Matching the number of cattle to the ranch's feed resources is a constant challenge for cow-calf producers, as they strive to maintain cow numbers to match their marketing plans to the long-term changes in the cattle cycle. Therefore, it is a constant struggle to evaluate the number of replacement heifers that must be developed or purchased to bring into the herd each year.
As a starting place in the effort to answer this question, it is important to look at the “average” cowherd to understand how many cows are in each age category. Kris Ringwall, director of the Dickinson, ND Research and Extension Center, recently reported on the average number of cows in their research herd by age group for the last 20 years
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