Equine Anatomy

1. Equine Anatomy Equine Science I Scott Robison Knightdale High School

2. 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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

10. 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

11. 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

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

13. 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.

14. 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.

15. 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.

16. 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.

17. 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.

18. 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.