References |
Disease Author |
Debra Bourne |
 |
Major References /
Reviews |
Code and Title List |
B12.55.w1, B15, B32.20.w8, B36.21.w21, B48.1.w1
J1.15.w4
J3.143.w1
J5.16.w1, J5.19.w6
J25.3.w1 |
Other References |
Code and Title List |
B11.37.w5, B11.37.w6, B13.32.w3, B13.46.w1, B14, B16.19.w1, B37.x.w1
J1.18.w2, J1.31.w2, J1.34.w2
J3.108.w2, J3.140.w2
J4.171.w2
J5.15.w1, J5.15.w2, J5.18.w2, J5.19.w1, J5.19.w4, J5.29.w2, J5.38.w3, J5.42.w1
J6.2.w1, J6.6.w1, J6.7.w1, J6.11.w2, J6.12.w1, J6.13.w2, J6.16.w1, J6.25.w2
J24.71.w1
In hedgehogs:
J137.87.w1
|
Detailed Clinical and Pathological Characteristics |
General |
This
disease varies from subclinical to severe disease with important losses
through illness, reduced egg production, and mortality. (B32.20.w8,
B36.21.w21) |
| WATERFOWL |
Clinical disease is rare in
waterfowl. Both nervous signs and general malaise with diarrhoea, polydipsia and
respiratory signs have been reported. |
| HEDGEHOGS |
Experimental infection has been demonstrated in the North African
hedgehog Aethechinus algirus (Atelerix
albiventris - Four-toed hedgehog). (J137.87.w1) |
| Clinical
Characteristics |
- Variable subclinical to fatal.
- Systemic or localised nervous, respiratory or gastrointestinal
signs (diarrhoea).
- May be general depression.
- May be fatal.
- (B48.1.w1)
(B48.1.w1)
Forms recognized in poultry:
- Viscerotropic velogenic Newcastle disease VVND (Doyle's form): An
acute lethal infection in all ages of chickens:
- Acute death;
- Listlessness;
- Weakness;
- Increased respiratory rate;
- Severe respiratory signs have occurred with this form in some
countries. (B32.20.w8)
- Head and periocular oedema;
- Mucoid nasal discharge;
- Prostration;
- Green diarrhoea
(not in birds dying early in the course of the
disease), sometimes bloodstained;
- Muscle tremors, torticollis,
opisthotonus and limb
paralysis may be seen prior to death.
- Neurotropic velogenic Newcastle disease or NVND (Beach's form):
Acute lethal disease in chickens of all ages.
- Sudden onset respiratory; neurological signs develop one or two days
later;
- Large decrease in egg production;
- Rarely diarrhoea
- Deaths.
- Mesogenic:
- Respiratory distress;
- Marked decreased egg production
- Occasionally nervous signs;
- Deaths in young birds.
- Lentigenic:
- In adults, mild respiratory disease may be seen or no clinical
signs.
- Serious respiratory signs may occur in young susceptible birds,
but this is not usually fatal.
- Mortality may occur due to complicating infections. (B32.20.w8)
- Asymptomatic lentigenic: No clinical signs in chicken
(infection of the intestines occurs).
- Note: Acute death without clinical signs may occur with highly
virulent strains.
- In turkeys, clinical signs are generally less severe than in
chickens. (B32.20.w8)
- In game birds (gallinaceous birds) the disease appears similar
to that seen in chickens. (B32.20.w8)
(B32.20.w8, B36.21.w21).
- Clinical course:
- In chickens, in general the disease is more acute in younger
birds, and may have a longer clinical course in older birds. (B32.20.w8)
In double-crested cormorants:
- In juveniles only.
- Torticollis (twisting of the head and neck)
- Ataxia (lack of muscular coordination)
- Tremors.
- Paresis or incomplete paralysis including unilateral or bilateral weakness of the legs
and wings.
- Clenched toes.
- Frequently fatal in nestlings.
- Unilateral or bilateral wing paralysis noted in survivors.
