The COI, or “coefficient of Inbreeding”, is a measure of the degree of “relatedness” in an individual. The COI tells us the percentage of common ancestry in an individual’s pedigree.
So, is it important? Yes and no.
Generally speaking, for most individuals that are breeding animals, keeping your COI on the lower end of the spectrum is a good place to start. The kunekune population in the world as we know it today, descended from just a handful of animals. In Canada in particular, the gene pool is even more restricted than in other parts of the world due to the stringent regulations surrounding the importation of animals from different countries.
What level of COI should I aim for?
For me as a breeder, genetic diversity is of the utmost importance so that I can meet the needs of various clients that come to me, whatever their goals may be. Under 10% COI is considered optimal, but up to 15% is still a good level. The difference between 10% and 15% is very minimal, and the conformation of the animal is ALWAYS more important than that 5% difference is! You still aren’t likely to see piglets born with additional limbs at this level lol
All joking aside, there are situations where you may see a much higher COI and it’s not necessarily something to be afraid of. Many experienced breeders are looking to produce a high level of uniformity in their herds, or are looking to amplify certain traits, and will turn to linebreeding. Linebreeding is the purposeful breeding of more closely related individuals, such as parent and offspring, half-siblings, nephew to aunt, etc. Linebreeding certainly has its place, but I think its better left to breeders with lots of experience under their belts. Although its true goal is to amplify positive traits, the reverse can also happen just as easily and can amplify negative traits. You should absolutely only breed the very best to the very best in these circumstances and be prepared to cull heavily if it doesn’t work out. There’s a running joke in among animal breeders – if it’s intentional, it’s linebreeding. If it’s accidental, it’s inbreeding! When you are looking to add to your herd, or plan your breedings if you have multiple animals, you can check the COI of the resulting animals using the “Trial Breeding” feature in the AKKPS herdbook. In summary, when you are new to breeding, aim for a COI of 10% or less between your breeding pairs, but don’t be scared away by a COI in the 10-15% range. In the big picture of what makes a suitable breeding animal or breeding pair, the COI is just one small piece of many.