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Bulls most commonly sustain injuries to the prepuce during breeding. The extent of disruption of the surface epithelium and peri‐penile elastic tissue determines the prognosis and therapeutic approach for returning the bull to breeding soundness. The veterinarian should understand the etiology of preputial injury and the therapeutic options for the animal [4, 6].

Primary preputial prolapse in the bull is usually a sequela to breeding injury, frostbite, or balanoposthitis caused by herpesvirus infection (infectious bovine rhinotracheitis/infectious pustular vulvovaginitis, or IBR‐IPV). Secondary preputial prolapse is often seen with penile hematoma or urethral rupture. Bulls suffering preputial frostbite may undergo considerable necrosis of the preputial epithelium and heal with mild to severe preputial stenosis (Figure 19.13). IBR‐IPV most commonly affects young bulls and the prepuce may be extremely edematous, with vesicles or pustules on the preputial epithelium. These bulls usually respond well to sexual rest, application of emollient ointments, and conservative therapy, which may include hydrotherapy and support bandaging.

Figure 19.13 Severe preputial stenosis due to frostbite.

Laceration of the prepuce of Bos taurus breeds usually does not lead to preputial prolapse. The damaged prepuce is typically withdrawn into the sheath and swelling of the sheath may or may not be observable. Minor injuries are often unnoticed, heal without complication, and result in only minor superficial scarring [4,6–9]. However, it should be noted that occasionally the resultant scar tissue will create pain during breeding [1]. In this case a scar revision procedure can be utilized. Some B. taurus bulls with preputial laceration develop paraphimosis, where the damaged tissues will not allow retraction of the penis into the sheath (Figure 19.14). Alternatively, some bulls that do retract the penis into the sheath develop phimosis due to stricture of the injured prepuce (Figures 19.13 and 19.15).

Figure 19.14 Paraphimosis secondary to preputial laceration.

Figure 19.15 Phimosis secondary to preputial laceration.

Laceration of the prepuce with subsequent preputial prolapse occurs more commonly in Bos indicus breeds due to their pendulous sheath, redundant preputial tissue, and larger preputial orifice [4, 6, 10]. Additionally, when combined with cattle that are polled, this condition is exacerbated due to the fact that polled cattle breeds typically lack the preputial retractor muscle. During breeding, the excess prepuce is forced caudally and forms a collar at the preputial orifice when intromission is achieved. This collar of prepuce becomes forcefully entrapped between the bull's abdomen and the vulva and pelvis of the cow during the ejaculatory lunge, with subsequent contusion and occasionally laceration or bursting of the skin on the longitudinal axis of the ventral aspect of the prepuce. Edema quickly develops in the traumatized skin and underlying elastic tissue, leading to prolapse of the prepuce. As the penis is withdrawn into the preputial cavity the longitudinal tear assumes a transverse orientation that effectively shortens the ventral aspect of the prepuce. As edema accumulates in the damaged tissues the prolapsed prepuce increases in size and assumes the appearance of an elephant's trunk, with the lumen of the prepuce directed caudally (Figure 19.16). The laceration is evident as a transverse wound on the caudal aspect of the prolapsed tissues (Figure 19.17), with the severity of preputial tissue damage a result of both severity and duration of the injury (Figures 19.18–19.20).

Figure 19.16 Preputial prolapse on presentation. Note “elephant trunk” appearance.

Figure 19.17 Moderately severe preputial prolapse with tear on ventral aspect that has assumed a transverse orientation.

Figure 19.18 Fresh preputial prolapse with edema and minimal necrosis.

Figure 19.19 Preputial prolapse with severe laceration and minimal edema.

Figure 19.20 Preputial prolapse with laceration and severe edema.