Veterinary Anatomy - Osteology PDF

Veterinary Anatomy A course ware prepared by Prof. Dr. Ashraf El Sharaby First Year First Semester Osteology 13 What’s Your Message? Oct 2024 Department of Anatomy & Embryology Faculty of Veterinary Me...

Veterinary Anatomy A course ware prepared by Prof. Dr. Ashraf El Sharaby First Year First Semester Osteology 13 What’s Your Message? Oct 2024 Department of Anatomy & Embryology Faculty of Veterinary Medicine Damanhour University  Locomotion and Adaptation Movement is an important feature of living organism. The movements result in change in location is called locomotion. Muscular movement e.g., skeletal, smooth and cardiac muscles bring locomotion. Locomotion is very important feature of animals. It helps them to go in search of food, shelter, mate etc. Locomotion  Locomotion and Adaptation Types of locomotion 1. Walking, running ‫ اﻟﺠﺮي‬/ ‫اﻟﻤ‬‫ش‬ ‫ي‬ 2. Jumping ‫اﻟﻘﻔﺰ‬ 3. Gliding ‫ت‬ ‫ اﻟ ﻟﻖ‬/‫اﻟ ﺣﻠﻖ‬ ‫ت‬ 4. Flying ‫اﻟﻄ ان‬‫ي‬ 5. Climbing ‫اﻟتﺴﻠﻖ‬ 6. Swimming and Diving ‫ اﻟﻐﻄﺲ‬/‫اﻟﻌﻮم‬ 7. Digging and Burrowing ‫اﻟﺤﻔﺮ‬  Types of locomotion Walking, running  Types of locomotion Walking, running  Animal Bones and Skeleton Animal Skeleton Objectives: 1. know the five functions of bones. 2. name and identify the parts of mature compact bone. 3. identify all the bones of the animal’s skeleton. 4. compare the bones of the skulls of the dog, cat, horse, ox, and pig for location, shape, and size. 5. compare the bones of the forelimb and hind limbs of the dog, cat, horse, ox, sheep, and pig for their number, location, shape, and size. Components of locomotor system: The locomotion apparatus represents an assembly of organs and structures concerned in the movement of animal. In addition, they give the basics of body conformation, stability and support. The locomotion apparatus is divided into: 1. Passive skeletal structures (i.e. bones & joints). 2. Active skeletal structures (i.e. muscles leading to contraction).  Functions of bones: 1. Giving body shape and support (i.e. skeleton). 2. A lever (i.e. bones of thoracic and pelvic limbs pull and push the body with the help of muscles. 3. Protect vital organs (i.e skull for the brain and thoracic cage for the heart). 4. As a mineral homeostasis (i.e 97% of body’s Ca++ found in the bone). 5. Hematopoietic organ (i.e hold bone marrow; source for blood cells, and site of B-lymphocytes maturation.  Animal Skeleton  Parts of Animal Skeleton AxialSkeleton Skull Vertebral Column Sternum Ribs  Parts of Animal Skeleton Appendicular Skeleton Girdle Limbs Identify the bones of animal Skeleton? Classification of bones According to shape, position & function: 1. Long or tubular bone:  Longer than wide.  Have a central cavity  Consists of a long shaft, proximal and distal extremities.  Found in the limbs.  Act as levers and also for support. Humerus and Femur are long. Proximal phalanx is a long bone. Ribs are elongated bones. 1. Long or tubular bone: 1. Long or tubular bone: 2. Flat bone:  Wide than they are long.  Thin, flattened and usually curved.  Furnishes sufficient muscle attachment.  Protects of vital organs which they cover. Scapula and Pelvic bone. Skull has flat bones. 2. Flat bone: 3. Short bone:  Roughly cube shaped.  Similar dimensions; length, breadth and thickness approximately equal.  Found in areas to diffuse concussion and diminish friction. Carpal bones are short. Tarsal bones are short. 3. Short bone: 4. Irregular bone:  Irregular shape, unpaired  Lie in a median position.  Serves for protection of vital organs as vertebral column for spinal cord and bones of cranium for brain.  These bones give also area for muscle attachment. Vertebrae are irregular bones. Cranium of skull has irregular bones. 4. Irregular bone: 6. Pneumatic bone: A flat bone contains air spaces instead of spongy substance and bone narrow. Lighten the bone weight. Protects underlying organs. Acts as a thermal insulator. Paranasal sinus walls are pneumatic bones. Avian bones are pneumatic.  Pneumatic Bones Frontal Sinus 5. Sesamoid bone:  Similar shape to Sesame.  Protects the tendon where it is exposed to friction (i.e. passes over a joint e.g. fetlock, coffin and stifle).  Increases mechanical effect of the tendon.  Changes the line of pull of the tendon. Proximal sesamoid bones. Distal sesamoid bone. Patella is a sesamoid bine 5. Sesamoid bone:  6. Visceral or Splanchnic bone: Specialized Bones Develop in soft organs Examples: os penis (dog and cat) and ossa cordis in the heart of ruminants Lateral view Canine os penis Dorsal view os penis Classifications of bones: #Structure  1. Compact bone: #Structure  It is the external dense substance.  