Vasectomy in Bulls: Indications, Surgical Procedure, and Post Operative Care

Vasectomy in bulls is a surgical procedure in which a portion of the vas deferens (the duct that carries sperm from the testicles) is removed or blocked to render the bull sterile. This procedure prevents the bull from ejaculating sperm while allowing it to retain normal libido and mating behavior.

It is most commonly performed to produce teaser bulls — sterile bulls used to detect cows in estrus (heat) without the risk of fertilization.

Indication

• To identify the cow in estrus (teaser bull) and to prevent the ejaculation.
• Vasectomy will render a bull sterile but does not prevent normal mating and copulation behaviour.

Surgical Procedure

1. Vasectomy in bulls procedure can be performed with the bull in standing restraint or recumbency.
2. Although an epidural anaesthesia may be sufficient, vasectomies are usually performed with the aid of a local block at the surgical site.
3. Vasectomy is performed at the neck of the scrotum (Posterior surface or anterior surface or median raphe).
4. The neck of the scrotum should be clipped and aseptically prepared for surgery.
5. Lignocaine (2%) should be injected over the incision site over each spermatic cord.
6. A vertical single incision can be made on the median raphe of the scrotum, approximately 2 to 4 cm in length and carried through the skin and the common layer of the vaginal tunic.
7. The parietal layer of the vaginal tunic is carefully incised to expose the contents of the spermatic cord.
8. Care must be taken with this step to prevent accidental incision of the underlying pampiniform plexus, which may result in serious haemorrhage.
9. Once the contents of the spermatic cord have been exposed the vas deferens must be identified.
10. The vas deferens is a firm structure that runs medially along the spermatic cord and is approximately 2-3 mm in diameter.
11. Once identified, the tunica vaginalis is carefully incised, utilizing extreme caution so as not to damage the cremaster muscle or pampiniform plexus resulting in excessive haemorrhage. After the tunica vaginalis is incised, the vas deferens is isolated.
12. Two ligatures are placed approximately 2-3 cm apart using size 0 absorbable sutures. The vas deferens is removed between the two ligatures. The vaginal tunics are usually not sutured and the skin is closed with non-absorbable sutures.
13. Histopathology should be done to confirm the vas deferens.

Post Operative Care

• Daily or alternate dressing with antibiotic ointment.
• Parental antibiotics 5 to 7 days, analgesic for 2 to 3 days.
• Restricted movement of animal.
• Removal of skin suture on 8th to 10th postoperative day.
• Sperm can remain viable in the tract for up to 30 days; therefore it is advisable to not use this bull as a teaser bull for at least 30 days.
• Perform yearly evaluations of the teaser animal’s ejaculate to ensure sterility of the animal.