Lecture 4 - Cardio virology 2 Flashcards
what are the avian oncogenic retroviruses of veterinary importance
avian leukosis and sarcoma virus
how many groups of avian leukosis viruses are there
7 groups (A through G)
what groups of avian leukosis infect chickens
A - E
lymphoid leukosis
- B cells affected
- metastasize to produce tumors in organs
T/F: avian leukemia virus has a 4-month incubation period
TRUE
erythroblastosis
- immature erythrocytes affected
- gross pathological lesions (cherry red and enlarged)
myeloblastosis/myelocytomatosis
- granulocyte precursor affected
- similar presentation to erythroblastosis
how is avian leukosis/sarcoma virus transmitted
- through the egg (vertical)
- horizontal
- genetic transmission
what animals are most susceptible to lymphoid leukosis
congenitally infected
young chicks
Marek’s disease pathogenesis
- transforms T cells
- sexually immature chickens
- presents as paralysis and immunosuppression
avian reticuloendotheliosis pathogenesis
- transforms B and T cells
define neurolymphomatosis. what disease does this manifest in?
an abnormal accumulation of lymphocytes in the nerves resulting in paralysis
Marek’s disease
summarize the transmission of Marek’s in 4 steps
- respiratory infection
- T cell infection and altered migration pattern
- T cell accumulation in nerves and skin
- virus shed in infected skin cells
what avian diseases have vaccination control
- Marek’s disease
- IBDV
- CAV
describe the pathogenesis of Infectious bursal disease virus (IBDV)
- 3-6 week-old chicks infected via oral entry
- replicates in gut macrophages (enteric infection = diarrhea)
- primary viremia (spread to bursal lymph nodes and compromises immune system)
- secondary viremia (spread to kidneys and create immune complexes)
why is the initial outbreak of IBDV most severe compared to subsequent outbreaks
no maternal antibodies in the population the first time around
T/F: chicks vaccinated in egg are hatched immune to IBDV
TRUE
T/F: CAV has a high mortality alone
FALSE - Dual infections more common
how is CAV immunosuppressive
targets cells in bone marrow and thymus, interferes with vaccinal immune responses
how is CAV transmitted?
- horizontal (stable in environments)
- in-ovo
what is the only DNA animal virus that is transmitted biologically by arthropods
Africa Swine Fever Virus
what are reportable swine diseases
- ASFV
- classical swine fever virus
what animals are susceptible to ASFV
feral and domestic pigs
wild boars
warthogs
etc
what are the clinical signs of ASFV
- hemorrhagic disease
- D+/V+
- cyanosis
- lymphadenomegaly and splenomegaly
what are the 4 ways ASFV transmitted
- oronasal (direct)
- shed in all secretions
- ingestion of contaminated garbage and fomites
- sylvatic cycle via tick
what are the 3 outcomes of ASFV
- acute phase (spread to lymph organs, targets macrophages, destroys vascular endothelial cells)
- chronic phase (shedding virus, lymphadenomegaly, immune complexes causing inflammation)
- death
what biosecurity measures are in place for ASFV
- restrict swine movement from PR and Virgin Islands
- requirements for importing dogs from ASFV-affected countries
T/F: since 2019, pig populations are diminishing due to ASFV outbreaks
TRUE
pathogenesis of classical swine fever virus
- infects macrophages and endothelial cells
- results in endothelial damage, button ulcers, thrombosis, etc
how is CSFV transmitted
- fomites
- contact of contaminated uncooked pork products
- vertically
- horizontally
how does a piglet become persistently viremic
if mom is infected at 50-70 days of gestation
what is a circovirus?
small, circular DNA, non-enveloped virus that is highly environmentally stable
what are common PCVD complexes
- porcine dermatitis and nephropathy
- reproductive disease
- porcine respiratory disease complex
how do porcine circovirus types 2, 3, and 4 differ
type 2 - associated with post-weaning wasting syndrome, immune suppression component
type 3 - all PCVD complexes and congenital tremors
type 4 - emerging
