Certain sires in a pedigree may show up with letters in brackets after their year of birth. Fappiano is an example "[IC]". These letters signify the Fappiano is a chef-de-race horse and they are used to calculate the dosage numbers above the pedigree "DP = 14-12-12-0-0 (38) DI = 5.33 CD = 1.05".
The concept of Chef-de-Race (CdR) and dosage is a method used to predict the racing characteristics of a horse based on its pedigree. The system assigns specific points to influential sires (stallions) in a horse's lineage, categorized into different aptitudinal groups, to estimate the potential performance and optimal racing distances for the horse.
Chef-de-Race (CdR) and Dosage Profile
A Chef-de-Race is a stallion that has been identified as having a significant impact on the breed, specifically influencing certain traits desirable for racing. These sires are classified into different categories based on the type of influence they have on their offspring. The five numbers listed on the Dosage Profile (DP) of a horse are essentially points given in the following categories based on Chefs in its ancestry:
• Brilliant (B): Sires that contribute to early speed and precocity.
• Intermediate (I): Sires that contribute to middle-distance speed.
• Classic (C): Sires that contribute to stamina and the ability to perform well over classic distances (typically 1 1/4 miles).
• Solid (S): Sires that contribute to stamina and long-distance ability.
• Professional (P): Sires that contribute to extreme stamina, typically effective at long distances (2 miles and above).
Dosage Index (DI)
The Dosage Index (DI) is a numerical representation that quantifies a horse's potential aptitude for certain racing distances based on the CdR sires in its pedigree. It is calculated using the following steps:
Points are assigned to each CdR sire in the horse's pedigree up to the fourth generation. Each CdR sire contributes a fixed number of points based on its classification. Typically, these points are distributed as 16 points in the first generation, 8 in the second, 4 in the third, and 2 in the fourth.
The points for each category (Brilliant, Intermediate, Classic, Solid, Professional) are then summed for each category. A higher DI suggests a propensity for speed and shorter distances, while a lower DI indicates stamina and suitability for longer distances.
Center of Distribution (CD)
Another metric, the Center of Distribution (CD), further refines the horse's distance potential as a statistical indicator of how spread out the ratings are that were used to acheive the Index number. The CD value can help indicate whether the horse leans more towards sprinting (higher number) or distance racing (lower number).
Practical Use
Trainers, breeders, and handicappers use the dosage system to:
• Assess the likely racing aptitude of a horse based on its pedigree.
• Make breeding decisions to produce offspring with desired racing traits.
• Evaluate the potential performance of young or unproven horses in races of varying distances.
By analyzing the dosage and CdR influences, one can better predict the horse's strengths, whether it be speed for shorter races or stamina for longer races, thus optimizing training and racing strategies.
Chef-de-race horses on this site were designated by the now-retired Steve Roman and continued by Steve Miller and also ANZ for Australian Thoroughbreds.