Introduction, Basic Definitions Flashcards
Principles of health and disease
fragile equilibrium between host and pathogen
principles of defense against disease
immunology
Infectious disease by:
bacteria, viruses, parasites
epidemiology
how micro-organisms spread
Micro-organisms
are everywhere: on you, in you, next to you, far away
are part of life and the whole ecosystem
extremophiles
live in extreme conditions
Free living bacteria
no importance for animals and disease
part of the ecosystem
Obligate Symbionts
need host to live together
ex. chlamydia
Facultative Symbionts
can go into another ecosystem but have to go with another organism sometimes
Non pathogenic
not doing any harm to you in normal conditions
Facultative pathogenic
under certain conditions can give you disease (stress)
endogenic infections
exogenic infection
Endogenic infections
under certain conditions could get infected
could be on skin but don’t get infected
Exogenic Infection
comes from outside
bacteria you get from another animal or person
Obligate pathogenic
always causing disease or infection
Balanced pathogenicity
damage with recovery
majority!
Unbalanced pathogenicity
high damage/death
ex. liver damage that cant come back leads to death
Infection
invasion and multiplication of micro-organism
eventually with disease
goes into body of animal and starts to replicate
Disease
structural and functional damage
subclinical disease
lousy day, dont fele well but not really sick
ex. subclinical mastitis- see reduction in milk production but dont see infection of udder
Opportunistic disease
precondition before the disease is showing
could be caused by viral infection- virus makes the damage but bacteria sneaks in
ex. need surgery to get infected or irritation
Septicaemiae
goes into blood stream
bacteraemia
bacteria in blood, infections in white blood cells
Hyperacute
farmer goes to bed and the next day finds all animals sick or dead
Acute
see animal and can tell its not feeling well
next day notice hes sicker
evolves quickly
Subacute
little bit slower, animal gradually gets worse
takes a couple of weeks
the longer you wait the harder it is to treat
chronic
hard to cure, bacteria hide somewhere
ex. tuberculosis
Disease causing micro organisms
minority
our innate immunity can handle to a certain extent
have a certain amout in system without showing disease (facultative pathogen)
Escherichia Coli
facultative pathogen
carried in the intestines of older pigs and in poultry
when stressed, immunity lowers causing other diseases
Staphylococcus aureus
facultative pathogen
in humans 1/3 permanent colonized, 1/3 intermittent colonized, 1/3 never colonized
diseases: mastitis, skin infection, septicaemiae
Three Kingdom Classification
Bacteria, Archaea, Eukarya
Procaryota
Bacteria, Archaea
Mycology
Chromista, Fungi
Bacteria
less than 5 micrometers
no membrane bound organelles (instead invaginations of plasma membrane)
70 ribosomes
single molecule- circular nucleic acid
nuclear membrane is absent
replication by binary fission (more mutations happen)
Eukaryotes
greater than 10 micrometers membrane bound organelles present 80S ribosomes nucleic acid in chromosomes nuclear membrane is present replication by mitosis
Antibiotic Target
70 ribosomes- bacteria
80S ribosomes- Eukaryotes
Morphology- special forms
gram negative
ex. spirochetes: leptospira
gram positive
ex. actinomycetes, mycoplasma
Bacterial Names
Genus: capital and italic
Species: italic
Subspecies: italic
Serovar or other: not italic, capital
