Building herds of cows and bulls with the proper form and type sets the stage for healthy, easy keeping and easy calving cows with longevity. Measuring of the many different body parts allows the operator to recognize structural and functional defects, which are genetic defects, and potential problems that arise from improper breeding practices.
Burl Winchester was the man who re-introduced linear measurement back into the United States. An excerpt from a story I ran across about Burl...
"Burl Winchester was curious man from a curious family. Growing up on a very poor farm outside of Clovis, New Mexico, he and his brothers took care of the family livestock. As I remember the story, when they were raising 4H sheep in the 1930s, they decided to start measuring them and recording the measurements in a little note book. They found strong correlations between many of the traits and started organizing them around the edges of the pages (for each Animal) so they could easily compare the measurements to the general condition of different individuals. This led to making the marks on 3 x 5 cards instead of notebook pages so they could easily sort the cards by different traits and compare that to what they were seeing when the looked at the animals. This was the genesis of the spectrofan © cards that are still used today.
Burl extended the use of these cards to cattle and became easily convinced that by selecting and culling based on traits that correlated with such results as grade of meat cuts in carcasses, or mothering ability, winter survivability, one could easily build a herd of very high quality (however on defined that) within just a few generations. By selecting herd bulls and breeding females to meet one’s criteria, the results were demonstrated repeatedly to be dramatic and unquestionable."
We to can use this tool in the development of the cattle that populate our pastures, to breed for a more efficient cow on grass.