General anesthesia was achieved using a weight depending dose of 80 mg/kg body weight Ketamine and 5 mg/kg Xylazine®. Required level of narcosis for surgery was reached if flexor reflexes failed to appear. The abdomen was then shaved and prepared with alcohol and iodine solution. A 4 cm median laparotomy was performed to gain access to the abdominal cavity. In the optimized peritoneal adhesion model group (OPAM) (n = 10), the cecum was delivered and kept moist with a watery gauze swab whilst dry gauze was used to gently abrade the cecal peritoneum in a standard manner. Abrasion was repeated until removal of visceral peritoneum, occurring of sub-serosal bleeding, and creation of a homogenous surface of petechial hemorrhages over a 1 x 2 cm area. An 1 x 2 cm sized patch of parietal peritoneum with the underlying inner muscular layer was sharply resected of the right-lateral abdominal wall (Figure 1A). After replacing the cecum intra-abdominally, both defects were approximated with a 4/0 Prolene® suture to fix the mesentery of the ascending colon to the abdominal wall (Figure 1B). The group without suture fixation (WSFX) (n = 4) represents conventional adhesion models as cecum and abdominal wall, exactly injured as described above, were not approximated. In the sham-OPAM group (n = 5) only the approximating suture was placed without peritoneal injuries. In sham-WSFX group (n = 5) animals underwent only laparotomy without any injury and/or suturing. The abdomen was closed using two-layer closure technique by a consecutive suture.