Joe C. Paschal
Professor and Extension Livestock Specialist
Corpus Christi, TX
A profitable beef operation involves producing the maximum pounds of beef at the least possible cost. In many beef operations calves are weaned at a given time; therefore, cows calving late in the calving season wean smaller calves than do cows calving earlier. In addition to weaning heavier calves, cows calving early in the calving season have better rebreeding rates than cows calving late in the calving season. Good heifer management may be the most critical management tool. It produces a uniform group of heifers that, when given an opportunity to conceive early in the first breeding season, will calve early in the first calving season. These heifers usually remain early calvers throughout their productive life and wean the heaviest calves.
I. Heifer selection at weaning
A. Retain only heifers with heavy actual weaning weights.
B. Retain 10 to 15 percent more heifers than the replacement rate requires.
C. Do not retain heifers with structural defects.
D. Do not select heifers based only on visual character and femininity.
II. Management from weaning until breeding
A. Weigh all heifers at weaning.
B. Determine the desired target weight by the start of breeding.
C. Calculate necessary daily weight gain per heifer from weaning to start of breeding.
D. Design rations to achieve desired daily gain.
III. Management at breeding
A. Remove heifers showing noticeable unsoundness resulting from lameness or chronic illness.
B. Initiate breeding 20 to 30 days before the start of the breeding season in the mature cow herd.
C. Mate heifers to bulls with a history of calving ease.
D. Breed for no more than 70 days and then remove bulls from the herd.
IV. Management after breeding
A. Pregnancy test 60 to 65 days after the end of breeding.
B. Retain those heifers that conceived.
C. Market all open heifers to your best advantage.
D. Beginning 60 to 90 days before the start of calving, separate pregnant heifers from the mature cow herd.
E. Feed heifers (or allow adequate grazing) to weigh at least 85 to 90 percent of their expected mature weight by the start of first calving.
F. By the start of calving, heifers need a body condition (fat stores) score of at least 5 or 6.
V. Management at calving
A. Hold heifers in an easily accessible pasture for observation and assistance during calving.
B. Check heifers three or four times a day.
C. Continue to feed heifers to maintain their body condition through calving and rebreeding.
VI. Management during the second breeding season
A. If first calf heifers are in poor body condition and/or you are short of feed, consider early weaning of their calves by 30 to 60 days of age; or, use once-a-day suckling by the time calves are 30 days old.
B. Breed for 60 to 80 days, starting the breeding season at the same time as the mature cows.
C. Cull all first-calf heifers that fail to re-breed.
Breeding virgin heifers earlier than the mature cow herd, providing proper nutrition before and after calving, separating heifers from mature cows, weaning early and using once-a-day suckling are effective methods of improving reproductive performance of heifers.