Equine Muscular System

Function of the Muscular SystemA. Provides movement in conjunction

with the skeletal system

B. Important in life support

C. Used by some humans for food

Classifications of MusclesA. Voluntary

Movement of the muscle is under the control of the animal

B. Involuntary Movement of the muscle is not controlled by the

animal

Types of Muscles

A. Smooth Muscles Involuntary muscles,

found in the walls of internal organs and the blood vessels.

Fibers are under involuntary control and appear spindle-shaped.

Types of Muscles

A. Cardiac Muscles Muscles that form a

network to make up the heart.

Types of Muscles

A. Skeletal Muscles: Have a striped

appearance, include voluntary and involuntary, attached to and moves your bones.

This is a majority of the muscle tissue in your body.

The Muscle SystemA. Brachiocephalicus

located in the neck, running from the head to the humerus, allows the foreleg to move forward and effects movement in the shoulder,

such as when the horse is in collection, the shoulder is raised.

B. Deltoidus  located over the shoulder, begins at the scapula and

runs down to the humerus, enables flexion of the foreleg.

Brachiocephalicus

Deltoidus

The Muscle SystemC. Triceps Brachii 

involves 3 muscle strands, it is the most important muscle that extends the elbow.  

The 3 strands run from the scapula and humerus into the ulna at the top of the forearm.

D. Pectoralis  Goes from the sternum to the humerus.  This is one of

the 4 muscles that make up the Pectorals.

Pectoralis

Triceps Brachii

The Muscle SystemE. External Obliquus Abdominis 

The largest of the abdominal muscles, running backwards

This muscle aids flexion of the back, and assists in exhaling.  

F. Trapezius  Located in the neck and is a wide muscle of 2 bands

that start on the top side of the neck and run down to the shoulder area.  

These muscles help to raise the shoulder.

External Obliquus Abdominis

Trapezius

The Muscle SystemG. Latissimus Dorsi 

Supports the back, helps to pull the body forward during movement.  Runs from the top of the back forward to the shoulder and humerus.

H. Quadreceps Femoris  Located in the hind quarters and has 4 strands of

muscle, working together they help with extension of the stifle joint and flexion of the hip.

Latissimus Dorsi

Quadraceps Femoris

The Muscle SystemI. Superficial Gluteal 

runs across the hip and down to the femur.   This muscle that enables flexion of the hip and the

forward movement of the joint.   It is a thick and fleshy muscle, which gives the shape

of the croup.   Used in kicking and rearing movements.

Superficial Gluteal

The Muscle SystemJ. Biceps Femoris 

Is located in the hind quarters, allows the hind leg to extend,  allows abduction of the leg, and such movements as rearing and kicking. 

K. Deep Digital Flexor Is part of 3 strands of muscle in the hind leg, joining the

humerus and the bones of the lower leg, it extends the elbow, and flexes the carpus and lower leg.

Biceps Femoris

Deep Digital Flexor

Equine AnatomyMuscular System The muscular system provides movement both internally

and externally. Muscles are the active organs of motion and are

characterized by their property of contracting or changing shape when stimulated.

Each muscle is supplied by one or more nerves that bring commands from the brain to make it contract.

Equine AnatomyMuscular System Muscles compose about 50 percent of the total body

weight. The muscle system is made up of three types of muscles

smooth or involuntary, cardiac or involuntary striated, and striated or skeletal muscle.

Myopathies/MyositidesA. Myopathies

diseases that primarily cause damage to muscles. They may be present at birth (congenital) or occur due to nutritional imbalances, injury, or ingestion of a poisonous substance.

B. Myositides diseases that produce a mainly inflammatory reaction in

muscle. Common causes include infections, parasitic diseases, and immune-mediated conditions.

Myopathies/MyositidesA. Immune-mediated Myositis

B. Fibrotic and Ossifying Myopathy in Quarter Horses

C. Hyperkalemic Periodic Paralysis

D. Rhabdomyolysis

E. Steatitis

F. Selenium or Vitamin E Deficiency

ProjectA. Pick one of the Diseases on the power point and research it

B. Have the following Etiology/Pathology/Epidemiology Signs Diagnosis Treatment Control/Prevention

C. Poster / Paper/ Presentation

D. Present in class You will be teaching the class about the disease 5-10 minutes long

E. 150 points