The Use of Abdominal Ultrasound to Improve the Cryptorchidectomy of Pigs

Simple Summary Cryptorchidism is the failure of one or both the testes to descend in the scrotum. In pigs, the incidence of cryptorchidism varies from 4% to 12%, and the most frequent localisation of retained testes is the abdominal region. In other species, transabdominal ultrasound is the most reliable diagnostic tool to localize the retained testis. This study aimed to evaluate the value of ultrasound in correctly identifying the location of retained testes, to improve the cryptorchidectomy in pigs. The ultrasound examination reduced the duration of anaesthesia, surgery, and postoperative pain. Indeed, the technique used is safe, effective, and rapid. To locate the testis, it should recognise the echo structure of the testicle and the mediastinum is well always recognisable for its hyperechogenicity. The routine use of the ultrasound examination is considered a useful alternative before the cryptorchidectomy in the pig because it allows the exact location of the retained testicle, ensuring reduced manipulation of the viscera. This study aimed to describe a technique to locate retained testes in pigs by means of ultrasound examination and thereafter proceed with cryptorchidectomy. Fifty-two monolateral cryptorchid pigs were enrolled. After anaesthesia, 42 pigs (Group U) underwent ultrasound examination before cryptorchidectomy, and 10 pigs (Group C) were used as control group without ultrasonography. The total duration of anaesthesia, ultrasound examination, and surgery was evaluated. In 10 pigs of Group U and 10 pigs of Group C, the heart rate (HR), respiratory rate (RR), and body temperature (T) were monitored to assess intraoperative pain response. An operator used the Piglet Grimace Scale (PGS) to assess postoperative pain. In Group U, the total time required for anaesthesia and surgery was less than Group C. No intra- or postoperative complications were reported in both groups. For HR, RR, and T, no statistically significant differences were observed. During the postoperative pain assessment, the highest pain scores were recorded at T6 (6 h after surgery). Ultrasound examination was found to be a valid technique for locating the retained testis in the abdomen in cryptorchid pigs and to reduce the duration of the surgery.