Labs 9 - 11 Review: 2011
LAB 9a/b: Skin, Wounds + Body Openings
Concept of “Super-Organism” : animal and microbiome
Otitis Externa in Dogs Malassezia pachydermatis
P. aeruginosa
Proteus mirabilis
E. coli
S. intermedius Group
Wound Infections – Ruminants – A. pyogenes Dog bite wounds – Pasteurella spp., Obligate anaerobes, others
Cat bite wounds – Pasteurella multocida, Moraxella spp
LAB 9a/b: Skin, Wounds + Body Openings
Exercise 1.
Lab 9a: Skin, Wounds, …
Exer. 2: Sheep, exudative dermatitis
P. aeruginosa
BA: large, metallic sheen, hemolytic,
NLF on MAC, Ox +ve
Green wool or fleece rot – moisture/feces/blow flies (wool strike)
MHA shows pigment
Lab 9a: Skin, Wounds ..
Exer. 3: Cow - extensive dermatitis on the dorsal aspects of the face and body.
“paintbrush” scabs
Gram stain from scab impression smear
Rail-road/ stack of coins
Can you make a diagnosis with information provided ?
What organism?
Vaccines? Penicillin?
Lab 9a: Demo 1a/b – Pinkeye/IBK
BA – β-hemolytic, No Mac
Gram -ve, coccobacillus
Mucous membranes
(conjunctiva)
Intervention
Vaccination – several
Face fly (M. autumnalis)
Abx – Oxytetracycline
Optic corticosteroids
Zoonotic
Lab 9a/b: Skin, Wounds, …
Demo 1: K9 Post-op infection
Most likely Genus and species?
Demo 2: Equine – spastic paralysis
Sawhorse-stance , tremors
puncture wound exudate
Aspirate direct smear and G-stain
- Gram-positive
- drumstick/tennis racket morphology
Antitoxin, Vaccines?
Lab 9b: Clostridium +
C. perfringens
C. septicum
Lab 10: Mycoplasmas/Haemoplasmas
No peptidoglycan, highly pleomorphic
Specialized media
10-20 % serum – cholesterols
Hayflicks, Freys, Friis
“Fried Egg”, microcolonies
Haemoplasma’s – no culture Mycoplasma haemofelis
Serology and/or PCR
Mycoplasma Genus/Species
Disk Growth Inhibition (Digitonin)
- Cholesterol Genus
Serum Plate Agglutination (serology)
- species
M. gallisepticum: CRD (Air Sacculitis) Chickens, IS in Turkeys management
M. bovis Caseonecrotic bronchopneumonia in feedlot:
arthritis/tenosynovitis; contagious agalactia mastitis dairy
Pre-feedlot (vaccines, stress); feedlot (mixing, quarantine, Abx)
M. haemofelis : Feline Infectious Anemia Flea control, Doxycycline
M. hyopneumoniae : Enzootic pneumonia in swine (MPS) Management, cough-score, vaccines,
Lab 10: Mycoplasmas/Haemoplasmas: Q/A
Lab 11: Mycology – Major Clinical Mycoses
Cutaneous
Dermatophytes, Malassezia spp.
Subcutaneous
Sporothrix schenckii
Systemic
Thermally Dimorphics
True Yeast – Cryptococcus spp.
Opportunistic
Candida spp., Aspergillosis, Mucormycoses
Fungal-like
Algae
Mycological Examination of tissue
Wet Mount - 10-20% KOH/LPCB
Exudates, TTA – India-ink, H and E, Giemsa
Impression smears – H and E, PAS
Histological/Biopsy - PAS, Methenamine
Silver, H and E
Culture – BHI +, Sabourauds
Lab 11: Mycology – General Examination
VII. A. Zygomycosis
1. Abortion case - Culture
Mucor spp.
Microscopic
Aseptate hyphae
Sporangium
Rhizoids
Silver stained placenta
Non-parallel, 10-25 uM
Typically aseptate
Hyphal bulges
Aspergillus fumigatus
Demo 3. Dog: chronic sinusitis
Culture
Microscopic morphology
Septate hyphae
Vesicle
Conidiospores
Nasal Aspergillosis
Radiology, Rhinoscopy
Guttural Pouch Mycosis
Brooder pneumonia
Abortion in ruminants
Dermatophytosis
Demo 6. Direct Examination
10 % KOH
Ectothrix arthroconidia/spores
Culture - SAB
M. canis (Cats, Dogs, Humans)
M. gypseum
T. mentagrophytes
T. verrucosum
VII. B. Yeasts + Thermals
Demo 1a Candida albicans
Malassezia pachydermatis
“footprint”
Bigger than Staph/Strep
Otitis externa,
Seborrheic dermatitis
Malassezia
Demo 1b. Canis Otitis Externa
Demo 1c. Cryptococcosis
Cryptococcus neoformans
Encephalitis: PAS
2. Thermally Dimorphic Fungi
Histoplasma capsulatum
Endemic Miss., Ohio, St. Lawrence
Bat/bird feces
Intracellular Yeast
Mold phase (tuberculate chlamydospores)
Blastomyces dermatitidis
Endemic as per H. capsulatum
Terminal chlamydospore (lollypop)
Histo – 37 oC
Blasto – 37 oC
Lollipop Chlamydospores
Thermally Dimorphic: Biphasic
Coccidioides immitis
S.W. U.S.
37 oC
Endosporangium “Spherule”
Mold/Environmental Phase
Barrel shaped arthrospores
Barrel arthrospores
Spherule – 37 oC
SubQ Thermally Dimorphic
Sporothrix schenckii Ulcerative lymphangitis
○ Horses, cats, cattle, people
Mold phase (septate)
○ Microconidia (flowerettes)
37 oC – Yeast phase ○ Cigar bodies (cats)
Demo C. Algae: Prototheca spp
Mastitis case: