Among all candidate variables (CRP, albumin, CAR, and age), CRP emerged as the only statistically significant predictor of SIRS classification (p < 0.001), highlighting its central role in the systemic inflammatory response associated with parvoviral infection The model established an optimal split at 1.9 mg/dL, effectively distinguishing dogs classified as SIRS-negative from those classified as SIRS-positive. The gene discussed is CRP; the disease is systemic inflammatory response syndrome.