Equine Anatomy Equine Science I Scott Robison Knightdale High School

Major External Parts Barrel- central region from the back to the abdomen Corenet- dividing line between the hoof and the leg (in coronary band) Fetlock- joint connecting the cannon and the pastern above the hoof Flank- fleshy side between the ribs and hip

Major External Parts #2 Forelock- lock of hair falling forward over the face Heart Girth (Girth)- circumference of the chest just behind the withers and in front of the back Hock- large joint half-way up the hind leg of the horse Mane- long hair on top of the neck

Major External Parts #3 Muzzle- lower end of the nose which includes nostrils, lips, and chin Pastern- part of the leg between the fetlock joint and the coronary band Poll- top part of the head between ears Shoulder- part extending to the base of the neck that connects the forelimbs to the body

Major External Parts #4 Stifle- knee-like joint above the hock in the hind leg Thigh- part of the hindquarter between the stifle and the rump (croup) Withers- highest part of the back located at the base of the neck Croup- rump/hip area

External Anatomy Terms The hip area is also called the hindquarter The topline is the back and loin from the withers to the croup. The topline is also referred to as the length of the back The underline is the area from the elbow to the stifle

Muscular System Consists of all of the muscles in the body of the horse Muscles are supported by the skeletal system Muscles are attached to bones by tendons Muscles move bones by contracting and relaxing

Tendons Connect bones to muscles Encased in thin, fibrous sheets called tendon sheaths Tendon sheaths lubricate the tendon so they move more freely Warning: Graphic image on next slide

Ideal Muscles Neck muscles should be long, smooth and flat –Affect the ease and freedom of movement of the forelegs Forearm muscles should be long, lean and attach to the bone close to the knee –Allow long strides Long, tapered muscles in the hindquarter provide speed Bulging muscles in the hindquarter provide more power

Swayback Swayback is a term used to describe a condition where the horses back sags, especially when ridden Good muscling in the back and loin support the vertebral column and prevents swayback

Internal Organs Organs are in three major cavities (areas) of the horse: –Thoracic Cavity (front) –Abdominal Cavity (middle) –Pelvic Cavity (back)

Thoracic Cavity The thoracic cavity is the area between the neck and abdomen. Ribs form the sides of the thoracic cavity The organs of the thoracic cavity include the circulatory and respiratory systems.

Thoracic Organs The heart lies towards the bottom of the thoracic cavity and to the left of center. The lungs lie to the sides and behind the heart and fill most of the thoracic cavity.

Abdominal Cavity The abdominal cavity extends from just behind the thoracic cavity to the pelvic region. The diaphragm is a body partition of muscle and connective tissue. The diaphragm separates the abdominal and thoracic cavities.

Abdominal Organs The liver is a large organ extending all the way across the abdominal cavity. The spleen and stomach lie behind the liver and in front of the small and large intestines. The kidneys lie on each side of the backbone and under the last ribs in the loin area of the horse.

Pelvic Cavity The pelvic cavity is continuous with the abdominal cavity. The rectum is the terminal portion of the intestine, which continues from the abdominal cavity to the pelvic cavity. The urinary bladder lies within the pelvic cavity and extends into the abdominal cavity when full.

Pelvic Organs Major organs included in the pelvic cavity are: Male reproductive organs which lie toward the back and at the base of the pelvic cavity; or, Female reproductive organs extending from the back of the cavity to near the abdominal cavity.