The objective of this study was to compare the inflammatory response within the abdominal cavity between three surgical methods. The study comprised 45 cows with left displacement of the abomasum, which were allocated into three groups (n = 15). Right flank laparotomy and omentopexy (group R), left flank laparotomy and omentopexy (group L), and laparoscopic abomasopexy (group J) have been applied. Laparoscopic abomasopexy was the only technique that requires perforation of the abomasal wall. Blood and peritoneal fluid (PF) samples were obtained before, and on days 1, 2 and 3 after surgery. Macroscopic and microscopic evaluation of PF were performed. Cytological and biochemical parameters were analysed in blood and PF. No bacteria were present in PF after surgery. The number of PF leukocytes increased in all groups on day 1 after surgery with the highest value after laparoscopy (median, 1st quartile, 3rd quartile, R: 13.1, 6.4, 16.0; L: 13.6, 9.9, 17.4; J: 33.7, 21.1, 46.9 G/l). Laparotomy resulted in an increase of blood and PF CK on day 1 after surgery, whereas, laparoscopy caused an increased PF CK only. All groups had elevated PF D-dimer concentrations before surgery, with further increase in groups R and L on day 1 after surgery.