Canadian Livestock Records Corporation
2417 Holly Lane, Ottawa, Ontario, Canada K1V 0M7
Tel: (Toll Free) 1-877-833-7110 or 613-731-7110 / Fax: 613-731-0704




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Canadian Livestock Records Corporation

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Bienvenue au site web de la SCEA

Inbreeding Coefficient (IC) Interpretation

(March 12, 2015) For the last two years, CLRC has been publishing Inbreeding Coefficients on our website for most breeds.  At the same time, we added a virtual mating option for every animal that includes an IC calculator.

While that additional information is available, it is the member`s responsibility to determine whether the coefficient is useful in making breeding decisions.  There are many sources of information on this subject available on the Internet. 

CLRC cannot provide specific advice on this matter, however, we can give you some idea of how coefficients relate to some easy to understand relationships. This will then give you an idea of how to interpret IC values for your animals in relation to these situations.


Inbreeding Coefficient (%) *

Animal bred to its own parent.
(eg. A son bred to its dam)


Half siblings bred to each other.
(eg. A common sire or dam)


Full siblings bred to each other.
(eg. Both sires and both dams are the same)


Animal has a single common great grandparent on both the sire side and dam side of the pedigree


(*) – This is the minimum Inbreeding Coefficient.  If there is further inbreeding in the pedigree, the coefficient will be higher.

IC values are not precise.  They depend on the number of generations of ancestry available and how many generations are analysed.  In general, the more generations of ancestry that are analysed, the higher and the more accurate the IC will be. 

In addition, IC values will vary between breeds depending on the breed history and the genetic diversity that exists within that breed.  If the genetic diversity is historically narrow (limited bloodlines were available), then IC values will tend to be higher for that breed.  This illustrates the importance of bringing in new blood lines occasionally (perhaps from other countries) when possible. 

CLRC`s virtual mating IC calculator does a 5 generation analysis by default.  In most cases, this gives a reasonable estimate of the coefficient.  There is also a 12 generation option which will give more accurate results but the response time for the calculation is noticeably slower.  Please be patient if you choose the 12 generation option. 

You should also be aware that when you recreate parent combinations for existing registered animals using the virtual mating IC calculator, you may not get the same IC value as posted on the website for the existing registered animal.  The IC value that we display for registered animals take into consideration the entire ancestry in the database, regardless of the number of generations available.  The displayed IC values will tend to be higher (and more accurate) than those provided by the virtual mating IC calculator.
Inbreeding Coefficients and Virtual Mating

(April 11, 2013) CLRC announces that Inbreeding Coefficients are now published on our website for all breeds except Swine. We hope to add Swine in the near future.

Inbreeding Coefficients measure the degree of repeating or common ancestors that exist in the pedigree. Coefficients are measured as a percentage from 0% to 100% or values from 0 to 1. Our website uses percentages. An animal with a coefficient of 0% has no known common ancestors that appear on both the sire and dam side of the pedigree. If you were to breed an animal to its sire or dam, the resulting offspring will have an inbreeding coefficient of at least 25%, depending on the number of other common ancestor lines that might appear in the pedigree.

In addition, CLRC now offers a virtual mating service which will determine the inbreeding coefficient for a proposed mating and display a five generation pedigree and common ancestor list. The virtual mating option appears at the bottom of each animal page and you can select a mate based on member ID number, animal name or registration number. If you select the ID number option, you can select one or more or all animals owned by that member.

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Canadian Livestock Records Corporation
2417 Holly Lane, Ottawa, Ontario, Canada K1V 0M7
Tel: (Toll Free) 1-877-833-7110 or 613-731-7110 / Fax: 613-731-0704 /
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