Animal Health Flashcards
Health
normal physiological state
Disease
-absence of health, normal functions disturbed
-can lead to morbidity
-can lead to mortality
endemic disease
always present within a certain population
epidemic
increase in number of cases, outbreak
pandemic
uncontrolled epidemic
infection
organism enters your body and causes disease
non-infectious disease
not transmitted between animals (genetics, environmental)
contagious disease
easily transmitted between animals
non-contagious disease
poorly transmitted
clinical disease
signs of disease readily apparent
subclinical disease
no overt signs of disease
acute disease
sudden onset of clinical signs, short duration
chronic disease
signs develop slowly, last for a long time
zoonotic disease
passed from animals to humans (and vis versa)
Signs of disease
sick animals often exhibit:
-appetite loss
-listlessness, depression
-droopy ears
-head held low, arched back
-isolate
-coughing, wheezing, labored breathing
-stiff, labored movement
-loose stools (enteric disease
Pathogenic disease
-caused by an infectious organism
-pathogenicity=ability of an organism to cause disease
-virulence=severity of disease and the ability to overcome the host’s (animal’s) immune system
Bacteria
-small, single celled prokaryote=no nucleus, membrane-bound organelles
-can be found everywhere
-classified by shape, structure, cell wall
-not all cause disease=some beneficial to us, microbiota, probiotics in yogurt
-bacterial infections can be treated with antibiotics
Viruses
-NOT cells
-contain genetic material (DNA or RNA), protein coat (capsid)= some enzymes, outer envelope
-Can only replicate within the host= lytic cycle, lysogenic cycle
-cannot be controlled by antibiotics= antibiotics can help prevent secondary infection, treat symptoms, some antiviral drugs
Fungi
-small eukaryotes= singular or multicellular
-spread through dispersion of spores
-can be beneficial= yeast, mushrooms, lichen
-fungal disease can be confined to a body surface, or be systemic
-can infect plants, animals, humans, even other parasites
-treatment: antifungal drugs
Parasites
-one organism benefits by harming the host
-affect all living species
-Ecto- (outside host, fleas) or endo- (inside host, tapeworm) parasites
-signs of parasites= itching of rectal area, abdominal pain, weight loss, anemia, depression
Physical Injuries
-disrupt normal physiological processes
-due to handling
-due to inadequate, unkept facilities
-animal fighting
-predator
-accidents
Metabolic Disease
-nutrition related
-Over- or under- feeding
=nutrient deficiencies
=nutrient toxicities
-Toxins in plants/feed
Immune System
-Immunity= protection from infectious agent
-innate immunity
-acquired immunity
Innate immunity
=defense you are born with
=some immune cells, barriers to entry (skin, mucus)
=non-specific
Acquired immunity
-defense that develops with exposure/time
-specific
-diversity, memory, tolerance
Active immunity
-developed after exposure to infection/vaccine
-Natural= response to previous infection
-Artificial= response to a vaccination
Passive immunity
-develops when antibodies are received from somewhere/someone else
-natural= received from mother (colostrum, placenta, eggshell)
-Artificial= received from medicine (gamma globulin injection)
Immune lines of defense
- innate barriers- skin, mucus membranes, epithelia (intestine, lungs)
- innate immune cells- nonspecific white blood cells
- Acquired immunity- specific white blood cells (B and T cells)
- Barriers to entry
-Goal= keep organisms out
-Any “surface” = skin, gut, lungs, eyes/nose/month
-several mechanisms of protection
-mechanical= movement of air, fluid
-chemical- enzymes, pH, mucus, antimicrobiological
-Microbiological= normal microbiota
- Nonspecific (innate) immune cells
-Goal: kills things that get in
-Recognize genetic, conserves patterns associated with pathogens
-Phagocytosis= type of innate cell that consumes and destroys pathogen, antigen presenting cells
-inflammation= bring things to site of barrier breach
-fever
- Specific (adaptive) immune cells
-target response to specific pathogen
-recognize antigen= specific substance found on foreign microbe
-cell mediated= cytotoxic T cells destroy infected body cells
-Humoral= B cells produce antibodies that bind pathogen and impair or kill them
-regardless, memory cells remain in case of future infection
Treatment/prevention of disease
-over the counter medication
-prescription
-extra label use
-off label
Over the counter medication
can be purchased in stores
Prescription
only acquired and used by order of licensed veterinarian
Extra label use
veterinarian prescribes medication for something other than what label indicated. Legal.
Off label
drug used in manner other than indicated by manufacturer or veterinarian. illegal.
Routes of administration
-subcutaneous (SQ)
-Intramuscular (IM)
-Intravenous (IV)
-Nasal
-Oral
-Topical
Location of administration
-with livestock, avoid high-value cuts of meat= neck and skin around elbows are ideal for injection spots
-injections can cause abscesses, scar tissue, that damage muscle
-must be discarded from carcass at slaughter
Vaccines
-trigger antibody production against a specific pathogen
-serval forms
Vaccines- trigger antibody production against a specific pathogen
-no infection with actual pathogen
-body still produces memory response
Live
weak or modified from that does not produce disease
killed/inactivated
proteins or small pieces of pathogen
Toxoid
toxin produced by pathogen
biosynthetic
artificial substance similar to pathogen of interest
mRNA
gives the mRNA instructions to make viral antigen that body will then produce an immune response to
How Antibiotics Work
-Kill or inhibit growth of bacteria= damage cell walls, block metabolism
-treat existing infection or prevent outbreak= injection, delivered in feed or water
-some specific, others target broad categories= will kill good bacteria as well
How does antimicrobial resistance work?
-Bacteria can develop resistance through random mutations= spread through division, transfer between other bacteria
-when antimicrobials used, kills all bacteria, except for those with resistance
-resistant bacteria now have preferred conditions= take over
-continue to spread and transfer their resistance
Biosecurity
-Mitigates risk of disease outbreak
-Includes: assess disease potential
=increase animal resistance
=isolate new animals
=traffic control
=cleaning (sanitation, disinfection, and sterilization)
mRNA
gives the mRNA instructions to make viral antigen that body will then produce an immune response to
withdrawal
time required after treatment before animal can enter food chain
