Sire Improving Foal by x%

[ragsdaj]

in advertising a stallion I sometimes come across a claim that the sire improves mare progeny by 25%, 40%. I read another where the sire improves the mare's foal better than any others in an area.

What are the statistics being used to make these claims? Just curious.

[austique]

Probably AEI and CI.

[ragsdaj]

the regional sire does say in their ad by AEI now that you mention it.

[bcassidy]

It usually shows up (eventually anyway) when you compare the AEI to the CL. The problem is that these numbers lag a stallions breeding career rather substantially (by I would guess two years at least) and small crop stallions can easily be skewed with a single high earning individual. Tread lightly with these statistics especially on young stallions but eventually, I think they are very good indicators on the ability of a stallion to improve a mare, it is just by the time they are accurate many years have gone by and if he is a good one, his stud fee usually goes through the roof. So in my opinion, by the time his numbers get accurate, we already know he is a good stallion. They are very little help early in their breeding careers.

[ragsdaj]

with all these statistics its not just looking at the numbers, it breaking them down to see if they really mean something.

thanks

[louis finochio]

If you have Stalliion A that has a AEI of 2.45 and a CI of 1.58 you would breed your mare to Stallion A.

Stallion A progeny made a total of 1276 starts divided by 125 starters=10 lifetime starts.

Stallion B has a AEI of 1.75 and CI 1.98.

Stallion B progeny made a total of 1497 starts divided by 92 starters=16 lifetime starts.

Would you breed your mare to Stallion A or B?

[bcassidy]

Louis Finochio--I would never use the AEI/Cl statistics as a primary source of data for selecting stallions so I cannot answer your question. One way I do use the number is to judge the book of mares that stallion is covering, anything over 2.0 for a CL and I will look at his progeny different than I would a stallion with a CL below 1.50. When that CL climbs, I believe the book of mares has as much to do with any success that stallion enjoys as much as he does. A lot of stallions would do quite well if they saw that kind of book. The CL is much less sensitive to time while the AEI is very much a function the precocity of that stallion's foals. Stallions with Late maturing foals get killed with these statistics--look at Arch. As always with any statistics----the devil is in the details.

[louis finochio]

To BC: I always look at the superior or inferior BMS that are bred to these stalliions that attain those lofty AEI -- CI numbers.

Lets use Benchmark as an example, Benchmark was bred to many mares by Vernon Castle, Man from Eldorado, and Pirates Bounty.

Benchmark out bred those mares by leaps and bounds. If Benchmark had the book of mares that AP Indy was bred to, their would be a prolific amount of Brother Derek's produced.

Many times a stallion's lofty AEI & CI is a fantasy figure, as those inferior mares are not producing the goods to push those stalliions over the top.

[zinn21]

Louis, Ive heard that before but have also read stallions who started their careers with avereage mares then went on to Ky. to cover superior mares and did little with them. It would be interesting to compare Fleet Nasrullah and Mr. Prospector's California and Florida books/progeny and see how much improvement took place when both moved to quality mares in Ky.

[louis finochio]

Fleet Nasrullah did not come up to expectations when he was bred to those better mares in Ky.

Mr. P went on to greater heights when moved from Fla. to Ky.

What causes a stallion's offspring to regress when bred to a better class of mare is a nightmare for us TB breeders.

Two and two does not always add up to four in the breeding shed, as their are many mysteries yet to be found.

[ragsdaj]

it does make for interesting conversation though not quite as good as discussing religion and politics. Fortunately pedigrees actually provides some benefit (the discussing of that is)