Equine Science

loose connective tissue proper

"packing" materials of the body; fill space between organs, cushion and stabilize specialized cells in organs; support epithelia, blood vessels and nerves, store lipids; provide route for the diffusion of materials

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production; Krebs Cycle produces ATP

Pros of passive immunity

Provides a very quick, strong response to exogenous antigens

exocrine glands (epithelial tissues)

Secretions are discharged onto the skin or other epithelial surfaces via ducts; ex. enzymes entering digestive tract

What lymphocytes are involved in cell-mediated immunity?

T lymphocytes

active immunity

The immunity produced as a result of the administration of an antigen; immunity is usually long-term; exposure to the antigen or vaccination

reticular fibers (connective tissue fiber types)

Thinner, branching, interwoven framework called a stroma; Resist forces applied from many directions; stabilizes the parenchyma of an organ

vesicular transport

Transport of large particles and macromolecules across plasma membranes

Organs

a group of specialized tissues; cardiac muscles grouped together to form the heart

Systems

a group of specialized; the heart is grouped together with the vessels to form the cardiovascular system

Neurons (nerve cells)

a nerve cell; longest cell in the body; limited ability to repair because they cannot divide; cell body with a large nucleus; dendrites (receive information) are branching projections with one axon (carry information)

dense irregular connective tissue

able to withstand tension exerted in many directions; provides structural strength; Fibrous capsules of organs and of joints; dermis of the skin; submucosa of digestive tract.

muscle function

acetylcholine is the primary neurotransmitter to start muscle contraction

Packed Cell Volume (PCV)

amount of formed elements within the blood

synovial joints - components

articular cartilage; joint capsule: fibrous, synovial; joint space; joint fluid

ligaments

attach bone to bone; poor blood supply, take longer to heal

tendons

attach muscle to bone; decent blood supply, take time to heal

mononuclear cells (white blood cells)

be cells and plasma cells; t cells are responsible for cellular immunity

Erythrocytes (Red Blood Cells)

bioconcave cells that lack nuclei in their mature form when they are released fron the bone marrow; hemoglobin is a major cellular component; transport oxygen via "heme"; carbon dioxide binds to "globin"

fluid connective tissues

blood and lymph are connective tissues that contain distinctive collections of cells in a fluid matrix

tissue injuries

body attempts to restore homeostasis by causing inflammation and then regeneration can occur

growth abnormalities

bone can support more weight if static; dynamic forces across bone result in: shrinkage (atrophy), enlargement (hypertrophy), fractures, rearrangement of internal structure

appendicular skeleton

bones of the thoracic limb: scapula; humerus; radius/ulna; carpal bones; MC II, III, and IV; sesamoids; phalanges bones of pelvic limb: pelvis; femur; patella; tibia/fibula; tarsal bones; sesamoids; MT II, III, and IV; phalanges

components of skull

bones, sinuses, various foramen

short bones

carpal/tarsal bones; absorb concussion

Mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

Lysosomes

cell organelle filled with enzymes needed to break down certain materials in the cell; bud off Golgi apparatus

skeletal muscle tissue

cells are long, striated; located in combination with connective tissues and nervous tissues in the skeletal muscles, functions: to move and stabilize the position of the skeleton; guards entrances and exits; generates heat; protects internal organs

smooth muscle tissue

cells are short and nonstriated; involuntary muscle is found in the intestines where it pushes food along the digestive tract; found in arteries and veins

Neuroglia

cells that support; support structure of neural tissues; protect neurons; repair tissues after injury; provide nutrients to neurons

components of lymphatic system

cells, tissues, organs

vertebral column

cervical vertebrae: 7 (neck); thoracic vertebrae: 18; lumbar vertebrae: 6; sacrum; caudal vertebrae: 18

growth plate closures

close in more distal locations first; proxim ial locations occur later; spinal columen vertebral growth plates close last at age 5 1/2 to 6 years

dense regular connective tissue

collagen fibers are parallel and densely packed, aligned with the forces applied to the tissue; tendons and ligaments

