Bovine Reproduction. Группа авторов

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tissues and assist with resorption of the edema and blood clot within the elastic tissues. If preputial prolapse is present, an emollient ointment should be applied and the protruding tissues protected with a support bandage or sling to prevent secondary trauma. The bull should have a complete BBSE prior to returning to service.

Photo depicts rent in tunica albuginea.

      Deviations of the penis may occasionally prevent intromission and coitus. Bovine penile deviations are classified as spiral (corkscrew), ventral, or S‐shaped [415–19]. Typically, bulls have had one or more successful breeding seasons prior to development of penile deviations with usually no known history of previous penile injury. Most bulls with these conditions are three or four years old and occasionally a bull over that age will develop penile deviation.

      Spiral Deviation

      Spiral deviation of the penis occurs more commonly than either ventral or S‐shaped deviations. One potential etiology involves malfunction of the dorsal apical ligament. The apical ligament, a thick collagen band, arises from the dorsum of the tunica albuginea about 2.5 cm proximal to the distal end of the prepuce and inserts into the tunica albuginea near the distal end of the corpus cavernosum penis (CCP). The function of this structure is to help maintain the shape of the penis during erection [17]. Historically, spiral deviations were considered to result from a short or inadequate apical ligament that slipped off to the left side of the penis at peak erection, allowing the penis to spiral and therefore preventing intromission [16–18].

      However, the rapidly coordinated events leading to erection and the high maximum pressures within the CCP at ejaculation suggest that affected bulls may prematurely achieve maximum erection pressures prior to intromission. This suggestion may be supported by the fact that the penis of many normal bulls likely develops a spiral orientation in a cow's vagina during ejaculation [19]. Although the definitive cause of spiral deviations remains uncertain, apical ligament malfunction and premature achievement of high CCP pressure may be involved.

Photo depicts spiral deviation.

      Bulls with spiral deviation of the penis are most often three years old and have had a successful previous breeding season. Development of this condition may be insidious, occurring intermittently at first, then more consistently as breeding efforts continue. Therefore several test matings may be necessary to confirm the diagnosis. In B. indicus bulls the deviation may occur prior to penile extension such that the deviation remains hidden within the bull's pendulous sheath and excessive prepuce. For bulls with this sheath conformation, manual retraction of the prepuce during attempted breeding may be necessary to differentiate from erection or other causes of penile extension failure.

      Ventral Penile Deviation

      Ventral penile deviation occurs much less commonly than spiral deviation and the etiology is uncertain. Ventral deviations may occur as a result of altered blood flow through the ventral portion of the CCP or due to stretching or injury of the apical ligament, both of which probably result from chronic traumatic injury [1, 17, 18].

Photo depicts ventral deviation.