Replacement Heifers

Management Objective: To select and grow heifers to produce cows that will have long productive lives.

Points to Remember

• To complete growth to maturity on schedule, heifers need extra care until their second calf.
• The number of heifers selected now will dictate the number of cows that can be culled a year from now.
• More replacement heifers will be needed if the herd is being reorganized by culling late calving cows to shorten the calving season.
• Heifers large at weaning will retain their advantage throughout life.
• Proper feeding in the first winter is critical to the cows' eventual development.
• Early cycling in heifers depends on age and weight at the time of the start of the breeding season,
• Heifers having calves in the first three weeks of the calving season will outproduce heifers that calve later in the calving season.
• Heifers need more time to start cycling after their first calf than mature cows. Many breeders therefore start the breeding season for replacement heifers three weeks before the cows.
• Selecting and breeding more replacement heifers allows a manager to put more selection pressure on the cow herd for fertility and higher weaning weights.

• Extra feed is needed by younger females. Replacement heifers should be fed separately and given extra feed from weaning until after their second breeding period.
• Keep enough replacements so that any cow that needs culling can be replaced.
• Cows calving beyond 60 days in the calving season should be replaced by heifers calving in the first 21 days.
• Calve heifers 21 days ahead of the cow herd to allow them more time to begin cycling before the breeding season begins.
• Calving problems can be minimized by selecting bulls with lighter calf birth weights, although this will compromise growth potential and heavier weaning weights.

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