It differs greatly in thickness according to stresses and strains on bones.  Microscopic unit is the Haversian system or osteon. Organize with Sections  2. Spongy bone:  Thin delicate boney trabeculae, run in various directions and are separated by marrow spaces with red marrow  Orientation of these trabeculae is affected by mechanical stress to the bone Classifications of bones: #Development 1. Endochondral bones:  They develop from hyaline cartilage precursors (i.e. metaphyseal plate).  All skeletal bones below the base of the skull are formed by endochondral ossification. 2. Intramembranous bones:  They develop from a fibrous membrane (mesenchyme).  All flat and cranial bones are formed by intramembranous ossification. Gross anatomy of bones Gross anatomical parts of long bone Long bone consists of 1. middle shaft or diaphysis contains the medullary cavity. 2. proximal extremity or proximal epiphysis comprises the spongy substance. 3. distal extremity or distal epiphysis comprises the spongy substance.  Anatomical structure of long bone The periosteum:  It is a specialized connective tissue membrane covers the bone outer surface except articular surface, which is covered by hyaline cartilage.  It consists of: 1. Outer protective layer of dense and irregularly arranged connective tissue. 2. Inner cellular layer contains osteogenic or proliferative cells.  Periosteum is fixed by Sharpey's fibers at outer layer of compact bone. It is continuous with joint capsules at the end of bones except the articular surface.  Anatomical structure of long bone Compact bone:  It forms the outer shell of the whole bone.  It is thick at the shaft and thin toward the extremities. Spongy bone:  Spongy or cancellous bone consists of a lattice of thin threads of boney trabeculae, which are less dense than the compact bone.  It is found at the extremities of long bones.  Their arrangement is specific known as trajectories, and it depends on mechanical pressure and the tensile forces that influence the bone. Anatomical structure of long bone Endosteum:  The endosteum is the inner thin fibrous membrane, which covers trabeculae of spongy bone.  It also lines the marrow cavity, marrow spaces and the Haversian canals.  It contains osteoblasts and osteoclasts. Marrow cavity:  It is the central cavity in the diaphysis which is compact in young and become large in adult.  It contains the marrow. Gross anatomical parts of long bone  Types of bone marrow – Red marrow: highly vascularized gelatinous tissue in which red and granular white blood cells are produced (hemopoiesis) » in young animals Gelatinous marrow » confined to the proximal end of Red marrow long bones, flat & short bones and axial skeleton in adults – Yellow marrow: waxy yellow fat whose hemopoiesis is inactive. May be reactivated by a fracture – Gelatinous marrow: in old aged animals. Chemical composition of bone Chemical composition of bone Organic matter (Ossein): 1. Cells such as osteoblasts, osteoclasts, osteocytes. 2. Osteoid; ground sulfated mucopolysaccharides. 3. Collagen fibers (1/3 bone weight & 1/2 volume. Organic mater gives bone toughness and elasticity helping to resist stretching and twisting. If removed (i.e.by heat), bone general form is kept but becomes lighter and becomes fragile. Inorganic matter: - Calcium and phosphates, giving hardness and resistance to compression forces. - If removed (i.e by EDITA), the bone losses rigidity and becomes flexible.   5% to 10% of cardiac output goes to bones.  Main bone vessel is the nutrient artery entering through nutrient foramen.  Lymph vessels are found in the periosteum and Haversian canals. Blood supply of bone Blood supply of bone: Three networks of arteries can be differentiated: 1. Nutrient artery 2. Periosteal arteries 3. Epiphyseal and metaphyseal arteries. Are their differences of blood supply between adult and young bones? ? Organize with Sections Organize with Sections Structure of young long bone 1. Periosteum 2. Compact substance 3. Spongy bone 4. Marrow (medullary) cavity 5. Endosteum 6. Bone marrow Notice growth zone “Epiphyseal cartilage” Insert blood supply in the illustrated bone! Structure of adult long bone 1. Periosteum 2. Compact substance 3. Spongy bone 4. Marrow (medullary) cavity 5. Endosteum 6. Bone marrow Insert blood supply in the illustrated bone!