Horse Anatomy

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Horse Anatomy
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Horse Anatomy

• Anatomy and physiology describe two complementary
  but different ways to look at the animal body.
• Anatomy
• Deals with the form and structure of the body and
  its parts
• Physiology
• Deals with the functions of the body and its
  parts.
• How things work and what they do.

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Horse Anatomy

• Microscopic vs Macroscopic anatomy
• Microscopic anatomy
• Deals with structures that are viewed with a
  microscope.
• Cells
• Tissues
• Macroscopic anatomy
• Also called gross anatomy
• Body parts large enough to see with the unaided
  eye.

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Horse Anatomy

• Another way to approach anatomy is to study
• Individual regions of the body
• Regional anatomy
• Individual systems of the body
• Systemic anatomy

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External Body Parts
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External Body Parts
1. Poll 2. Forehead 3. Face 4. Nostril 5.
Lips 6. Jaw 7. Throatlatch 8. Crest 9.
Neck 10. Jugular groove
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External Body Parts
11. Withers 12. Shoulder 13. Pt of
Shoulder 14. Chest 15. Arm 16. Elbow 17.
Forearm 18. Carpus or knee 19. Metacarpus or
cannon 20. Fetlock
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External Body Parts
21. Pastern 22. Coronet 23. Hoof 24.
Thorax 25. Girth 26. Abdomen 27. Flank 28.
Back 29. Loin 30. Croup
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External Body Parts
31. Pt of hip 32. Tailhead 33. Buttock 34.
Thigh or quarter 35. Stifle 36. Gaskin 37.
Tarsus or hock 38. Metatarsus
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Anatomical Planes

• The planes, The planes
• Median plan- divides animal symmetrically into
  right and left sides.
• Sagittal plan- any plan parallel to the median
  plan.

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Anatomical Planes

• Dorsal plan any no. of parallel planes that
  divides the body symmetrically dorsally and
  ventrally
• Transverse plan transect any anatomical part
  perpendicularly to its own long axis.

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Which way is which?

• Term Definition
• 1. Left The animals left
• 2. Right The animals right
• 3. Cranial Toward the head
• 4. Rostral Toward the tip of the nose (head
  only)
• 5. Caudal Toward the tail
• 6. Dorsal Toward the back
• 7. Ventral Toward the belly

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Which way is which?

• Term Definition
• 8. Medial Toward the median plan
• 9. Lateral Away from the median plan
• 10. Deep Toward the center (internal)
• 11. Superficial Toward the surface (External)
• 12. Proximal Toward the body
• 13. Distal Away from the body

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Which way is which?
Term Definition 14. Palmar Back of front leg
15. Plantar Back of back leg
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Horse Anatomy

• Body cavities
• Dorsal body cavity
• Ventral body cavity
• Cranial cavity
• Thoracic cavity
• Spinal cavity
• Abdominal cavity
• Diaphragm

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Horse Anatomy

• Levels of Organization
• Cells
• Tissues
• Organs
• Systems

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Horse Anatomy

• Cells
• The basic functional units of animal life
• Three general functions of most cells
• Maintenance
• Synthesis of cell products
• Cell division

• Components of cells
• Plasma membrane
• Cytoplasm
• Nucleus
• Ribosomes
• Endoplasmic reticulum
• Golgi apparatus
• Mitochondria
• Centrioles
• Microtubules
• Lysosome

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Horse Anatomy
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Horse Anatomy

• Components of cells
• Plasma membrane
• Boundary between extracellular and intercellular
  components
• Nucleus
• Contains and processes genetic information
• Controls cell metabolism and protein synthesis
• Ribosomes
• Site of protein synthesis
• Endoplasmic reticulum
• Transport and storage of materials in cells
• Synthesis of lipids, CHO, and secretory proteins

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Horse Anatomy

• Components of cells
• Golgi apparatus
• Packaging and alterations of substances for
  secretion or internal use
• Lysosome formation
• Mitochondria
• Site of ATP from respiration
• Lysosome
• Digestion of absorbed material
• Autolysis

