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The Usefulness of Linear Measurements to BueLingo Breeders The concept of using linear skeletal measurements to describe cattle has been a part of the beef industry for many years. Measuring the beef cow with a tape and ruler has occupied the time for many researchers and stockmen since frame scoring became a part of our vocabulary in the 1960's. The American Hereford Association and the University of Wisconsin first presented to the industry the frame score concept in 1967, categorizing animals using their height measurement. Basically, if we knew the age of the animal and the height of the animal we could predict the ultimate market weight of that same animal. For a period of time, the beef cattle industry became acutely interested in using frame score as a primary selection tool for determining breeding programs. In some cases, this type of single trait selection without regard for reproduction and product created problems for individual breeders. At the present time, cattlemen are concentrating on using additional selection tools that are more useful in their breeding programs. The underlying reason for using frame scores in selection was that some cattle matured at a lighter weight than desirable and if cattle were fed to a more desirable weight, they were excessively fat. Increasing the frame size of the cattle population therefore was a way to extend the growth curve and therefore increase the weights of cattle when they were ideally ready for slaughter. When cattle are fed to the same fat constant end point (compositional maturity), frame size is the major factor determining finished weight. The following table gives the approximate live and carcass weights for steers and heifers grading USDA choice in each frame score. The carcass weights may vary slightly depending on the dressing percent variation. Cattle that are fatter and/or more heavily muscled will have higher dressing percents increasing carcass weight.
The procedure for determining frame score is relatively easy. A height measurement of the animal is taken at a point directly over the hooks (see diagram). This measurement is combined with the age of the animal to determine the frame score. At any given age, a two inch change in hip height is reflected in a change in frame score. 
The Beef Improvement Federation (BIF) developed and adopted in 1978, the attached standardized frame score system which is recognized by nearly all beef breed associations in the United States. BIF published the following statement as an integral part of the frame scoring report:
The importance of the frame score system for each Buelingo breeder depends on your need to describe cattle in your herd, either for yourself or for those you market cattle to. There is no question that when combined with weight, the frame score of an animal more completely describes the animal than weight alone can do. Knowing both frame size and weight assists in estimating the fatness of an animal without actual visual appraisal. There is a need to raise cattle that fit into specific production systems and have those cattle produce high quality, high cutability carcasses within a window of acceptable weights. Frame scoring can provide the basis for selection by indicating whether emphasis to increase or decrease frame size is necessary. Breeders should never substitute frame scores or linear measurements for reproductive efficiency and performance testing, it should only be used as a helpful tool to accomplish the goals that have been established by the individual breeder. |
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