Abstract Background Colic is a major cause of morbidity and mortality in horses, with oxidative stress implicated in its pathophysiology. Hypothesis/Objectives Evaluate biomarkers (BIOs) of oxidative stress and antioxidant defense in healthy horses and those with non-strangulating colic (NSC) and strangulating colic (SC) and assess correlations with survival. Animals Seventy-one adult horses: 10 healthy and 61 colic-affected (42 NSC, 19 SC) admitted to 3 veterinary teaching hospitals. Methods Prospective, multicenter cohort study. Blood samples were collected at admission (T0) and up to 96 h post-admission. Biomarkers measured included arylesterase (AREase), paraoxonase (POase), lipid peroxidation (LPO), superoxide dismutase (SOD), butyrylcholinesterase, total antioxidant capacity (TAC), glutathione S-transferase (GST), and glutathione peroxidase (GPx). Data were analyzed using nonparametric statistics and generalized linear mixed models. Results Compared with healthy horses, colic-affected horses had higher AREase (P = .01), GST (P = .001), and GPx (P = .001), and lower POase (P .001) and TAC (P = .02). Survival was associated with higher AREase (coefficient coef. 106.65 kU/L; 95% confidence interval CI, 24.70-188.60; P = .01), lower SOD (coef. −0.38 U/mL; 95%CI, −0.76 to −0.06; P = .03), and lower TAC (coef. −3.37 μmol/mL; 95%CI, −5.49 to −1.25; P = .01). Colic type also influenced results, with NSC (vs SC) associated with lower LPO (coef. −1.24 malondialdehyde MDA/μL; 95%CI, −2.81 to −0.32; P = .01), higher SOD (coef. 0.42; 95%CI, 0.03-0.81; P = .04), and higher TAC (coef. 1.21; 95%CI, 0.10-2.98; P = .04). Conclusions and clinical importance Results emphasize the association between oxidative stress BIOs and colic in horses, suggesting that specific BIOs, particularly AREase, may have prognostic utility.
Bindi et al. (2026) studied this question.