Download Genetics III

Three Bars Genetics
American Quarter Horse Hall of
Fame & Museum
Three Bars
Bulldog Horse
Result
“Middle of the Road Quarter
Horses”
• Bulldog Quarter horses were known to be quick,
good on their feet, and to have incredible cow
sense.
• Against other breeds, (ex. Thoroughbred), they
were short distance runners that lacked some
racing ability.
• Bulldog horses were short, heavy, bulky,
muscular horses.
Three Bars
Adding Three Bars genetics to the Bulldog type
horses resulted in speedy race horses who were
no competition on the short distance quarter of a
mile tracks.
These sprinters had a longer neck, smoother
muscle tone, and heads which were much
cleaner and prettier.
Three Bars helped produce the racing quarter
horses which we are all familiar with today.
Though highly known for their athletic ability in the
rodeo arena, on the ranch, and other various
cattle events, quarter horses became even more
versatile by increasing their ability to sprint down
the tracks.
Bulldog Quarter Horses
However, the thoroughbred Three Bars can not
take all of the credit for this new style of quarter
horses. The Bulldog quarter horses brought just
as much to the table.
By crossing Three Bars with the Bulldog horses, it
gave these horses a better, calmer
temperament, more muscle, and cow sense
which is an advantage after retiring from the
tracks.
The combination of the long distance runners and
the bulldog sprinters made these horses
perfectly unbeatable.
As with most things, when you add an ingredient to
a mixture, it changes.
Many families, and breeds, can be influenced by
different factors, Three Bars is only one example
of what has changed the American Quarter
Horse breed.
The make up of each breed is different and when
you combine the genetics of two breeds you will
see certain characteristics change.
GENES are the smallest unit of an organism that
is still able to contain and transfer genetic
information.
GENETIC MATERIAL consists of DNA.
DNA stands for Deoxyribonucleic Acid. DNA
stores genetic information and tells the cell what
to do and how to do it. This determines what
traits you will have. DNA is what makes you
unique from everyone else.
Some genes are DOMINANT and some genes are
RECESSIVE.
For example, If you have a Tall parent and a Short
parent you have a chance of being either short
or tall, however since Tall is
the dominant gene it
gives you a GREATER
chance of being tall.
How do we determine the chances
of which genes we will receive?
The Punnett square is a diagram that is
used to predict the outcome of a particular
cross or breeding experiment. It is named
after Reginald C. Punnett, who devised
the approach, and is used by biologists to
determine the probability of an offspring
having a particular genotype. Wikipedia
Dad
y
x
x
x
x
x
girl
y
boy
Mom
x
x
x
girl
2:2
x
y
boy
50% chance to be a boy
50% chance to be a girl
Dominant genes are usually shown by using
a capital letter and recessive genes are
usually shown by using a lower case letter.
Aa
A is the dominant gene
and
a is the recessive gene
Remember, when there is a dominant gene,
this is the trait which shows up.
For example: For Tall we will use the letter “T”
We have two parents
Tt and tt
The first parent is Tall and the second parent is Short.
When you cross them it looks like this:
Parent 2
t
t
3:1
T
Tt
Tall
Tt
Tall
Parent 1
t
Tt
tt
Tall
Short
This gives you
A 75% chance
The offspring will
Be tall and a 25%
Chance the offspring
Will be short