what does placing a transport swab in the fridge accomplish?
slows growth of bacteria
pink curvy rods on a smear...how would they react in the fridge?
picture of gram positive rods "look like Chinese charaters" how would you describe it, what does it look like?
pleomorphic, remember: corneybacterium
two major attributes of pasturella
coccobacilli and bipolar staining
does mycoplasma stain well with grams?
no...mycoplasma doesnt have a cell wall to stain with grams
is tetanus contageous?
endotoxins are secreted from
only Gram negative bacteria
are penacillins bacteriostatic?
no theyre bacteriocidal
is clavamox good to treat mycoplasma?
exotoxins are produced by...
gram positive and gram negative
does doxycycline affect gram neg bacteria?
are capsulated bacteria virulent?
what forms a spore and a capsule?
no gram stain worked on a bacteria. what antibiotic would you use?
what is the amount times (multiplied) the MIC (minimum inhibitory concentration) to treat something?
3-5X MIC at target site
is clorhexadine sporicidal?
what is an endotoxin?
LPS's from the cell wall of gram negative bacteria
which is false? a. Penicllins inhibit cell wall synthesis b. Clavulanic acid is a beta-lactamase inhibitor c. Sulfonamides and trimethoprim should not be used together because of their antagonistic activity d. Antibacterial drugs are not effective against fungal infections e. Gentamicin is more likely to be effective against Psuedomonas than neomycin?
are transport swabs designed for bacteria to multiply when refrigerated?
bascillus anthrasis, clostridium tetani (bascillus and clostridiums all do)
corneybacterium would be described as?
what causes something to be stained gram positive?
gram stain sticks on/into big layer of peptidoglycan of cell wall
what do you stain mycobacterium with?
acid fast (wall too thick to use grams)
what do you use negative staining on, what is the stain?
encapsulated bacteria....india ink
what do you stain leptospirosis with?
gemsa or silverstain
what are pilli
short adhesion filament
bipolar stain is what bacteria?
what does gram positive mean?
peptidoglycans in cell wall (P as in positive)
what does gram negative mean?
lipopolysaccharides in cell well (L as in loser as in negative attribute)
mastitis is caused by
Staph(treat with clavamox) and Norcardia(treat with tetracycline, erythromycin, or Trimethoprim-sulfadiazine ) both cause mastitis and they are Gram + but E.Coli which is Gram Negative also can cause Mastitis and you treat with intramammary polymyxin
endotoxin is treated with?
endotoxins produced by G- bact. treat with tetracylines and fluroquinolones since these treat gram negs and dont destroy the cell wall (endotoxins part of cell wall, released if destroyed)
what type of bacteria use pilli?
gram negative (Pilli has lots of "L's" in it...like lipopolysaccharides) (also gram positives wall is too thick for it) (pilli also look like little minus signs)
another name for pili
examples of immune escape
aquisition of virulence factors (4)?
mutation, transformation (entry of free DNA--set the transformers free!), transduction (via bacteriophage aka virus---duck! here comes a virus!), conjugation**(very common...donor gene. PLASMDS. conjugate to plasmidding).
what has outer membrane and periplasmic space?
gram negatives (negatives have outer membrane for pili to attach to )
when is a guarded swab used?
collection from uterus
florescent antibody test?
antibody which fluoresces... if attaches to antigen, positive result will light up under blacklight. can test for antibodies (bruellosis) or antigens (black leg)
capsule is more common in what type of bacteria? example?
mostly gram negative, but positives can too. example is streptococcus pneumoniae or pasturella (capsule wont "slide off" of gram negatives with their possible pili- also gram pos wall too smooth and big)
example of a bacteria using pilli in the intestines?
E. Coli (they also have flagella)
what is e. coli's cultivation (doubling) time?
what is mycobacterium tuberculosis' cultivation (doubling) time?
anaerobic bacteria definition, and examples?
requires NO O2 to grow. Fusobacterium, clostridia, ecoli (facilitative)
microaerobic definition, and examples?
need a small amount of O2 (5%) ex: campylobacter jejuni (smiles in the sun--happy so dont need much)
aerobic definition, and examples?
requires O2 to grow (20%). This is most bacteria.
psychrophilic definition, and examples?
cold-loving (grow at 4*C) ex: listeria, (yersinia enterococlitica)
thermophilic defintion, and example?
heat-loving (grow at 45* C) ex: campylobacter jejuni (smilin' in the sun)
how would you go about with sample collection?
keep refrigerated to slow growth on collection media, don't use dry swabs (moist is what you want), anaerobes must be stored in anaerobic container.
hemolysis is evidenced on what agar? Example of this agar being used on _________?
hemolysis = destroys blood in the BLOOD AGAR. staphylococcus does this. (gram negs and gram positives can be hemolytic, though)
how would you describe MacConkey agar?
