German Shorthaired Pointer
This is inbreeding (homozygosity) measured directly from DNA. The green line is at 6%, the average inbreeding of a litter produced by first cousins. Yellow (12%) is the inbreeding produced by half-siblings, and red (25%) is the average inbreeding produced by a sib-sib cross. (These are predicted averages; puppies in the litter can vary a lot above and below this just depending on what genes they happen to inherit).
German Shorthairs are much better off than most breeds. For perspective, commercial breeders of other domestic animals (eg livestock) keep inbreeding less than 10% because above this their profit drops off because of lower production, poorer health, etc, the usual consequences of inbreeding depression. The "sweet spot" for balancing benefits of inbreeding (more consistency, prepotence) with the costs (lower fertility, smaller litters and higher pup mortality, reduced lifespan, more genetic disorders, etc) is at about 5%. Above 10% the health of the animals declines. The only dog breeds below about 10% are "new" breeds (i.e., just entered AKC and haven't yet tossed out all the genetic diversity through selective breeding), breeds that are importing new animals (e.g., Tibetan mastiff), breeds with a huge base beyond show breeders (Jack Russell, Chihuahua).
I don't know what population of animals this represents (bench? pets? field?).
German Shorthairs are much better off than most breeds. For perspective, commercial breeders of other domestic animals (eg livestock) keep inbreeding less than 10% because above this their profit drops off because of lower production, poorer health, etc, the usual consequences of inbreeding depression. The "sweet spot" for balancing benefits of inbreeding (more consistency, prepotence) with the costs (lower fertility, smaller litters and higher pup mortality, reduced lifespan, more genetic disorders, etc) is at about 5%. Above 10% the health of the animals declines. The only dog breeds below about 10% are "new" breeds (i.e., just entered AKC and haven't yet tossed out all the genetic diversity through selective breeding), breeds that are importing new animals (e.g., Tibetan mastiff), breeds with a huge base beyond show breeders (Jack Russell, Chihuahua).
I don't know what population of animals this represents (bench? pets? field?).
This a scan of "runs of homozygosity" (ROH) that allows you to see where on the chromosomes there are large blocks of inbreeding. (There is info about how to interpret these plots HERE.)
The first panel is ROH for large blocks (5000 kb) of homozygosity. These represent "recent" inbreeding (i.e., last 6 or 8 generations). On page 2 of the tutorial, there are 3 panels per breed - at 70kb, 1,000kb, and 5,000kb; so this panel is comparable to the third one in each set. Again, you will see that Shorthairs are in better shape than most breeds, but definitely more inbreeding than randomly bred dogs (village dog and mixed breeds).
This panel is scans for 70kb blocks (the first panel in the sets of three in the tutorial). This shows both recent and ancient (hundreds of generations, so before breed formation) inbreeding.
This panel is a blowup of parts of chromosomes 5, 6, and 7. Here you can see that some dogs have blocks of homozygosity in the same place. For instance, the first dog has a large block in the middle of chromosome 6 that overlaps with a block of the 4th dog from the bottom. If these blocks were for genes important to breed type and the genes being selected for were recessive, you would expect all of the dogs to be homozygous there, but they aren't. So if you were making a breeding decision, pairing the first dog with others with blocks in the same place could be avoided.
