive correlation between the COI, an indicator of pathogen load, and the RET/LYM and NEU/LYM ratios. It was concluded that these ratios would also play an important role in determining the disease severity.

To Cite This Article: Esin C 2025. Relationship between viral load and reticulocyte/lymphocyte, neutrophil/lymphocyte and platelet/lymphocyte ratios in dogs with parvoviral enteritis. Pak Vet J, 45(2): 834-842. http://dx.doi.org/10.29261/pakvetj/2025.179