incision with #3 absorbable suture, closing as much dead space as possible to prevent seroma formation. Close the skin with #3 non‐absorbable suture in a Ford interlocking pattern. Place a cruciate suture at the cranial aspect of the incision to be removed for drainage if a seroma does occur.
Figure 21.6 Closure of new preputial orifice with interrupted sutures and ventral midline with Ford interlocking pattern.
Source: Photo courtesy of Tom Thompson.
The teaser bull should be monitored closely for 24 hours postoperatively to ensure he is able to urinate properly. Antibiotics should be administered for three to five days postoperatively to prevent infection. Allow four to six weeks of recovery time before using the teaser bull [3–5]. Penile–prepuce translocation is not a technically difficult procedure, but it is more invasive and can result in more postoperative complications. The most common complications are obviously seroma and abscess formation from the excessive dead space created. Another complication would be not translocating the preputial orifice high enough on the flank and thus the bull would still be capable of breeding a female animal. There is also one case report of a teaser bull developing paraphimosis with a penile–prepuce translocation [7].
Penopexy
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].
Preputial Pouch Technique (Ventral Slot with Preputial Orifice Obliteration)
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.
