Castrating Alpacas

Practicing veterinarians are sometimes asked to castrate pet quality males at 4 to 6 months of age, so that the pets may be quickly sold. However, many veterinarians feel that it's best to wait until the male is 18 to 24 months of age to ensure that his musculoskeletal system has reached its mature state.

Many veterinarians are concerned that alpaca and llama males castrated before puberty have delayed closure of long-bone physes. This results in geldings with a tall, straight legged stature (particularly of the hind limbs). In llamas, lateral patellar luxation and early onset of degenerative osteoarthritis of the stifle joints have been seen as complications of this posture. Historical data usually reveals that the affected males were castrated at an early age (e.g. 4 months).

Castrating Techniques

Basically, any animal castration method that has been used in other livestock and pet animals has been done successfully in camelids. However, two methods have become standards of practice: scrotal castration (similar to horses and swine) and pre-scrotal castration (similar to canine). Veterinarians routinely administer tetanus toxoid vaccination and procaine penicillin G (22,000 U/kg, q24h x 3 d) to the animal being castrated. Food should be withheld for 12 hours prior to castration in case general anesthesia or heavy sedation becomes necessary.

Scrotal castration can be done with the animal standing or lying down. For standing castration, the camelid is sedated, and an epidural is administered. The scrotum is prepared for aseptic surgery and, if an epidural was not used, 2 ml lidocaine is injected as a line block along the median raphe. A 2 cm incision is made on either side and parallel to the median raphe along the ventral most aspect of the scrotum. Each testicle is then removed and excised.

Pre-scrotal castration is done with the animal lying down. Strict aseptic technique is critical to ensure that infection of the castration site does not develop. A 2 cm incision is made on ventral midline immediately cranial to the ventral base of the scrotum. Then each testicle is removed through this incision and excised after transfixation ligation. After hemostasis has been achieved, the skin incision is closed using a subcuticular or subcutaneous suture pattern.

Post-Operative Care

The castrated male should be placed in a small pen for 24 to 48 hours after scrotal castration. Confinement is not needed after pre-scrotal castration. Owners should monitor the incision for bleeding, swelling, discharge, fly infestation, difficulty urinating, and any other problems. Although complications are uncommon, the consequences of postoperative problems can be devastating.