Mycology Flashcards
What are some key facts surrounding fungi?
- Eukaryotic
- widely distributed in the environment
- can be commensals
- grow aerobically
What are the four main groups of fungi?
- Ascomycetes
- Basidiomycetes
- Zygomycetes
- Deuteromycetes
What is the name of the fungi of most veterinary importance?
Deuteromycetes
(usually only asexual reproduction)
What are the two main morphological forms of fungus?
- Filamentous
- Yeast
3.Some can take on both forms (this is dependent on the environment)
When may a fungus be in its spore phase?
When the fungus is in the environment
with decreased temperatures
More Oxygen and more Nutrients
When may a fungus germinate into yeast?
When in a host, this is where it reproduces through budding
What are two examples of fungi that can change shape/ size in order to survive in the environment?
Dimorphic fungi
* Candida albicans
* Histoplasma
What is a dimorphic fungus?
Switches between Yeast and Filamentous
What are three mechanisms involved in fungal production?
- Tissue invasion (mycosis)
- Toxin Production (mycotoxicosis)
- Induction of hypersensitivity (this is rare in domestic animals)
What are the two types of mycosis that fungi can cause?
- Superficial (mucous membranes + subcut)
- Systemic (usually in the respiratory or GIT)
What are the three types of dermatophytes?
- Zoophillic (obligate pathogens that mainly effect animals and people)
- Anthropophillic (obligate pathogens that only infects humans)
- Geophillic (they occur naturally in the soil with decomposing hair/ feathers)
Where does dermatophysis most commonly invade?
superficial keratinised structures (skin, hair claws)
the transmission is via direct or indirect contact with spores
What are the four most common dermatophytosis (ringworm) fungi?
- Microsporum canis
- Trichophyton mentagrophytes
- T.Verrucosum
- M.gypseum
How long does it take Dermatophytosis spores to germinate on the skin?
They germinate on the skin within 6 hours
What clinical signs will dermatophytosis cause?
- Alopecia
- Dermatitis
- epidermal hyperplasia
- hyperkeratosis
- secondary bacterial infections