Selecting and managing cleanup bulls
The role of a cleanup bull can sometimes be under appreciated. But a cleanup bull is a part of a livestock producer’s herd that should garner appreciation, careful selection and diligent care.
A cleanup bull’s job is just what his title insinuates – producers utilize cleanup bulls to breed cows and heifers that fail to conceive or maintain pregnancy following AI. “Economic sustainability is highly dependent on cows producing a calf every year,” Shane Gadberry, Ph.D., University of Arkansas Division of Agriculture, said. “Cleanup bulls help fill the gap between AI success rate and the overall pregnancy rate potential of the herd within a set breeding season.”
When utilizing a cleanup bull, livestock specialists recommend taking note of the limited opportunities a cleanup bull will have during breeding season to breed a heifer or cow. “Keep in mind that a cow’s estrous cycle is 21 days, so within a set breeding season, there may only be two to four opportunities for that cow to breed,” Gadberry explained.
Experts recommend livestock producers take time to research and evaluate potential cleanup bulls. “I tell folks to buy a cleanup bull as if he’s going to sire fifty percent of your calf crop,” Eldon Cole, University of Missouri Extension, livestock field specialist, stated. “Just because he’s a cleanup bull doesn’t mean he might not have some traits you can use as a replacement heifer producer or even an excellent performance and carcass sire.”
When producers use AI breeding, they have the opportunity to target specific traits in a sire for individual females. However, when selecting a cleanup bull, the entire herd must be considered. For example, smaller farms that operate with a single cleanup sire may have to focus on calving ease traits, if the operation uses the cleanup bull to breed both mature cows and replacement heifers.
Other factors to consider in a cleanup bull is his genetic impact on economically important traits. In many cattle operations replacement heifers are retained from AI sired mature cows. In most cases the AI sire possesses greater genetic merit than the cleanup sire. The replacement heifers out of the AI sire are typically older at weaning and first breeding.
In a cattle operation where replacement heifers are not retained as future females in the herd, producers may choose a cleanup bull with highly desirable terminal traits. “When there is no intent to keep replacement heifers from cleanup sires, cattle producers may focus on economically important terminal traits like growth and size in their cleanup sires,” Gadberry explained. “It’s not uncommon to see a cattle producer even choose a different sire breed for a cleanup sire.”
Selecting a cleanup bull from the same or similar climate is another consideration when purchasing a cleanup bull.
“Remember, if you have “hot” fescue the cleanup bull will be expected to do the impossible, so make sure his genetics will perform well in adverse, fescue conditions,” Cole advised. Cole added the cleanup sire should be an early hair shedder and not stand in the water all day.
The management of cleanup sires includes care for their condition, health and reproductive soundness. “One-third or more of the calf crop is relying on the success of the cleanup bull,” Gadberry said.
Cleanup bulls should undergo a breeding soundness exam. “He needs to be given a breeding soundness exam because he probably will be called upon to breed your hard-to-breed females,” Cole said. “He possibly will also be breeding during very hot, dry weather for spring calving herds or in cold, icy weather for fall.” Additionally, cleanup bulls that are purchased should be tested for trichomoniasis (Trich).
Livestock experts state one management practice to consider is leasing cleanup bulls. “Easier said than done, but with AI, the amount of bull power needed has already been greatly reduced and the bulls that are needed may only work 10 weeks or less during the year, when only used for one season,” Gadberry explained.
Producers should also keep in mind that when they weigh and evaluate their calf crop, the calves sired by the cleanup bulls will weigh significantly less than the AI sired calves because they are often two to three weeks younger. This will also depend on whether or not the producer used a second AI service.
When breeding season is over, the cleanup bulls should be taken out of the pasture and given time to recuperate.