undertopics p. 87 - Flashcards
Equine encephalosis
orbivirus, culicoides vector equines, elephants susceptible abortion in the first 5 months of pregnancy encephalosis, neuron damage no vaccine endemic in africa no vaccines not in europe midges =vectors
Avian orthoreovirus infections ages and signs
over 10 days of age only infection but no clinical signs
Reoviral diseases of Poultry
Tenosynovitis arthritis Enteritis, stunting disease (runting stunting syndrome, PEMS Helicopter disase Malabsorption sysndrome hydropericardium respiratory disease immunosupression
Reoviral diseases of poultry age
mainly in young broilers
Rotavirus infection in dometic animals aetiology
Reoviridae, Sedoreovirinae, Rotavirus genus
secondary e.coli infection will kill the animals
Rotavirus in domestic animals
worldwide occurence
with a secondary e.coli infection a high mortality is present
no germinative infection
mutliplication on enterocytes of few day old animals
frequent simultaneous infections with parvo, corona, astroviruses
maternal immunity is the only defence against rotaviruses
mainly in 1-2weeks of age,
sudden Massive diarrhea, not bloody
electrolytes for healing
very resistant in the environment
african horse sickness
mainly south africa Orbivirus genus, Reoviridae vector transmitted, high mortality - midges, gnats, mosquitos at least 9 serotypes with diverse virulence can infected carnivores with infected horse meat, blood or organs Zebras are the natural reservoir pulmonary form: dyspnea, sudden death respiratory form, resp signs subacute: cardiac dysfunction mixed form chronic form: recurrent fever vaccination in endemic countries
Orthoreovirus infections of domestic animals etiology
mammallian orthoreovirus world wide occurence mainly calves - mild enteritis, respiratory signs (pneumoenteritis) bacterial co infection leads to complication sheep - resp and enteric d horse - coughing, nasal discharge swine - diarrhea, encephalitis rabbit - diarrhea
Equine encephalosis
southern countries of africa, but in israel too
Orbivirus
Culicoides vector
equines, elephant is susceptible
frequently asymptomatic
neuron damage but no signs of inflammation
no vaccine
Infectious bursal disease etiology, occurence, age
Birnaviridae, Avibirnavirus, infectious bursal disease virus - IBDV
mainly chicken, but also turkey
mainly chicken between 3-6 weeks: permanent immunosuppression,
2-8 weeks: 5-100% mortality: fever, watery diarrhea, urate crystals on the feathers, anemia, later cyanosis,
over 8 weeks: no clinical signs,
world wide
chronic: bursa atrophy
vaccines available: attenuated, immunocomplex, inactivated, in ovo
destroys premature b lymphocytes in the gut
effect of the infection is influenced by age
higly contagious, watery diarrhea and cyanosis,
can remain infectivity for 1-4 months in the litter
shed in faeces
does not cause disease in adult chicken over 2 m of age
Hepatitis E aetiology, occurence, age
Ortohepevirus A & C ZOONOTIC - it infects pig, wild boar, deer, roe deer as well
worldwide
pigs infected at 12 weeks of age, rabbits infected at 9-10 weeks -> many are slaughtered with the active strain present (they are at peak shed when in slaughter house!!)
NO gross PM lesions, no treatment!
in humans it causes hepatitis that can be fatal, extrahepatic symptoms, in immunocompromised/pregnant it can cause abortion with the death of the mother.
vaccines are currently on trial.
avian hepatitis e: ortohepevirus B chicken big liver and spleen disease
chronic underproduction or egg drop
chicken big liver and spleen disease aetiology, age, symptoms
Ortohepevirus B
chronic underproduction or eggs drops up to 20%, anemia, premature moulting, mortality
chicken layers over 24 weeks, shed in faeces
enlarged liver, enlarged spleen
treatment not an option
prevention by hygiene
Equine encephalomyelitis caused by Togavirus aetilogy, occurence, pathology, clinical signs
Eastern, Western and Venezuelan Equine Encephalomyelitis
Togaviridae family, Alphavirus genus
Eastern: Canada, USA west coast, central america - bird: mosquito cycle
Western - canada, use west coast, mexico, south america - bird, mosquito rodent cycle
venezuelan - USa southern states, central and south america: enzootic in rodents, epizootic in Eq
abortive infection
unapperent infection
encephalitis, myelitis with a characteristic BIPHASIC fever, enteric symptoms
can cause abortion in human
vaccine in endemic countries
can cause asymptomatic infection
some strains of venezuelan horse encephalitis can be transmitted from horse to other host
vaccination to prevent in the americas
CS in birds, horses, humans
usually after heavy rainfall - in summer or rainy season
no gross pathology lesions
Equine infectious arteritis - etio, age, presence, clinical signs, vaccination, testing
Arteriviridae family - uniform without subtypes, enveloped virus
world wide in Eq, Su, Monkey
old or very young animals; fever
conunctivitis and subcutaneous edema adult horses: edema, urticaria, fever aborted fetuses with partial autolysis mare: abortion, stillbirth stallion: decreased fertility - long term carrier for years: persistence mostly it is asymptomatic though!!! vaccination is available test from semen, nasal fluid low mortality
is USUALLY asymptomatic the rate of seroconverted animals increases with age main target=macrophage persistence caused by stallions sexual and aerogen affects donkeys persistent carrying mortality is low vaccine is used reproduction problems/impotence in stallions Vaccination of colts before puberty can prevent the development of EAV-carrier is not resistant
PRRS etiology, genotypes, clinical signs, age, occurence, vaccination, replication
2 genotypes: Arteriviridae - European - 3 subtypes
US - 9 subtypes
saliva, nasal secretion sheddingg
first phase: young pigs: respiratory signs
sows: abortion and return to estrus
second phase: 1-4 months reproductive failure, high pre weaning mortality
boars - reduction in semen quality
suckling piglets up to 60% preweaning mortality
elimination only in closed herds
attenuated and inactivated vaccination but the different strains no cross protection, inactivated alone is not enough
BLUE EAR DISEASE
replication in macrophages and lymphocytes
Louping ill and tick born encephalitis
Flavi viridae Tick borne encephalitis - zoonotic: Central Europe, Ixodes ricinus, animals usually asymptomatic, humans more effected
Louping ill - UK, scandinavia, ixodes ricinus, sheep, domesticated and wild animals, humans, all ages, biphasic fever, vaccine available
- biphasic fever in both of them TBE is endemic in central europe transmitted via consumption of raw milk inactivated vaccines tick born encephalomyelitis mainly occurs clinically in humans europe, asia Tick-borne encephalomyelitis exists as natural foci infections. seasonal occurence
louping ill: Ixodes ricinus,
frequent in sheep , dd listeria, rabies, scrapie
weak resistance, euryxen
