John F. Grimes, OSU Extension Beef Coordinator

A few years ago, I wrote an article relating to shortening the breeding season titled “Utilize the K.I.S.S. Method!” The acronym used in the title of that article referred to my preference for the appropriate length of the beef cattle calving season and imminent breeding season. In this situation, K.I.S.S. refers to “Keep It Short and Sweet!” In this article, I want to remind you of the primary advantages of a shorter breeding season. I also want to discuss a potential marketing advantage of actually lengthening the breeding season.

There can be compelling arguments to make when choosing the best calving season for a particular operation. It is my experience that there is no single best choice for a calving season for all operations. Each operation is unique as to the assets available to devote to the cattle operation including labor, facilities, feedstuffs, etc. Ultimately, the selection of your particular calving season should be determined by the likelihood of achieving the highest conception rates and calf crop percentage weaned based on your available resources.

Regardless of when you calve, there is little justification for a lengthy breeding season. If you are currently involved in a longer breeding season, there are valid economic and management reasons to make a change. Research published by researchers at Oklahoma State University and Texas A & M found a positive relationship between number of days of the breeding season and the production cost per hundredweight of calf weaned. They also reported a negative relationship between number of days of the breeding season and pounds of calf weaned per cow per year.

A 60-day breeding season is an ideal goal to shoot for and it is hard to justify any calving season longer than 90 days. Shortening a calving season requires a little discipline, a commitment to some basic facilities, some rigid culling, and a willingness to use technology and other resources available. It may be impractical to move to a 60 – 90 day calving window in one year but there is no time like the present to start working towards this positive change.

Nearly every management decision associated with the cowherd is simplified with a shorter calving season. Herd health, nutritional, and reproductive management are much easier when all cows are in a similar stage of production. Restricting the breeding season to 60 to 90 days will produce a more uniform calf crop, which enhances marketing opportunities. It is easier to match up your forage supply with the nutritional demands of your herd when all animals are in a similar production cycle. Vaccination programs are more effective when animals in the breeding herd are in a similar reproductive status.

A more concentrated calving season is important for the smaller or part-time producers who have major time restrictions in their daily lives. I do not know of any producer that enjoys the stress and worry of calving season over an extended period. This is especially true if calving season comes during inclement weather and you are away from the farm for long stretches of time during an average day.

Over the years, I have heard many excuses for why producers have lengthy or even year-round calving. One excuse frequently heard relates to the lack of facilities to maintain herd bulls away from the cowherd for any length of time. I personally believe a facility to maintain a herd bull separate from the cows should be a requirement for any cow-calf operation. These facilities can be simple yet secure and not require a large financial commitment from the producer. This simple management step would go a long way towards shortening the length of the calving season across the state.

Dr. Les Anderson, Beef Extension Specialist, University of Kentucky and a frequent contributor to the Ohio BEEF Cattle letter, reminds us that there are several heat synchronization programs available to producers. These tools do not have to be used exclusively in artificial insemination programs and can improve conception rates in herds using natural service sires.

One method to improve reproductive performance of your cowherd is to synchronize estrus prior to bull turn out. Studies conducted at UK have demonstrated that treatment of cows with a CIDR device for 7 days before natural service can have increase pregnancy rate 5-15% and can increase the proportion of cows that calve in the first 30 days of the breeding season. Anderson’s data indicates that the CIDR devices only need to be inserted in cows that are likely to have trouble conceiving early in a breeding season; late-calvers and two-year old cows. By “targeting” our reproductive management to these cows, one can improve the whole herd performance and limit our input costs.

A shorter calving season will eventually lead to greater efficiencies in reproduction rates. Palpate shortly after the conclusion of the breeding season and cull heifers and cows that do not conceive within your given calving season and do not look back. Keep daughters of the cows that are bred early each calving season. If necessary, buy bred females that calve within your desired window to replace the open females. Implementation of these practices will certainly improve your herd’s reproductive performance over time.

After discussing all of the merits a shorter calving season, I am going to offer you one legitimate reason for stretching out the breeding season. By leaving the herd bull out for an extra cycle or two, you may get a few more females bred over the breeding season. If you extend the breeding season, timely use of pregnancy diagnosis is very important. Traditional palpation or ultrasound should be used to determine which females are pregnant for a desired 60 – 90 day calving season.

Any females that become pregnant outside of the desired calving window can be merchandised as bred females to other producers and will certainly be more valuable than an open female that is destined to be culled. Remember that if you stretch out your intended breeding season, do not be afraid to cut it back to a more manageable length. We will be discussing an exciting marketing opportunity for young bred females in the near future.