Rasmussen Factor (another study)


The following study is based on an evaluation of all horses sold at public auction in North America in 1999.  14,000+ weanlings, yearlings, or 2-year-olds were sold at public auction in North America in 1999.  Of these  8,309 sold for $10,000 or more. This is the population used in this study undertaken by David Dink and I have permission to use the data for this case study. 

RF qualifiers are defined to be inbred through both sire and dam to a “superior” female within five generations). The definition of “superior” used by Mr Dink is a mare who was a stakes winner herself or who produced one ore more stakes winners.   Only 3 mares being inbred to did not qualify using the above definition of "superior" and these are Mixed Marriage (reine de course) ,  Bebop II (stakes placed and producer of a number of stakes placed horses) and Princesse Commene (half sister to a number of stakes winners and producer of a stakes placed foal).  To simplify matters I have included these 3 mares into my definition of superior.


Table 1 : this table shows the 29 stakes winners who are RF qualifiers as set out above.

Name Age/Cost Pts* Inbred to Breeding
Rebound  T15,500 1 5x5 Imperatrice American Chance--Chugger, Drone
Six Hitter  W72,000 1 4x4 Natalma Boundary-Granny Kelly, Irish River
Minardi Y1,650,000 8 5x5 Knight's Daughter Boundary-Yarn, Mr. Prospector
Corporate Shuffle Y30,000 6 5x5 Almahmoud Diablo--Miss Applause, Fappiano
Ima Diablo T15,000 1 5x5 Almahmoud Diablo--Amads Queen, Minshaanshu Amad
Amber's Way Y125,000 1 5x5 Somethingroyal Forest Wildcat--Simply Saucy, Lord Avie
Go for Cat Y17,000 2 4x4 Flower Bowl Go for Gin--Nubbins, Storm Cat
Mugharreb  Y550,000 1 4x5 Somethingroyal Gone West--Marling, Lomond
Queen Carson Y200,000 1 5x3 Somethingroyal Lord Carson--Kind Reception, Secretariat
Mountain Girl T130,000 1 5x5 Flower Bowl Mountain Cat--Cherokee Crossing, Cherokee Colony
Creativity Y60,000 1 5x4 Gay Hostess Notebook-She's Realistic, In Reality
Meshaheer  W425,000 3 4x5 Almahmoud Nureyev--Race the Wild Wind, Sunny's Halo
Satan's Code Y185,000 3 5x5 Almahmoud Polish Numbers--Dancing Devlette, Devil's Bag
Rochelle's Terms T82,000 2 3x4 Shenanigans Private Terms--Make Yourself Go, Track Barron
Rahy's Secret  Y90,000 1 5x5 Almahmoud Rahy--Secret Advice, Secreto
Classical Romance Y32,776 1 5x4 Almahmoud Regal Classic--Halo's Romance, Halo
Glorious Grace Y95,000 1 3x5 Cosmah Saint Ballado--Class With Luck, Caveat
Lindsay Jean   Y120,000 6 4x5 Almahmoud Saint Ballado--Colony Bay, Pleasant Colony
I Love Silver Y52,000  1 5x5 Grey Flight Silver Ghost--Lost Love, Lost Code
Caught Out   Y150,000 3 4x3 Smartaire Smart Strike--Azhaar, Nijinsky II
Sabre Dance   T75,000 1 4x3 Thong Sword Dance--Sister of Darkness, Geiger Counter
Tee Cat Y90,000  1 5x5 Key Bridge Tabasco Cat--Chardae, Forty Niner
Hello Josephine Y27,000 1 4x4 Pocahontas Take Me Out--Silver Judy, Silver Series
Megantic Y275,000 1 4x4 Pange Theatrical--Jade Flush, Jade Hunter
Sunny Appeal   T95,000 1 4x5 Up the Hill Valid Appeal--Sunny's Sidekick, Sunny's Halo
Western Delight  Y55,000 2 5x5 Somethingroyal West by West--Far to Fly, U. S. Flag
Chamul   Y20,804 1 4x3 Gold Digger Mutakddim--Gold Liaka, Yukon
Getusumoney  Y25,500 1 5x4 Barra Mister Slippers--Day Off, Far Out East
Hattiesburg Y20,000 4x4 Broadway Mutakddim--Reason to Act, Bold Reason


 Of the 8,309 horses sold 508 went on to be stakes winners (by SITA, black-type rules). 

29 in Table1 above and the remainder in Table 6.


The following table  shows a breakdown of how the the sold horses have faired. 


