Virology- Viral diseases of poultry 2

kelseyfmeyer's version from 2015-04-16 19:12

Avian influenza

Question Answer
etiological agent? DNA or RNA? Enveloped or naked?orthomyxoviridae, RNA, enveloped
unique features of the virusSEGMENTED, and NA/HA PEPLOMERES
where in the cell does avian influenza replicate?RNA THAT REPLICATES IN THE NUC!! (flus are weird.)
as a flu virus, it undergoes genetic reassortment...which type does shift AND drift?TypeA
what are the major reservoir of avian influenza?waterfowl
which strains did she note to be zoonotic?H5N1, H9N2 (Five and Nine are in order, and 1 and 2 are in order. and it's ALMOST 69 but not quite)
aka of a particular strain of this?"fowl plague" (when you have bird flu you feel like you have the plague)
"fowl plague" strain clinical signs?sudden death with no prodromal signs (PLAGUE OF DEATH)
clinical signs of older birds which survive fowl plague (highly virulent strain)?cessation of egg laying, respiratory distress, sinusitis, diarrhea, edema of the face and neck, cyanosis of the comb and wattles (getting the FLU, esp the worst one, makes me blue)
what is very important in determining the virulence of the strain of avian influenza?HA (hemagglutinin) peplomere
why does HA play an important role in virulence? how does this vary strain to strain?Epithelial cells of the respiratory and *GI* are usually affected by the HA (technically they cleave it to activate it), but in virulent strains, the HA is cleaved in OTHER tissues also, leading to systemic dz and death
what are the clinical signs/lesions/problems of the animal infected with the virulent strain?is viremia, multifocal lymphoid and visceral necrosis, pancreatitis, myocarditis, myositis and encephalitis
what are the gross lesions caused by virulent strains?Gross lesions include petechial hemorrhages and serous exudates in respiratory, digestive and cardiac tissues
how do you dx?Virus Isolation is essential to determine virulence! You get a sample via chloacal swab, and then it's injected into the sac of embryonaetd eggs and IDed by hemagglutination. Typing is then done by HA and NA inhibition assays (injecting butt stuff into a baby egg to watch it's blood clot from the flu is also just weird.)
after you have dxed, what must you do?* how?DETERMINE VIRULENCE! virus isolation
what are some non-contact ways this virus is transmitted?*can survive in feces, and in WATER AT A LOW TEMP! (hence, waterfowl shitting)
is there vx?vx not used, lots of probs with it
what are control measures to deal with this avian flu?NOTIFIABLE UNDER OIE at the international level, there are quarantine and removal programs at the national level, and locally, chicken facilities are usually wild-bird proof

Avian infectious bronchitis

Question Answer
etiological agent? DNA or RNA? Enveloped or naked?coronaviridae, RNA, enveloped (YELLOW CROWN was around a chickens bronchi)
what are clinical signs dependent on?Depending on the age, route of infection, immune status, and viral strain
what are the clinical signs of chicks which are _________ old (she gave clinical signs for this age)1-4wk old, virulent strains will cause gasping, coughing, rales, nasal exudates and respiratory distress
what is mortality like? when is there higher mortality?there is mortality, (abt 30%), higher in birds which get secondary infections
what are the clinical signs in birds in egg production?production show respiratory signs plus involvement of the reproductive tract with cessation of egg laying and when resumed there are egg abnormalities (pale, deformities, no shell, etc), and pasting (Bronchi glue the BUTT and then the eggs are FU**ED<--it rhymes)
what is pasting?their butt is glued shut with exudate/goop
what color casts will you find in the trachea of a bird with avian infectious bronchitis?YELLOW
what are the GROSS LESIONS youd find in avian infectious bronchitis?there is mucosal thickening with serous or catarrhal exudate in nares, trachea, bronchi and air sacs. Yellow casts block bronchi in young chicks causing death. Pneumonia and conjunctivitis may be seen and in laying hens, ova can rupture resulting in free yolk found in the abdominal cavity (cant breathe if bronchi full of yellow burst yolks)
how do you dx AIB?IF of tracheal smears, virus isolation, RT-PCR, types determined by serology
how is AIB transmitted?aerosols and ingestion of feces-contaminated feed and Fomites (so of course poop and aerosols, bc corona, and fomites prolly bc persisting in poop)
is there a vx?YES! either AVIRULENT FIELD ISOLATES or ATTENUATED. however, breaks are common
why is control difficult?persistently infected chickens!! (mom has a persistant bronchitis right now)

Avian infectious laringotracheitis

Question Answer
etioloigcal agent? DNA or RNA? Enveloped or Naked?Herpesviridae, Gallid herpesvirus 1, DNA, enveloped
what are the ages affected like for this one?all ages but it is most common in birds 4-18 months old
clinical signs?There is coughing, sneezing, nasal and ocular discharge, dyspnea, loud gasping and depression follows. in severe cases, "pump handle respiration" Expectoration of bloody mucus or frank blood can be observed (a pump that pumps out blood...that's as scary as herpes)
pathogenesis/ gross lesions? where?Necrosis, hemorrhage, ulceration and diphteric membranes occur in the larynx and trachea! there is latent infections (HERPES)
dx?IF of smears and virus isolation, serology,
ddx?fowl pox (diphteric form) and other respiratory diseases (AIB, avian flu)
how/who is the transmission?virus introduced by carrier birds (HERPES), transmitted by droplet and inhalation and less commonly ingestion
how fast does AIL spread?It spreads more slowly than Newcastle, influenza and infectious bronchitis (herpes likes to take it slow, baby)
is there vx?yes--> Vaccination protects against disease but not against infection

fowlpox (FINAL LIST SAYS: just as differential in diptheric from)

