C19 pt 2 Flashcards
Bovine papular stomatitis
- genus, family, relative
- clinical significance
- age, signalment
- signs
- lesions
- humans
- differentials
o Genus Parapoxvirus, Family Poxviridae, relative
of pseudocowpox
o Usually not clinically significant but must rule out
similar diseases
o Often seen in calves with failure of passive
transfer or immunosuppressed adults o Does not form vesicles
o Individual lesions heal within a week o Potentially zoonotic
o Differentials: BVD, FMD, infectious bovine rhinotracheitis
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- Round, erythematous papules on nose and mouth
- Elevated at first but become necrotic and may slough to leave ulcers
Contagious pustular dermatitis (orf)
- species
- morbidity, mortality
- lesion, development
- humans
o Similar to papular stomatitis but specific to small ruminants, more exudative
o High morbidity and may cause death in suckling lambs/kids
o Proliferative scabby lesions on lips, face, udder, feet; may extend into mouth
o Starts as papules that become pustules, rupture, and form scabs
o Potentially zoonotic
Coronaviruses
- environmental survival
- tropism, replication site
- lesions
- signs
- regeneration and recovery
- All are enveloped ssRNA viruses (poor survival outside host)
- Infect and replicate in apical cytoplasm of enterocytes on tips and sides of villi
o Exfoliation of infected cells causes villus atrophy and fusion
o Malabsorptive diarrhea due to defective lipid absorption (even before cells slough)
o Crypt hyperplasia allows regeneration in 2-3 days
o Recovery in 4-6 days if survive dehydration and electrolyte imbalances
Coronaviruses of swine
- signs in suckling pigs
- seasonality
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- 3 forms
> signs, morbidity, mortality
> neonates
> enzootic herd signs
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- signs, PM lesions
- All cause vomiting, diarrhea, and wasting in suckling pigs, mostly due to enteritis
- Problem in winter because enveloped virus can’t survive sun or heat
<><><><> - Transmissible gastroenteritis virus (TGEV)
o Clinical disease in any age, high morbidity in naïve herds but milder in adults
o Severe diarrhea and nearly 100% mortality in piglets <10-14 days old
o Recall neonates can’t regenerate enterocytes as effectively
o Enzootic herds: high mortality in gilt litters, low mortality but diarrhea and wasting in
weaned pigs with waning colostral immunity
<><> - Porcine epidemic diarrhea virus (PED): clinically identical to TGEV
<><> - Porcine deltacoronavirus: similar to TGEV but clinically milder
<><><><> - Undifferentiated diarrhea
- Lymphatics are empty due to malabsorption - Flaccid, thin-walled intestines with liquid contents
- Cold, dehydrated and wasted piglets with fecal soiling due to diarrhea
Coronaviruses in cattle
- Diarrhea in neonates
> common? other pathogens?
- tropism
- problems, recovery
- lesions?
o Common, occurs alone or with other agents (especially severe if with BVD)
o Infects enterocytes of SI and colon, causing severe diarrhea
o Often also damages Peyer’s patches, may cause respiratory disease
o Calves will still eat, recover in 5-6 days if they survive dehydration and electrolyte
imbalances
- gross lesion nonspecific
Coronaviruses in cattle
Diarrhea in neonates differentials
by age
<7 days: E. coli
5-15 days: Rotavirus, cryptosporidiosis, infectious bovine rhinotracheitis Salmonella, BVD less likely
Coronaviruses in cattle
* Winter dysentery
- morbidity, mortality, age
- usual suspect
- lesions and signs
o High morbidity, low mortality syndrome of adult cattle
o Usually young, postpartum dairy cows, can occur in summer too
o Signs mostly related to colon lesions: bloody diarrhea, milk drop, anorexia, nasolacrimal discharge +/- cough
- Gross: linear congestion/hemorrhage of colon with bloody contents
Feline enteric coronavirus
- transmission
- signs, age
- FIP connection
o Feco-oral infection, ubiquitous and often subclinical
o Sometimes causes mild to moderate diarrhea in kittens
o ~13% never clear infection and are lifelong carriers – these can progress to FIP
Feline infectious peritonitis (FIP)
- signalment
- enteric connection
- cells, when disease occurs
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- lesions, forms
> which more common, Ddx
> fatality
o Sporadic disease, often young males, purebreds
o De novo mutation from enteric form in every affected cat
o Replicates in macrophages – disease only occurs if cell-mediated response fails
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o Lesions exist on a continuum depending on dominant immune response mechanism
o Both forms have vasculitis and pyogranulomatous inflammation
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WET FIP
- Antibody-mediated Type III hypersensitivity
o More common, rapid, fatal clinical course
o Ocular and CNS lesions uncommon
o Main differential: bacterial peritonitis
- Marked abdominal distention
- Clear yellow fluid, fibrin/pyogranulomas on serosa
- Enlarged lymph nodes
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DRY FIP
- Cell-mediated
o More chronic progression
o May have ocular, CNS, renal, hepatic, or pancreatic lesions and/or colitis
o Differentials: lymphoma, steatitis (look for virus in lesions via PCR, IHC)
- Serosal pyogranulomas without effusion
- Can develop hydrocephalus if pyogranulomas obstruct CSF
Rotaviruses
- family, serogroups, most important
- usual clinical signs
- environmental survival
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- pathogenesis, cells infected
- adult vs young
- syncytia?
- diarrhea
- Infected enterocytes also produce….
- timing, recovery
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Always consider when??
- Family Reoviridae, 7 serogroups but group A is most common and important
o Infections are often subclinical - Resistant to environmental degradation (unlike coronaviruses)
<><><><> - Infect enterocytes on tips and sides of distal 50-66% of villi
o Fewer receptors used for virus entry in adults (disease usually in young animals)
o Infected cells can fuse (syncytia) and slough readily
o Malabsorptive diarrhea plus secretory enterotoxin
o Infected enterocytes also produce vasoactive compound that causes villus ischemia
o Virus is most prevalent at 18-24 hours post-infection and declines by 3-4 days
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Always consider rotavirus in diarrhea of young animals, especially with villus atrophy!
Rotaviruses in cattle
- age
- presentation
- gross lesion
- Mostly neonates (beef and dairy), often with other pathogens
- Most common between 4-5 days and 2-3 weeks old
- Milder than coronavirus and E. coli
- 1-3 days prepatent, 2-5 days of diarrhea
- Gross lesion: undifferentiated diarrhea
Rotaviruses in swine
- how common, presentation
- age, risk factors
- signs
- Common, often subclinical or with other pathogens
- Usually piglets with failure of passive transfer or post-weaning
- ‘White scours’ (steatorrhea) in 2-8 week old pigs
- Clinical signs, gross findings similar to TGEV but milder
Rotavirus in lambs, foals, and puppies
- age, mortality
- Also common in neonatal lambs, foals <3-4 months old (low mortality)
- May be fatal in puppies <1-2 weeks old
Parvoviruses
- genus, environmental survival
- replication, cells affected
- signs depend on
- damages what tissues
- Genus Parvovirus, small, nonenveloped, ssDNA viruses – hardy in environment
<><> - Virus replication can only happen during mitosis – affects mitotically active tissues (crypts) o The more mitotic activity, the worse the damage
o Signs depend on severity of crypt damage (can ulcerate if really severe)
o Also damages bone marrow, lymphoid tissue
Parvoviruses
Canine parvovirus 2 and mink enteritis virus are strains of …..
- what confers host range variability?
- Canine parvovirus 2 and mink enteritis virus are strains of feline panleukopenia
o Biologically distinct, different host cell ranges and virulence
o Variation in receptors used to enter cells confers host range variability
