Dosage is a technique for classifying Thoroughbred pedigrees by type using a list of stallions with specific attributes called chefs-de-race. This calculation can idicate whether a horse has the genes to run long or short. The dosage index is the ratio of speed over stamina.

Difficulty Level: Average      Time Required: 10 minutes

1. Obtain a 4 generation pedigree of the horse in question.
2. Look up the latest list of Chefs-de-race.
3. Determine if the 1st generation sire is a chef-de-race. If so, place a total of 16 points in the aptitudinal categories for which he is a chef. If only one, then all 16 go there, if two then split it with 8 in each.
4. Determine if the 2nd generation sires are chefs-de-race. If so, place a total of 8 points each in the aptitudinal categories for which each is a chef. If only one, then all 8 go there, if two then split it with 4 in each.
5. Determine if the 3rd generation sires are chefs-de-race. If so, place a total of 4 points each in the aptitudinal categories for which each is a chef. If only one, then all 4 go there, if two then split it with 2 in each.
6. Determine if the 4th generation sires are chefs-de-race. If so, place a total of 2 points each in the aptitudinal categories for which each is a chef. If only one, then all 2 go there, if two then split it with 1 in each.
7. Total the points in each aptitudinal group to get the dosage profile.
8. Add together the first two components (Brilliant and Intermediate) plus half the third (Classc) and divide by the total of the other half of Classic plus the last two components (Solid and Professional). This is the dosage index.
9. Add twice the Brilliant points plus the Intermediate points minus the Solid points minus twice the Professional points then divide that number by the total number of points in the DP to get the center of distribution.
   

1. A horse who can run 10 furlongs will generally have a dosage index of 4.0 or less and a center of distribution of 1.0 to -1.0.
2. The ideal dosage profile for a classic distance runner should give the classic bell shaped curve.
3. A high dosage index generally indicates a horse better suited to sprints.
   

Related Features:

• Chefs-de-race from Dr. Steve Roman's website. This list is required to calculate dosage.
• Pedigree Query from Albin Warth. Lets you look up 4 generation pedigrees for many horses and calculates the dosage for them.
• Brief review of dosage also from Dr. Roman
• Dosage in a Nutshell another excellent explaination from Thoroughbred Champions
• Dosage Tool by Miles Michelson will do the calculations for you once you have the Chef-de-race figures.