Methods for Castrating Male Xiang Pigs in Xiang Pig Farming

Castration of Xiang Pigs. For any male or female Xiang pigs not kept for breeding, in order to make their temperament docile, facilitate group raising and improve meat quality, castration (neutering) surgery can generally be performed between 2.5 and 3 months of age.

① Castration methods for male Xiang pigs. Castration of male Xiang pigs should generally be done early rather than late, and the surgery can be performed between 15 and 30 days after weaning. Castrating at too young an age hinders normal growth and development; castrating at too old an age increases the difficulty of the surgery. After 15 days post-weaning, Xiang pigs have basically adapted to the new environment, and a day with clear weather and no strong wind can be chosen for the surgery.

Before the castration surgery, a health check must be performed on the Xiang pig, mainly measuring body temperature, respiration, heart rate, and whether there are any abnormal changes in the external genitalia. If poor health or existing illness is found, the castration surgery should temporarily not be performed. Generally, feeding should be stopped for half a day before castration; when necessary, 1000-5000 units of tetanus antitoxin should be injected after castration. Penicillin 50,000-100,000 units should also be prepared and sprinkled on the castration wound. Surgical instruments generally include 1 scalpel, 2 hemostatic forceps, 1 pair of scissors, 1 small tweezers, No. 4 suturing thread, etc. Before surgery, the surgical instruments should be soaked in alcohol solution for half an hour, or boiled for half an hour. In addition, 3-4 pieces of sterilized gauze should be prepared.

To reduce pain in the Xiang pig, ketamine can be used for anesthesia at a dose of 5-15 mg per kg of body weight; the drug takes effect 3-5 minutes after intramuscular injection. Sodium thiopental can also be used at a dose of 20 mg per kg of body weight, prepared with sterilized distilled water into a 25% solution for intravenous injection. Before surgery, the hair on the scrotum and its surroundings should be carefully clipped, then disinfected with 2% iodine tincture, and then wiped with 75% alcohol.

The surgery is generally completed by two people working together, one operating and the other assisting. The anesthetized Xiang pig is restrained lying on its side, and a piece of sterilized gauze (cut open about 4-8 cm from the middle) is used as a surgical drape to cover the perineal area, exposing the scrotum. The surgery can use the intratunical castration method: fix one testicle with the thumb and index finger of the left hand so that the scrotal skin is stretched tight. Hold the scalpel in the right hand, cut once along the longitudinal axis of the testicle and parallel to the raphe line, opening the scrotum and tunica vaginalis communis about 2-3 cm, and squeeze out the testicle; cut open the scrotal ligament, then separate the testicular mesentery, push the scrotum and tunica vaginalis communis toward the abdominal wall to expose the spermatic cord, then ligate with thread using a double single knot; pull the tail thread and cut the spermatic cord about 0.3 cm after the knot; when no bleeding is observed, disinfect the cut end with 2% iodine tincture, then cut the tail thread, and the spermatic cord retracts. Use the same method to ligate, cut and disinfect the spermatic cord on the other side, then sprinkle the prepared antibacterial drug into the scrotal wound, remove the surgical drape, and disinfect locally. After surgery, when the anesthesia has worn off and the Xiang pig is fully awake, give fresh drinking water, and after 2-3 hours, give food, but the amount fed should not be too much, and then gradually restore the normal amount. After surgery, the wound surface should be kept dry; generally after 6-7 days, the scrotum shrinks and the wound heals. If 2-3 days after surgery there is local hard swelling accompanied by discharge, tenderness on touch, elevated body temperature and other reactions, timely diagnosis and treatment should be given. When local infection occurs, antibiotic treatment can be used.

② Ovary removal method for female Xiang pigs. The preparation work for ovary removal in female Xiang pigs is basically the same as for castration of male Xiang pigs, only the surgical site is different. Place the anesthetized Xiang pig supine on the operating table. The surgical site is at the abdominal midline 2-3 cm behind the umbilicus; centered on this, within an area of about 10 cm * 5 cm, first disinfect with 2% iodine tincture, then wipe with 75% alcohol. After covering the surgical site with a surgical drape, the operator fixes the skin at the surgical site with the index finger and thumb of the left hand. Hold the knife in the right hand, cut the skin once along the abdominal midline about 3-4 cm, and after fully stopping the bleeding, cut through the subcutaneous fat and rectus abdominis muscle, and incise the peritoneum. Then insert the index finger, extending along the abdominal wall to the dorsal side of the pelvic inlet to look for the ovary and uterine horn. The ovary is generally flat and oval, hard in texture and elastic. When the ovary is felt, clamp it between the index finger and the abdominal wall, pull it to the skin incision, then pinch it with the index finger and thumb and ligate with No. 4 thread. To prevent slipping, pass the needle and thread through the base of the ovary for double single-knot ligation, then cut off the ovary; if there is no bleeding, cut the tail thread and return it to the abdominal cavity. Use the same method to find the opposite ovary, or follow the uterine horn from which the ovary was removed to find the opposite ovary. After finding it, ligate and cut it in the same way. Then recheck once; if there is indeed no bleeding, close the abdominal cavity, suture the rectus abdominis muscle and peritoneum together in a continuous suture, sprinkle with 200,000 units of penicillin, suture the skin with interrupted sutures, and disinfect with 2% iodine tincture.

After surgery, do not let the Xiang pig go to ponds or let rain wet the wound, and feed some nutritious food. Most Xiang pig wounds need 1 week to heal, and the stitches should be removed in time. If infection is found, antibiotic treatment should be given promptly.

In addition, there is also the flank ovary removal method, which is suitable for surgery on larger Xiang pigs. The method is: after restraining the Xiang pig, disinfect immediately, hold the knife in the right hand, and at the determined site cut the skin with a 2-3 cm long crescent-shaped incision. Use the index finger of the left hand to puncture the abdominal muscles and peritoneum, insert into the abdominal cavity and extend along the abdominal wall to both sides of the top of the pelvic inlet; when the left ovary is felt, hook the ovarian mesentery with the index finger and hook it out along the abdominal wall. When the ovary is pulled to the incision, the ovary and uterine horn can also be hooked out together with the knife handle, and after ligating the ovarian mesentery with suture thread, the ovary can be removed. Then insert into the abdominal cavity again, pass below the rectum to the right side to feel the right ovary, and hook it out, ligate and remove the ovary in the same way. Then perform suturing, disinfection and other surgical treatment.