Dosage Adds 23 New 'Chefs-de-Race' for North America

Steve Roman has reinvigorated his Dosage Profiles for North American pedigrees with the assistance of dosage enthusiast Ken Kush. Together they have updated the profiles with 23 new "chefs-de-race." Under Roman's system, "chefs" are identified if their progeny excel above-and-beyond at a specific distance or distances. Stallions showing such prepotency are then assigned to one or two of five aptitudinal groups—Brilliant, Intermediate, Classic, Solid, or Professional. The Brilliant category represents pure speed, while the Professional end of the spectrum includes the hardiest stayers. Each of the five aptitudinal groups corresponds to a point along a scale: Brilliant (B) at +2.00, Intermediate (I) at +1.00, Classic (C) at 0.00, Solid (S) at -1.00, and Professional (P) at -2.00. A stallion's place on the scale identifies his Center of Distribution (CD), which is considered to be a more accurate measure of aptitudinal type. Roman stepped away from maintaining the dosage system in 2016 and turned the job over to Englishman Steve Miller, whose primary focus was on European breeding. Consequently, the North American sires that qualified as "chefs" have not been updated in several years. Now Miller has stepped away and Roman is back to update the system for American racing. Roman and Kush have identified 23 new "chefs" and amended the profile of one—Unbridled's Song, whose profile was changed from Intermediate to Brilliant-Classic. The new "chefs" and their aptitudinal influence are as follows: Munnings: Brilliant-Intermediate In Excess: Brilliant-Intermediate Speightstown: Brilliant-Intermediate Rubiano: Brilliant-Intermediate Into Mischief: Brilliant-Classic Elusive Quality: Brilliant-Classic More Than Ready: Brilliant-Classic Candy Ride (ARG): Brilliant-Classic Uncle Mo: Intermediate-Classic Street Cry: Intermediate-Classic Scat Daddy: Intermediate-Classic Quality Road: Intermediate-Classic Distorted Humor: Intermediate-Classic Tiznow: Intermediate-Classic Quiet American: Classic Medaglia d'Oro: Classic Curlin: Classic Tapit: Classic Kitten's Joy: Classic Dynaformer: Classic Empire Maker: Classic-Solid English Channel: Solid-Professional Alleged: Classic-Professional To identify the new chefs-de-race, Roman and Kush started with sires with at least three sons among the 150 leading sires on the general sire list, since a chef-de-race should display an ability to transmit his influence. Roman said that occasionally a chef-de-race may be identified solely on the basis that his runners' performance type dramatically contradicts their pedigree; however, this is not common and is not the case in the current update. The methodology involved collecting data on a candidate-sire's best runners—usually several dozen stakes winners—in order to obtain a representative sample. They emphasize stakes winners because their performance characteristics are more likely to reflect their true genetic potential. The average winning distance of stakes wins is then compared to the existing dosage figures to determine whether the distance-pedigree relationship conforms to the model. To illustrate, an analysis of 61 stakes winners by Tapit, encompassing 208 stakes wins, reveals an AWD of 8.67 furlongs and an average CD of 0.69. The present model predicts an average CD of 0.43 at that AWD, indicating that Tapit is transmitting more stamina to his runners than is currently reflected in his dosage figures. When Tapit is assigned as a Classic chef-de-race, the average CD drops to 0.45, just 0.02 CD units from the predicted value, bringing his sub-population almost perfectly into alignment with the general population. Roman, a research chemist by trade, developed his Dosage Profiles from concepts followed by Lt. Col. J. J. Vuillier and Dr. Franco Varola, who each had different systems for identifying small groups of common ancestors that were influencing the breed.