Basic Guide to Reading Pedigrees
This website offers complex pedigree reports and knowing how to read them
and understanding what everything means in a pedigree can really help you
out. If you scroll to the bottom of this page, you'll find the pedigree for
Kentucky Derby winner REAL QUIET. We'll be using this pedigree as an
example so you can follow along.
Inbreeding
Inbreeding occurs in a pedigree when the same horse appears twice through
different offspring. Real Quiet's pedigree has a fair amount of
inbreeding in it. The Pedigree Database will show inbred horses by placing
a colored bar to the right of names inside the pedigree. Notice in Real
Quiet's pedigree below that there are colored bars next to Dr. Fager,
Raise a Native, Cequillo, and Rough'n Tumble. The bars are color coded
so that you can quickly find matching sets of horses. All of these horses
appear more than once in the pedigree through different offspring, notice
that Aspidistra also appears more than once in the pedigree, yet she
doesn't have a colored bar next to her name. This is because she only
appears through her son Dr. Fager and no other horses.
Cross Duplicates
Inbred horses that appear in both the dam and sire side of the pedigree
are referred to as cross duplicates. In Real Quiet's pedigree, Raise a
Native appears twice, once in Quiet American's pedigree and once in Really
Blue's pedigree. Dr. Fager on the other hand only appears in Quiet
American's pedigree and thus he isn't a cross duplicate. On this site, you
can choose to highlight the cross duplicates in a pedigree or all of the
inbred horses. Why is this important? The reason it's important is that
inbreeding is only a factor when both the sire and dam have similar
ancestors and the subject horse can have matching sets of chromosomes
(alleles) from a specific ancestors.
Siblings
In thoroughbreds, there are three types of siblings that are generally
noted. Full siblings (full brothers/sisters that share the same sire &
dam). 3/4 siblings (horses that share 3 out of 4 grandparents). In Real
Quiet's pedigree, Dumure and Killaloe are 3/4 siblings sharing Rough'n
Tumble, Aspidistra, and Cequillo. Half siblings are those that either
share two grandparents or have the same dam. In Real Quiet's pedigree,
Quiet Charm and Grand Splendor share the same dam and are thus considered
half siblings. Note that horses that share the same sire are not generally
considered half siblings. In the pedigree database, the relationships will
be noted by color coded dotted, dashed, and solid lines below a horse's
name. A solid line will highlight full siblings, a dashed line (like the
green one below Demure's name) shows 3/4 siblings. Dotted lines like the
one below Quiet Charm show half siblings.
Grade I/Champion Horses
In the pedigree database, horses that have either won a grade I race or
the equivalent of a grade I race (before the grading system came out) are
always noted in bold text. Generally speaking, the more Grade I
winners/champions in a pedigree, the better bred a horse is, especially
when they show up in the dam's side of the pedigree. Note that most sires
today have had fairly succesful racing careers and are often Grade I
winners. It's not uncommon to see a good sire in a pedigree, but it's a
lot less common to find mares who have done well.
Racing Records/Earnings
Many horses in the database will show up with a career racing record
and
earnings next to their names. For instance Really Blue has the following
numbers under her name. "21-3-5-1 $31,920". This means that she raced 21
times in her career, won 3 races, finished second 5 times and third 1
time. During her career, she earned $31,920 in earnings. Horses that
haven't raced may show up with "Unraced" under their name.
Chefs and Dosage
Certain sires in a pedigree may show up with letters in brackets after
their year of birth. Fappiano is an example below "[IC]". These letters
signify the Fappiano is a chef-de-race horse and they are used to
calculate the dosage numbers above the pedigree "DP = 14-12-12-0-0 (38)
DI = 5.33 CD = 1.05". Chef-de-race horses on this site are designated by
Steve Roman and more information about dosage and how to use it as a
breeding tool can be found at http://www.chef-de-race.com/.
Genetic Strength Values (GSV)
Genetic Strength Values are another system to evaluated a horse's
pedigree
and try to quantify the pedigree. Below Believe It's name, you'll see a
number in braces "(54.30)", this is Believe It's Grasp Rating. Above the
pedigree, you'll see the GSV number "GSV = 71.10". GSV ratings and Grasp
numbers were developed by George
William Smith and you can find out more
information about using these numbers at his Understanding
the GSV page.
Reines De Course
Ellen Parker is a pedigree researcher who has spent lots of time studying
famous mares. She's comes out with a list of the 500 or so most
influential mares of the last century. These Reine De Course (Queens of
The Turf) mares are highlighted in the pedigree with a green star. For
instance Gay Hostess is a Reine De Course mare. If you are serious about
pedigrees, check out her
site for some good articles and also some great books about famous
broodmares.
Photos & Information
We have photos and extra information for a great number of horses in the
database. These will be noted in the pedigree with small icons (
). The pedigree below
isn't a working pedigree, but on the site, you can run your mouse over
these icons to get photos or additional information for the horse in
question.
Tail Female and Family Numbers
The Tail Female pedigree is one that goes from dam to dam. So Real Quiet's
Tail female pedigree includes Really Blue, Meadow Blue, Gay Hostess, Your
Hostess, Boudoir,... etc. On the right side of the pedigree, you'll notice
a column of numbers and letters that looks something like 5-f, 8-f, etc.
These are female family numbers and trace the tail female pedigrees back
to certain taproot mares. For more information on female family numbers,
we suggest you take a look at Elizabeth Ross's Bloodlines
site and also Thoroughbred
Heritage.