Large Animal Infectious Diseases Flashcards
What are the three primary presentations of diseased caused by staphylococcus in large animals?
- Impetigo, 2. Mammillitis, 3. Folliculitis/Furunculosis
Appearance of dermatophilosis on cytology
branching hyphae - railroad tracks, branch in both longitudinal and transverse directions, forming packets of coccoid cells –> coccoid cells break off to form flagellated zoospores (infectious component)
What disease is caused by swine papillomavirus?
transmissible genital papilloma (can also occur on face/snout)
What species of atypical mycobacteria (nontuberculous mycobacteria) have been isolated from large animals?
M. kansaii, M. ulcerans
Causative agent of lumpy jaw - oral commensal
Actinomyces bovis
What plant contains immunosuppressive and mutagenic compounds that has been associated with BPV-4 infection?
bracken fern
What special considerations need to be observed in cultures of Trichophyton verrucosum
Need to add thiamine to growth medium, some strains need inositol added as well –> enhances production of microconidia; needs to be incubated at 37 degrees C
What is the causative agent of caseous lymphadenitis in small ruminants and cattle?
Corynebacterium pseudotuberculosis
What are the clinical presentations of papillomavirus infection in goats?
Teat/sudder - Saanen does; Face,head, shoulders, forelegs
Clinical signs of orf (contagious viral pustular dermatitis, contagious ecthyma)?
vesicles, erythema, pustules –> crusts and scarring; lesions on lips/oral mucosa, coronary bands, teats
T/F: Dermatophilosis is zoonotic.
TRUE
What animasl are susceptible to infection with orf (contagious viral pustular dermatitis, contagious ecthyma)?
Sheep, goats, camelids (NOT cattle)
T/F: Orf (contagious viral pustular dermatitis) is zoonotic.
TRUE
What genotypes of bovine papillomavirus have been isolated from feline sarcoids?
BPV - 14
Actinobacillus lignieresii: Gram + or -? Morphology?
Gram NEGATIVE coccobacillus or rod
What is different about the hyphae of Pythiosis than Zygomycosis?
Pythium have non-septate hyphae
T/F: Penicillin G is the first-line treatment of choice for exudative epidermitis in swine.
False - high rate of antimicrobial resistance reported in Staph hyicus strains – C&S needed
Most common causes of infectious nodular swellings in horses
Corynebacterium pseudotuberculosis
Habronema spp.
Sporotrichosis
Clinical signs of exudative epidermitis in pigs
discolored skin and scale in axillae and groin, widespread greasy brown exudate, oral and heel/coronary band erosions and ulcerations; can have positive Nikolsky sign; pain, not pruritic, febrile
What is the clinical presentation of papillomavirus infection in camelids?
mucocutaneous fibropapilloma
Cytological characteristics of Corynebacterium pseudotuberculosis
INTRACELLULAR!, pleomorphic bacterium, taking on coccoid, club, or rod shapes; Gram-POSITIVE facultative anaerobe
What is a koilocyte?
keratinocyte with shrunken, dark nucleus surrounded by a halo with clumped keratohyalin granules (characteristic of papillomavirus infection)
What are the clinical presentations of papillomavirus infection in sheep?
filiform squamous papilloma (frond-like lesions on fetlocks or scrotum of young animals); fibropapillomas on face, legs, teats of adult animals
T/F: Erysipelothrix rhusiopathiae is zoonotic.
TRUE
What genotypes of bovine papillomavirus have been isolated from equine sarcoids?
BPV -1, 2
Erysipelothrix rhusiopathiae: Gram positive or negative? Aerobic or anaerobic? Morphology?
gram-POSITIVE pleomorphic ROD, facultative anaerobe
What is the causative agent of contagious viral pustular dermatitis (aka orf, contagious ecthyma)?
Parapoxvirus ovis
T/F: All types of bovine papillomavirus in cattle will spontaneously regress.
False - BPV-3 “atypical warts” do not regress, BPV-5 “rice grain” warts do not regress, BPV-6 conical to branch-like warts on teats do not regress
Histopathological findings with orf (contagious viral pustular dermatitis, contagious ecthyma)?
epithelial hyperpigmentation, ballooning degeneration of keratinocytes (intracellular swelling), intracytoplasmic pox-viral inclusions
Histopathological appearance of dermatophilosis
neutrophilic luminal folliculitis and furunculosis with lamellar crusts
What are the 3 regions of the genome of papillomaviruses?
E (early), L (late), Long codon (or control) region (LCR)
What are the 4 isoforms of desmogleins and where are they found?
Dsg 1 & 3: Stratified squamous epithelia; Dsg 2: all tissues with desmosomes including simple epithelia and myocardium; Dsg 4: primarily hair follicles
What are the main staph species found on large animals?
Staph aureus and Staph hyicus
What functions do the early genes of the papillomavirus genomes encode for?
E1: viral DNA replication; E2: viral DNA replication; E3: infected cell immune response; E4: cytokeratin disruption to facilitate viral release; E5: down regulates MHC-1, interrupts gap junctions, PDGF interactions; E6: p53 down regulation, actin cytoskeleton disruption; E7: cell transformation, pRb phosphorylation
What is the causative agent of exudative epidermitis in pigs (aka Greasy Pig Disease)
Staph hyicus
What clinical lesions do BPV-1,2 form in cattle?
fibropapillomas; BPV-1 = teats, BPV -2 = head and neck
Most common causes of erosions and ulcerations in horses and ruminants
Dermatophilus congolensis
- Habronema spp. (horses)
- Viral diseases (ruminants - infectious bovine rhinotracheitis, vesicular stomatitis, bovine herpes mammillitis)
Causative agent of “wooden tongue” - pyogranulomatous glossitis
Actinobacillus lignieresii
What is the most common species of dermatophytes to be found in swine?
Nanizzia nana (formerly microsporum nanum)
Most common causes of infectious nodular swellings in ruminants
Corynebacterium pseudotuberculosis Hypoderma species (warbles) Sporotrichosis Actinobacillosis Actinomycosis
T/F: Classic diamond skin disease is due to an acute infection with Erysipelothrix rhusiopathiae.
False - is a subacute presentation; acute disease has fever, depression, anorexia, lameness, and purpural skin discoloration of the jowls, abdomen, pinnae, legs
What type of immunity results in regression of papillomavirus infections?
cell-mediated
What do the genes of the LCR region encode for in the papillomavirus genome?
origin of replication, multiple transcription factor binding sites
What do the genes of the late region encode for in the papillomavirus genome?
structural proteins; L1: major capsid protein, promotes viral infection by binding heparin sulfate; L2: virion assembly, virus infection, viral genome segregation
What is the appearance of Nanizzia nana on culture?
flat cream to buff colored with powdery surface and reddish-orange to brown underside; produce numerous macroconidia – oval structures with 1-3 cells
What is the most common species of dermatophytes to be found in ruminants and camelids?
Trichophyton verrucosum
