BloodHorse revives Dosage Profiles with 23 new chefs, revised Unbridled's Song

BloodHorse has brought Dosage Profiles back into focus for North America, adding 23 new chefs-de-race and reclassifying Unbridled’s Song in a move that immediately updates how breeders and handicappers can frame speed, stamina and classic potential. Steve Roman returned to manage the system with Ken Kush after stepping away in 2016, restoring a tool that many horsemen still use when judging whether a prospect can carry its form to a mile and a quarter.

The overhaul matters because dosage is more than pedigree decoration. Roman’s framework breaks aptitude into five groups, Brilliant at +2.00, Intermediate at +1.00, Classic at 0.00, Solid at -1.00 and Professional at -2.00, with the Center of Distribution adding another layer to the distance picture. The system traces back to the early 20th century work of French officer Lt. Col. J. J. Vuillier, but Roman’s contemporary Dosage Index changed how Thoroughbreds are bred, bought and sold. In that model, a Kentucky Derby candidate with a Dosage Index above 4.00 has traditionally been viewed as a tougher classic proposition.

The new roster pushes modern bloodlines deeper into the chart. The 23 newly designated chefs are Munnings, In Excess, Speightstown, Rubiano, Into Mischief, Elusive Quality, More Than Ready, Candy Ride, Uncle Mo, Street Cry, Scat Daddy, Quality Road, Distorted Humor, Tiznow, Quiet American, Medaglia d'Oro, Curlin, Tapit, Kitten’s Joy, Dynaformer, Empire Maker, English Channel and Alleged. Roman and Kush said they used a threshold of at least three sons among the 150 leading sires, a filter designed to capture transmitted influence rather than nostalgia. That puts some of the most recognizable names in the current sire market, including Into Mischief, Curlin, Tapit and Uncle Mo, squarely inside the dosage conversation.

Unbridled’s Song’s move from Intermediate to Brilliant-Classic is the other notable shift, and it gives a longtime speed influence a new numerical shape inside the system. For classic season debates, that could matter in practical ways, especially for Derby trail horses, breeze-up prospects and stallion candidates being evaluated for whether they can stretch out or are more likely to peak at shorter trips. The update also shows dosage still has a role in an era dominated by data and speed figures: it keeps old-school pedigree analysis tied to the current market instead of letting the category go stale.