Skeletal size
Cattle frame score calculator
Turn a hip height taken at any age from 5 to 21 months into the frame score buyers and breed associations use.
Frame score describes skeletal size from hip height and age. For a bull: frame score = −11.548 + 0.4878 × height − 0.0289 × age + 0.00001947 × age² + 0.0000334 × height × age, with height in inches and age in days. A bull 50 inches at the hip at 12 months is about a frame 5.5.
Example numbers. Change them to your own.
How to measure and read it
- Measure hip height over the hooks. Stand the animal on level, hard ground and measure straight down from the top of the hip, directly over the hook bones.
- Use the exact age. The Beef Improvement Federation equations apply from 5 to 21 months of age.
- Heifers use their own equation. Frame score = −11.7086 + 0.4723 × height − 0.0239 × age + 0.0000146 × age² + 0.0000759 × height × age.
- A frame score should hold with age. An animal that keeps the same frame score as it grows is on a normal growth curve. Nutrition can shift it by a score or more.
What is a frame score in cattle?
A number, usually from 1 to 9, that describes skeletal size based on hip height at a given age. Larger frame scores mean taller cattle that mature later and at heavier weights.
How do you calculate frame score from hip height?
Use the Beef Improvement Federation equations with hip height in inches and age in days. There is one equation for bulls and one for heifers, valid from 5 to 21 months of age.
Is a bigger frame score better?
Not by itself. Frame score describes size, not quality. The right frame depends on the environment, the cow herd and the market the calves are sold into.