This article is full of considerations about heifer replacements. It references multiple tools to help with the selection process. Realize that some traditional sire-selection and cow-size criteria may not be appropriate for best-value replacement heifers. Veterinarians and representatives will appreciate this article as they work with herd owners and managers.
Source: Midwest Ag Journal, December 21, 2015, page 20B.
For cow calf producers who sell their calves at weaning, reproductive performance has five times more impact than growth and 10 times more impact than carcass traits on profitability of your enterprise. Therefore, building and selecting as replacement females those individuals which have superior reproductive traits has a huge impact on the economic viability of a cow calf operation. The key traits that impact reproductive performance are fertility, longevity, calving ease, amount of milk, docility, mature weight and growth to weaning or yearling endpoints.