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that serve an artificial vagina (AV) for semen collection for artificial insemination. This injury rarely occurs during natural breeding. The prepuce adheres to the latex liner of the AV and the prepuce is torn loose from the penis when the bull makes the ejaculatory lunge. Contrary to other types of lacerations, those that occur in an AV should be sutured immediately. The wounds are quickly diagnosed and comparatively clean and excellent healing is expected with immediate primary closure of the wound. If the injury is not immediately closed by suture, surgical repair should be delayed until the wound is completely covered by healthy granulation tissue. With local anesthesia of the penis, prepare the surgical field for aseptic surgery, undermine the retracted prepuce, and slide it distally to the normal position and appose the prepuce to the free portion of the penis with absorbable suture.
Ring Amputation
Often a client will choose to cull rather than allow treatment. Because these bulls are the victims of severe price discrimination, I will offer a salvage‐type procedure. A large swine rectal (prolapse) ring or short length of PVC pipe is placed within the preputial lumen dorsal to the lesion and a band is placed around the prepuce over the pipe. This will amputate the damaged prepuce, but fibrosis and stenosis will likely occur. Alternatively, holes can be drilled in the PVC pipe prior to placement and, rather than a band, heavy (6‐mm) Braunamid™ is utilized in an overlapping pattern. The overlapping suture serves to both fix the tube and provide for hemostasis when the end of the prepuce is amputated [3]. This is the “ring amputation” procedure and can be performed with the bull standing, utilizing local analgesia and chute restraint [1]. This procedure usually results in some degree of stricture. It should be noted that correction with the circumcision technique remains an option for bulls in which the ring amputation results in a stricture and thus it might be considered for the client that desires a more economical option than lengthy medical treatment prior to surgical correction by circumcision (Figures 19.27 and 19.28).
Figure 19.27 PVC pipe prepared for use in “ring technique.”
Figure 19.28 Ring sutured in place, inside prepuce.
Circumcision (Reefing)
The surgical technique for repair that is advocated by the authors is the circumcision or “reefing” technique. The bull must be tabled and is often anesthetized, but this procedure can be performed with regional analgesia and heavy sedation. Prior to surgery, the bull is fasted for 36–48 hours and water withheld overnight. The bull is placed in right lateral recumbency and the hair of the sheath is clipped. The penis is extended and maintained in extension with towel forceps that engage the apical ligament. The penis and prepuce are prepped (NO alcohol) and draped. A tourniquet is applied utilizing 1‐inch Penrose tubing, proximal to the area to be transected. The amount of prepuce to be resected is then determined (the remaining prepuce must be a minimum length of 1.5× the free portion). Two marker sutures are placed on what will be the adjoining edges of the suture line to ensure that tissues are returned in the proper alignment. Two circumferential incisions are made with these representing the edges of the epithelial tissue to be removed. These incisions are then joined with a longitudinal incision. The incisions are to be very superficial so that with careful, sharp dissection, underlying tissue, blood vessels, and lymphatics will be spared. The area of fibrosis should be included in the tissue removed. Following dissection and tourniquet removal (the tourniquet can be maintained safely for up to 1 hour); hemorrhage is controlled by vessel ligation and/or cautery. When hemostasis is achieved, lavage the area with a warm solution of sterile saline with 50 ml Betadine Prep Solution added per liter of saline. The edges are sutured with a simple continuous subcuticular pattern using your choice of 2–0 absorbable suture material.
Do not use a single continuous pattern, but instead end the pattern and restart in three stages to avoid a constrictive (purse‐string) effect. Do not close dead space. This can then be followed with a row of staples or closed with your choice of suture pattern with 0 chromic gut. Then suture in place Penrose tubing over the end of the penis. An antibiotic ointment is applied to the wound and, placing the free end of the Penrose tubing into a 6‐ to 10‐inch rigid tube, the penis and prepuce are carefully returned into the sheath and bandaged. The bandage can stay on as long as a week; the staples can be removed in two weeks. A support wrap (Bull diaper) or sling as previously described can be employed to protect the bandage and prevent pendulant swelling (Figures 19.29–19.39).
Figure 19.29 Penis extended in preparation for circumcision. Note loose excessive prepuce.
Figure 19.30 Determination of length of free portion of penis.
Figure 19.31 Proximal end of free portion indicated by surgeon’s left forefinger.
Figure 19.32 Length of excess prepuce measured from end of sheath (surgeon's small finger) to preputial ring (surgeon's thumb).
Figure 19.33 (a) Circumferential and longitudinal skin incisions in preputial epithelium. Note Proximally placed Penrose drain which serves as tourniquet. (b) Schematic of circumferential and longitudinal skin incisions for circumcision of a bull.
Figure 19.34 Dissection and removal of preputial skin and scar tissue.
Figure 19.35 Subcutaneous closure with continuous pattern. Note this closure performed in thirds.
Figure 19.36 Preputial epithelium suture closure.