The Muscular System

1. The Muscular System By Alexis DiStasio and Kate Brown

2. The Equine Muscular System • Large muscular system which allows movement • Gives a horse definition • Allows posture

3. 3 Types of Muscles • Smooth • Cardiac • Skeletal

4. Smooth Muscle • Found in digestive, circulatory, and urogenital systems • Sustained, rhythmic contractions • Made up of spindle-shaped cells with a single nucleus • Least specialized • Involuntary movement

5. Cardiac Muscle • Found only in the heart • Highly specialized • Rapid, rhythmical contraction and relaxation • Never tires, allowing heart to continually pump blood • Involuntary movement

6. 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

7. Riding Horse • Voluntary muscles are significant. • Flexor muscles: • bend joint • Extensor muscles: • straighten joints

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

10. Splenius • A triangular muscle • located on the side of the neck • Action- Acting alone, the splenius draws the head and neck towards the side

11. 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.

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

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

14. 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

15. External Intercostal • Aseries of thin, flat muscles between the ribs • Action - Move the ribs upward and forward and assist in inspiration.

16. Posterior Deep Pectoral • Broad flat muscle • Extends from under the abdomen • Action – to pull the scapula in a backward direction

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

18. 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

19. Slow-Twitch Muscle Fibres • Slow contractions and relaxation times • Used for maintaining posture when exercising at slow speeds • Gain energy to function through aerobic (oxygen) metabolism only • Activities such as driving, dressage, and endurance riding

20. Fast-Twitch Muscle Fibres • Two Kinds: • Fast-twitch, high-oxidative fibers • Fast-twitch, low-oxidative fibers

21. Fast-Twitch, High-Oxidative Fibres • Good oxygen capacity • Use oxygen to supply energy while working at high speeds • Gain energy through aerobic and anaerobic metabolism • Used during eventing, jumping, polo, and racing

22. Fast-twitch, Low-Oxidative Fibres • Does not have good oxygen capacity • Burn oxygen quickly • Used for short bursts of fast work • Anaerobic metabolism only

23. 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/Muscles-Of-The-Neck-Rhomboideus.html • Anatomy and Physiology of Farm Animals. Pages 164-65 • The Equine Body. By Beth Maloney (Chpt. 6)