Raise A Native Broodmare Sire Line

[stancaris]

Here is an interesting question---- The Raise A Native Sire Line has accounted for 18 Kentucky Derby winners through history (the first one was Majestic Prince in 1969). How come the Raise A Native broodmare sire line has only accounted for 3 Ky Derby winners thru history: Barbaro, Mine That Bird, and Orb? The score is 18 to 3 in favor of the sire line.

A side note: Mr. Prospector, a Son of Raise A Native, led the Broodmare sire list a whopping 9 times and still could not be represented by more than 3 Ky Derby winners whereas his sire line generated 11 Ky Derby winners.

What genetic factors could have been a possible explanation for the above glaring differences?

[stancaris]

What I meant to say above was--how come Mr. Prospector could only get 3 Ky Derby winners from his broodmare sire line but generated 11 Ky Derby winners from his sire line.

[DDT]

Stan

The fact that Mr. Prospector himself only sired 1 Kentucky Derby winner and has never been the broodmare sire of a Kentucky Derby winner is the main genetic reason. The fact that you are talking about a race that is restricted by age and limited by a maximum of 20 starters based on earnings/points brings up the question of how many starters were sired by Mr. Prospector and how many starters had him as a broodmare sire. A better question is why do you think there is such a great difference between the sire line and the broodmare sire line.

DDT

[hpkingjr]

Without any empirical basis, just additional pooled ignorance, I would analyze this question on a more practical basis. As the RAN Sire lines took off most people avoided close inbreeding to mares that carried RAN or Mr. P. With time those giants have disappeared to the 4th, 5th and 6th generations and slowly the kinks were getting worked out by astute breeders. Mr. P. did not like, as a rule Mr. P. inbreeding, unless Fappiano was involved. A male to female inbreeding to Mr. P. generally was not productive thus many great Mr. P line mares got bred to other stallion lines, notably Northern Dancer.

With the success of the Stallion sons of RAN and Mr. P. it just happened by the sheer numbers. Since 10 RAN studs produced on average 1000 foals a year and 10 RAN mares produced on average 8 foals a year, maybe the females are stronger than you think.

I really do not have a valid answer to your question but it certainly is intriguing.

[Pan Zareta]

how come Mr. Prospector could only get 3 Ky Derby winners from his broodmare sire line but generated 11 Ky Derby winners from his sire line.

Because Mr. P.'s progeny were on avg. best at distances <10f and he was so successful a sire that an unusually high number of his sons entered stud at the top tier of the TB breeding population where males have far more opportunity to be bred to improve stamina than do females.