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As previously mentioned, vasectomy will render a bull sterile but does not prevent normal mating and copulation behavior. This procedure can be performed with the bull in standing restraint or recumbency, or a tilt chute may be used if available. The typical surgical approach is an anterior approach on the neck of the scrotum. However, if standing restraint is chosen, then the approach would be the posterior aspect of the neck of the scrotum. Figure 21.1 shows the procedure.

Figure 21.1 Procedure for vasectomy.

Source: Illustration by Mal Hoover.

The neck of the scrotum should be clipped and aseptically prepared for surgery. Lidocaine 2% should be infused over the proposed incision site over each spermatic cord. A 3‐cm incision should be made through the skin and tunica dartos over each spermatic cord. The spermatic cord is isolated by placing a hemostat underneath the entire spermatic cord. The ductus deferens is then identified via palpation. The ductus deferens is a firm structure that runs medially along the spermatic cord and is approximately 2–3 mm in diameter. 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 hemorrhage. After the tunica vaginalis is incised, the ductus deferens is isolated with another hemostat.

Two ligatures are placed approximately 3–5 mm apart using #0 absorbable suture [4, 5]. The ductus deferens is removed between the two ligatures. The skin is closed with a cruciate pattern using nonabsorbable suture. Antibiotics can be administered to prevent any postoperative infection, especially if surgical contamination has occurred. It is recommended to wait 30 days prior to using the bull as a teaser animal, since sperm can be present in the reproductive tract up to 30 days postoperatively [4, 5]. Additionally, it is recommended to perform yearly evaluations of the teaser animal's ejaculate to ensure sterility of the animal.