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Bovine Reproduction


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in a manner identical to that described for B. indicus bulls, but the outcome is often altered by phenotype. B. taurus breeds are more likely to retract all the damaged tissues into the preputial cavity following injury and as a result the wound is less likely to be noticed early. The visible preputial swelling may be confined to a well‐defined area adjacent to the bull's sheath, or may be more diffuse and occasionally extend from the preputial orifice caudally toward the scrotum. Because the compromised elastic tissues within the preputial cavity are contaminated with bacteria, cellulitis and phlegmon develop rapidly, often progressing to abscess formation.

      Therapy for retropreputial cellulitis, phlegmon, and abscessation relies on systemic antibiotic administration and local wound management. Daily flushing of the preputial tissues with dilute antiseptic solutions and cold water hosing of the sheath aid in resolution of cellulitis. Drainage of a retropreputial abscess into the preputial lumen at the site of the original injury may facilitate recovery but is difficult to accomplish. No attempt should be made to drain a retropreputial abscess through the overlying skin of the sheath as inflammation and sepsis of the underlying elastic tissues are inevitable and subsequent formation of peripenile adhesions will decrease the chance of a successful outcome [17, 18]. Even with aggressive therapy the prognosis is guarded to poor and many affected bulls never return to service [17].

      Phimosis

      Phimosis, the inability to extend the penis, effectively prevents the bull from breeding and may be diagnosed at the time of an observed breeding or by induction of erection with an electroejaculator. Phimosis may be due to stenosis of the preputial opening or lumen, adhesions within the elastic layers of the prepuce and surrounding skin, or occasionally abnormalities of the distal penis including the presence of large penile fibropapillomas.

Photo depicts phimosis due to circumferential stricture of the preputial cavity following preputial laceration.

      Source: Courtesy of Craig Easley.

      Extension of the penis requires appropriate function of the elastic tissues and severe damage prevents the gliding action that permits the free portion of the penis and internal lamina of the prepuce to exit the preputial orifice. Formation of adhesions between the penis, the elastic tissues, and overlying skin following trauma may effectively limit the movement of the penis and result in partial or complete failure of extension. The site of the adhesions may sometimes be identified by a visible deformation of the contour of the overlying skin at the time of attempted erection.

Photo depicts phimosis due to the presence of a penile fibropapilloma larger than the preputial orifice. The tip of the free portion of the penis has been grasped with sponge forceps (a). Following incision of the internal lamina of the prepuce to enlarge the preputial orifice, the penis was extended and the fibropapilloma surgically excised (b).

      Many bulls with phimosis are culled. In cases of preputial stenosis, restoration of the preputial lumen may be accomplished by resection of the compromised tissues and anastomosis of the remaining prepuce if sufficient healthy preputial tissues remain. Similarly, surgical scar revision can be useful for restoring the integrity of the preputial lumen when the amount of healthy preputial skin is insufficient for preputial resection. Both techniques are described in Chapter 19. No treatment is effective if adhesions of the elastic tissues are severe.

      Avulsion of the Prepuce