Equine castration in Sweden: a retrospective study of postoperative complications across field and hospital practices

Background This retrospective study describes and compares the surgical techniques and medical protocols used for castration of male horses in Swedish ambulatory practices (Field group) and in Swedish equine hospitals (Hospital group). Data on patient characteristics, perioperative medical protocols, surgical techniques and postoperative complications were collected as documented in patient records of both groups. Descriptive statistics, univariable and multivariable analyses were used to evaluate factors associated with postoperative complication. Results The overall complication rate was 35% in the Field group and 13% in the Hospital group. This difference remained significant after adjusting for age and breed in a multivariable analysis (OR 4.5; CI 3.18–6.36). In the Field group 511/521 horses (98%) were castrated standing using sedation and local analgesia, incisions were left un-sutured in all horses (100%). The surgical technique was described in 230/521 records (44%), the open technique was used in 194/230 horses (84%) and the half-closed technique was used in 36/230 horses (16%). Complication and surgical site infection were associated with higher odds in horses that did not receive perioperative antimicrobial prophylaxis (OR 1.5; CI 1.01–2.36 and OR 1.7; CI 1.08–2.82 respectively). In the Hospital group, 554 stallions were castrated under general anaesthesia, and the incisions were sutured in 473/554 horses (85%). The closed technique was used in 503/554 horses (91%) and the half-closed was used in 51/554 (9%). Perioperative antimicrobial prophylaxis was administered to all horses in the Hospital group. Postoperative antimicrobial prophylaxis did not decrease the odds of surgical site infection in any of the groups. Conclusions In Sweden, standing, open castration with un-sutured incisions was preferred in ambulatory practice, whereas a closed, sutured technique dominated in the hospitals. Field castration was associated with a substantially higher odds of postoperative complications, compared with hospital-based castrations performed under general anaesthesia. These findings provide locally relevant evidence to guide clinical decision-making and antimicrobial stewardship and may contribute to the ethical discussion regarding the use of standing castration when alternatives are feasible.