- (B36.21.w21).
|
| WATERFOWL |
- Mobility problems, local paresis and central nervous signs, gastro-intestinal signs,
conjunctivitis, respiratory signs. (B11.37.w5, B11.38.w6, B12.55.w1, B13.46.w1)
- CNS-related (central nervous system) signs have been seen on experimental infection in Anas
platyrhynchos - Mallard: lay on sternum, legs extended to sides slightly
but able to rise, later unable to rise, sometimes found on side ‘swimming’ with
legs, concurrent increased respiratory rate, sometimes unable to hold head up. Progressed
to torticollis, lateral deviation of head, wing droop, later paralysis of legs, muscle
tremors. (J5.16.w1,
B36.21.w21)
- In one experimentally infected Branta
canadensis - Canada goose lethargy, anorexia and
uncontrollable shaking of the head was followed by partial paralysis (J5.19.w6).
- Outbreaks in domestic ducks in Hong Kong produced diarrhoea, ocular discharge and
variable malaise, malaise, anorexia, polydipsia, wasting, coughing,
dyspnoea, nasal
discharge, head swelling, paraplegia and some sudden deaths; in laying ducks decreased egg
production and increased soft-shelled eggs were noted (J25.3.w1).
|
Incubation |
WATERFOWL |
- General for all species: two to15 days, average five to six days; variation depending on virus
strain, dose and route of exposure, host species, age and immune status, environmental
conditions and infection with other organisms (B32.20.w8).
- Initial signs two days after intravenous inoculation , mortality peak
three days post
inoculation in ducklings (J5.16.w1);
initial signs seven days post inoculation in a Canada goose (J5.19.w6).
- Initial signs two days after inoculation of a highly virulent form
into adult Anas
platyrhynchos - Mallard.(B36.21.w21)
|
| Mortality / Morbidity |
- Variable and highly host
dependent. (B32.20.w8)
- Pathogenicity in chickens
depends mainly on the infecting virus strain, although the age of the
host, the route of infection and environmental conditions may all affect
the disease. (B32.20.w8)
- Mortality may approach 100% in domestic chickens
of all ages with VVND (B32.20.w8,
B36.21.w21)
- Morbidity may approach 100% and mortality 50% in adults, 90% in young chickens with NVND
(B32.20.w8, B36.21.w21).
- Mesogenic strains cause low mortality except in young birds, although
the mortality of very young chicks is low.. (B36.21.w21).
- Lentigenic strains cause only mild or inapparent infection in adult chickens but may
cause respiratory signs in very young chicks.
- (B48.1.w1, B36.21.w21).
|
| WATERFOWL |
- Usually low in waterfowl; reports of deaths in wild waterfowl associated with NDV
are rare. 35-96% mortality in the Hong Kong outbreaks (J25.3.w1).
|
Pathology |
GROSS
LESIONS:
- Variable, non-specific; lesions Depend on the virus strain, hosts, other factors affecting disease
severity, and when in the course of the disease the examination is made.(B32.20.w8,
B36.21.w21, B48.1.w1).
- Gross lesions may be absent; if present then the following may be
seen: (B32.20.w8)
- Head:
- Facial oedema
- Conjunctivitis with congestion and haemorrhage visible on
refection of the eyelid.
- Gastrointestinal tract:
- Haemorrhagic/necrotic lesions in the intestines (with VVND): particularly
in the proventriculus, caecae and small intestine.
- Lesions appear to result from necrosis of either the
intestinal wall or from lymphoid foci (e.g. the caecal tonsils).
- Lesions may be evident on both the serosal and the mucosal
surfaces.
- The caecal tonsils may be enlarged and necrotic
- Respiratory tract:
- Haemorrhagic lesions.
- Tracheal congestion.
- Airsacullitis (even with relatively mild strains): thickening of
the air sacs, catarrhal or caseous exudates.
- Reproductive tract:
- In hens in lay - flaccid and degenerative ovarian follicles;
haemorrhagic stigmata may be present
- Haemorrhage and discolouration of reproductive tract.
- Egg yolk may be found within the abdomen
- CNS:
- Spleen:
- Necrosis, visible on the capsular surface and on the cut surface
(B32.20.w8)
HISTOPATHOLOGY:
In chickens:
- Variable depending on the virus strain, host and route of
infection. (B32.20.w8)
- CNS:
- Lesions are seen mainly in the cerebellum, medulla, midbrain,
brain stem and spinal cord; they are rarely seen in the cerebrum.
