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Penopexy is the iatrogenic creation of phimosis by surgically creating an adhesion of the penis to the ventral body wall. This procedure prevents protrusion of the penis, thus preventing normal intromission or copulation. Penopexy is a relatively quick procedure and can typically be performed with sedation and local infiltration of 2% lidocaine. Tilt chute restraint or general anesthesia can also be utilized. Lateral recumbency is the preferred positioning.

The bull's ventral abdomen is clipped and surgically prepared from the preputial orifice to the scrotum. A skin incision is made 2–3 cm lateral of the midline and half the distance between the preputial orifice and scrotum approximately 10 cm in length. Carefully dissect the subcutaneous tissues until the penis is identified and exteriorized (Figure 21.7). Once the penis is exteriorized through the incision, identify the caudal reflection of the penis (fornix) and dissect the subcutaneous tissues on the dorsal aspect of the penis until the tunica albuginea is exposed for approximately 10 cm caudal to the fornix [4, 5]. Remove the subcutaneous tissue on the linea alba in conjunction with the dorsal aspect of the penis. The tunica albuginea and corresponding linea alba are scarified to promote strong adhesion formation. After preparation of both sites, the urethral groove is identified on the ventral aspect of the penis. Beginning 6–8 cm caudal to the fornix of the penis, pre‐place four to six simple interrupted sutures approximately 2 cm apart using a heavy non‐absorbable suture [4, 5]. The suture is placed through the dorsal third of the penis using care to not enter the urethra. The suture is then placed through a corresponding area of the linea alba (Figure 21.8) [4, 5]. Once all the sutures are pre‐placed, return the penis to the normal anatomical position and ensure it is not protruding from the preputial orifice prior to securing all the sutures (Figure 21.9). Close the subcutaneous tissue with absorbable sutures and the skin with #3 non‐absorbable suture in a Ford interlocking pattern. A vasectomy or epididymectomy is usually performed in conjunction with a penopexy to ensure sterility of the bull in case of procedure failure.

Figure 21.7 Exteriorization of the penis through the incision and identification of the caudal reflection of the penis.

Figure 21.8 Preplacement of sutures through the dorsal third of the penis and linea alba.

Source: Illustration by Mal Hoover.

Figure 21.9 Securing the stay sutures for penopexy.

Source: Illustration by Mal Hoover.

Allow three to four weeks of recovery to ensure proper formation of adhesions. The drawback of penopexy is the risk of entering the urethra and decreased longevity in the herd since the bull will experience pain during attempted erection, thus decreasing libido. A follow‐up study of 37 bulls found that 15% of bulls maintained good libido for one breeding, 30% for 1–1.5 years, and 42% for more than 1.5 years [5, 8].

A standing perineal penopexy approach has been described using light sedation and a caudal epidural. The approach is over the distal loop of the sigmoid flexure [4]. A 4‐ to 5‐cm incision is made through the skin and the tunica albuginea is exposed as mentioned previously. However, the stay sutures are placed on the lateral aspects of the penis and secured to the fibrous connective tissue in the perineal region of the bull [4, 5].