The main purpose of the muscular system of all animals is movement. It is made up of muscle tissue, tendons and ligaments.
There are three types of muscle tissue smooth, cardiac and voluntary. The smooth tissue is found in the digestive tract and is automatic, the cardiac is specific to the heart and the voluntary are the muscles the animal consciously control.
Muscles are relaxed until they are stimulated by the nervous system and cause the muscles to contract. For an example, when an animal puts food in its mouth the trigger begins and the stimulation of the movements of the muscles in the face begins the process of the smooth tissues in the digestive tract.
The cardiovascular muscles are working constantly with every stimulus the heart the muscles contract and in turn creates the contraction throughout the vessel system.
When an animal senses danger a signal is sent from the brain to the voluntary muscles of the body. These signals from the senses allow the animal to run, change direction or hide.
The tendons of the muscular system are the tissue that attaches the muscles to the bones. They are made of collagen fibers and have a more stretching and flexible property than do ligaments. It is a major part of the body’s motion and bears the full stress of movement. Because of this horses are prone to tendon injuries.
The ligaments connect bone to bone and hold the skeletal system together. They are also composed of collagen fibers and are less flexible than tendons. They also take the full weight of motion and prone to stress injuries.
The muscular system is a major contribution to the health of the animal. It controls the immune system. When the body is inactive the immune system slows and thus weakens. A healthy muscular system needs to be active for the body to maintain its well-being.