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The Horse's skeleton
You can find more about horses here
The skeleton comprises of about 210 bones:
• 37 in the skull, including 3 small bones in each ear (auditory ossicles),
• 2 branches of mandible (lower jaw)
• 54 vertebrae (7 cervical, 18 thoracic, 6 lumbar, 5 sacral, 15 - 20 coccygeal),
• 36 ribs (some breeds sometimes have 37 or 38),
• 1 sternum,
• 40 in the forelimb
• 40 in the hindlimb (including pelvis)
The horse has no collarbone so therefore the front legs are not attached by joints, meaning purely a sling of muscles and ligaments supports the weight of the horse and rider. This is part of the shock absorbing mechanism of the front legs, which also includes all the angles and joints of the front leg.
Horse's can sleep in the upright position without falling over due to a 'locking' mechanism in the fore and hindlimbs. The main joints can be locked into position by a system of muscles and ligaments mostly based around the suspensory ligament at the back of the cannon bone. In this position very little energy is needed to hold the 'lock'.
A joint is the location at which two bones make contact (articulate). Joints are constructed to both allow movement and provide mechanical support.
The horse's joints are designed to efficiently absorb shock, permit frictionless movement, and effectively bear the weight of a body that can weigh 1,200-1,500 pounds (550 - 650 kg) or more. Each joint is stabilized by a complex network of tendons, ligaments, and muscles. When all is well, this complex network enables a joint to function in a smooth, synchronized fashion. However, when any part of the network malfunctions because of injury or disease, repair via medical treatment might be necessary.
Skeleton of a horse
1 = Lower jaw
(mandible) of the skull
2 = Upper jaw (maxilla) of the skull
3 = Cervical vertebrae (bones of the neck).
4 = Scapula (shoulder blade)
5 = Shoulder joint
6 = Humerus (arm bone)
7 = Elbow joint
8 = Forearm:
8a = Ulna
8b = Radius (forearm bone)
9 = Carpus (wrist bone)
9a = Accessory Carpal bone
10 = Cannon bone (Metacarpus)
11 = Kogelgewricht
12, 13 and 14 are the three phalanges:
12 = Long pastern
13 = Short pastern
14 = Coffin bone (pedal bone)
15 = Rib
16 = Thoracic vertebrae (the bones that form the dorsal part of the thoracic cage)
17 = Lumbar vertebrae (the bones of the lumbar region of the back)
18 = Sacrum (the set of sacral vertebrae)
19 = Caudal vertebrae (the bones of the tail)
20 = Pelvis
21 = Hip joint
2 = Upper jaw (maxilla) of the skull
3 = Cervical vertebrae (bones of the neck).
4 = Scapula (shoulder blade)
5 = Shoulder joint
6 = Humerus (arm bone)
7 = Elbow joint
8 = Forearm:
8a = Ulna
8b = Radius (forearm bone)
9 = Carpus (wrist bone)
9a = Accessory Carpal bone
10 = Cannon bone (Metacarpus)
11 = Kogelgewricht
12, 13 and 14 are the three phalanges:
12 = Long pastern
13 = Short pastern
14 = Coffin bone (pedal bone)
15 = Rib
16 = Thoracic vertebrae (the bones that form the dorsal part of the thoracic cage)
17 = Lumbar vertebrae (the bones of the lumbar region of the back)
18 = Sacrum (the set of sacral vertebrae)
19 = Caudal vertebrae (the bones of the tail)
20 = Pelvis
21 = Hip joint
22 = Femur (thigh
bone)
23 = Stifle joint
23a = Patella (bone that allows the flexion of the thigh on the gaskin), knee cap
24 = Lower leg:
24a = Tibia (leg bone)
24b = Fibula
25 = Tarsus (bone forming the joint between the tibia and the metatarsus), hock joint
26 = Metatarsus (hock bone)
27 = Sternum (bone forming the underside of the thoracic cage)
a = Splints (On each side of the cannon bone is a small bone known as the splint bone. Remnants of an earlier time when horses had five toes. The inner bone is usually slightly larger than the outer bone.)
b = Sesamoid bones
c = Navicular bone (The navicular bone functions as a fulcrum for the deep flexor tendon that passes underneath it and attaches to the coffin bone)
d = Fetlock joint (between cannon bone and long pastern bone)
e = Pastern joint (between long and short pastern bone)
f = Coffin joint (between short pastern bone and coffin bone)
23 = Stifle joint
23a = Patella (bone that allows the flexion of the thigh on the gaskin), knee cap
24 = Lower leg:
24a = Tibia (leg bone)
24b = Fibula
25 = Tarsus (bone forming the joint between the tibia and the metatarsus), hock joint
26 = Metatarsus (hock bone)
27 = Sternum (bone forming the underside of the thoracic cage)
a = Splints (On each side of the cannon bone is a small bone known as the splint bone. Remnants of an earlier time when horses had five toes. The inner bone is usually slightly larger than the outer bone.)
b = Sesamoid bones
c = Navicular bone (The navicular bone functions as a fulcrum for the deep flexor tendon that passes underneath it and attaches to the coffin bone)
d = Fetlock joint (between cannon bone and long pastern bone)
e = Pastern joint (between long and short pastern bone)
f = Coffin joint (between short pastern bone and coffin bone)
Comparison of the bones of a man and a horse.
What are the normal vital signs of a normal horse?
• Heart Rate: 30-40 beats a minute at rest (higher for younger horses). Take pulse from under the left side of the chest near the elbow. Over 80 at rest is a serious problem.
• Respiratory Rate: 12-20 beats per minute at rest.
• Internal BodyTemperature: about 37.5 degrees Celsius. If above 39 degrees Celsius, contact your veterinarian immediately. Non-breakable thermometers in the anus work best--just don't lose it. Some tie a cord to it and alligator clip it to horse's tail.
Here you can see the digestive system of a horse
Here you can see the skeleton of a dog
Here you can see an X-ray of a cat
