As we all know, breeding season is around the corner. With spring arriving, plans for the breeding season and what it will entail are on everyone’s mind. However, let’s not forget about our replacement heifers. As you prepare for the breeding season, proper management of your replacement heifers will provide opportunities to enhance breeding performance, in-herd longevity and potential uniformity in genetic management and value. The management of replacement heifers is sometimes considered an exact science and predicting the performance of a replacement in any given management system is controlled by several factors; such as genetics of an animal, environment of origin, heifer management from weaning to breeding, production goals and economics.

By evaluating each heifer’s stage of development prior to the breeding season, following this checklist will provide each heifer an opportunity to conceive.

• Target your heifers to be at a body condition score of 6 to 6.5 and weigh 65% of their mature body weight at the beginning of the breeding season to allow those heifers to be nutritionally on target prior to breeding.
• Collect pelvic measurements (estimate of internal pelvic area) on each heifer 30 to 60 days prior to breeding to be used as a selection criterion in replacement heifers. Internal pelvic area influences the incidence and degree of calving difficulty in first-calf heifers.
• Collect reproductive tract scores on each heifer 30 to 60 days prior to breeding or visually observe for estrus activity for five consecutive days. Reproductive tract scoring estimates the pubertal status of a heifer by rectal palpation of the uterine horns and ovary. Visual observation of estrus activity can be used to indicate the percent of heifers cycling prior to the breeding season.
• Nutrient demands are higher in first-calf heifers during postpartum recovery because of lactation, maintenance and growth. Moving your replacement heifer breeding season 20 to 30 days prior to your mature cow herd breeding season will allow first-calf heifers more time for postpartum recovery prior to their second breeding season.
• Prior to breeding, managing your lighter or prepubertal heifers separately and culling heifers showing noticeable signs of unsoundness resulting from lameness or chronic illness will save a producer cost, labor, time and headaches.

Managing your replacement heifers comes early in a heifer’s developing stage. At times, producers don’t realize their inputs into a developing heifer; however, on average it takes 4 to 6 years of production from that heifer to return a profit. So the management systems you implement for your replacement heifers have a major impact on reproductive performance, longevity of replacements into the herd and economic viability of the operation.

For more information on Minnesota Cow/Calf reference materials or Minnesota Beef Team events go to: www.extension.umn.edu/beef/.