Check the body score on young heifers

By Gary Sliworksly
OMAF/MRA Rep.

Most producers manage their heifers to calve as 2-year-olds. The majority of reproductive problems in a herd occur in these younger cattle. It’s easy to understand the extra demands placed upon these younger females. Not only are they providing nutrients for a developing fetus, they are still in the process of new tissue growth for their own bodies. When energy, protein, or other essential nutrients are deficient or marginal, these younger cows are the first ones to exhibit reproductive problems. Calving heifers as 2-year-olds requires adequate body condition.
Body condition at calving is the most reliable indicator of postpartum reproductive performance for the first calf cow. On a scale of 1 to 5, these heifers should have a body condition score of around 3 at calving. Lower pregnancy rates and longer postpartum intervals are exhibited in cows having a body condition score less than this.
It is not recommended to calve heifers with less than the ideal condition score, but it frequently occurs in the industry. Replacement heifers should be bred to calve 30 to 45 days before the calving season of the mature cow herd. This allows for more time between calving and breeding season for them to return to estrus and allows them to conceive early in the breeding season.
Often, cattle producers do not adjust for this extra time interval between calving and breeding of the first-calf cows. Many of these young cows are delayed in rebreeding until late in the breeding season. This results in a younger calf that weighs less at weaning and often leads to the cow being culled because of that low weaning weight. This is not a fault of the cow, it is a fault of the producer’s management. Open or late to calve with the second calf is usually caused by inadequate pre- and postpartum nutrition of the heifer caused by improper management of the herd.
For the best reproduction, manage the young first and second calf females separately from the mature cow herd. A higher plane of nutrition (energy and protein) is required for the younger cow. If the whole herd were fed for the needs of the younger cow, then the mature cows would be overfed and it would be costly for the producer.
Vary the energy consumption to the targeted body condition score. Thin females need to reach a body condition score of 6 during the last third of gestation, while those heifers in moderate to high body condition at 90 days prepartum should only be fed levels to maintain body condition.

Events to Remember
Apr. 9 – New Dairy Barn Open House 10:00 am – 2:00 pm. at the Martin farm NE of Stratton.