Sort young cows from mature cows
Dr. Glenn Selk, Extension Cattle Specialist at Oklahoma State University
First calf heifers have historically been the toughest females on the ranch to get rebred. They are being asked to continue to grow, produce milk, repair the reproductive tract, and have enough stored body energy (fat) to return to heat cycles in a short time frame. Two-year old cows must fill all of these energy demands at a time when their mouth is going through the transition from baby teeth to adult teeth.
If these young cows are pastured with the larger, older cows in the herd, they very likely will be pushed aside when the supplements are being fed in the bunk or on the ground. The result of these adverse conditions for young cows very often is a lack of feed intake and lowered body condition. Of course, lowered body condition in turn results in delayed return to heat cycles and a later calf crop or smaller calf crop the following year.
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