Hemostasis

complex series of interactions triggered in the body to prevent hemorrhage (blood loss) 3 steps -constriction of blood vessels -platelet plug -clot formation

cranial and caudal nuchal bursae

cranial nuchal bursa is a synovial bursa located on C1; caudal nuchal bursa is a synovial bursa located on C2

Regeneration

damaged tissues are replaced or repaired

compact bone (cortex) components of a bone

dense type of bone that covers the external layers of most bones

calcification (growth of bone)

deposition of calcium salts in tissues other than osseous tissues

tissues within the lymphatic system

digestive, respiratory, urogenital; little pockets if lymphatic tissues that are the first to respond in local areas

endochondrial ossification (growth of bone)

during development, the skeleton is formed from cartilage that is gradually replaced by bone

nuchal ligament

elastic tissue composition provides passive support the weight of the head; head and neck work as a lever like at high speeds

growth of bone

elongation occurs along the growth plate (physis) that joins the ends to the shaft

4 types of tissue

epithelial, connective, muscle, nervous

Dense connective tissue proper

fibers densely packed; aka collagenous tissues because collagen fibers are the dominant fiber type

regeneration responses

fibroblasts lay down a collagenous framework to stabilize the injury site - scar tissue

classification of joints by tissue type

fibrous; cartilaginous; synovial

white blood cells (leukocytes)

fight infection

skull

flat bones joined by cartilage at birth; maturing the cartilage changes to bone, forming suture lines; process complete by 8 years old

interstitial fluid

fluid in the spaces between cells; bathes the external surfaces of the cells

serum

fluid portion of coagulated blood after centrifugation

components of bone

foramen (for passage of blood vessels and nerves)

muscular system

force behind levers; cover, protect and provide locomotion; assist with thermoregulation

ossification (growth of bone)

formations of bone by deposition of calcium salts in a matrix of osteoid tissue

lymph

forms as interstitial fluid that enters the lymphatic vessels that return the fluid to the cardiovascular system; immune cells monitor the lymphatic as it passes through the lymph nodes

synovial membranes

found in joint capsules; produce synovial fluid, lubricates joints

Equine Infectious Anemia (EIA)

highly infectious, viral disease of horses; transmitted from horse to horse via vectors (insects: horse flies, mosquitos); test by Coggins

fossa (surface features of bone)

hollow; sometimes gives an underlying muscle, bone, organ or gland more room to move

Serology

how to measure antibodies; can measure in foals; ex. Coggins

immune system suppressors

improper nutrition; illness, injury or stress; some medications; juvenile or senior age

connective tissue

includes bone, fat and blood; have specialized cells, extracellular protein fibers, have ground substance; never exposed to the outside; highly vascular with sensory receptors

inflammation responses

increase oxygen and nutrients; increase number and activity of phagocytes; release cytokines to stimulate immune system; remove toxins and waste products

nonspecific immunity - innate immunity

lacks

innate immunity (nonspecific)

lacks specificity and memory - mucous membranes, skin, and surface secretions

Pros of active immunity

lasts longer than passive

long bones

leg bones; support weight, aid in locomotion, store minerals, levers for joint movement

cardiac muscle tissue

located within the heart wall; function to circulate; maintain blood pressure

Collagen (connective tissue fiber types)

long, straight; most common fiber; formed from bundled fibers; flexible but strong as steel when pulled straight; tendons and ligaments

connective tissue proper

loose connective tissue (fat) and dense connective tissue (tendons)

Organs within the Lymphatic system

lymph nodes, tonsils, spleen, bone marrow

Platelets

membrane-enclosed packets of cytoplasm contain enzymes and special proteins; clotting response

hyaline

most common type of cartilage; tough but flexible; connections between ribs and sternum, nasal cartilage

