Exam 3 Flashcards
Which mycobacterium has a very broad host range, including badgers and brush tail possums?
Mycobacterium bovis
What is the reservoir for Mycobacterium leprae?
armadillo
What is the main host for Mycobacterium lepramurium?
cats
Which mycobacterium is dependent on Mycobactin for growth?
M paratuberculosis
What organism causes Johne’s disease?
M avium susp. paratuberculosis
What can cause a false negative on ELISA when testing for Johne’s disease in the late stages?
anergy
Are mycobacteria gram positive or negative?
gram + (and acid fast +)
Are spirochetes gram negative or positive?
gram -
Which spirochete causes swine dysentery?
Bradyspira hyodysenteriae
T/F B pilosicoli has a synergistic relationship with other anaerobes in the colon.
T
Which organism causes lesions only in the large intestine, creating a sharp demarcation at the ileocecal junction?
Bradyspira
Which organism causes rabbit syphilis?
Treponema paraluis (caniculi)
Papillomatous digital dermatitis is caused by which organism?
Treponema
Other names for papillomatous digital dermatitis (PDD)?
hairy heel warts, strawberry foot disease
Treatments for strawberry foot disease?
spray feet with antibiotic, formaldehyde foot baths
*caution carcinogens
Borrelia burgdorferi causes what?
lyme disease
What organism causes avian borreliosis?
B anserina
outer surface proteins in B. burgdorferi
C -> A in midgut of tick
A -> C in salivary glands of tick
C in mammals in early infection
Which ticks transmit B. burgdorferi?
ixodes scapularis (east US) and ixodes pacificus (west US)
How do you interpret a lyme test?
clinical signs but negative test = retest
no clinical signs but positive test = subclinical
*only treat in endemic areas
Do you always treat for Borrelia burgdorferi?
No, most infections are subclinical
Can give dogs doxy in endemic areas
*vaccine decreases incidence
How would an animal acquire a Leptospira infection?
direct contact with infected urine or water
What is a concern with a leptospira infection in a dog?
chronic kidney disease
To diagnose a leptospira infection in early stages (week 1-2), what should you PCR?
blood
To diagnose a leptospira infection in later stages (week 3-4) what should you PCR?
urine
What type of immunity is most important for a lepto infection?
humoral
Which organism could cause blood tinged milk in a cow?
L. pomona
What does L. borgpetersonni cause in cattle?
reproductive failure due to embryonic death and repeat breeding
*vaccine
How should you collect urine to diagnose Leptospira?
catch urine midstream and give Lasix
Which lepto organisms infect horses?
L. pomona and L. grypptyphosa
T/F Rickettsiales are facultative intracellular and gram +
F: obligate intracellular and gram -
Which organisms are in the family Anaplasmataceae?
anaplasma
ehrlichia
neorickettsia
What cells does anaplasma infect?
myeloid cells, neutrophils, RBC
T/F Anaplasma marginale is reportable.
T
Which tick transmits A. marginale?
Boophilus microplus
Which organism causes undulating febrile disease?
A. marginale
Which cells does A. phagocytophilum infect?
neutrophils and eosinophils
Clinical signs of A. phagocytophilum?
fever (not undulating), leukopenia, splenomegaly
Which cells does A. platys infect?
platelets
What organism causes infectious canine thrombocytopenia?
A. platys
T/F Rickettsiae are motile
F
What causes RMSF?
Rickettsia Rickettsii
What is the first clinical sign for RMSF?
vasculitis (infect endothelial cells)
What can cause RMSF to be fatal in dogs?
severe necrosis in extremities
Are there vaccines for rickettsia?
nope
What is the common name for Coxiella burnetti?
Q fever
Is C burnetti reportable?
yes, bioweapon
What is the main host of C burnetti?
sheep
What is important to remember when treating Q fever?
need an alkalinizing agent to kill in the phagosome
*chloraquine + tetracycline
T/F you can’t distinguish C. psitticai and C. burnetti clinically?
T
Which cells does Ehrlichia canis infect?
WBC; obligate intracellular
What causes canine monocytic ehrlichiosis?
E. canis
What does E. chaffeensis cause?
human monocytic ehrlichiosis
What does E. ewingii cause?
canine granylocytic ehrliciosis
What causes African heartwater?
E. ruminatum
Clinical signs of african heartwater?
capillary damage -> edema
damage to cerebrocortical capillaries = neuro signs
fever
Important diseases of Neorickettsia:
Salmon poisoning : N salmincola
Potomac Horse Fever
Do mollicutes have a cell wall?
no
What do non-hemotrophic mollicutes look like in culture?
fried eggs
What causes avian mycoplasmosis?
M. galliseptican *reportable
What does M. synoviae cause?
synovitis = lameness, reduced growth
sternal bursitis in turkeys
M meleagridis and M iowae in turkeys
airsacculitis, skeletal deformities, decreased growth, decreased egg hatchability
What causes contagious bovine pleuropnemonia?
Mycoplasma mycoides subsp mycoides (small colony variant)
*reportable
What gross lesions does CBPP cause?
microabscesses in lung tissue
Which mycoplasma cause mastitis?
M bovis, M californicum, M canadense
What causes contagious caprine pleuropneumonia?
M capricolum subsp capripneumoniae
What causes contagious agalactia of sheep and goats?
M agalactiae and M putrefaciens
What causes porcine enzootic pneumonia?
M hyopneumoniae
What clinical signs are caused by M hyorhinis?
lameness, arthritis, polyserositis
Which mycoplasma infect horses?
M felis -> pleuritis
M equirhinitis -> respiratory disease
Which mycoplasma infect cats?
M gatae
M felis
Which mycoplasma infect dogs?
