AG NOTES

Preparing your cows for a successful breeding season

A successful breeding season actually begins with management decisions made prior to calving. As we move into the winter feeding period, cattlemen need to review their management plan to ensure optimal rebreeding and success. Rebreeding efficiency can be optimized by focusing on body condition score (BCS), early assistance during calving difficulty, scheduling a breeding soundness exam for the herd bulls, planning their herd reproductive health program, and developing a plan to regulate estrus in their first-calf heifers and late calving cows.

Reproductive management begins with evaluation and management of BCS. Body condition score is numerical estimation of the amount of fat on the cow’s body. Body condition score ranges from one to nine; one is emaciated while nine is extremely obese. A change in a single BCS (i.e. four to five) is usually associated with about a 75 pound change in body weight. Evaluation of BCS prior to calving and from calving to breeding is important to ensure reproductive success.

Rebreeding performance of cows is greatly influenced by BCS at calving. Cows that are thin (BCS ˂five) at calving take longer to resume estrous cycles and therefore are delayed in their ability to rebreed. Research has clearly demonstrated that as precalving BCS decreases, the number of days from one calving to the next (calving interval) increases in beef cows.

Management of BCS after calving also impacts rebreeding efficiency. Maintenance requirements for energy and protein increase 25-30 percent for most beef cows after calving. Producers need to plan their supplementation to match or exceed this increased nutrient requirement. Rebreeding efficiency is enhanced in cows that calved thin if their energy intake is increased. Although the best management plan is to calve cows in a BCS of five plus, increasing the energy to cows that are thin at calving can boost reproductive performance.

Dystocia (calving problems) can severely delay the onset of estrus after calving. Research shows that for every hour a female is in stage two active labor there is a four day delay in the resumption of estrous cycles after calving.

One overlooked management tool that can improve reproductive performance is breeding soundness exams in bulls. Think of breeding soundness exams as breeding season insurance. These exams are a low-cost method of insuring that your bull is capable of breeding. Examine bulls for breeding soundness about 30 days before they are turned out.

Several disease are associated with reproductive loss (lepto, BVD, vibrio, trich, etc). The main problem is that most reproductive loss due to disease is subtle and farmers don’t notice the loss unless they have a massive failure. Most cattlemen are not aware of their losses due to abortion. Work with your local veterinarian to develop an annual vaccination plan to enhance reproductive success.

Managing for reproductive success actually begins at calving. Cows need to calve with a minimum BCS of five and with little assistance. Effective planning for reproductive health and management plan for limiting the impact of anestrus will ensure that cattlemen are happy, at the end of the breeding season.

Educational programs of the Kentucky Cooperative Extension Service serve all people regardless of economic or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, gender identity, gender expression, pregnancy, marital status, genetic information, age, veteran status, or physical or mental disability.  University of Kentucky, Kentucky State University, U.S. Department of Agriculture, and Kentucky Counties, Cooperating.

Jerry Little, County Extension Agent for Agriculture/Natural Resources