How to read a pedigree — and calculate inbreeding
Five generations say more than five phone calls. Here is how to spot recurring individuals and what the percentage means.
A pedigree is not just a list of names. It is a record of what has already been tried in the breed — and the only map you have of where the genes come from.
Start from the back
Read the pedigree right to left rather than the other way round. That way you quickly see which individuals recur in several branches. If the same dog appears two or three times within five generations, it is worth pausing to think.
What the inbreeding coefficient actually measures
The inbreeding coefficient is the probability that a puppy receives two identical copies of the same gene from a common ancestor. It is usually calculated over five generations. A full-sibling mating gives 25 per cent, a cousin mating roughly 6.25 per cent.
Which number is good?
A common rule of thumb is to stay below 6.25 per cent over five generations, and considerably lower in small breeds where the whole population is already related. But the number must be read alongside health status and temperament — a low coefficient does not save a combination where both parents share the same problem.
Look at the whole population
In a small breed, two dogs can look unrelated over five generations and still be closely related over ten. If the breed is small it is worth looking further back, or looking at how much each individual male is used overall.
In short
A pedigree takes ten minutes to read and can save you years of trouble. In ProBreed, lineage and the calculated inbreeding coefficient sit in the same view as the health tests.
