Surgical Castration

The most common surgical procedure performed on goats is castration. Complications include excessive hemorrhage, evisceration, infection, rupture or tearing of the ureter, and tetanus.¹ Tetanus prophylaxis should include the use of toxoids and antitoxins. Evisceration appears more common in young goats, and possibly has some breed predisposition (pygmy¹). Routine castration of kids is usually done the first week of life. However, if the kid is to be a pet, it is advisable to wait until at least 5 to 6 months of age in order to allow for maturation of the penis, urethra, and detachment of penile adhesions.¹

Animals may be sedated, anesthetized, or restrained by an assistant. Young lambs or kids 2 to 4 days old are often surgically castrated without anesthesia. Light sedation of pet goats can be beneficial owing to their propensity for vocalization. Local anesthesia can be achieved by local infiltration of a 1% lidocaine hydrochloride solution in the scrotum and around the spermatic cord. Large, adult bucks should be sedated (xylazine hydrochloride, 0.05–0.3 mg/kg IM) as they may be very susceptible to shock associated with the stress and pain of castration.¹ The lower one third of the scrotum is removed by a scalpel blade to expose both testicles. The scrotal fascia is stripped away and testicle is identified and pulled by steady traction ventrally while the cremaster muscle and the remaining scrotal fascia are torn away from the spermatic cord. Completely tearing away the cremaster muscle and the scrotal fascia will allow more of the spermatic cord to be exposed to ensure it is broken above the pampiniform plexus. The cord is broken by applying constant downward pressure on the testicle with one hand to expose as much of the spermatic cord as possible and then breaking the cord as dorsally as possible by applying pressure on the cord with the other hand.¹ Breaking the cord above the pampiniform plexus will generally result in less hemorrhage than breaking the cord at or below the plexus.

In bucks older than 4 months of age and during the breeding season, it may be necessary to place an emasculator or transfixation ligature dorsal to the pampiniform plexus, in order to control hemorrhage. If hemorrhage appears to be clinically significant, the bleeding vessels should be ligated. If bleeding vessels cannot be identified, the scrotum can be packed with sterile gauze (soaked in antiseptic iodine or epinephrine) and the scrotum sutured closed. An alternative would be to close the scrotum with purse-string or a through-and-through suture pattern in order to reduce dead space within the scrotum. The day after surgery the scrotum should be reopened and the gauze removed. If the scrotum is packed, the animal should be placed on antibiotics for 1 to 4 days. On rare occasions when the testicles are pulled, the testicular artery may be avulsed from the aorta, which can result in fatal hemorrhage.² Animals need exercise after castration in order to reduce postoperative swelling.¹

Elastrator Band Technique

The use of the elastrator band is the most commonly used technique by many producers on animals under 3 to 4 weeks of age. A heavy rubber band is placed around the neck of the scrotum. The entire scrotum is included within the bands.¹ Pulling the testicles as far ventrally as possible away from the abdominal wall before placing the bands will prevent trapping penile structures (sigmoid flexure) within the band. Elastrator band methods are considered inhumane by some if performed on animals over 1 to 3 weeks of age.² The scrotal sac and the trapped testicles undergo ischemic necrosis and slough within 2 weeks. It has an advantage of no open wounds or hemorrhage, but is associated with an increased risk of tetanus.² Occasionally the blood supply to one or both testicles will not be occluded, and the testicles will remain and continue to function.²

Burdizzo Emasculatome

Another method for castrating sheep and goats involves using the emasculatome. There are no open wounds and compared to elastrator bands there is a decreased risk of tetanus. Anesthesia is not required. The testicle is pushed to the ventralmost part of the scrotum and each cord is held tightly against the lateral aspect of the scrotum with one hand while the Burdizzo emasculatome instrument is applied twice to each cord.¹ Clamping each cord separately increases the likelihood of interrupting the testicular blood supply and decreases the incidence of scrotal sloughing. The complications of this method include testicular survival, scrotal sloughing, scrotal swelling, and tetanus. Some consider this an inhumane method of castration in older animals.¹

