Fall is nearly upon us and fall calving is in full swing.
Now is the time to start thinking about your bull power for breeding season coming in approximately two months. Too many times I have seen cattlemen plan and strategize for handling cows and heifers for the upcoming breeding season, only to forget that their bulls. I would suggest, rather than a last minute rush, that you start planning now to make sure the bulls are ready to perform up to expectations later this fall.
First, how many bulls do I need to get my cows and heifers bred? There have been many recommendations for this number. In a 60-day breeding season, I recommend yearling bulls be expected to cover between 15 and 20 cows, 2-year-old bulls should cover between 20 and 30 cows, and bulls 3 years or older should cover between 30 and 40 cows. These numbers can vary, and the number of females per bull should decrease if synchronization is used in the herd. Herds using short breeding seasons, less than 60 days, should consider smaller female to male ratios.
A second consideration is the condition and health of the bulls. Bulls need to have good body condition at the start of the breeding season in order to maintain fertility and conception rates. I recommend bulls should body condition score (BCS) around 6. A little heavier is OK, but bulls that are too heavy are not as aggressive and have more feet and leg problems. Thin bulls are also a problem, as under conditioned bulls often do not have the stamina to breed cows for an entire breeding season, and fertility often decreases as the breeding season progresses. Plan to feed your bulls well during the breeding season; it takes a lot of energy chasing cows in heat!
Another part of the health equation is to evaluate the mobility of your bulls. Diseased feet and other orthopedic problems involving the legs are one of the top problems I see when evaluating poor breeding performance. Bulls that have impaired mobility do not mount cows normally or get cows pregnant. Important things to look for include swollen or painful feet, grown out feet that need proper trimming, and swollen joints. Have your veterinarian examine any bull now that appears to have a problem to determine if the injury or disease can be treated in time for the bull to be used or if the injury cannot be treated successfully.
The third area to evaluate is the reproductive tract of the bull. This traditionally means a semen evaluation performed by your veterinarian. This should be done within 60 days of turnout with cows. Have your bulls tested early enough that if problems are found, there is time to either recheck the bull in question or replace the bull. Occasionally bulls are difficult to collect, so giving a bull one to two weeks before rechecking can often result in a normal semen sample. Fertility evaluations should include not only an examination of the sperm produced, but also visual and manual exam of the penis, the prepuce, testicles and pelvic accessory glands. Palpate the testicles for symmetry and texture. It is often a good idea to have older bulls, especially those with marginal semen production, palpated to examine the accessory glands for swelling and/or infection.
