The Rasmussen Factor
Apr 27, 2023 3:41:00 GMT -5
Post by mysaladdays on Apr 27, 2023 3:41:00 GMT -5
I thought this would be a fun topic for posting and/or discussion. Longshot's post about large heart factor got me thinking about this, as there does seem to be some overlap.
For those wondering what that is The Rasmussen Factor. The concept of inbreeding to superior females. Named in honor of Leon Rasmussen, the pedigree expert who wrote the “Bloodlines” column for DRF ( 1950-1987 retirement) his "Bloodlines" column was a staple for anyone interested in pedigrees and how they affected racing performance.
As far as I know, only about 2-6% of all thoroughbreds have this. It occurs when a horse can trace it's genetics to a common superior matriarch through different individuals, i.e. full or half siblings, within five generations (5x5 or closer). For instance, a well-known superior matriarch would be Aspidistra, dam of Dr. Fager and Ta Wee.
Rachel Alexandra was an RF. Quiet American, Unbridled, . And Danehill was a very well known RF. MAKYBE DIVA, WINX, FRANKEL, Nearctic are all RFs. Too many to name.
I am one who believes that the female side of a pedigree has a lot more influence in classic distance races than the sire side, and I followed Bill Lathrop's Modern Conduit Mares when he was still publishing and posting on websites. (He created profiles for the female side of the pedigree, similar to how Steve Roman did for the sire side.) I am only a fledgling and don't have his book, now out of print, so I haven't kept up with the conduits and any newly named ones. (It doesn't do a lot of good to know the profiles and triads unless you understand the system a little bit though.)
From DRF:
www.drf.com/news/lasting-pedigree-influence
"Rasmussen was a proponent of the early work of Dr. Franco Varola's Dosage system, which modified the original version of the Dosage theory introduced by Col. J.J. Vuilliers early in the 19th century. Rasmussen was closely aligned with the current theory of Dosage because he introduced Steven Roman's series of articles on the subject in his "Bloodlines" column in 1981. Within one year, however, Rasmussen became disenchanted with this modern form of Dosage, and went back to the topic he truly believed in most: inbreeding to superior females, which resulted in the highest likelihood of producing a quality Thoroughbred.
Rasmussen did not originate the theory of inbreeding to superior females. The great breeders of the 20th century, such as Federico Tesio, Marcel Boussac, and Abram Hewitt, all advocated this selective pattern of inbreeding. But no one observed and wrote about it as much as Rasmussen, who recognized the monumental value of such inbreeding.
In 1994, Jack Werk, editor and publisher of Owner-Breeder magazine, named this form of inbreeding the "Rasmussen Factor," or "RF," mainly in an effort to eliminate the need of repeating the explanatory phrase, "inbreeding to superior female families through different individuals."
Rasmussen joined forces with pedigree scholar Rommy Faversham to publish the definitive book on this specific type of inbreeding. "Inbreeding to Superior Females" (Australian Bloodhorse Review, Sydney, Australia, 1999) was a painstaking labor of love for both Faversham and Rasmussen and was an unqualified success in Europe and Australia, where the RF is considered the most critical element in a pedigree."
So who are the RFs in the Derby this year? If it matters to you at all, a friend did the research and there appears to be only 3:
There are only 3. Continuar, Raise Cain, and Forte.
If you're at all interested in breeding theories, and/or believe they have any influence on racing ability, then you can cross this with Longshot's post in the "16 Days Until The Derby" topic in the Triple Crown topic area. There does seem to be some overlap betweeen large heart theory and Rasmussen Factor.
Again, these are all more breeding theories than racing theories, but you will often find some of the higher class horses have 1 or 2 of these "factors".
For those wondering what that is The Rasmussen Factor. The concept of inbreeding to superior females. Named in honor of Leon Rasmussen, the pedigree expert who wrote the “Bloodlines” column for DRF ( 1950-1987 retirement) his "Bloodlines" column was a staple for anyone interested in pedigrees and how they affected racing performance.
As far as I know, only about 2-6% of all thoroughbreds have this. It occurs when a horse can trace it's genetics to a common superior matriarch through different individuals, i.e. full or half siblings, within five generations (5x5 or closer). For instance, a well-known superior matriarch would be Aspidistra, dam of Dr. Fager and Ta Wee.
Rachel Alexandra was an RF. Quiet American, Unbridled, . And Danehill was a very well known RF. MAKYBE DIVA, WINX, FRANKEL, Nearctic are all RFs. Too many to name.
I am one who believes that the female side of a pedigree has a lot more influence in classic distance races than the sire side, and I followed Bill Lathrop's Modern Conduit Mares when he was still publishing and posting on websites. (He created profiles for the female side of the pedigree, similar to how Steve Roman did for the sire side.) I am only a fledgling and don't have his book, now out of print, so I haven't kept up with the conduits and any newly named ones. (It doesn't do a lot of good to know the profiles and triads unless you understand the system a little bit though.)
From DRF:
www.drf.com/news/lasting-pedigree-influence
"Rasmussen was a proponent of the early work of Dr. Franco Varola's Dosage system, which modified the original version of the Dosage theory introduced by Col. J.J. Vuilliers early in the 19th century. Rasmussen was closely aligned with the current theory of Dosage because he introduced Steven Roman's series of articles on the subject in his "Bloodlines" column in 1981. Within one year, however, Rasmussen became disenchanted with this modern form of Dosage, and went back to the topic he truly believed in most: inbreeding to superior females, which resulted in the highest likelihood of producing a quality Thoroughbred.
Rasmussen did not originate the theory of inbreeding to superior females. The great breeders of the 20th century, such as Federico Tesio, Marcel Boussac, and Abram Hewitt, all advocated this selective pattern of inbreeding. But no one observed and wrote about it as much as Rasmussen, who recognized the monumental value of such inbreeding.
In 1994, Jack Werk, editor and publisher of Owner-Breeder magazine, named this form of inbreeding the "Rasmussen Factor," or "RF," mainly in an effort to eliminate the need of repeating the explanatory phrase, "inbreeding to superior female families through different individuals."
Rasmussen joined forces with pedigree scholar Rommy Faversham to publish the definitive book on this specific type of inbreeding. "Inbreeding to Superior Females" (Australian Bloodhorse Review, Sydney, Australia, 1999) was a painstaking labor of love for both Faversham and Rasmussen and was an unqualified success in Europe and Australia, where the RF is considered the most critical element in a pedigree."
So who are the RFs in the Derby this year? If it matters to you at all, a friend did the research and there appears to be only 3:
There are only 3. Continuar, Raise Cain, and Forte.
If you're at all interested in breeding theories, and/or believe they have any influence on racing ability, then you can cross this with Longshot's post in the "16 Days Until The Derby" topic in the Triple Crown topic area. There does seem to be some overlap betweeen large heart theory and Rasmussen Factor.
Again, these are all more breeding theories than racing theories, but you will often find some of the higher class horses have 1 or 2 of these "factors".