The COI tells you how closely related a puppy's parents are, and why that matters for health.
The coefficient of inbreeding is the probability that the two copies of a gene a puppy inherits come from the same ancestor on both sides of the pedigree. A mating between unrelated dogs gives a low value; matings between close relatives give high values.
High inbreeding raises the risk that recessive disease genes meet, and is linked to smaller litters, weaker immune systems and shorter lives, known as inbreeding depression. Popular sires used many times also narrow the gene pool of the whole breed.
A COI depends on how many generations are included, so only compare values calculated the same way, preferably over many generations. Many kennel clubs and breed clubs give recommendations, often to stay below the breed average. The app's inbreeding calculator lets you test a planned mating before you decide.
Correct answer: The parents are closely related
A high coefficient of inbreeding means the parents share many ancestors.
Correct answer: Recessive disease genes meeting
Inbreeding raises the risk that recessive disease genes are inherited from both sides.
Correct answer: They depend on how many generations are included
The more generations included, the higher and more accurate the value; compare like with like.
Correct answer: They narrow the gene pool when used many times
Many litters by one male reduce the genetic diversity of the whole breed.
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