View Full Version : Coefficient of Inbreeding Percentage
Alcyone
01-03-2021, 03:27 PM
Just curious how many breeders refer to the Coefficient of Inbreeding Percentage when selecting a stallion for their mare?
The trends when it comes to top performing standardbred pacing horses are staggering.
I'm interested to discuss this topic.
Messenger
01-03-2021, 06:24 PM
I am not a breeder but I like to pretend :D
I enter mares into my Pedigree Partner db (PP) and do a Stallion Finder search for them
PP then ranks matches for them by Line Breeding Index (LBI) but the table also gives their FIB and SB%
see attached for an edited version of what all these terms mean
Pedigree Partner is/was Simon Morris's baby (who has always be part of the ClassicFamilies team)
I gather there are different Coefficients of Inbreeding as Pedigree Partner defines
Wrights where duplications must be common to both sire and dam while
Hardimans considers all duplications
Googling Coefficient of Inbreeding produces a wealth of links including this one from the Institute of Canine Biology where they seem to see use it to avoid detrimental inbreeding
https://www.instituteofcaninebiology.org/blog/coi-faqs-understanding-the-coefficient-of-inbreeding
Alcyone
01-03-2021, 08:44 PM
I've been working off allbreedpedigree.com, it uses 8 Generations for the COI percentage based on WRIGHT’s INBREEDING COEFFICIENT.
To give yourself the best chance of racetrack success I believe you need a COI of 5% or more. There are some outliers, however the success of horses in the range of 5-10% is too big to ignore.
My theory has been to match up sires and/or broodmares in the 3rd/4th generations and the results of horses with a COI of 5%-10% now adds a new level to ensure you select the correct stallion for your broodmare.
I would also suggest anyone heading to the Yearling Sales calculates the COI on any potential purchases.
Adaptor
01-03-2021, 09:35 PM
Ive been using the Norwegian Blodbanken.nu. for trotters for some years.
You can use it for 3,4,5,6,7 or 8 generations
I'm not sure which INBREEDING COEFFICIENT is used. Can anyone help please?
Here's Ready Cash
http://www.blodbanken.nu:8080/servlet/GetBBData?type=pedigree&breed=warm&trotter=5115236&showdepth=8
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