Diagnostic performance of specific oxidative stress biomarkers, acute phase proteins, and certain trace elements in different severities of equine colic.

Sixty-one horses were included in this study and classified into three groups based on the severity of colic, assessed by heart rate, oral mucous membrane color, and abdominal distension. The groups consisted of a strangulating colic (SC) group (n=21), a non-strangulating colic (NC) group (n=20), and a control group (n=20) of randomly selected healthy horses without colic. Serum concentrations of tumor necrosis factor α (TNFα), haptoglobin (Hp), nitric oxide (NO), malondialdehyde (MDA), zinc, iron, and copper were measured in all horses. Receiver operating characteristic (ROC) analysis was conducted to assess and compare the diagnostic performance of the analytes in terms of sensitivity, specificity, and area under the curve (AUC). TNFα demonstrated the highest diagnostic accuracy for non-strangulating colic at a cutoff value of >24 mg/l, with 100% sensitivity, 95% specificity, and an AUC of 0.996. For strangulating colic, TNFα also exhibited the best diagnostic performance at a cutoff value of >33 mg/l, achieving 100% sensitivity and specificity with an AUC of 1.00. Haptoglobin followed with a cutoff value of >52 µg/l, showing 95% sensitivity, 75% specificity, and an AUC of 0.898. This study provides new insights into the diagnostic performance of TNFα for detecting non-strangulating colic and TNFα and haptoglobin for diagnosing strangulating intestinal conditions in horses with colic.