Silveus Ins_bannerBCSC Banner_2022
Advertise With Us Subscribe Today Facebook
Not a member? Membership has its privileges— Register today! • Make SLS your homepage!
home articles Reproduction |

Pay attention to calving distribution

published: April 2nd 2021
by: Igrow

Producers may be knee-deep in calving, or for others it is just around the corner. However, this is a good time to start thinking about the upcoming breeding season and subsequent calving season. The current calving season provides an opportunity to decide if the current calving situation is working well, or if management changes are needed to achieve the desired calving season.
    Most producers keep track of calving records in some fashion. Whether recording in a Red Book, notebook paper, scrap paper, your hand or an app, most producers have an idea of their number of calves born and when. These records can then help determine a calving distribution, and calving distribution can help determine succeeding management strategies. Olivia Amundson, Extension cow/calf field specialist provides insight into calving distribution.
What is calving
    Calving distribution is a measure of number of calves born in 21-day intervals. The length of the estrous cycle of a cow is 21-days; therefore, she has the opportunity to become pregnant every 21 days. Typical benchmarks for an efficient calving distribution are: 63% of the mature cow herd should calve within the first 21 days, 87% by 42 days and 96% by 63 days of the calving season. If less than 60% of the herd is calving in the first 21-days and greater than 25% calving in the second 21-days, then re-evaluation of the herd and management strategies need consideration.
Why is calving
distribution important?
    Calving distribution is a measure of efficiency and management within a herd. Research has demonstrated that heifers born earlier in the calving season are more likely to be cycling at breeding, have greater pregnancy rates and more of those females will calve in the first 21-days of their initial calving season. Steer calves born in the first 21-day period had increased weaning weights, more ideal marbling scores and overall more-positive effects on feedlot and carcass performance.
    While benefits on progeny are beneficial, calving distribution also helps allocate resources, specifically feed and labor needed during the calving season. This provides more focus at time of calving, which can decrease mortality and disease in calves. Focus can then be placed on the cow to ensure that she is being fed appropriately to maintain or increase body condition score prior to the subsequent breeding season.
    Cows that calve late or had a traumatic calving will be at risk of being open the following year. By focusing on calving distribution, it allows management decisions to be made that will focus on maintaining herd numbers with the most fertile, healthy, efficient cows. Allowing late calvers and those that have difficulty calving to fall out of the herd can increase overall herd performance.
Keeping records
    Keeping records is the start to determining a calving distribution. Producers who don’t write down calvings can track distribution by frequently counting the number of calves on the ground. This can give a rough estimate of calves born in each interval.
    Producers who keep records should consider using the Calving Distri-bution Calculator to graph calving distribution, as well as determine the economic impact of the current distribution. The calculator can be downloaded at https://
Management strategies
for a consolidated
calving season
    If consolidating the calving season is a management strategy that needs consideration, there are multiple factors to evaluate.
    Consider how your herd is calving. Are a majority of the females calving in the second interval (22–42 days)? Is there an even spread between intervals, or do cows calve past the third interval (63+ days)? Depending on how the herd is calving, different strategies should be considered.
    First, how do the cows look in terms of body condition? If cows are at a body condition score of less than five, there could be issues with breed up, as well as maintaining a pregnancy. Evaluate the ratio and adjust appropriately. Did heifers calve with the cowherd or separately? If they calved at the same time as the cows, ensure those females are being fed adequately to meet nutrient requirements, since they are still growing themselves.
    Secondly, are pre-breeding vaccinations and overall herd health being taken into consideration? Make certain that pre-breeding vaccinations are occurring at appropriate times. If using Modified Live Vaccines (MLV), make sure they are given according to the label if not earlier. If naïve heifers are receiving MLV too close to breeding, it can negatively impact conception rates. Bulls should complete a breeding soundness exam 60–90 days prior to the breeding season. This will allow for any disease, sperm abnormalities, or physical inabilities to be identified and addressed in a timely manner.
    Consider reproductive technologies, such as estrous synchronization, to consolidate the breeding and subsequent calving season. Estrous synchronization is a great tool to “bunch” the cowherd and can be used with artificial insemination (AI) or natural service  There are multiple options when considering a protocol, but before jumping in, it is important to consider different factors, such as resources, labor and time, not only when implementing the technology, but also at calving time. Do you have enough labor to calve out a large number of cows over a short period of time?
    Multiple factors go into defining a calving season, but through simple record keeping, management decisions can be made to increase herd performance and profitability.

Site:   Home   Publications   Market Reports   Sale Reports   Sale Calendar   Cattle & Service Directory   Full Commodities Report   Services   About Us   Contact Us

Article Categories:   All   Industry News   Herd Health   Feed & Nutrition   Pastures & Forages   Reproduction   Marketing   Columnists   Production   Genetics & Performance   Weather Forecast   Breed News   Producer Feature Stories   Items of Interest   New Products   Recipes

User:   Login   Logout   Register/Profile   Submit Market Report   Submit Sale Report