Bovine Reproduction. Группа авторов
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midline from the preputial orifice to just cranial to the scrotum (Figure 21.4). Carefully dissect the penis and prepuce from the ventral abdomen. Avoid lacerating the prepuce; packing or tubing can be placed in the prepuce to aid with proper identification. While dissecting the penis and prepuce, avoid incising the dorsal penile vessels and control hemorrhage as it is encountered. Once the penis and prepuce are dissected, make a circular skin incision equivalent to the diameter of the preputial orifice at the desired translocation site (Figure 21.4). Use a sponge forceps to create a tunnel toward the flank incision. As the forceps is retracted, open it slightly to help facilitate penile translocation. This tunnel can also be accomplished with a cold sterilized polyvinyl chloride (PVC) pipe (Figure 21.5).
Figure 21.3 Circumferential incision 4 cm from the preputial orifice is performed with an interrupted suture placed at the dorsal aspect of the preputial orifice to prevent twisting during translocation.
Source: Photo courtesy of Tom Thompson.
Figure 21.4 Ventral midline incision extending caudally with circumferential incision at the translocation site.
Source: Photo courtesy of Tom Thompson.
Figure 21.5 Use of a cold sterilized PVC pipe to facilitate tunneling of penile translocation and skin incision for the translocation site.
Source: Photo courtesy of Tom Thompson.
Place a sterile glove or sleeve over the preputial orifice to minimize contamination of the subcutaneous tissues. Then run a sponge forceps from the flank incision to the ventral midline incision and grasp the preputial orifice. Manipulate the preputial orifice to the flank incision, taking care not to twist the prepuce (use a stay suture to ensure proper alignment). Suture the skin around the preputial orifice using #3 non‐absorbable sutures with a cruciate or horizontal mattress pattern (Figure 21.6) [1]. Close the subcutaneous layer of the ventral midline 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.