some body condition. Starting with a 6 to 9 body condition score will allow some loss of condition without an effect on overall health and prevent early over-conditioning, which can also alter with sperm production and ability to efficiently mount cows. Breeding Injuries • Penile Hematoma – One of the most serious injuries a bull can sustain during breeding is a penile hematoma (“broken penis”). This occurs when a bull is mounting a cow and, instead of entering the vulva, thrusts his penis against her hind legs or hip. The penis bends and ruptures, leading to significant bleeding outside of the penis and the formation of a hematoma (under the skin and tissue of the prepuce). You typically won’t see the injury occur, but will immediately see a large swelling between the bull’s scrotum and the prepuce. The bull will not be able to breed cows. This should be addressed as soon as it is detected, and working with your veterinarian there are various medical and surgical treatments that can be discussed. Since there is often a guarded prognosis for return to function, culling and replacing the bull may be the best economic decision but will depend on his value and genetic merit. • Preputial (Sheath) Prolapse – This can occur in any breed, but are more common in bos indicusinfluenced breeds with a more pendulous prepuce (Brahman, Brangus, etc.). Whether they injure their prepuce by direct trauma (often by stepping on it) or through a breeding injury, the consequences are the same. Swelling occurs quickly as it is the lowest part of a bull’s abdomen, and subsequent tissue infection can lead to scar tissue formation. The penis is trapped inside the prepuce, and breeding is not possible. This swelling and prolapse can be treated with supportive care (local wound care, antibiotics and
anti-inflammatory drugs), but occasionally surgery is required to remove the scar tissue preventing normal function. There is generally a better prognosis for return to breeding than with penile hematomas. Managing and treating breeding injuries can be difficult depending on the individual bull and the injury sustained. This is an economic decision to be discussed between you and your veterinarian. Depending on the value of the bull and the severity of the injury, replacing the bull may prove to be the most economically justifiable course of action. Post-Breeding When removing bulls from the cows examine them for any abnormalities in their overall health, lameness, penis/prepuce, etc. Immediately following breeding is the opportune time to address health concerns with your veterinarian and decide which bulls to maintain until the next breeding season. Ranches that manage two separate breeding/calving seasons (such as spring and fall calving) will have different demands and a shorter time period to rejuvenate bulls than once yearly calving operations. This is a time for bulls to rest, restore adequate body condition and prepare for the next breeding season that should not be ignored. Maintenance energy, protein and mineral requirements should be met, and the bulls should be kept separate from other bulls of unknown vaccination, trichomonas and health status to ensure the health of your herd. Herd bulls are critical to the success of the herd and require yearlong attention to keep your investment ready for the next breeding season. Should you have questions regarding developing a specific health plan for your bulls or to address bull injuries consult your veterinarian. Additionally, the UC Davis School of Veterinary Medicine is available to assess bull injuries using the latest technology.
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