avian influenza and newcastle disease

Question 1

what are the two notifiable poultry diseases

Answer 1

avian influenza
newcastle disease

pigeon paramyxovirus

Question 2

what type of viruses are newcastle and influenza

Answer 2

influenza=orthomyxovirus
newcastke disease=paramyxovirus

(both enveloped RNA with glycoprotein spikes H,N and H,N,F respectivley)

Question 3

what differs between these two virus that makes one harder to vaccinate against than the other

Answer 3

avian influenza has a segmented genome meaning that antigenic shift can occur. as a result there are many strains of varying virulence with no cross immunity between virus subtypes

Question 4

what type of AIV is of veterinary importance

Answer 4

type A

only virulent strains are notifiable

Question 5

which subtypes of AIV are of high pathogenicity

Answer 5

H5, H7 subtypes

Question 6

what are the clinical signs of general avian influenza

Answer 6

depression
dulness
ruffled feathers
cyanotic/necrotic comb/wattle
swollen head
reduce intake of feed and water
cyanosis of shanks
tracheal and gi haemorrhage

Question 7

once suspected what are the next steps takes

Answer 7

1. notify DEFRA
2. send samples to international reference lab
3. PCR of H5/H7 primers (pathogenicity testing)
4. subtyping by specialist labs

Question 8

is AIV stable outside the host

Answer 8

not really. killed by phenol, formailn and UV light

survive 2 weeks in dust and prefers cold wet conditions

Question 9

how is AIV spread

Answer 9

aerosol, feaces, water/food/surface contamination

Question 10

what is the control strategy for AIV

Answer 10

STAMPING OUT

Question 11

What are the 5 groups of Newcastle disease from least to most severe

Answer 11

asymptomatic enteric
lentogenic (mild resp)
mesogenic (resp, neuro)
neurotropic-valogenic (resp, neuro)
viscerotropic-valogenic (gut haemorrhage)

Question 12

what are general signs of NDV

Answer 12

ABNORMAL THIRST
loss of apetite
ruffled feathers

Question 13

what are clinical signs of neurological strains of NDV

Answer 13

tremors
twisted neck
convulsions
star-grazing

Question 14

what are the clinical signs of viscerotropic-valogenic strain of NDV

Answer 14

green-yellow diarrhoea

GI haemorrhage

Question 15

how do you diagnose NDV

Answer 15

serology by PCR

post mortem

Question 16

How would you vaccinate against NDV

Answer 16

broilers=LIVE VACCINE
1-2 times by spray, water or nasal routes

layers=LIVE OR INACTIVATED
give live 1-4 times 4-8 weeks apart by spray, water or nasal route
give 0.5ml inactivated by IM/SC route

breeders=same as broiler but can give inactivated twice

Question 17

what bacterial disease is of little significance in chicken but is of high public health importance

Answer 17

salmonella!

Question 18

what are the clinical signs of salmonellosis in humans

Answer 18

gastroenteritis
nausea
vomiting
diarrhoea
fever

Question 19

What are the 5 vaccination methods of chickens

Answer 19

1. Coarse spray
   for respiratory diseases. droplets cover birds and vaccine is either inhaled or pecked off feathers
2. drinking water
   blue dye used to ensure chickens have actually drank it
3. on food
4. injection
   (mareks only one given SC at day old)
5. IN OVO
   vaccine injected into egg through shell at 18 days of incubation.

Question 20

SUMMARY OF DISEASES AND SIGNS

Answer 20

Avian influenza=tracheal haemorrhage, cyanosis of comb/wattle, cyanosis of legs
Newcastle disease=abnormal dehydration and thirst, tremors, twisted neck, convulsions OR yellow diarrhoea, gut haemorrhage

Avian pneumovirus=respiratory, swollen head syndrome, loss in egg shell quality and pigmentation
poultry mycoplasmosis=lameness, swollen joints, brest blisters
infectious laryngeotracheitis=gasping, spit out mucus/blood, causeous plug in trachea.
infectious bronchitis=egg peritonitis

infectious bursal disease=muscular haemorrhage, proventricular/bursal haemorrhage
chicken anemia virus=yellow bone marrow
mareks disease=nerve swellings, tumors, splayed legs