Fibrocartilage

mostly densely woven collagen fibers; extremely durable and tough, absorbs compression; intervertebral discs, around a few joints and tendons

muscles of the head

motion of the head controlled by neck muscles; give horse expression; movement of lips, nostrils, ear, pinna, eyelids, jaw

Osmosis

movement of molecules from high concentration to low concentration through a membrane.

cells (within the lymphatic system)

neutrophils, lymphocytes and plasma cells, macrophages and monocytes

appositional growth (cartilage)

new layers of cartilage are added to the surface

articular (joint) surface

normally covered in cartilage; cartilage damage results in degenerative joint disease (chronic or osteoarthritis)

inflammation

one process to restore homeostasis after injury; swelling, heat, redness and pain to isolate damaged tissues and draw necessary chemical mediators

flat bones

pelvis/skull/ribs; enclose and protect vital cavities

functions of connective tissue

physical protection, support and structural framework of other tissue types, binding of structures, storage of energy reserves, transport of fluids and dissolved materials, immune protection

fluid component of blood

plasma; 92% water and 8% transported solids serum - plasma minus the clot constituents

muscle features

point of origin, a muscle belly (power), a point of insertion (motion)

Hematopoietic system

production of all types of blood cells from stem cells within the bone marrow; secondary site is the spleen and liver; blood stored in the spleen

process (surface features of bone)

projection on the bone; functions as a pulley for the muscles that run over it

Lymphatic System/Immunity

protection of the body against foreign invaders: bacteria, viruses, allergens, foreign materials, toxins

skeletal system functions

protection of vital organs; allow locomotion acting as levers; framework and support; framework and support; defense; blood formation;muscle attatchment

Tuberosity (surface feature of bone)

protrusion on the bone; usually a site of muscle attachment

functions of epithelial tissue

provide physical protection, control permeability, provide sensation, produce specialized secretions

Equine Infectious Anemia Chronic Disease

recurring signs: fever, edema, anemia, icterus, depression, weight loss; have to be quarantined for life

blood

red blood cells, white blood cells, platelets, plasma

epithelial glands

release hormones into the interstitial fluid and blood; secretions regulate activities of other tissues and organs

elastic cartilage

resilient and flexible; external pinna of ear; epiglottis and auditory tube

Leukocytes (White Blood Cells)

responsible for immune responses; Granulocytes- Neutrophils, Eosinophils, Basophils Agranulocytes (mononuclear cells) - Lymphocytes, Monocytes

Neutrophils (white blood cells)

segmented nucleus when mature; first line of defense; drawn in by chemical mediators

Equine Infectious Anemia (EIA) Acute Disease

signs occur within 7-10 days; depression, fever, pin-point hemorrhages on mucous membranes

Axial Skleton

skull; vertebral column: 7 cervical, 18 thoracic, 6 lumbar; 5 sacral; 15-25 coccygeal; sternum; ribs: 18 pairs

axial skeleton

skull; vertebral column; sternum; ribs

Thrombocytes (Platelets)

small cellular fragments that lack nuclei; Cytoplasmic, enzyme-containing fragments of large cells known as megakaryocytes; These cell fragments are important in the initial formation of blood clots

cells

smallest unit of life; ~200 different kinds of specialized cells; although different functions they have same structure

medullary cavity (marrow)

space surrounded by the cortex of a long bone; site of blood cell production

neural tissue

specialized for conduction of electrical impulses from one region of the body to another; 98% of neural tissue is in the brain and spinal cord

muscle tissues

specialized for contraction, which brings about movement; possess organelles and properties distinct from those of other cells

cancellous bone

spicules of bone interspersed with marrow components in the inner layers of a bone

supporting connective tissue

strong framework that supports the body; contain a matrix that includes numerous fibers; cartilage and bone

antigen

substance that triggers an immune response

cell-mediated immunity (a division of acquired immunity)

t cells have surface receptors that must be in contact with and respond to specific antigens. they will produce antibodies and interact with the foreign invader to destroy it

immunity

the body's defense

bone

2/3rds of the matrix consists of calcium salts; rest is collagen fibers; minerals are arranged around collagen fibers, making bone hard, and strong

muscles of the neck in the horse

24 pairs; arch, strengthen' lift, bend, rotate head and neck; heavy weight counterbalance the weight of the body

equine blood

7-9% of body weight; ~40 liters; can loose up to 1/3 of total volume slowly; can lose 1/4 of total volume until serious problems

epithelial tissue

A body tissue that covers the surfaces of the body, inside and out; skin, digestive tract, respiratory tract; reproductive and urinary tracts

Endoplasmic Reticulum

A cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another.

