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Chest Profile
Chest Front View
Maximum Lung Expansion
It takes a maximum amount of room in the rib cage to give
a horse enough air to be a top performance horse.  
When looking at a horse for an athletic prospect look for
wide spaced ribs that extend out and back from the spine.
The ribs also serve to shield the heart, lungs and windpipe
and the ribcage's shape as a lot to do with the way the horse
is shaped and how much endurance it will have.   The ribs
should be curved and arch backward instead of straight down.
The horse's chest is oval in shape amd it is long from the
backbone to the breastbone and narrow from side to side.
The width of the breastbone help to determine the width of the
horse's front end and the space between the front legs.   The
area between the bottom of end of the neck and the tops of the
front legs is called the "chest" or the "breast."

A horse will have between 17 and 19 pairs of ribs depending
upon breed influence.   The more ribs the more depth in
flank.   When looking from the side the underline should
rise gradually toward the hindquarters and not end up narrow
or at a sharp angle at the flank.

The first few ribs are not visible under the hide as these are
underneath the shoulder blades. The first rib is shortest and
angles a little forward.   The next rib is nearly vertical.
The rest slope backward.   For a horse to be correct in
side profile it does not matter what breed it is.   What
matters is that the vertebra that carry the ribs should extend
back toward the pelvis and have no slack.   There should be
very little space between the last rib and the angle of the
hindquarter.  This makes the horse have a round barrel and
a short "loin" or short back.

Chest on the Side Profile
There are two types of suitable chest conformation.  Looking
at the chest from the side there is round, barrel chest and the
wide, deep chest.   You will see the round, barrel chest on
a lot of stock horse breeds and the deep wide chest on sporting
breeds.  The horse should appear to be wedged shaped
with the chest narrower at the front and wider at the rear.
This will make the body appear to streamlined and balanced.
The widest part of the rib cage should be behind the girth.
The barrel will appear to be wider behind a rider's leg than
before or at the girth.   The greatest rounded look will be toward
the back of the girth and this allows for a wide diaphragm.
This profile also allows for the most comforatable ride and for
the muscles of the shoulder, legs and neck to hold the saddle
in place right at the center of the back.   It is the ideal
conformation for the rider to stay in correct balance with the

Viewing the Ribs on a Side Profile
Look for depth and width in the rib cage on the side profile.
A major fault in rib cages is the "slab-sided" horse in where
flat ribs project straight down instead of back. The rib cage
then becomes long and narrow and the loin is long with a wide
area between the hip and the last rib.   The horse with well
sprung ribs will have a long deep underline and a shorter back
and loin.   This type of horse will have a much stronger back
and be able to manenever with ease.   The loin is the
muscular area behind where a saddle would sit.  It is where
the last rib is to the point of the croup, which is the highest
part of the rump.

Viewing the Slab Sided Horse
A horse with a short set of rear ribs has a very little depth
in the area of the flank.  The "flank" area is just ahead
of the sheath or udder and includes the lower line of the abdomen at the rear.   A horse that has these shallow flanks is
referred to as "herring-gutted". They look a little bit like a
greyhound dog.  Since these type of horses have less room
for air they often lack stamina.  To add to the equation the
flank generally has less abdominal muscle developement and
the loin is weaker so they cannot carry alot of weight.

Heart Girth
The total circumference of the horse or the area that encircles
the horse from just behind the front legs and the withers is
called the "heart girth."  To measure it correctly you will need a
tape measure.  Drop it over the withers and under his chest
just behind the elbows.  The tape should fit tight and vertical.
Take the measurement when the horse has exhaled and his
lungs are not expanded.   Start with a 14.2 hand tall horse and
the measurement should be at least 72 inches.   For every 1"
taller the heart girth should be at least 1" larger.  For
every inch greater the heart girth will increase the percentage of
space open for air intake.   The heart girth should always
be greater than the height of the horse.   Heart girth
measurements can also givea pretty accurate indiction of the
horse's weight.

The Side Profile of the Pectoral Muscle
When looking at the side profile the breast muscles should be
visible as a bulge in the front.   It should not be so large
as to be a mass that protrudes as in a "camped under" horse
(where the front legs end up postioned too far back.)


Viewing Chest from Side Profile
"X" shows ribs well extended making
the horse deep with the flank.
"Y" thru "Z" show the desired close coupling
or the space between the last rib and
the angle of the hindquarters
PS-ISH #512-P
Dappled Dun
Ideal Stock Horse Mold Manufactured by the Peter Stone Co.
Sculpted and painted by by Carol Williams
Rio Rondo Enterprises

Excellant example of a should be wedge-shaped.
Narrower in the front and wider behind.

The Front View of the Chest:
When viewed from the front the chest of the horse should be
well defined and not blend into the bottom of the neck.
The width of the chest is defined by the structure of the bone
beneath it.   The front of the chest is measured from
one side of the point of the shoulder to the other side of
the point of the shoulder.   A pair of large muscles in
the front called the pectoral muscles line up to form a "V"
at the top of and above the front legs.  The wider
the "V" the wider the width of the chest and the wider width
the legs will travel in parallel stride.  The chest is
not attached to the front legs but is instead suspended and
supported between the shoulder blades by muscles. Muscles that
are attached at the bottom of the rib cage also help to support
and suspend the chest from the sides of the forelegs.   This
aids in cushioning the concussion of the forelegs striking the ground
from the whole body.   It also keeps the heart and lungs from
being disturbed.  If the horse does not have adequate muscling
of the pectoral muscles there will be a flat space there instead
of the inverted "V".

Chest Shape From the Front:
When looking at the horse's chest from the front you should
see a chest that is wider at the bottom than the top.
The shoulder blades should be closer together at the top
near the withers than at the points of the shoulders where
the front legs extend downward.  If the shoulders are
too wide at the top the horse will have very low "mutton
withers" accompanied with a side to side motion when in gait
that is referred to as "rolling."   The rolling gait
is an uncomforatble ride and lacks the necessary agility to
be a top performance horse.

Narrow Chest:
A narrow chest is considered a major fault.  This is
Because there is not enough room between the front shoulders
and a horse cannot carry a lot of weight if the front end is
not wide enought to support it.   When the front chest
is not in correct proportion it also affects the withers and
the saddle may slip easily.   When the front is too
narrow it throws off the elbows and the front legs will not break
over correctly causing a number of traveling issues such as toeing out, or "plaiting" where the front feet cross over over another
and land directly in front of each other instead of tracking in
two lines.

Too-Wide Breast:
When a horse has a breast that is too wide he will almost
always have a rolling gait and paddle outward with the front
feet.   This hinders speed and efficiency of motion.
The faster the gait the more trouble he will display moving
his legs freely.  When the movement is hindered it will
affect speed and surefootedness.

Excellant example of a correctly "V" average chest

Base Wide Chest

Base Narrow Chest

Bulldog Chest

Click on the thumbprint to see a larger version of the photo.
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artist resins sculpted and or painted by them for sale.