Last month’s column focused on heifer selection. This month, the focus will be on proper development of those heifers for both short- and long-term success. Heifer development includes getting heifers ready to breed and also making sure bred heifers are developed properly.
Opinions vary on the minimum weight that heifers should be developed to before the breeding season. In most situations, developing heifers to reach 65% of their mature bodyweight is a good approach. For these purposes, the weight of a 5- to 10-year-old cow that is in a body condition score (BCS) of 5 and is open or in the first stage of gestation can be used as the mature weight. So, if heifers will develop into 1,400-pound cows, they should weigh 910 pounds or more prior to the breeding season. If they will become 1,100-pound cows, then 715 pounds would be the target weight prior to breeding.
Heifer development is not over once the breeding season ends. Bred heifers then need to be developed to reach 85% of their mature weight prior to calving. Proper development of bred heifers reduces calving problems, optimizes bred-back rates and generally increases calf weaning weights. Underfeeding bred heifers can actually increase calving problems and reduce future reproduction.
Based on the weight of heifers at weaning, a 65% pre-breeding target and the 85% pre-calving target minimum weight gains for each development stage can be calculated. The example below shows target weights and average daily gain (ADG) needed for each stage.
- 1,300-pound estimated mature weight
- 7 months old and 585 pounds at weaning
- 14.5 months old and 845 pounds at breeding
- 24 months old and 1,105 pounds at calving
- ADG from weaning to breeding (230 days): 1.13 pounds
- ADG from breeding to calving (283 days): 0.92 pound