M canis
M cynos
Which mycoplama infects mice and rats?
M pulmonus
Is there a vaccine for CBPP?
Yes, live attenutated used in enzootic areas
What are the clinical signs of hemotrophic mollicutes?
hemolytic anemia, icterus, splenomegaly, bone marrow hyperplasia
What causes feline infectious anemia?
M haemofelis
*co infection with FIV/FeLV
S shaped or gull-winged in pairs
campylobacter
Which organisms cause food gastroenteritis in humans?
C jejuni and C coli
How do you get C jejuni or C coli?
undercooked poultry, unpasteurized milk, contaminated water
What is the toxin produced in the genus Campylobacter?
CDT
What is the predilection site for C fetus venerealis?
preputial crypts of bulls
Predilection site for C fetus fetus?
intestines, gall bladder of ruminants
Signs of bovine genital campylobacteriosis?
anasarca, metritis with grayish brown exudate
Which organism causes donut lesions in fetal liver?
Campylobacter fetus susp fetus and C jejuni
What organism can be found in 50% chickens ceca?
C jejuni
Can you use tetracycline for campylobacter infections in sheep and goats?
No, there is resistance -> use Tilmicosin
T/F there is no vaccine for C jejuni
T
T/F arcobacter can survive lower temps than campylobacter
T
What does urease do as a virulence factor for Helicobacter?
increases the pH of the stomach making the environment more favorable for the bacteria
Which organisms produce CDT ?
campylobacter and helicobacter
What causes porcine proliferative enteropathy?
Lawsonia intracellularis
T/F pigs can be infected with lawsonia without normal flora?
F: interaction with normal flora required for disease
T/F Chlamydia RB is metabolically active and infective
F: metabolically active but non-infective -> EB is infective
What does chlamydia abortus cause?
abortion in sheep and goats in a cyclic pattern
What does chlamydia felis cause?
conjunctivitis in kittens (also infects iguanas)
Which animals does chlamydia pneumoniae infect?
horses and koalas (mostly asymptomatic)
Which chlamydia infects birds?
C. psittaci
Clinical signs of C. psittaci?
yellow droppings, lethargy, respiratory distress, trembling in ducks and decreased egg production
How long do you treat birds infected with C. psittaci?
45 days -> still often die
Are fungi prokaryotic or eukaryotic?
eukaryotic
T/F fungi are anaerobic
false, most are aerobic
What is the unicellular form of fungus?
yeast
What are the multicellular forms of fungus?
molds or mushrooms
What do you call yeast in chains?
pseudohyphae
Molds that have cross walls are…
septate
Molds that have dark pigment are called?
dermatiaceous
T/F dimorphic fungi are yeasts at room temperature and mycelial in tissue
F: yeast in tissue and mycelial at room temperature
T/F fungi mostly reproduce by asexual reproduction
T
sporulation
hyphae fragmentation
budding of yeast
What is important about griseofulvin for treating fungal infections?
teratogen
T/F if a Woods lamp doesn’t detect dermatophytes, the animal doesn’t have ringworm
F
ringworm in dogs
Microsporum canis
Which dermatophyte is cigar shaped?
Trichophyton
T/F in the parasitic state only hyphae and spores (arthroconidia) are seen
T: you won’t see macroconidia
What can you add to a skin scrape of ringworm to improve visualization?
KOH, ink
What causes ringworm in cattle?
Trichophyton verrucosum (calves)
Ringworm in horses ?
T equinum, M equinum
Which animal does microsporum nanum infect?
pigs
What causes avian ringworm?
Microsporum gallinae (favus)
What do colonies of Candida albicans look like?
white and shiny, beer smell
What causes terry-toweling or sour crop in chickens?
Candida albicans
The “germ tube” formation is characteristic of which fungus?
Candida albicans
Which fungus has a large mucoid polysaccharide capsule?
Cryptococcus neoformans
Where are serotypes B and C of C neoformans found?
Eucalyptus trees and gum trees
Which species is infected by Cryptococcus neoformans?
Cats -> rhinitis, lesions on face
What can Malassezia pachydermatitis cause?
otitis, seborrheic dermatitis
Which fungus has peanut shaped yeast?
Malassezia
What causes rose handler’s disease?
Sporothrix schenkii
Important host for S schenkii?
cats
What does S schenkii look like microscopically? In culture?
cigar shaped, colonies are white to cream with wrinkled aerial hyphae
Can S schenkii cause disseminated disease?
Yes, in immunosuppressed dogs and any cats
Where is blastomyces dermatitidis found in the US?
east
Where are the lesions of B dermatitidis found?
primary: lungs
secondary: skin and other organs
Colony morphology of B dermatitidis?
white cottony aerial hyphae
T/F Blastomyces have narrow buds?
F: broad based buds!
Which animal is most affected by blastomyces?
hunting dogs
What causes “valley fever”?
coccidioides immitis
Where do you find coccidioides immitis?
southwestern US
Where are lesions of coccidioides immitis?
primary: lungs
secondary: bones
What is the microscopic appearance of coccidioides immitis?
barrel shaped spores in chains
Where is histoplasma found?
Mississippi and Ohio River Valleys (overlaps with blastomyces)
How can you distinguish histoplasma from blastomyces?
histoplasma are small budding yeast cells, found intracellularly in phagocytes
Which breeds of dogs are most susceptible to histoplasma capsulatum var capsulatum?
pointing breeds, weims, brittany spaniels
What causes epizootic lymphangitis?
histoplasma capsulatum var farciminosum
aka african horse farcy or pseudoglanders
Where do you find lesions of african horse farcy?
on the skin, neck and legs mostly, tracking along lymphatics
What do colonies of histoplasma capsulatum var farciminosum look like?
oatmeal cookies!
