intro to mycology Flashcards
what is mycotoxicosis?
intoxication with fungal byproducts that may contaminate feed
-aflatoxins
-ergot alkaloid
what are the predisposing factors to an animal to fungal invasion?
immunosuppression
prolonged antibiotic therapy
traumatized tissue
persistent moisture/poor ventilation
are fungi prokaryotes or eukaryotes?
eukaryotes
what are the basic morphological forms of fungi?
yeast
mold
what are the cell membrane components of fungi?
ergosterol
chitin
what are the different types of budding that yeast have?
encapsulated
germ tubules
pseudohyphae
what type of budding does the yeast crytococcus have?
encapsulated
what type of budding does the yeast Candida albicans have?
germ tubes
pseudohyphae
what are dimorphic fungi?
a type of yeast that is temperature dependent and can switch between yeast and mold
what type of yeast is histoplasma
dimorphic fungi
what are the morphological structures of molds?
multicellular filamentous colony
hypha
mycelium
what are hypha?
long filament or strand of cells +/- septa
what are mycelium
mat of hyphae
is aspergillus septate or nonseptate
septate
is rhizopus, mucor septate or nonseptate
nonseptate
what are the asexual spore types? and what do they have?
rhizopus, mucor
sporangiospores
how are sporangiospores produced?
produced within a sporangium
what are sporangiophores
stalk upon which the sporangium sits
what is conidia and related structures?
open, not enclosed in sporangium
what types of fungi have asexual spores types of conidia?
aspergillus
penicillium
what is a conidiophore
bears the vesicle, metula, and phialide with conidia
what are the two types of conidia
give an example for micro and macro conidia
what is blastoconidia
budding yeast
what is arthroconidia (arthospores)?
barrel-shaped conidia
what type of reproduction do spores have?
asexual reproduction
where are sporangiospores located?
within a sporangium
where are conidium located?
from conidiophore
what are the general fungal disease classified as?
mycoses
mycotoxicoses
hypersensitivities
what does mycoses cause?
granulomas +/- necrosis +/- abscess formation
what does mycotoxicoses cause?
intoxication and tissue damage, not an active infection and not a mycosis
what does hyersensitivites cause?
allergic pneumonitis, etc. may occur but are not classified as mycoses or mycotoxicoses
what are the pathogenicity and disease classifications?
superficial
subcutaneous
opportunistic
systemic
what are the two types of superficial mycoses
ectorthrix and endothrix
what is ectothrix
-fungal attachment to surface of the hair shaft, degrading cuticle
-may fluoresce with wood’s lamp
what is endothrix
-fungal invasion of the hair shaft, cuticle intact
-does not fluoresce with a wood’s lamp
example of superficial infection
example of subcutaneous infection
example of opportunistic infection
example of systemic infection
what are oxygen requirements for most fungi?
obligate aerobes
what are the temperature requirements for fungi?
ambient 25 degrees celsius
+/- body temperature
what substance can inhibit bacterial growth of fungi
sabaroud dextrose
yeast growth requirement
require biochemical +/- molecular ID (MALDI, PCR)
what grows faster, mold or yeast?
yeast
how to ID mold
requires weeks to mature
ID based on structure +/- molecular ID
how would you examine yeast under direct microscope examination
tape preparation
stained tissue
what are specific tests to ID fungi?
immunological tests or molecular methods (PCR)
