At the 2023 Dairy Calf and Heifer Association Annual Conference, two presenters discussed the delicate balance between cost and quality when raising ideal replacement dairy heifers. According to Paul Dyk, a nutritionist with GPS Dairy Consulting, custom heifer growers don't go out of business because they're too expensive, but because they deliver poor-quality animals at freshening. Thus, it's not just about the rearing costs when raising high-quality replacements.

Dr. Michael Overton, technical services veterinarian for Zoetis, agrees with Dyk and suggests that industry trends of trying to shave heifer-rearing expenses via both cheap feedstuffs and early calving age are being called into question. Overton recommends freshening first-calf heifers at 22-24 months of age at 82-85% of projected mature bodyweight, 95% of mature height, and free of lingering health issues.

Dyk advises weighing heifer calves at birth and freshening on the dairy, using the same scale both times. That data should be recorded into a herd management software like Dairy Comp 305. Then, weighing every cow at calving should become a standard practice so dairies can track their animal weight trends over time. For consistent size, the goal should be less than 50 pounds of variance between animals of the same age.

Hitting heavier weights early is worth it, as Dyk shared data showing first-calf heifers that were 100 pounds heavier at first calving produced 5 pounds more milk per day in their first lactations. Overton emphasized that undersized heifers at calving will partition a greater percentage of nutrients toward growth and away from production, compared to well-grown heifers.

While raising a heifer to 1,500 pounds by 22 months of age is more costly than calving them out smaller, it's worth the investment in the long view. Dyk said, "We've become very specific in developing the type and number of replacement heifers needed in the herd. We don't have room for any duds."

The focus should not only be on rearing costs but also on raising high-quality replacements that can reach their full potential in production. By monitoring animal weight trends, ensuring consistent size, and hitting heavier weights early, dairy owners can improve the future productivity of their herd.