SELECTIVE (usually gram negatives but NOT gram positives grow on McC agar. I guess MacConkey like being a negative Nancy, ha.)
how is lactose fermentation indicated?
pink colonies on McC agar
what color can pseudomonas be?
pseudomonas will produce a green colony on McC agar.
what is a catalase test? what does it show?
used to differentiate staph and strep. It is dropping 3% hydrogen peroxide onto a colony and seeing if it bubbles. If it bubbled, it's staph (positive test) [the staph and rod of the great catalase master!]
what makes a bacteria resistant to penicillin? example?
if the bacteria produces beta-lactamase, it will destroy the beta lactam ring in the penicillin and render it useless. example is staph.
what is an agglutination test? example??
serum of animal mixed with suspension of specific killed organisms. will "clot" if positive. example: brucella*
what is a tuberculin test? what type of a test is it? what does it test for?
test for tuberculosis, it's a delayed hypersensitivity test. noteable reaction (swelling, irritation) to test means it's positive.
what is a mallein test? what type of test is it? what does it test for?
it's a delayed hypersensitivity test. injecton into eyelid of horse. It diagnoses glanders' disease in horses. (swollen = positive test)
example of host susceptibility between species?
shipping fever in cattle due to Mannheimia haemolytica does not affect dogs
what causes strangles in a horse?
example of a obligate pathogen
bacillus anthracis (anthrax)
example of an opportunistic pathogen?
E. coli in intestine/urinary tract, or a secondary pathogen moving in on infected area.
exogenous vs endogenous pathogen means what? examples?
exogenous pathogen means infecting agent came from outside source of body. endogenous means from the body itself. Exogenous example = bascillus anthracis from the soil. Endogenous example = gingivitis in dog from commensals (symbiotic bacteria of the mouth)
example of a non-contagious pathogen?
tetanus, or gingivitis
what is a secondary pathogen?
only infects site after something else already has
example and explanation of attachment entry?
E. Coli uses pilli to attach to intestinal mucosa and cause diarrhea. animal doesn't have immunity to pilli, so causes disease. only affects young because adults don't have receptors for the E. Coli.
what are some virulence factors (4)?
pili, non-fimbrial adhesins, capsule, toxins
what bacteria can use entry via ingestion?
salmonella from feed
what bacteria can use entry via skin abrasion or mucosa?
leptospirosis from contaminated water "wiggle into" skin/mucosa
endotoxins are produced by? Examples?
only gram negative bacteria.... examples include E. Coli, and salmonella. "endotoxemia" (endotoxins in blood) is/can be fatal
exotoxins are produced by? examples?
both gram positive and gram negative bacteria.....example- tetanus neurotoxin, cholera toxin, E. Coli enterotoxin, botulism neurotoxin
4 major classifications of antibacterial drugs are?
bactericidal, bacteriostatic, narrow spectrum and broad spectrum
example of bactericidal drug
example of bacteriostatic drug
2 examples of narrow spectrum drugs
bacitracin( gram positive--mess with cell wall), penicillin G (tracing a narrow line around the letter G)
example of broad spectrum drugs
4 major mechanisms of action for antibacterial drugs
inhibition of cell wall synthesis, damage to cell membrane function, inhibition of nucleic acid synthesis or function, inhibition of protein synthesis
most active agent against pseudomonas?
gentamicin (everything is "gentle" on pseudomonas EXCEPT "gentle-mycin") (it is an aminoglycoside)
two most sporicidal agents?
formaldehyde and chlorine dioxide
quantitative test is, example?
gives us a quantity we can use, i.e., minimal inhibitory concentration....(lowest conc. of drug to stop growth of bact.). example is broth dilution method, used to calculate doses for infections
qualitative test is, example?
example is kirby-bauer (disk diffusion) method. place antibiotic disks on plated bacteria. zone of inhibition is measured and compared...see how susceptible bact is to that antibiotic.
major gram positives? (10)
clostridia, actinomyces, bacillus, streptococcus, staphylococcus, nocardia, rhodococcus, lysteria, corneybacterium, dermatophilus, (so...all of the branching ones. staph and strep. the two major spore forming ones. the psychophile, the pleomorphic one. and then the "rotary phone" ) - need listerine after you eat corn
major gram negatives?
E. coli, salmonella, campylobacter, pseudomonas, brucella, leptospira, pasturella, bordetella, mannheimia, haemophilus, (curvy rods, rods, spirals...bipolar is baddd, bleeding is baddd, boarding school sucks, cow disease...)
what two examples of bacteria are not gram positive or negative?
mycobacterium (wall too thick), mycoplasma (no wall)
what would cause a gram positive to appear red/pink like a gram negative?