The Equine Muscular System

Equine Science

MusclesO Function:

O Provide movementO Active organs of motionO Contract or change shape when

stimulatedO One or more nerves bring commands

AND send signalsO Red fleshO Make up about 50% of total body

weight

Types of Muscles

O Smooth (Involuntary)

O Cardiac (Involuntary Striated)

O Skeletal (Striated)

Smooth MuscleO Also called visceral muscleO Location:

O Digestive systemO Uterus

O Capable of prolonged periods of activity

O Peristalsis: wavelike contractions of digestive system muscles

O Contraction is involuntary

Cardiac MuscleO Location: ONLY found in the heartO Requires NO nerve stimulusO Requires NO conscious controlO Rate of contraction controlled by the

nervous system

Skeletal MuscleO Move the body voluntarilyO Usually attached to the bony levers

of the skeletonO Utilizes tendons to transmit the pull

of the muscleO Permits several muscles to attach at

one pointO Generally arranged in pairsO Become fatigued and require rest

Skeletal MuscleO Extensor: extends a joint and brings

bones into alignmentO Flexor: bends the jointO Some muscles can act as bothO Opposed muscles act successively

TendonsO Strong, cordlike structure that transmits

the pull of the muscle as it contractsO Tendon Sheath: synovial sac through

which a tendon passesO Tendon Bursa: synovial sac between

the tendon and the surface over which it passes in a change of direction

O Both secrete synovia for lubricationO Both usually found near joints

Five Major Functional Muscle Groups

O Forearms: allow for smooth gait and absorb shock

O Quadriceps: (hindquarters) used for propulsion

O Pectorals: carrying space for lungsO Back: support riders or packsO Stomach: hold organs in place