Bovine Reproduction. Группа авторов
Читать онлайн книгу.Figure 19.37 Preputial epithelium closed with staples.
Figure 19.38 Penrose drain sutured over free portion of penis for urine drainage.
Figure 19.39 Prepuce bandaged with Penrose drain within rigid tube.
Amputation of the Prepuce
Amputation of the prepuce is occasionally performed on young bulls of B. indicus breed to prophylactically shorten an excessively long prepuce to reduce the likelihood of preputial laceration when the bulls begin breeding. The advantage of this procedure is that it is quick to perform compared with circumcision. The disadvantage is that there is more elastic tissue removed, as well as underlying vasculature and lymphatics, and likely edge‐to‐edge apposition of skin, creating a higher incidence of preputial stenosis compared with circumcision. The surgeon should also keep in mind that the prepuce is a tubular structure and that with wound contracture stenosis is more likely.
With the bull adequately restrained for aseptic surgery, infiltrate local anesthetic in the skin of the sheath just proximal to the preputial orifice. Incise the prolapsed prepuce into the preputial lumen approximately one‐third of its circumference and ligate bleeders. Suture the internal and external layers of skin with #0 absorbable suture using a simple continuous pattern. Repeat the procedure for the remaining two‐thirds of the circumference of the preputial prolapse. Suture a Penrose drain over the glans penis as previously described and revert the prepuce into the preputial cavity. Place an elastic bandage over the sheath as previously described and manage postoperatively as for circumcision.
Preputial Reconstruction by Scar Revision
Following healing of a preputial laceration and when the length of the healthy prepuce is insufficient to allow circumcision, the bull may be returned to breeding soundness with scar revision and preputial reconstruction. Restrain the bull and prepare the prepuce for aseptic surgery. With the penis extended, excise only the superficial transverse scar tissue (Figures 19.40–19.43). Return the edges of the preputial laceration to their original longitudinal orientation. Loosely place an absorbable bootlace suture in a longitudinal plane such that the free ends are toward the sheath (Figure 19.44). Place a 2.5‐cm Penrose drain over the free potion of the penis and revert the penis into the preputial cavity (Figure 19.38). Tighten the sutures to appose the skin edges as you allow the penis to return to within the prepuce (Figure 19.45). You will restrict retraction of the penis if you tighten and tie sutures prior to this.
Figure 19.40 Preputial scar. This scar did not restrict extension of penis, but was painful enough to deter breeding.
Figure 19.41a Scar dissected in transverse plane.
Figure 19.41b Tissue stretched and incised area takes on oval appearance. Closure will be done in longitudinal plane with bootlace suture pattern.
Figure 19.42 Extensive fibrosis. Penis is observed following manual extension.
Figure 19.43 Scar dissected.
Figure 19.44 Closure with bootlace pattern in longitudinal orientation.
Figure 19.45 Schematic of closing incision with bootlace suture pattern when penis returned to retracted position.
The purpose of this procedure is to allow the surgical wound to heal in a longitudinal plane and to maintain normal elastic tissue function. Since no elastic tissue or preputial skin is removed with this procedure, first intention healing should reduce the risk of preputial stenosis and allow subsequent penile extension. Most bulls require 60–120 days for the penis to freely extend following this procedure. Do not forcefully extend the penis during the convalescent period as the potential trauma increases the likelihood of excessive scar formation. Most bulls begin to masturbate within a few weeks following surgery and will stretch contracted tissues without permanent damage.
Phimosis
Preputial injuries that occur on B. taurus breeds typically result in phimosis rather than prolapse and therefore represent a different sort of challenge. If the penis is forcefully extended and then not repaired and replaced within the sheath at the same time, paraphimosis may result. The prepuce can be lavaged with an antiseptic solution. Then apply an ointment of your choice and allow second intention healing to occur. If there is extensive swelling, infection, and inflammation (phelgmon), it is usually best to allow the bull one to three months to heal as much as possible on its own before attempting surgical correction. Continued treatment attempts in the face of extensive inflammation as described is virtually always unrewarding. Ascertain the extent of fibrosis and whether or not the penis can be extended (some bulls that can extend will still require surgery). In addition, it is common to encounter one or more abscesses. Scar tissue often must be removed to allow easy, painless, and full extension of the penis. Unlike B. indicus influenced bulls, these bulls rarely have enough preputial tissue to allow for a circumcision. A scar revision technique as previously described can usually be utilized.
Creation of Preputial Stoma
Occasionally bulls with preputial injury or frostbite develop extensive scar tissue such that there is insufficient length of healthy prepuce for scar revision and preputial reconstruction or circumcision. Creation of a stoma from the preputial cavity