ANGUS BEEF BULLETIN EXTRA

December 7, 2021 | Vol. 14 : No. 11

Body Condition Scoring of Cows

Producers should target a BCS of 5.5 for spring-calving cows.

The body condition scoring system (BCS) is used to assess body energy reserves in beef cows. The BCS system used for beef cattle ranges from 1 to 9. A score of 1 indicates cows that are thin and emaciated; cows of BCS 9 are fat and obese. Pictures and definitions of the BCS system can be found in Chapter 20 of the 8th edition of the OSU Beef Cattle Manual or at http://www.cowbcs.info/photogallery.html.

When condition-scoring cows, producers should look beyond age, frame size, depth, length, pregnancy status and hair coat. The condition-scoring system is intended to provide a consistent system to quantify relative fatness regardless of these other factors that create differences in cows’ appearance.

There is a strong relationship between weight and BCS. For each unit change in BCS, cows should gain or lose approximately 7% of their BCS 5 weight. For example a cow that weighs 1,200 pounds (lb.) at a BCS 5 should reach a BCS of 6 at 1,284 lb. or drop to a BCS 4 at 1,116 lb.

Why is BCS important?
One of the major constraints in the improvement of reproductive efficiency in cows is the length of postpartum anestrous. If cows are to maintain a calving interval of one year, they must breed back within 80-85 days after calving. In both old and young cows, it is well-established that BCS at calving time determines the rebreeding performance of beef cows in the subsequent breeding season.

The process of fetal development, delivering a calf, milk production and repair of the reproductive tract are all physiological stresses.

Cows maintaining body weight, therefore having ample energy reserves before parturition, exhibit estrus sooner than cows losing weight. Body weight change during pregnancy is confounded with fetus and placenta growth. Therefore, the estimation of body fat by use of BCS is more useful in quantifying the energy reserves of beef cows. The process of fetal development, delivering a calf, milk production and repair of the reproductive tract are all physiological stresses. These stresses require the availability and utilization of large quantities of energy to enable cows to rebreed in the required 85 days.

Cold and/or wet weather often faced by spring-calving cows adds additional environmental stress, resulting in energy intake that is below body maintenance needs. The cow compensates by mobilizing stored energy or adipose tissue, which is why adequate BCS at calving is so critical to reproductive performance.

The goal
Producers should manage their calving season, genetics, grazing system, supplementation program and herd health to achieve an average BCS of 5-6 (target 5.5) in the mature cow herd at calving time. The goal for first-calf heifers is a BCS of 6. Typically, the greatest reproductive challenge in beef cattle is the breeding back of 2-year-old females raising their first calf, lactating for the first time and still growing themselves. Accordingly, the higher BCS of 6 is recommended.

Editor’s note: Mark Johnson is an Oklahoma State University Extension beef cattle breeding specialist.