Great breeders from the past looked to breed quality stallions and mares from proven thoroughbred lines and it did not matter if the ancestor of that line was five, six, seven generations or more removed from the foal as long as the foal’s parents were quality thoroughbreds.
Hence, that is how Lt. Colonel Jean-Joseph Vuillier developed the dosage system in the 1920’s. He studied the pedigrees of hundreds of the best thoroughbreds at that time going back to the 12th generation and found that 15 proven stallions and one mare were prominent in the pedigrees of the horses he studied. Pocahontas was the only mare in his list. The fifteen stallions included: Pantaloon, Touchstone, Birdcatcher, Newminster, Hermit, Galopin, Bend Or, Voltaire, Gladiator, Bay Middleton, Melbourne, Stockwell, Hampton, Isonomy and, last but not least, the great St. Simon.
Vuillier then assigned a numerical figure for each of those key thoroughbreds and formulated a system to calculate dosage based upon the number of strains of those key thoroughbreds found in a foals pedigree going back 12 generations.
Italian Dr. Franco Varola later revised Vuillier’s dosage system adding 120 sires to the list and designating them “Chefs-de-race”.
Two of the most sought after bloodlines by many of the great breeders, especially Federico Tesio, were the lines of St. Simon and Stockwell. One of my all-time favorites, and perhaps the greatest thoroughbred ever, Ribot, was the product of that mating. Ribot’s sire Tenerani and his dam Romanella were champion thoroughbreds in Italy. Many of Ribot’s ancestors in the first five generations were also champions but the most important aspect for Tesio was that many of those thorougbreds were descendents of the proven sire line of St. Simon and Stockwell. Over half of the 32 ancestors in Ribot’s 5th generation are descendents of the sire line of Stockwell (11 strains) and St. Simon (7 strains).
Stockwell’s dam was the very influential Pocahontas. Pocahontas also produced the influential sires Rataplan who was a full brother to Stockwell and their half brother King Tom. If you study the pedigrees of Tesio’s champions you will often find a good mix of thoroughbreds who are descendants of St. Simon, Stockwell, Rataplan, King Tom and Pocahontas.
If you study the Classics as I have you will find that throughout the years there have been several sire lines that have had a major impact on the Classic races and usually that impact only lasts for about 10 or 12 years. Right now Northern Dancer and Mr. Prospector are the two dominant lines. How long will they continue to dominate? No one knows but as pedigree enthusiast, I’d love to find the next emerging line to dominate the Classics.