What COI Measures
The coefficient of inbreeding estimates the probability that two copies of a gene in an individual are identical by descent from a shared ancestor. A planned-litter COI estimates the relationship created by a proposed sire and dam.
Individual COI vs. Planned-Litter COI
An individual’s COI describes the mating that produced that pig. The planned-litter COI describes a new proposed mating. A low-COI pig can still produce a high-COI litter if paired with a close relative, and two higher-COI pigs may be unrelated to each other in ways a simple label does not reveal.
Always examine the actual proposed pedigree rather than relying on one number copied from a sale listing.
The AKKPS members area has a COI calculator to help plan a mating and calculate COI automatically.
Why Genetic Diversity Matters
Small breed populations can lose options when a few sires, farms, or family lines dominate. Diversity gives future breeders more ways to manage recessive risk, adapt to changing goals, and avoid repeated close relationships.
- Track repeated ancestors and popular sires.
- Retain multiple useful families rather than one fashionable branch.
- Exchange genetics deliberately instead of collecting unrelated pigs without goals.
- Measure function so diversity and quality advance together.
COI Cannot Tell You Everything
Pedigree COI depends on the depth and accuracy of the recorded pedigree. It does not directly measure every harmful variant, overall heterozygosity, structure, fertility, temperament, performance, or whether the shared ancestor carried desirable or undesirable traits.
Use DNA parentage, accurate registration, health information, functional evaluation, and offspring records alongside COI.
Using COI in a Responsible Pairing
- Verify identities and pedigree depth.
- Review the planned-litter COI and repeated ancestors.
- Ask why those ancestors are being repeated.
- Compare the parents’ actual strengths and faults.
- Consider future mates for retained offspring.
- Document the decision and measure the litter.
Continue with linebreeding versus outcrossing and reading the pedigree.
Return to The Complete Guide to Kunekune Genetics and Breeding
Frequently Asked Questions
What is a good COI for a Kunekune?
There is no universal number that replaces breed-organization rules, pedigree depth, population context, animal quality, and the purpose of the mating. Lower relationship generally preserves more options, but the whole pairing matters.
Does zero COI mean the pigs are unrelated?
It may mean no shared ancestors were found within the recorded pedigree depth. It does not prove the animals share no ancestry or genetic variants.
Can inbreeding expose recessive traits?
Greater relatedness can increase the chance that matching inherited variants meet in offspring, including harmful recessives.
Is outcrossing always safer?
No. An outcross may add diversity but can also introduce unknown faults or produce inconsistent results. Evaluate the actual animals and families.