Hemicastration

In cases of unilateral testicular disease, the decision may be made to remove the involved testicle in order to prevent heat-induced testicular degeneration of a normal testicle that may occur as a result of inflammation in the diseased testicle. General anesthesia is recommended. The male is anesthetized, placed in right lateral recumbency, and the entire scrotum and the surrounding area are clipped and aseptically prepared. Starting near the base of the affected testicle and extending to near the apex, an elliptical incision is made through the skin and tunica dartos on the lateral aspect on the scrotum. The incision should not be extended into the normal hemiscrotum. The affected testicle and its associated tunics are bluntly dissected away from the scrotum. The vaginal tunics are excised in order to expose the testicle and the spermatic cord. The spermatic artery and vein are ligated with a transfixation suture above the pampiniform plexus, and the cremaster muscle is ligated at a point proximal to the vascular ligature. A separate ligature is then placed around the entire spermatic cord. The cord is clamped approximately 5 to 6 cm distal to the vasculature suture, and the cord transected. The remaining vaginal tunic is transected far enough distally to allow the tunics to be closed over the remaining cord with an inverting suture pattern. Excess skin should be trimmed so that no dead space is present. The tunica dartos muscle and the longitudinal skin incision are closed separately. If excess hemorrhage is expected, the scrotum may be bandaged following surgery. The bandage should be removed within 12 hours after surgery to minimize thermal damage to the remaining testicle. Routine postoperative antibiotics (penicillin or tetracycline) should be continued for 4–5 days. Nonsteroidal anti-inflammatory drugs may be indicated for control of pain, swelling, and other signs of inflammation.¹

Teaser Preparation

Teaser bucks greatly facilitate estrus detection for artificial insemination and embryo transfer programs, particularly if used in conjunction with marking harnesses. A young, healthy, postpubertal male with good libido would be the best choice. The male should be incapable of intromission in order to minimize the spread of venereal disease or contamination of the vagina prior to artificial insemination. He should also be rendered infertile in order to guarantee no offspring are produced.

Vasectomy

A properly performed vasectomy will render the male incapable of fertilization, but will not prevent intromission. The animal is mildly sedated (xylazine 0.05 mg/kg IM) and the area proximal to the scrotum is infiltrated with lidocaine and prepared for aseptic surgery. The spermatic cord is identified and the overlying skin is incised. A combination of blunt and sharp dissection is used to carefully isolate the vas deferens from surrounding structures of the spermatic cord. Two ligatures are placed 4 cm apart on the vas deferens and a 2-cm section of the vas deferens is removed. The skin is closed with sutures, staples, or by a subcuticular pattern.³ The procedure is repeated on the remaining vas deferens. Alternatively, the procedure can be performed through a single incision over the spermatic cord. The buck should not be used for estrus detection for 30 days.¹

Epididymectomy

Like the vasectomy, an epididymectomy will not prevent intromission but will prevent emission of sperm. Bilateral caudal epididymectomy is a simple surgical procedure and easier to perform than a vasectomy.⁴ The distal scrotum is aseptically prepared. A local anesthetic is infiltrated in the skin over the tail of the epididymis. The testis is forced distally in the scrotum until the tail of the epididymis is easily identified through the scrotal skin. A skin incision is made over the epididymal tail and continued through the common vaginal tunic until the tail of the epididymis is exposed. The tail of the epididymis is grasped with a pair of towel forceps, and dissected away from the testicle. The epididymis should be isolated and sutures placed proximal and distal to the tail of the epididymis. A portion of the epididymis is removed. In an alternative method, a pair of forceps are clamped across a loop of epididymis and this portion of the epididymis removed. The authors suggest the loop of epididymis be stored in a container with formalin labeled with the owner’s name and the goat’s identification. This can later be used as evidence that the surgery was performed correctly. If the epididymis is sutured and the procedure is performed under aseptic conditions, the scrotal skin may be sutured. In less than sterile conditions, the skin is left open to granulate. A minimum of 30 days of sexual rest should be enforced before use in a teasing program.^1,3