So I am a huge pedigree geek. I admit it. I have software, and a decent database.
One evening I sat down and tracked the male and female tail lines all the way to the unregistered dogs. This mean take the top row of your pedigree (sire, g-sire, etc.) all the way to the end; or the bottom row (dam, g-dam, etc.).
Marque: Male tail: 23 generations, looks like this:
Ch. Foxglove Ashburton Bottoms Up ROM 8/97
Can Ch. Bonnyville Fairfax Nighthawk ROM
Ch. Alfenloch Whirlwind ROM 6/28/1987
Ch. Alfenloch Ryan O'Neil ROM 5/21/1985
Ch. Sunnybrook's Heritage Spirit ROM 9/29/1979
Ch. Sunnybrook's Matchmaker ROM
Ch. Romayne's Sportin' Life ROM 7/28/1974
Fair Play of Sea Isle ROM 3/8/1963
Ch. Malpsh The Duke Of Erle
Ch. Sea Isle Serenade ROM
Ch. Nashcrest Golden Note ROM CC 1/21/1951
Ch. Prince George O'Page's Hill ROM
Ch. Kalandar Prince O'Page's Hill
Ch. Mowgli ROM 4/2/1931
Ch. Wee Laird O'Downfield
Eng Ch. Blaeberry of Clerwood
Chestnut Lucky Boy
Chestnut Rainbow
Irvine Ronnie
Berryden Prince
Ashbank Olla
Nesting Topper
Frisky (unreg.)
Inbreeding coefficients are even more fun. I can be up to the wee hours playing.