Lecture 1: Introduction to Veterinary Mycology

Question 1

What is mycotoxicosis

Answer 1

Intoxication with fungal byproducts that may contaminate feed

Question 2

Alfatoxins and ergot alkaloid are examples of ___

Answer 2

Mycotoxins

Question 3

What are the 3 phyla of fungi with veterinary importance

Answer 3

1. Ascomycota
2. Basidomycota
3. Zygomycota

Question 4

What predisposes an animal to fungal invasion

Answer 4

1. Immunosuppression
2. Prolonged antibiotic therapy
3. Traumatized tissue
4. Persistent moisture/poor ventilation

Question 5

T or F: fungi are eukaryotes

Answer 5

True

Question 6

What are the 2 basic morphological forms of fungi

Answer 6

1. Yeast- round to oval cell often with budding cells
2. Mold- filamentous, multicellular body organisms

Question 7

Identify which is yeast vs mold

Answer 7

left: yeast
Right: mold

Question 8

What are 2 important cell membrane components of fungi

Answer 8

1. Ergosterol
2. Chitin

Question 9

What is the predominant sterol in cell membrane of fungi

Answer 9

Ergosterol

Question 10

What drugs target the Ergosterol of fungi

Answer 10

Amphotericin B and azoles

Question 11

What is chitin

Answer 11

Polysaccharide providing cell wall rigidity

Question 12

What specific fungal structure does the yeast cryptococcus have

Answer 12

Encapsulated

Question 13

What specific fungal structure does the yeast Candida albicans

Answer 13

Germ tubes as well as pseudohyphae

Question 14

What are dimorphic fungi and what is an example

Answer 14

Temperature dependent switch between yeast (37 C) and mold (25 C)

Ex: histoplasma

Question 15

Identify the fungal yeast structures 1-3 and provide examples of yeasts that have those structures

Answer 15

1. Encapsulated (ex: cryptococcus)
2. Germ tubes (ex: Candida albicans)
3. Pseudohyphae (ex: Candida albicans)

Question 16

Based on the morphology, what type of yeast is this

Answer 16

cryptococcus

Question 17

Based on the morphology, what type of yeast is this

Answer 17

candida

Question 18

What are hyphae

Answer 18

Long filament or strand of cells +/- septa

Question 19

What is a mycelium

Answer 19

Mat of hyphae

Question 20

Is aspergillus septate or non-septate

Answer 20

Septate

Question 21

Is rhizopus and mucor septate or non-septate

Answer 21

Non-septate

Question 22

What are sporangiospores

Answer 22

An asexual spore type produced within a sporangium

Question 23

What is a sporangiphore

Answer 23

Stalk upon which the sporangium sits

Question 24

Label the fungal structures 1-3

Answer 24

1. Sporangia/um
2. Sporangiophore
3. sporiangiospores

Question 25

What are conidia

Answer 25

An asexual spore type that is open and not enclosed in a sporangium

Question 26

What is a conidiophore

Answer 26

Bears the vesicle, metula and Philade with conidia

Question 27

What type of spore type is this

Answer 27

conidia

Question 28

What type of spore type is this

Answer 28

sporangiospore

Question 29

Identify 1-5

Answer 29

1. Vesicle 2. Conidiophore 3. Conidia 4. Phialide 5. Hyphae

Question 30

What is this

Answer 30

aspergillus

Question 31

What are macroconida

Answer 31

Large conidia with identifiable structures

Question 32

What are microconidia

Answer 32

Small conidia, less specific

Question 33

micro or macro conidia

Answer 33

Micro

Question 34

Micro or macro conidia

Answer 34

macro

Question 35

What this

Answer 35

microsporum

Question 36

What this

Answer 36

Trichophyton

Question 37

What are blastoconidia/ blastospores

Answer 37

Budding yeast

Question 38

What type of conidia is this

Answer 38

Blastoconidia/ blastospores

Question 39

What type of conidia is this

Answer 39

arthroconidia

Question 40

What type of conidia does coccidiodes immitis have

Answer 40

Arthroconidia

Question 41

What are the 2 ways for spores to undergo asexual reproduction

Answer 41

1. Sporangiospores- within sporangium 2. Conidia- from conidiophore

Question 42

What classifies a fungal disease as Mycoses

Answer 42

Granulomas +/- necrosis +/- abscess formation

Question 43

What classifies a fungal disease as mycotoxicoses

Answer 43

Intoxication and tissue damage, not an active infection and not a mycosis

Question 44

What classifies a fungal disease as a hypersensitivity

Answer 44

Allergic pneumonitis, etc. may occur but are not classified as mycoses or mycotoxicoses

Question 45

What classifies as fungal disease as superficial. what are some examples

Answer 45

Typically involved skin, hair, nails (ex: microsporum and other dermatophytes)

Question 46

What classifies a fungal disease as subcutaneous. what are some examples

Answer 46

Deep dermal, often resulting from trauma (Ex: sporothrix and mycetomas)

Question 47

What classifies a fungal disease as opportunistic. what are some examples

Answer 47

Seen in immunocompromised patients (ex: mucocutaneous candidiasis, cryptococcosis)

Question 48

What classifies a fungal disease as systemic/endemic. what are some examples

Answer 48

Severe, often regionally distributed (ex: coccidiodes, blastomyces, histoplasma)

Question 49

What is an endothrix infection

Answer 49

Fungal invasionto the surface of the hair shaft, intact cuticle

Question 50

What is an ectothrix infection

Answer 50

Fungal attachment of hair shaft, cuticle degrading

Question 51

Which fluoresces under Wood’s lamp: endothrix or ectothrix

Answer 51

Ectothrix

Question 52

Endothrix and ectothrix infections are classified as what type of fungal disease

Answer 52

Superficial mycoses

Question 53

Most fungi are obligate ___

Answer 53

Aerobes

Question 54

What are the temperature requirements for fungi to grow

Answer 54

Ambient (25 C), +/- body temperature

Question 55

Most fungi can handle high ___conditions and pH < __

Answer 55

Osmotic, <5

Question 56

What is a common fungal media that inhibits bacterial growth

Answer 56

Sabaroud dextrose

Question 57

Which grows faster: yeast or mold

Answer 57

Yeast

Question 58

What is required to ID yeast

Answer 58

Biochemical +/- molecular ID (MALDI, PCR)

Question 59

What is required to ID mold

Answer 59

Based on structure +/- molecular ID

Question 60

What are some ways to exam yeast or mold under microscope

Answer 60

1. Tape preparation 2. Stained tissue

Question 61

What is used for tape preparation

Answer 61

Lactophenol cotton blue

Question 62

What tissue stains can be used on mold and yeasts

Answer 62

PAS, GMS