Anemia

A condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume.

Cartilage

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together; chondrocytes only cells in the matrix; avascular, nutrients and waste go through the matrix

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Cytoskeleton

A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement

Nucleus

A part of the cell containing chromatin that carries DNA and RNA and responsible for growth and reproduction

Plasma Membrane

A selectively-permeable phospholipid bilayer forming the boundary of the cells; water passses freely

isotonic solution

A solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution

hypertonic solution

A solution in which the concentration of solutes is greater than that of the cell that resides in the solution; the cell will shrivel up, pulls the water out of the cell

hypotonic solution

A solution in which the concentration of solutes is less than that of the cell that resides in the solution; the cell will swell and possibly explode

Golgi apparatus

A system of membranes that modifies and packages proteins for export by the cell; cis face receives materials from the E.R. and the trans face releases substances for transport

antibody

An antigen-binding immunoglobulin, produced by B cells, that functions as the effector in an immune response.

humoral immunity (a division of acquired immunity)

B cells produce antibodies after exposure to specific antigens; long memory; acquired through exposure or vaccination

What lymphocytes are involved in humoral immunity?

B lymphocytes

Meiosis

Cell division that produces reproductive cells in sexually reproducing organisms

Vacule

Cell organelle that stores materials such as water, salts, proteins, and carbohydrates

interstitial growth (cartilage)

Chondrocytes divide and the daughter cells produce new matrix, expanding cartilage from within

elastic (connective tissue fiber types)

Contain the protein elastin; Elastic fibers are branched and wavy; After stretching, they will return to their original length; Component of blood vessels; Elastic ligaments are dominated by elastic fibers

Endocytosis

Endo (within) cytosis (cell) is a process in which a substance (e.g. proteins) gains entry into a cell without passing through the cell membrane

active transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

Exocytosis

Exo (exit) cytosis (cell) is a process in which a substance is exited from the cell without passing through the cell membrane

Tissues

Groups of cells with a common structure and function; myocytes grouped together to form tissues known as muscles

aquired immunity

Immunity obtained from the development of antibodies in response to exposure to an antigen.

masseter muscle in horses

Large mastication muscles that form the jowl of the horse; Attach along facial crest and zygomatic arch; Insert along outer curve of the mandible; chew food

Plasma

Liquid part of blood; in the vessels of the circulatory system

Ribosomes

Makes proteins (on rough e.r.)

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration

facilitated diffusion

Movement of specific molecules across cell membranes through carries proteins

joint

the junction of 2 or more bones

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

passive immunity

the short-term immunity that results from the introduction of antibodies from another person or animal; administration of colostrum from mare to foal

Periosteum

tough outer membrane of bone which supplies the innervation and vasculature fro the outer layers of bone; covers entire outer surface of bone, except for articular surfaces

Functions of blood

transport of oxygen from lungs to peripheral tissues and cells; transport carbon dioxide; distribute nutrients; transport waste products to kidneys; transport hormones; aid in heat regulation; maintain body pH; aids in preventing blood loss; assist in immune system

red blood cells (erythrocytes)

transport oxygen and carbon dioxide via hemoglobin molecule

growth of long bones

two ends (epiphysis) and a shaft (diaphysis)

immune system enhancers

vaccination; proper nutrition; good physical condition; regular routines, low to moderate stress

irregular bones

vertebral column; protect spinal cord