Detailed Explanation and Operation Methods of Pig Castration Techniques

Pig castration is one of the castration techniques for various livestock, poultry and pets. It occupies an important position in veterinary surgery and is an indispensable technique in @#@227@#@ production. Here a brief explanation of pig castration techniques is provided.

The principle and purpose of pig castration: the ancients called the testis "shi", so removing the testis of male livestock is also called desexing, and this term has been used to this day. Of course, the castration of livestock and poultry includes not only male livestock and poultry but also female livestock and poultry. Castration of livestock and poultry is the removal of the reproductive glands of livestock and poultry, that is, the removal of the testis or ovary. The same applies to castrating pigs. After castration, boars and sows lose their sexual physiological function, their temperament becomes docile, which facilitates feeding and management, allows mixed-group raising, and reduces labor and costs; it can make the meat more tender and without a gamy smell, can promote growth, facilitate fattening, shorten the feeding cycle, and improve economic benefits; it can eliminate inferior breeds and facilitate selective breeding of good breeds, and so on.

(1) The content and subjects of pig castration techniques

There are boar castration techniques, sow castration techniques and hermaphroditic pig castration techniques. Boar castration techniques include those for small boars, large boars, cryptorchid pigs and scrotal hernia pigs. Sow castration techniques include those for small sows, large sows and "chagao" pigs. The castration of various subject pigs has different technical requirements. The castration technique for small boars is suitable for piglets before weaning! weeks or within ! weeks after weaning, with a body weight of 15 kg. Large boars that have lost breeding value can be castrated in all four seasons.

The castration technique for small sows is also called the small piercing-flower technique, generally referring to small sows aged 28 to 80 days and weighing 5 to 15 kg. There are also those castrated within " months after birth, at body weight. We generally carry it out at around (7 days, simultaneously with the small boars in the same pen.

The castration technique for large sows is also called the large piercing-flower technique, and is also called the feeling-flower technique. It is suitable for larger individuals or culled multiparous sows that have already been in heat. Its characteristic is that after the surgical incision is made, the fingers are inserted directly into the abdominal cavity to take out the ovary and remove it. The "chagao" pig castration technique is also called the running-flower pig castration technique. Because the previous castration was not thorough and the uterine horn was torn off while the ovary still remained in the abdominal cavity, a repeat operation is needed to remove the remaining ovary.

Hermaphroditic pig castration technique: hermaphroditic pigs are mostly related to inbreeding, are hermaphroditic, outwardly resemble sows, and often mount other pigs in the herd. There are two types: in the first type, one side inside the body is an ovary and the other side has a testis, and the castration method should use the large piercing-flower operation for sows to remove it; in the second type, there are testes on both sides inside the body, and the castration method uses the method of removing cryptorchid testes for removal.

(2) How to carry out pig castration techniques well

1) One must understand the anatomical knowledge of castration surgery

Whether castrating boars or sows, the operator must be familiar with the structure, position, characteristics and related physiological functions of the tissues and organs related to the surgical site, so as to correctly, safely and quickly perform the operation. The reproductive organs of the boar consist of the scrotum, tunica vaginalis communis, testis, epididymis, spermatic cord and mesorchium, accessory sex glands and penis, etc. The scrotum is located behind the two hind limbs of the boar. Below the anus, it is divided into two halves internally by the scrotal septum, and there is a scrotal raphe in the middle, which is the positioning marker for the surgical incision in boar castration. The testis and epididymis are connected together, and within the scrotum there is one testis on each side; the testis is the place where sperm are produced and hormones are secreted, and the epididymis is the place where sperm mature and are stored. The testis and epididymis are the organs that must be removed during castration. The reproductive organs of the sow consist of the ovary, oviduct, uterus, vagina and urogenital vestibule, etc. The uterus, oviduct and ovary are all located within the pelvic cavity. The ovary is on both sides at the entrance of the pelvic cavity, one on each side, and its external position is slightly behind the hip tubercle, so the hip tubercle becomes the main landmark for determining the incision site for the large piercing-flower operation in large sows. The ovary is the organ that produces ova and secretes hormones, and is the organ that must be removed in sow castration surgery. The anatomical layers of the soft abdominal wall at the surgical site for sow castration, from the surface inward, can be divided into skin, subcutaneous connective tissue, external oblique abdominal muscle, internal oblique abdominal muscle, rectus abdominis muscle, transverse abdominal muscle, extraperitoneal muscle, peritoneum and other tissues, which the operator must also understand.

2) Equipment and medicines must be prepared well. Surgical knives, castration knives, hemostatic forceps, needle holders, surgical scissors, surgical tweezers, fully curved suture needles, sutures, etc. must be prepared. Disinfectant solution (benzalkonium bromide, chlorhexidine), alcohol, alcohol cotton balls, sulfonamide crystal powder, penicillin and anti-tetanus serum, etc. must be prepared.

3) Preoperative examination and preparation must be done well

First, the condition of the pig herd should be inquired about and observed. For those with poor spirits, indigestion, diarrhea, or a thin and weak constitution, the operation may be temporarily postponed and castration performed after recovery. Only healthy pigs without disease may be castrated. Before the operation, the owner should be asked to withhold one meal. The castration time is best arranged in the morning or before evening, because the weather is cool at these times, avoiding high temperatures, which is beneficial to the operation and postoperative recovery. Before the operation, separate the old sows from the piglets to prevent the old sows from injuring people during the castration process. Piglets should be penned in a narrow pen for easy capture. The pen where castrated piglets are placed should have pits filled level, accumulated water and urine drained, be cleaned thoroughly and spread with clean bedding straw, and kept dry. The surgical site should be chosen in a slightly sloped, clean, dry and wind-sheltered place. Castration is not suitable in strong wind or rainy days.

4) Surgical restraint must be done well

Restraint is crucial to whether the operation proceeds smoothly. For the operation on small boars and small sows, the operator alone can restrain the animal. For operations on large boars and large sows, an assistant is needed to cooperate. Boars generally use the method of lying laterally on the left side, and sows use the method of lying laterally on the right side.

5) The incision must be correctly positioned

Positioning the incision for boars is relatively convenient. The operator firmly grips the scrotum and testis, and at the place where the testis is most prominent and the scrotal skin is stretched tight, makes an incision parallel to the scrotal raphe, cutting through the skin and tunica vaginalis communis in one pass, and squeezes out the testis. For determining the incision site of the small piercing-flower operation on small sows, take the left hip tubercle (hip point) as the point, and draw an imaginary vertical line toward the abdominal midline (white line). The operator presses the pad of the left middle finger against the hip tubercle, presses the same-side abdominal wall with the thumb, and with the thumb and middle finger on the imaginary vertical line, at a place about two finger-widths from the same-side teat, is the incision site. One may also refer to the rear one-third position between the third-to-last teats, incising to the side.