Linear Appraisal

A Linear Appraisal Score that is 91 VEEE means that the overall quality of the animal was considered 91% of Ideal based on major category scores that were Very Good in General Appearance, Excellent in Dairy Character, Excellent in Body Capacity, and Excellent in Mammary System. However, there is much more to the Linear Appraisal System.

Linear Appraisal actually consists of 3 parts:

•     A Final Score based on an Evaluation of the overall quality of an animal in each of 4 major categories:

• General Appearance  (35% of the Final Score)

• Dairy Character  (20% of the Final Score)

• Body Capacity  (10% of the Final Score)

• Mammary System  (35% of the Final Score)

             Based on the following analyses of quality:

•     E = Excellent @ 90% or greater of ideal

•     V = Very Good @ 85-89%

•     + = Good Plus @ 80-84%

•     A = Acceptable @ 70-79%    

•     F = Fair @ 60-69%

•     P = Poor @ 59% or less

•     An evaluation of 13 traits on a linear scale (the most important analysis for most breeders)
          Examples are rump width, udder depth,  & set to rear legs

•     A coding of particular traits that do not fit a linear scale appraisal system
          Examples are pastern strength, turned out feet, etc.

This linear system assumes that the physical traits we see in an animal represent their genetic background. If five females out of five different dams are sired by one buck and all are taller than their dams, we conclude that the height of those does is a particular trait thrown by that one buck. By using numerical values between 1 and 50 to describe physical traits, we have a way to measure the influence of genetics on those traits to determine the influence of a sire. This is an artificial method but it does allow us to visualize and calculate differences.

As an example, if we measure the rump width of 1000 does, we can calculate an average rump width by totaling all of those measurements and dividing by 1000. If the average rump width was 7 inches, and we assign a mid-range score of 25 to that rump width, then the rump that is wider at 9" could be assigned a score of 45 and a rump that is 5 inches wide would be assigned a score of 15. Likewise, a doe of average strength would have a strength score of 25, while an extremely strong doe is assigned a strength score of 45 and an extremely frail doe would have a strength score of 15. And so it goes for 13 basic physical traits of dairy goats, some of which are actual measurements and others, which are somewhat more subjective in evaluation.