Table 2: Foals Sold for $10,000 or more in North America in 1999
  No. Sold Stakes
All 8,309  508 6.11
RF Qualifiers 559 29 5.19
All Others (Not RF) 7,750 479 6.18

Those bred without have outperformed (in percentage terms) those with the Rasmussen factor.

The table above does not take into account the number of races won and it is conceivable that the 29 qualifiers won better races and more often than the non qualifiers.  

To try and quantify how good the races won were and how often they were won a 4-3-2-1 rule has been deployed.  i.e. 4 points awarded for each Gr1 win, 3 points for each Gr2, 2 points for a Gr3 and 1 point for a non group/graded stakes race.  The 29 RF stakes winners accumulated 59 points (see Pts column in table 1 above). For example Minardi has 8 points because he won 2 Gr1 races.

Table 3: Foals Sold for $10,000 or more in North America in 1999
  No. Sold Stakes Winners     %  Stakes Races
Won (4-3-2-1)
All 8,309  508   6.11


RF Qualifiers 559 29  5.19


All Others (Not RF) 7,750 479 6.18




So those stakes 508 winners gathered 1,615 points in total at an average of 3.18 per horse.  The RF qualifiers did significantly worse than average with just 2.03 points per horse. 


 Another aspect that needs to be looked at is the price of the foals.                                                       


Table 4: Sales Average and Median Prices  
  No. Sold Gross  Average Median
All 8,309 $669,963,780 $ 80,631 $33,000
RF Qualifiers Sold 559 $ 47,912,532  $ 85,711 $34,897


The sales price of  RF qualifiers is slightly more than the non-qualifiers.


 So what about the sales price of those that went on to be stakes winners?


Table 5: Sales Average and Median Prices of subsequent stakes winners 
  No. Sold Gross  Average Median
All 508 $ 70,110,441 $138,013 $50,000
RF Qualifiers 29 $  4,779,580 $164,813  $82,000
Non RF Qualifiers 479 $65,330,861 $136,390 $50,000


My conclusion would be that this study demonstrates that, in this particular instance, you would have to pay more to buy a horse inbred to a superior mare and win less! 


Using different approaches I have done studies that suggest that deploying RF in a mating is likely to be more successful than not doing so.  Even so, I have concluded that I am not sure that it is the process of inbreeding to a superior mare that is working because more often than not I find the mares back in the 4th generation are often behind top class stallions like Northern Dancer, Mr Prospector, Halo etc etc.


As well as the data above mention was made of different studies undertaken and this made me think about the percentage of foals inbred using RF.   A figure of 4% is often quoted has being the the percentage of breedings made that incorporate a RF inbreeding.   This percentage, whilst maybe correct at one point in time, cannot be used in a static sense and I think it probable that it should be treated as perhaps the lowest percentage of these breedings found.  The last sample I did was with foals 40000+ foals born 1998 through 2001 and I concluded that nearly 9.4% of foals were inbred using a RF with just 5 mares accounting for 60% all all such inbreedings and two, Natalma and Almahmoud, accounting for 30% on their own.   Mr Dink's data above has those inbred using RF at 559 /  8309  = 6.73%. 


This percentage of animals inbred using RF I think is very important.  As well as this study Mr Dink also related that in 1995-97 study the % inbred was 5.81%.  Even more importantly, albeit using a small sample, in a 1970-1974 sample the % was found to be a staggering 15.33%.  In 1980-84 using another small sample this has decreased to 9.15%.  So not exactly a static 4% of inbreedings are RF one's.


Mr Dink remarked that although the 1970-74 sample result seemed very high one has to understand the chronology of pedigrees in that most of those duplications involved Plucky Liege (Sir Gallahad III, Bull Dog, et al.), Selene (Hyperion, Pharamond, Sickle, et al.), or to a lesser extent some combination of Nasrullah, Royal Charger, and/or Mahmoud. 


Is the RF % rising again?  I have no doubt it is and again through very few sources.  Understand how we find instances of mares like Natalma, Almahmoud, Somethingroyal, Lalun etc and the reason why the % is rising should be pretty obvious. 


This rise and fall is worth considering.   In a couple of generations do we see another fall and then another rise as  inbreedings to the likes of Razyana (dam of Danehill) or similiar become almost unavoidable.


The 29 RF qualifiers who won stakes races were produced in table 1 above.   Other tables available are:


Table 6 which is a list of all 479 non-RF qualifiers who won stakes races can be found here.


Table 7 is a list of the RF qualifiers that did not win a black type race and can be found here.