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Horse Anatomy

• Components of cells
• Cytoplasm
• Media for transport of intracellular substances
• Centrioles
• Located near nucleus
• Play a role in cell division
• Microtubules
• Help give shape and form to the cell

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Horse Anatomy

• Types of Cells
• During morphogenesis, several types of animal
  cells are formed.
• Absorptive cells epithelial cells
• Secretory cells
• Nerve cells
• Sensory cells
• Muscle cells
• Reproductive cells

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Horse Anatomy

• Absorptive cells
• Often occur as continuous sheets on surfaces
  where material is transported to the cells.
• Found in the GI tract and kidneys
• Example Epithelial cells
• Secretory cells
• Produce products that are subsequently deposited
  in either the bloodstream or a special duct to an
  organ, where they are used.
• Pancreas and pituitary glands
• Spleen and lymph nodes

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Horse Anatomy

• Nerve cells
• Consists of a main cell body and a long thin
  structure known as an axon.
• Axon is covered w/ a layer of insulation called
  myelin.
• Axons carry electrical signals called nerve
  impulses.
• Main function is to transmit electrical messages
  from one part of the cell body to another.
• Connections between nerve cells are called
  synapses.
• These connections form an electrical network know
  as the nervous system.
• The processes that occur at the synapses are both
  electrical and chemical.

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Horse Anatomy

• Sensory cells
• Respond to impulses by emitting electrical
  signals.
• Example taste bud, smell receptors, hearing
  receptors, and sight.
• Muscle cells
• Three types skeletal, cardiac, and smooth
• Skeletal muscle are unique in structure
• Contraction of muscle fibers generate a
  mechanical force.

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Horse Anatomy

• Reproductive cells
• Gamets are formed after completion of the process
  of meiosis.
• Meiosis which halves the number of
  chromosomes in each cell.
• Stallion gamets spermatoza are motile
• Mare gamets ovum large and stationary

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Horse Anatomy

• Tissue are structured groupings of cells
  specialized to perform a common function
  necessary for the survival of the horse.
• Histogenesis process of tissue formation

• Tissue types
• Nerve
• Epithelium
• Muscle
• Connective
• Fluid

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Horse Anatomy

• Nerve tissue
• Consist of extraordinarily complex cells called
  neurons that respond in a specific way to a
  variety of stimuli so as to transfer information
  from one part of the body to another.
• Epithelial tissue
• Consists of a layer of cells covering the
  external surfaces of an animal and lining its
  internal tubes for digestion, respiration,
  circulation, reproduction, and excretion.
• Form
• Sensitive surfaces of sensory organs
• Glands
• Hair and nails

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Horse Anatomy

• Muscle tissue
• Ability to contract and relax and thus provide
  movement is characteristic of muscle tissue.
• Smooth muscle is activated by the autonomic
  nervous system.
• Skeletal muscle is controlled by the central
  nervous system and, to a certain extent, by the
  will.
• Cardiac muscle is characterized by its ability
  to contract rhythmically.

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Horse Anatomy

• Connective tissue
• Contain large amounts of extracellular material
  modified into different types.
• They are varied in structure to permit them to
  support the entire body and to connect its parts.
• Includes
• Fibrous tissue found in tendons and ligaments
• Elastic tissue found in ligaments between the
  vertebrae, arterial walls, and trachea,
  cartilaginous tissue found in joints and in the
  development of bones
• Adipose tissue which cushions and supports vital
  organs and stores excess food.

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Horse Anatomy

• Fluid tissues
• Are the blood and lymph
• These tissues function to
• distribute food and oxygen to other tissues,
• carry waste products from the tissues to the
  kidneys and lungs
• carry defensive cells and other substances to
  destroy disease producing agents.

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Horse Anatomy

• Organs
• Are a group of specialized tissues performing a
  specific function.
• Stomach organ of digestion
• Uterus organ of reproduction
• A group of organs working together is known as a
  system.
• Stomach is one of the organs in the digestive
  system.
• Uterus is only one organ in the reproductive
  system