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The preputial pouch technique creates a fistula on the ventral prepuce and closes the normal preputial orifice. This technique prevents penile extension but allows for passage of urine through the ventral fistula. Teaser bulls with a preputial pouch are typically retained in the herd longer because libido is maintained for longer due to the lack of pain during attempted breeding [5]. This procedure is performed in lateral recumbency and can be accomplished with tilt chute restraint or sedation with local infiltration of 2% lidocaine. The ventral abdomen is clipped and prepared from the umbilicus to the midsheath region of the bull.

Prior to initiating surgery, the penis is extended and a Penrose drain is sutured around the glans penis with 2–0 polydioxanone (PDS). An approximately 1‐cm‐diameter elliptical incision is made through the skin 7 cm caudal to the preputial orifice (Figure 21.10). The skin incision is extended through the preputial mucosa. The excised skin and mucosa are discarded. Then the internal mucosa of the prepuce is sutured to the skin of the sheath to create the fistula. An interrupted non‐absorbable suture pattern is recommended (Figure 21.11a and b) [5]. Once suturing is complete, the free end of the Penrose drain is placed through the fistula. The Penrose drain will facilitate urine divergence while the primary incision sites heal.

Figure 21.10 Site for incision for ventral fistula.

Source: Illustration by Mal Hoover.

Figure 21.11 (a and b) Suturing of preputial mucosa to the sheath skin.

Source: Illustration by Mal Hoover.

The preputial orifice obliteration is accomplished by removing approximately 5 mm of the sheath skin and prepuce mucosal junction around the entire preputial orifice (Figure 21.12). This incision is closed in three layers: preputial epithelium, subcutaneous layer, and skin. The Penrose drain and sutures can be removed in two weeks. Allow three weeks of postoperative recovery time prior to utilizing the teaser bull [5].

Figure 21.12 Excision of 5 mm of the preputial epithelium and sheath skin junction.

Source: Illustration by Mal Hoover.

The critical step in the preputial pouch technique is the size of the fistula. If the fistula is too small, proper urine flow is obstructed. If the fistula is too large, penile extension can occur with potential breeding. Therefore it is recommended to perform a vasectomy or epididymectomy to ensure sterility of the bull. Some bulls may pool urine in their preputial pouch and require postoperative flushing of the pouch. Thus this technique is not recommended for Bos indicus breeds since their pendulous sheath would predispose them to urine pooling and calculi formation [5].