Septicemia in large animals is one of the common causes of mortality with the difficulties of
early diagnosis. To diagnose sepsis in animals, clinical signs and blood cultures are
combined with hematological values, inflammatory biomarkers and serum biochemistry.
Biomarkers specific to sepsis, such as procalcitonin (PCT), have been the subject of recent
research in humans and animals. This study evaluated PCT concentration using enzymelinked immunosorbent assay (ELISA) in serum samples collected from 50 calves with
clinical septicemic disease and 20 healthy calves. PCT concentration was 66.86±0.15
pg/mL (25.4-140.2 pg/mL) in the control healthy group and 756.1±3.65 pg/mL (90.23-
2185 pg/mL) in the diseased group. The optimal cutoff value for distinction between
healthy and sick calves was 148.4 pg/mL. Using a receiver operator characteristic (ROC
curve) revealed the highest area under the curve (AUC) value of procalcitonin 0.99; 95%
confidence interval [CI]. ELISA procalcitonin test shows high diagnostic sensitivity,
specificity, and accuracy for diagnosis of septicemia, and the result emphasized the
importance of ELISA procalcitonin as a faster, more accurate, and metrically efficient
diagnosis for sepsis in calves.