Muscular system

The horse has a large muscular system which

allows movement of the horse, gives it definitions as well as allowing posture like

standing by contracting both muscle groups at the same time.

3 Types of Muscles

• Smooth

• Cardiac

• Skeletal

Smooth muscle

Smooth Muscle

• Found in digestive, circulatory, and urogenital systems

• Sustained, rythmic contractions• Made up of spindle-shaped cells with a single

nucleus• Least specialized• Involuntary movement

Cardiac muscle

Cardiac Muscle

• Found only in the heart• Highly specialized• Rapid, rhythmical contraction and relaxation• Never tires, allowing heart to continually

pump blood• Involuntary movement

Skeletal muscle

Skeletal Muscle

• Most highly specialized• Used for movement and can contract quickly• Function: to provide powerful, rapid

contractions to allow locomotion• Attached to limbs of skeleton• Voluntary – controlled by brain and nervous

system

When considering the anatomy of a riding horse it is the voluntary muscles which are

significant. These are divided in to two groups - Flexor muscles which bend the joint and

extensor muscles which straighten the joint. When a horse is standing both muscles act simultaneously to stabilize the joint, thus

preventing either flexion or extension.

Rhomboideus

• This is a long triangular muscle • located at the top of the neck• Action - To draw the scapula upwards and

forwards

Splenius

• A triangular muscle• located on the side of the neck• Action- Acting alone, the splenius draws the

head and neck towards the side

Trapezius

• Situated on the side of the neck and withers.• It is a triangular muscle• Action - acting alone the trapezius pulls the

shoulder upwards and forwards.

Latissimus dorsi

• Located on along the back down to the chest• Acting alone helps move the front legs and

chest

Superficial Gluteus

• The most superficial muscle of the croup.• It is V-shaped• Action – move the thigh outward

Biceps femoris

• long, thick, muscle• extending from the superior part of the croup

to the stifle• Action- It flexes the tibia and with assistance

helps in the act of rearing

External Intercostal

• A series of thin, flat muscles between the ribs • Action - Move the ribs upward and forward

and assist in inspiration.

Posterior Deep Pectoral

• Broad flat muscle • Extends from under the abdomen • Action – to pull the scalpula in a backward

direction

Branchiocephalicus

• Long, thick muscle • located in the neck• Action - help move the neck

Masseter

• Thick square muscle • Located on the lower jaw • Action – brings the teeth of the lower jaw and

the teeth of the upper jaw together

Work Cited • http://www.eec-equine-therapy.com/Muscular-System.html

• http://www.irishhorsesociety.com/horsedata/muscles.htm• http://chestofbooks.com/animals/horses/Health-Disease-Treatment-2/Mu

scles-Of-The-Neck-Rhomboideus.html