This study aimed to evaluate the parameters of renal and hepatic functions in horses submitted to an experimental model of intestinal obstruction. Twenty-four animals were distributed into four different groups: instrumented control (GI), duodenum obstruction (GII), ileum obstruction (GIII) and large colon obstruction (GIV). Blood samples were collected one hour before the surgical procedure (T0); 3 hours after the obstruction/ischaemia (T3i); and 1, 3, 12, 24, 72 and 120 hours after the beginning of reperfusion/deobstruction for determination of the concentration of urea, creatinine, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase, albumin, glucose, fibrinogen and bilirrubin (total, direct and indirect). During obstructive period none significant alterations were observed in the biochemical parameters evaluated. After the unblocking procedure, the animals from GII and GIII presented an increase in aspartate aminotransferase, alkaline phosphatase, fibrinogen and total and direct bilirrubin values. However, these changes were not associated with clinical signs of liver damage and, at the end of the observation period their values were found within normal range. Considering the laboratory tests for the diagnosis of hepatic lesions lack specificity, it is recommended that such tests are performed concomitantly and in series.KEYWORDS: Acute abdomen, blood biomarkers, equines.