Question Answer
which strain has high mortality?Dipthteric form (high mortality)
etiological agent?poxvirus, DNA, enveloped
xmitted by?mosquito
geographic occurance?Fowlpox is a serious disease of poultry and occurs worldwide
how resistant?extremely resistant to dessication and can persist in the environment for long periods of time in scabs
xmission?scabs, fighting and pecking, mosquitos, lice and ticks and probably aerosols

chicken anemia

Question Answer
etiological agent?circoviridae, DNA, naked (RBCs are CIRCLES)
what does this virus cause in chickens?anemia, acute immunosuppressive dz
what kinda transmission?horizontal (direct contact and fomites) and vertical while there is viremia
how old do they start to show clinical signs, and what are the CSs?when they are 3 weeks old show lethargy, anorexia, depression and are pale
why is there anemia?The anemia is due to bone marrow aplasia and atrophy of lymphoid organs. there might be SQ and IM hemorrhages
dx?History, clinical signs (low PCV, blood looks watery and clots slowly),
is there a vx?yes

check yo self

Question Answer
4+wk to adult chickens getting sicknewcastle
ducks and geese with inapparent infectionsnewcastle (ducks and geese just outside the castle, not in it)
what are the three types of newcastle, and explain them?velogenic, mesogenic and lentogenic= high, moderate and low virulence respectively
up to 100% mortality in unvaccinated flocks and 10-20% mortality in vaccinated onesnewcastle
segmented genomeInfectious bursal disease (IBD) (and avian flu)
birnaviridaeinfectious bursal disease (IBD)
all secretions and excretions are able to transmit dznewcastle
affects YOUNG LAYER chickensIBD (infectious bursal disease) (poor layers gotta try to squeeze an egg out past a swollen bursa?)
what is the disease where only the one serotype causes disease in poultry? and what is that serotype?Infectious bursal disease (IBD), only serotype 1 causes disease (you only get 1 bursa!)
maternal Abs are helpul for first 4wk of lifenewcastle
maternal Abs are ineffective against strong variantsinfectious bursal disease (IBD) (bc destroying so many immene organs, maternal Abs just cant keep up)
enlarged kidneys with lots of urates is a red flag for...infectious bursal dz (IBD)
HERPES but with no specific numbermareks dz
virus can be obtained from DANDER IN FEATHER FOLICLES, and this is the source of transmissionMarek's dz
Asymmetric paralysis with incoordination, wing dropping, lowering of the head, and if the vagus is involved, crop dilation and gasping alsomareks
greying iris with irregular pupil...what dz, and why?Mareks, and greying because lymphoblastoid cell infiltration
Can affect nerves, eyes, and skinmareks
macrophage associated viremiamareks
infection of lymphoid cells of the thymus, bursa, bone marrow, and spleenmareks
Enlargement of peripheral nerve trunksmareks
innoculate chicken kidney with buffy coat to do virus isolationmareks
vx does NOT prevent transmission! Also, peripheral neurologic disease continues to occur but at reduced incidencemareks
birds with genetic resistance to the dz?mareks AND avian leukosis
infectious bursal disease has tropism for what cells?B lymphocytes
Tropism for B lymphocytes? T lymphocytes?B=infectious bursal dz. T=Marek's
Marek's has trophism for what cells?T-lymphocytes
see urate crystals in what? why?infective bursal dz, because of kidney dysfunction
affects birds over 14wk ageavian leukosis
congenital or genetic transmissionleukosis
incubator infectionavian leukosis
genetically resistant chickens!avian leukosis and mereks
RNA virus which replicates in the nucavian influenza, (orthomyxoviridae)
waterfowl reservoir?avian influenza
SWINE, AVIAN, EQUINE INFLUENZA...which is/are zoonotic?avian and swine are, equine isnt
pancreatitis and encephalitis are two signs of a virulent strainavian flu (flu so bad it's even in your pancreas? dayum)
can survive in low temp wateravian flu
if it's corona, in almost any sp, where does it affect?GI and/or resp
pastingavian infectious bronchitis
messed up looking eggsavian infectious bronchitis (bronchi glue the butt then the eggs are f**ed)
YELLOW GUNK/CASTS? RED GUNK/CASTS?Yellow=corona=avian infectious bronchitis. RED=herpes=Avian infectious laringotracheitis
see free yolk in body because of ruptured ova?avian infectious bronchitis
avirulent field isolates or attenuated vxavian infectious bronchitis
herps dzs?mareks and Avian infectious laringotracheitis
most common in birds 4-18 months oldAvian infectious laringotracheitis (starts with 4, where its ddx, bronchitis, left off) (18yo with herpes, lulz)
pump handle breathingAvian infectious laringotracheitis
dz with a strain which can be ddx for resp viruses (which esp.?)fowlpox, diptheric strain (esp laryngotracheitis)
watery blood which clots slowlychicken anemia
SQ and IM hemorrhageschicken anemia
persistantly infected chickensAvian infectious bronchitis (mareks too, bc herpes, and leukosis too bc retro, laryngotracheitis bc herpes)
SEGMENTEDIBD, avian influenza
GENETIC SHIFTIBD, avian influenza (typeA)
verticle transmissionleukosis (transovaranian in lentogenic newcastle, i think this counts?)
contains a ONCOGENEmareks, avian leukosis rarely does
immunosuppressionmareks, infectious bursal dz
ZOONOTICavian influenza (technically newcastle but she didnt emphasize)
no vxavian flu
notifiableavian flu (zonotic!)