Term
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Definition
Uni or multicellular organisms
Aerobic eukaryotes
Defined nuclei
Cell walls of carbohydrate and chitin, ergosterol in plasma membrane
Saprophytic or parasitic
Sexual and asexual reproduction
Asexual spores by mitosis – infectious forms of hyphal fungi |
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Term
| Lab Diagnosis of Fungal Infection |
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Definition
Clinical specimens
Direct microscopy – KOH preps, calcofluor white, Gram stain on colonies, Giemsa
Culture – Sabarauds dextrose agar, chromagar, specialised agars - days or weeks
Identification by morphology of hyphae, production of spores
PCR
Histology of tissue in invasive disease – silver stains |
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Term
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Definition
Unicellular organisms that reproduce by budding - grow on skin, mucous surfaces and in the body
Some times daughter cells may not detach themselves - the result is a pseudohyphae (pseudo and true hyphae – Candida albicans) |
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Term
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Definition
Filamentous hyphal fungi
Multicellular, multinucleate
Basic unit is the hyphae, a long thin filament
Hyphae branch and cross link to forma mat (mycelium)
Growth occurs at hyphal tip
Hyphae may be divided by cross-walls (septa) into uninuclear units
Non septate hyphae: coenocytic
Septa contain pore. All cytoplasm is connected. |
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Term
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Definition
| Organisms that can produce both hyphae and yeast-like forms. Moulds in the environment, yeast in animal tissue – yeast is the pathogenic form |
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Term
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Definition
Gram positive. Yeasts, pseudohyphae.
Grows at 37C on Sabouraud’s dextrose agar/Chromogenic agar
Creamy white 2mm colonies |
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Term
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Definition
Cattle - Mycotic abortion, Rumenal infections, Mastitis
Pigs - dermatitis
Dogs - chronic enteritis and dermatitis, vaginitis/vulvitis in diabetes
Birds - crop infections, enteritis
Man – mucosal and systemic infection |
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Term
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Definition
Yeast
Bottle shaped
Malassezia pachydermatis
Grows on Sabouraud’s dextrose agar at 37C
Lipase, urease
Otitis externa, Dermatitis |
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Term
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Definition
Yeast
C. neoformans, C. grubii, C gattii
Inhalation of yeast cells in dust – pigeon faeces
Opportunistic infections – defective cell mediated immunity - meningitis
Nasal cavity of cats with chronic rhinitis
Nasal, cutaneous, neural and ocular disease in cats
Mucilaginous capsule – india ink stain – virulence factor
20 m total |
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Term
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Definition
Microsporum, Trichophyton sp.
Digest keratin – infect skin, hair and nails |
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Term
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Definition
mould
RINGWORM
Dermatophyte
M. canis
M. gypseum
M. nanum
May fluoresce under Wood’s light |
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Term
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Definition
mould
RINGWORM
Dermatophyte
Spiral hyphae
No fluorescence
T. verrucosum - cattle
T. mentagrophytes - dog, horse
T. equinum - horse
T. gallinae - fowl |
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Term
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Definition
mould
A. fumigatus - on food stuff
Mainly respiratory infection |
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Term
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Definition
Endemic in Mississippi and Ohio river valleys
Man, Dogs and cats
Impaired CMI
Granulomas in lungs
Infection of macrophages |
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Term
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Definition
Broad hyphae non-septate
Asexual spores in a sporangium
Sexual spores oospores or zygospores
Mucor, Rhizopus, Absidia, Saprolegnia
Infection uncommon in healthy immunocompetent animals
Immunodeficiency, steroids, antibiotics
Abortion in cattle
Rumenitis |
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Term
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Definition
| Secondary metabolites of fungal species in crops, pasture or stored feed |
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Term
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Definition
| Difuranocoumarins – Aspergillus sp. Aflatoxicosis – absorption from GI tract, metabolised by liver to toxic product – carcinogenic |
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Term
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Definition
| Ergopeptide alkaliods – Claviceps purpurea – domestic animals and humans – seed heads of grasses and cereals – ergotamine and ergometrine – affect nerves supplying arteriolar smooth muscles |
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Term
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Definition
| Zearalenone – potent non steroidal oestrogen produced by Fusarium sp. – maize other cereals – reproductive problems in cattle and sheep |
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