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VPM 201

Veterinary Bacteriology and Mycology

Laboratory Review-Pt 2: 2010

Lab 6a/b: Respiratory Infections

P. multocida

Exercise 1. feline pneumonia, Abx (Clavamox) unresponsive : TTA: Enterobacter

cloacae: No pix, LF, motile, Indole/Urease –ve, Citrate +ve

Exercise 2. BRDC – mixed culture Mh/Pm . Ex. 3 . Cat bite wound : P. multocida

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Lab 6b: Respiratory Infections

A. pleuropneumoniae

Morse code Demo 4: Kennel cough

“honking cough” ITB

Lab 7: Canis Otitis Externa

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Lab 7. Felis with a felis x 2

Staph. albus !?

- 12 week old cat new in household

- Came from short stay at SPCA

- About week ago one eye was “tearing”

- Now both affected , muco-purulent

Chlamydophila felis

Giemsa stain

EB

Conjunctival epithelial cell

Lab 7: Pinkeye

• BA – β-hemolytic

• No MAC growth

• Gram -ve, coccobacillus

• Oxidase +ve, nonmotile

• Intervention

– Vaccination – several

– Face fly (M. autumnalis)

– Abx – Oxytetracycline

– Optic corticosteroids

– Zoonotic

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Lab 8a/b: Urinary Tract Infections

Inte rpre tation of Quantitative Urine Culture Results in Dogs

Method ofCollection

Infection(cfu/mL)

Equivocal (cfu/mL) Contamination(cfu/mL

Cystocentesis >1,000 100-1,000 <100

Catheterization >10,000 (D) 1,000-10,000 (D) <1,000 (D)

Voided (Midstream) >100,000 (C) 10,000 - 100,000 (C) <10,000 (C)

cfu = colony form ing units ( ie. the number of bacteria)

Note: most UTI’s caused by single bacter ial species and are not the result of mixed

infections.

UTI = urethritis, cystitis, ureteritis, pyelonephritis

Lab 8a/b: UTI • Dog UTI. Cystocentesis plated on BA/Mac.

No Mac Growth. I.d. – BA – double zone, Catalase positive, Coag Positive:

gram-positive cocci

• S. pseudintermedius

– Quantitative plating: Cysto > 1,000 CFU/mL

– Counts/purity

• Radiology/Ultrasonography • Other Agents of K9 UTI

– E. coli, P. mirabilis, K. pneumoniae, Strep/Enterococci spp., P. aeruginosa

– Cats different – Staph felis case ,

• Goal of UTI Abx: 3 – 5 x MIC

– If Baytril MIC is 0.5 ug/mL then need to be able to achieve 2.5 ug/mL in bladder (pharm/tox)

1 bug / 10 HPF = 105

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Morse code

Lab 8a: UTI: Demo’s

• Kidney of 4-day old foal. P.M. shows micro-abscess in kidneys.

• A. equuli Sleepy Foal Disease

• BA: viscid, +/- hemolysis

• LF on MAC

• Cow with UTI: C renale

– Coryneform; Palisade, acute angles, Urease +ve

• Recall: Enterococcus spp.

• Actinobaculum suis

Lab 9/10: Clostridium/Mycoplasmas

• No peptidoglycan, highly pleomorphic

• Colony: “Fried Egg” , microcolonies

• Specialized media (10-20 % serum – cholesterols)

– Hayflicks, Freys, Friis

• Disk Growth Inhibition test(s)

– Digitonin sensitivity (Biochemical) genera

– Growth Inhibition with Specific Antisera - species

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Mycoplasma Genus/Species

Q/A

• M. gallisepticum: CRD (Air Sacculitis) Chickens, IS in Turkeys

• M. bovis

– Caseonecrotic bronchopneumonia in feedlot: arthritis/tenosynovitis ; contagious agalactia mastitis dairy

• M. felis

– Conjunctivitis, Feline Resp. Dis. Complex, polyarthritis in immunodeficient cats

– Resp. disease in immunocompromised humans and foals

• M. hyopneumoniae : Enzootic pneumonia in swine

• M. haemofelis : Feline Infectious Anemia

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Lab 10: Misc. Demo cases

• A cow presents with extensive dermatitis on the dorsal aspects of the face and body. Large scabs “paintbrush” were removed from the lesions. A Gram-stain prepared from the scab material is provided.

• Can you make a diagnosis with information provided ? Why?

• If yes, what organism might this be?

• Vaccines? Penicillin?

Lab 10: Demo Cases

• 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

• Equine (stiff, sawhorse stance hyperexcitable) – puncture wound exudate

– Gram positive –

– drumstick/tennis racket morphology

– Vaccines?

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Lab 11: Mycology

• Mycological Examination of tissue

• Wet Mount - 10-20% KOH

• Stains - Giemsa, PAS, Methenamine Silver, India

ink, LPCB

• Culture – BHI +, Sabourauds

• Dermatophytosis, Aspergillosis, Zygomycosis

• Yeast

• Dimorphic Fungi

Zygomycetes

• Culture

– Mucor spp.

• Microscopic

– Aseptate hyphae

– Sporangium

– Rhizoids

• Silver stained placenta

– Brown hyphae

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Aspergillus fumigatus

• Dog: chronic sinusitis

• Culture

• Microscopic morphology

– Septate hyphae

– Vesicle

– Conidiospores

• Nasal Aspergillosis

– Radiology, Rhinoscopy

• Guttural Pouch Mycosis

• Brooder pneumonia

• Abortion in ruminants

Dermatophytes

• Cultures

– M. canis (Cats)

– M. gypseum

– T. mentagrophytes

– T. verrucosum

• Microscopic

• KOH/PAS

– Ectothrix arthrospores

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Yeasts

• Candida albicans

• Malassezia pachydermatis

– “footprint”, lipophilic

– Bigger than Staph/Strep

– Otitis externa,

– Seborrheiac dermatitis

Malassezia

Systemic Mycoses

• Cryptococcus neoformans

Encephalitis: PAS

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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

• Coccidioides immitis

• S.W. U.S.

• 37 oC “Spherule” phase

• Mold Phase

– Barrel shaped arthrospores

Thermally Dimorphic

Barrel arthrospores

Spherule – 37 oC

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• Sporothrix schenckii

– Ulcerative lymphangitis

• Horses, cats, cattle, people

– Mold phase (septate)

• Microconidia (flowerettes)

– Body Temp.

• Cigar bodies (cats)

• Plants and mastitis?

SubQ Thermally Dimorphic + Algae