Every farm relies on replacement heifers for sustainable productivity and profits. If you don’t have enough replacement heifers — or they aren’t developed properly — your farm may struggle. Read on to learn how to choose replacement heifers, how many to keep, and important details about their development and nutrition.

What Are Replacement Heifers

Replacement heifers are the cornerstone of any dairy farm. They are the future of your herd and have the most direct long-term impact on the profitability and sustainability of your operation. The cows you cull must be replaced with new animals, which is where replacement heifers come in.
A replacement heifer is a young female cow explicitly raised to replace older cows in your herd. She is selected based on her genetics, health, and potential for productivity to improve or maintain herd quality.

Critical Considerations for Replacement Heifers

  • Replacement heifers should attain puberty by approximately 12-14 months, conceive at 15 months, and calve around 2 years old.
  • Heifers that calve early during the first calving wean more and heavier calves during life.
  • It’s essential to keep heifers and mature cows on separate diets.
  • Fetal, pre-weaning, weaning, and breed-back phases are critical for replacement heifers.
  • Heifers will still be growing and self-developing while expected to breed and give birth to a calf.
  • First-calf heifer management affects the productivity of its entire lifetime.

How Many Replacement Heifers Should You Keep?

Farmers purchasing replacements or developing them should base the number on their goals. Typically, you need at least the same number of replacement heifers as the number of cows being culled to maintain the herd size. To increase the herd size, you’ll need more replacement heifers than the annually culled cows.

You must also consider the reproductive rate of your mature cows and the upcoming heifers. Cow age, nutrition, and health conditions can reduce the number of calf births. So, you might need more replacement heifers than the number of culled cows.

Choosing Replacement Heifers

Your replacement heifers should have characteristics that allow for a sustainable herd in the long term. So, it’s best to avoid outliers and stick to heifers that can fit your production. Some of the characteristics you should consider are:

  • Reproductive tract scoring that indicates a heritable early puberty.Origins from the herd with more fertility (culled heifers that don’t get pregnant).
  • Milking ability.
  • Optimal weight and size. Extremely heavy or light heifers should be culled.
  • Calving ease. Consider the Calving Ease Maternal (CEM) EPD of sire and Pelic Area of heifers.
  • The udder structure and mammary system.
  • Age, as heifers born early in the calving season had fertile mothers.
  • Avoid stubborn, aggressive, and nervous heifers.
  • Shedding ability since fast-shedding heifers are typically more healthy and fertile.
  • Heifer’s mother. Consider all the qualities and issues you’d typically look for, like temperament, weight, and calving history.

Replacement Heifer Development

The development of replacement heifers can make or break their lifelong productivity. Ensuring your heifers receive quality nutrition and experience optimal weight gain will help you get a better return on investment in their care.

Fetal to Pre-weaning Phase

A proper heifer development plan starts with adequate cow care before she even conceives. Cows should have a good body condition score before, during, and after gestation. Even after the calf’s birth, the dam’s nutrition remains critical for calf development.

You should also avoid overconditioning young heifers. According to Oklahoma State University, some heifers can have a reduced milking ability when mature if they are overly fat as calves. Underfeeding can inhibit development, so a good balance is vital for pre-weaning nutrition.

Replacement heifers also must receive the appropriate vaccination during this period to achieve immunization against diseases like Blackleg and malignant edema.

Weaning to Breeding Phase

At weaning, it’s best to select heifers that have grown well and were born early, as noted by Kansas State University. They are more likely to breed and cycle with higher productivity.

The growing process must allow sufficient gain from weaning to breeding (approx. 13 months). Providing high-quality starter nutrition and forage will help develop productive heifers. Aim for a gain of 1.25-1.75 pounds daily for optimal body conditioning. Most heifer replacements need to gain about 240 lbs between weaning and breeding.

It’s critical to keep heifers separated from the rest of the herd. They can’t compete with mature cows due to their age and size. Likewise, heifers’ pregnancy rates can drop if provided with feed meant for mature cows as it lacks the necessary nutrients.

Nutrition Plays The Key Role In Heifer Development

Pre-weaning, weaning, and post-weaning nutrition management are key to helping replacement heifers reach puberty by 12 months, according to the University of Wisconsin-Madison.

Forage and pasture can sustain about 1.2-1.5 lbs average daily gain (ADG) with good environmental conditions. However, seasonal changes in temperature and rainfall can negatively affect the forage quality. Supplementing forage with quality feed can help meet your ADG goals and improve the ROI of your heifers.

Support the Success of Your Replacement Heifers with Star Blends

Star Blends can work with your nutritionist to provide optimal animal nutrition for your cattle in all life stages, including feed optimized for heifers. Whether you need dairy or beef cattle feed, Star Blends can provide the proper nutrition for your herd’s specific needs.

Ensure your herd’s future is solid and productive. Provide your replacement heifers with the best nutrition at every stage with feed from Star Blends. Explore our tailored feed solutions and give your herd the foundation to thrive. Contact our team of experts today to get started.