- Nonpurulent encephalomyelitis; neuronal degeneration, glial cell
foci, perivascular lymphocytic infiltrates, endothelial cell
proliferation.
- Respiratory tract:
- Upper respiratory tract: Mucosal congestion, oedema,
dense cellular infiltrate (lymphocytes and macrophages). In the
trachea, lesions may extend along the whole length, with loss of
cilia within two days of infection.
- N.B. lesions resolve rapidly and may not be present by as
soon as six days post infection.
- Lungs: parabronchial hyperaemia and oedema.
- Air sacs: oedema and cellular infiltration, with
increased thickness of the air sacs.
- Gastrointestinal tract:
- Haemorrhagic/necrotic lesions associated with lymphoid
aggregations.
- Other changes related to the vascular system (see below)
- Reproductive tract:
- In females, follicular atresia, inflammatory cell infiltration
and formation of lymphoid aggregates. Similar changes may be seen
in the oviduct.
- Cardiovascular system:
- In blood vessels of many organs, hyperaemia, oedema and
haemorrhage;
- The media may show hydropic degeneration; capillaries and
arterioles;
- Capillaries and arterioles may show hyalinization;
- In small vessels there may be hyaline thrombosis;
- In endothelial cells of vessels, necrosis may be seen.
- The heart may have some small necrotic foci, sometimes with
haemorrhage
- Lymphoid system:
- Regressive changes, with disappearance of lymphoid tissue.
- In subacute infections, reticulohistiocytic cell hyperplasia may
occur, particularly in the liver.
- In the spleen, necrotic lesions are present throughout.
- In the spleen and thymus, in cortical areas and germinal centers,
there may be focal vacuolation and destruction of
lymphocytes.
- In the Bursa of Fabricius, marked degeneration of the medullary
region
- Hepatic: Small necrotic foci in the liver, small necrotic and
sometimes haemorrhagic foci in the gallbladder.
- Pancreas: lymphocyte infiltration may occur.
- Skin:
- With VVND there may be skin haemorrhage and ulceration;
- The wattles and comb may show congestion and petechiae.
- Ocular: Conjunctival lesions may be seen associated with
haemorrhage.
(B32.20.w8)
In double-crested cormorants:
- Liver: Mild enlargement. (B36.21.w21)
- Spleen: mild enlargement, mottling. (B36.21.w21)
- Note: changes are non-specific and may be have been related
to other concurrent diseases. (B36.21.w21)
|
| WATERFOWL |
- Gross lesions variable, depending on the type of virus, host etc. May be no gross
lesions and none are pathognomonic (B32.20.w8).
- Darkening of breast and leg muscles and petechiae on heard and abdominal fat recorded in
green-winged teal (J1.15.w4).
|
Disease / Agent has been reported in either the wild or in
captivity in: |
| Disease reported
in:Green-winged teal Anas crecca (J1.15.w4).
Domestic duck (J25.3.w1).
Mallard Anas platyrhynchos (experimental infection)(J5.16.w1)
Canada goose Branta canadensis (experimental infection) (J5.19.w4).
Double-crested cormorant (Phalacrocorax auritus
- Double-crested Cormorant) in the
USA and Canada (B36.21.w21).
Virus has been isolated from, and/or antibodies detected in:
- Bean goose Anser fabalis, greater white-fronted goose Anser albifrons
(J1.34.w2).
- Canada goose Branta canadensis (J5.18.w2, J5.19.w4).
- Northern shoveler Anas clypeata (J538.w3).
- Mallard Anas platyrhynchos (J5.19.w4, J4.171.w2).
- Canada goose Branta canadensis, mallard Anas platyrhynchos, northern
pintail Anas acuta (B48.1.w1)
Mallard Anas platyrhynchos American wigeon Anas americana, northern pintail Anas
acuta, wood duck Aix sponsa, green-winged teal Anas crecca, blue-winged
teal Anas discors, gadwall Anas strepera, cinnamon teal Anas cyanoptera,
lesser scaup Aythya affinis, American black duck Anas rubripes, Canada goose
Branta canadensis (J1.18.w2).
- