Porcine viruses (lecture 6) Flashcards
What are the four viral causes of swine enteritis
- rotavirus
- transmissible gastroenteric virus
- porcine epidemic diarrhea virus
- delta coronavirus
sudden outbreaks of scour involving large numbers of litters with acute diarrhea and high mortality suggest
transmissible gastroenteritis, porcine epidemic diarrhea, and delta corona virus associated diarrhea
what would you suspect is the cause of diarrhea that comes in waves in individual litters within the second half of lactation
rotavirus
PED and TGEV are _____ viruses
corona
describe the mortality of PED in regards to piglet age
suckling piglet- 100%
piglets older than 10 days- 10%
adults and fattening pigs- less than 5%
describe clinical manifestations of PED
diarrhea, vomiting, dehydration, metabolic acidosis
what is the incubation period of PED
3-4 days
how do you dx PED
fresh sample (feces, oral fluids, serum) then ID the agent via RT-PCR, ELISA, virus isolation (difficult)
or serological test- ELISA, immunofluorescence
how long will maternal immunity last in protection against PED
4-13 days
Swine delta coronavirus has ____ mortality rates in nursing pigs compared to PED
lower
when do outbreaks of SDCV occur
at 3-5weeks of age
how is TGEV related to PRCoV
TGEV is PRCov with the deletion of 225 aa in spike protein
what are some clinical signs of TGE
vomiting, profuse watery yellow diarrhea, rapid weight loss and dehydration
what day of gestation will infection of porcine parvovirus not result in fetal death
after day 70 fetus is immunologically competent
what material would you send to lab to test for PPV
fetal parts and mummified fetus
list the manifestation of parvoviral disease in cats
panleukopenia, enteritis, cerebella hypoplasia, abortion, fetal death, mummification, infertility
list the manifestation of parvoviral disease in dogs
lymphopenia, enteritis, neonatal myocarditis
list the manifestation of parvoviral disease in pigs
still birth, abortion, fetal death, mummification, infertility
list the manifestation of parvoviral disease in cows
enteritis, fetal death, infertility
the porcine respiratory disease complex consists of
stress factors + viruses + bacteria
what are the viruses that contribute to the PRDC
pseudorabies virus (PRV)
porcine respiratory and reproductive syndrome virus (PRRSV)
Swine influeza virus (SIV)
Porcine respiratory corona virus (PRCV)
Porcine circo virus (PCV-2
Aujeszy disease virus is also called
suid herpesvirus / pseudorabies
how is suid herpesvirus spread
nose to nose, sexual, inhalation of droplets/ aerosolized particles, contaminated objects can spread the virus
what are the 4 steps of pathogenesis of suid herpesvirus in the natural host
- primary replication in the resp tract
- entry into the pns neurons and establishment of latency in trigeminal ganglion
- replication in the lymph nodes and viremia
- secondary replication in the placenta
dog sitting and posterior paralysis is seen in young piglets due to which virus
suid herpes virus
what are the clinical signs of suid herpes virus in older piglets
fever, LOA, vomiting and neural signs (twitching, falling, convulsions, paralysis)
what are the clinical signs of suid in weaner pigs and grower/ finisher pigs
respiratory signs (coughing, sneezing, laboured breathing)
what are the clinical sings of suid in adult pigs
mild or not there, gilts and sows may have reproductive issues
what gross lesions would you expect to see in a piglet with suid
lung edema with hemorrhages, stomach hemorrhages, hyperemia and necrosis in the tonsils, leptomeningeal hyperemia
what is the pathogenesis of suid herpes virus in non natural hosts
- primary replication in the resp tract
- entry into the pns neurons and productive replication in the trigeminal ganglia
suid causes what in non natural hosts? how?
neuropathic itch “mad itch”. the viruses replication in the pns neurons leads to synaptic transmission of neuro inflammatory signals to the brain and central inhibition of itch pathways is non function meaning the itch sensation cannot be stopped
what is the incubation period for PRV/SHV? when can the virus be isolated? when will antibodies be detectable?
2-5 days
8-25days
6-10 days
what family does swine influenza belong to
orthomyxoviridae
name the hosts of influenza A,B,C,D
A; animals and humans
B; only humans but serological evidence in pigs
C; humans, maybe seals and pigs
D; primary host is cattle, but other animals as well, humans are seropositive
what are the clinical signs of swine influenza
coughing, nasal discharge, elevated temp, LOA
how do you dx SIV
nasal/ tonsil swabs RT-PCR, ELISA, Haemaggultination
what clinical signs do you see with Porcine circovirus type 2-si
lack of clinical signs with minimal histo lesions, but may see inclusion bodies in lymphoid tissue
what clinical signs do you see in PCV-2SD
weight loss and pale skin, moderate to severe lymphocyte depletion with granulomatous inflammation, high amounts of PCV-2 in lymphoid tissues
PCV2 reproductive disease causes what clinical signs
abortions or mummification, fibrous to necrotizing myocarditis of fetuses with moderate to high amounts of PCV-2 in the heart
Porcine dermatitis and nephropathy syndrome caused by PCVD causes
dark red papules and macules on skin mainly on the hind end and limbs, swollen pale kidneys, necrotizing vasculitis and necrotizing fibrinous glomerulonephritis
how do you arrive to a PCV2 dx
clinical hx or herd, post mortem findings, immunohistochemity for virus on lymphatic tissue, PCR, qPCR
porcine respiratory and reproductive syndrome virus causes
porcine epidemic abortaion and respiratory syndrome, mystery disease, blue ear disease, atypical PRRSV, swine infertility respiratory syndrome
PRRS pathogenesis
targets macrophages and has primary sites in the lungs and lymphoid tissues with many other organs like kidney spleen heart thymus repro tract….
where is PRRSV found in chronic phase
peripheral lymph nodes and tonsils
clinical signs of PRRSV
Reproductive issues, respiratory disease
how can we control PRRSV
herd immunity via vxs, prevent introduction of new strains via animal semen fomite vector and aerosol contact, to be prrsv free depopulation and repopulation wtih regular serological resting
