Now is the time to body condition score (BCS) beef cows and heifers that will be calving in the fall. Bob Larson, DVM, PhD, Dipl. ACT, Dipl. ACVPM, Kansas State University, says for cows, his target is BCS 5 (minimum 4 for a few individuals as long as most of group is 5 or greater). For heifers, his target is BCS 6 (minimum 5 for a few individuals as long as most of the group is 6).
The forage quality and quantity for fall-calving cows leading up to calving should be sufficient to maintain or gain body condition – if is inadequate, the forage must be supplemented to meet energy and protein requirements, Larson says. “The nutrient requirements are the same with both spring-calving cows and fall-calving cows, but in the same geographic area, it may be easier or more difficult for fall calving cows to be in adequate body condition going into calving compared to spring-calving cows.”
This year has seen challenges in some area due to drought or even fires that have left pastures in poor condition. If protein level in the available forage is low (i.e. approximately less than 7% crude protein), protein should be supplemented to increase forage intake and digestibility, Larson says. “If forage protein is adequate, but the available forage cannot provide the necessary calories to maintain or add body condition, energy may need to be supplemented.” Energy in the form of starch should be limited to about the equivalent of 4 lbs. of corn (as fed). By-product feeds frequently provide calories primarily from cellulose rather than starch and can be fed at higher levels without inhibiting forage digestibility.
Fall-calving cows and heifers that calve in poor condition can have a difficult time adding body condition. “If additional calories are provided once lactation has begun, much of the additional energy will be partitioned to lactation rather than to restore body reserves and the resumption of cycling is delayed,” Larson explains. “The best time to add body condition to thin heifers or cows is before they calve.”
Overly thin cows are also at increased risk for dystocia and poorer performing calves (health and weaning weight) and are likely to not resume estrous cycles in a timely manner.