Bovine Reproduction. Группа авторов

may allow sufficient penile protrusion for semen collection. In my experience (Wolfe), two bulls were able to successfully complete coitus following this surgical procedure. With the bull adequately restrained and following preparation for aseptic surgery, make an elliptical incision through the skin. This incision is made on the ventral sheath sufficiently proximal to the scar tissue to penetrate the lumen of the preputial cavity (Figure 19.46). The diameter of the stoma should be sufficiently large to allow the free portion of the penis to extend, but not sufficiently large that the remaining prepuce may prolapse. Following removal of the elliptical skin, continue dissection through the peri‐penile elastic layers and elevate the prepuce through the opening in the sheath (Figure 19.47). Incise the prepuce (Figure 19.48) and exteriorize the free portion of the penis through the incision (Figure 19.49). Using #0 absorbable suture, appose the skin of the prepuce to the skin of the sheath with a simple interrupted pattern (Figure 19.50). Suture a 2.5‐cm Penrose drain over the free portion of the penis to allow postoperative urine drainage away from the incision (Figures 19.51–19.53). Remove the Penrose drain 10 days postoperatively and allow 60 days’ sexual rest prior to attempted semen collection (Figure 19.54).

Figure 19.46 Triangular flap of skin removed from sheath (apex of triangle oriented toward scrotum).

Figure 19.47 Prepuce elevated through incision in sheath.

Figure 19.48 Incision into preputial cavity to create stoma.

Figure 19.49 Free portion of penis exteriorized through preputial stoma.

Figure 19.50 Preputial epithelium apposed to skin of sheath with interrupted absorbable sutures.

Figure 19.51 Penrose drain sutured over free portion of penis.

      Figure 19.52 Penrose drain over penis through preputial stoma for urine drainage.

Figure 19.53 Postoperative image of bull with preputial stoma. (Note Penrose drain is through natural sheath opening.)

Figure 19.54 Completely healed preputial stoma ready for attempted semen collection.

Paraphimosis

      Paraphimosis with resultant injury from penile exposure can be managed with a combination of medical and surgical therapy. Because of the inability to completely retract the penis, significant damage to the epithelial layers of the penis occurs (Figure 19.14).

      Soaking the affected areas, as described previously for preputial prolapse, should occur immediately and be continued daily until there is a return to the normal appearance of the tissue. In between the therapeutic soaking the penis is covered with stockinette that has been coated in a suitable ointment (the authors’ preference is one of the commercially available “bag balms”). Realize that three to four weeks of medical management is often required before the tissue is healed and surgery can be performed. Once the superficial layers are healed, a scar revision procedure as previously described to allow the penis normal retraction/extension can be performed.

Hematoma

Hematoma of the penis is probably the most common injury of the penis. This injury occurs when the penis misses the intended target, hits the cow's perineum, and bends. Although it usually occurs in young inexperienced bulls [411–13] it can also occur in the older bull, which due to orthopedic injury or pain has altered his approach during mounting. From a seasonal standpoint, it usually occurs early in the breeding season when the bull is an aggressive breeder and a large number of females may be cycling, or conversely late in the breeding season when the bull may be fatigued and perhaps has lost body condition and is not as athletic or becomes awkward or clumsy during his breeding attempts. The hematoma results due to rupture of the tunica albuginea and subsequent hemorrhage from the corpus cavernosum. The initial volume of blood escaping is less than 250 ml [4], but the size of the resultant hematoma varies as each subsequent erection results in further hemorrhage. Thus the hematoma may range in size from 15 to 30 cm. The resultant swelling occurs in the sheath over and cranial to the rudimentary teat (Figure 19.55). A prolapsed prepuce often results and this in fact may be the owner's reason for seeking help. Diagnosis may be aided with ultrasound, but, typically, a diagnosis is made from history and physical diagnosis. Do not attempt to aspirate the swelling, as inadvertent introduction of bacteria can convert a hematoma to an abscess.

Figure 19.55 Hematoma location.

      Approximately 50% of bulls with rupture of the tunica albuginea return to breeding soundness without surgical repair of the injured penis. Conservative therapy consisting of absolute sexual rest for a minimum of 60 days (and avoiding extension of the penis) with systemic antibiotic therapy for the first 7–10 days is recommended. Daily hydrotherapy of the swollen sheath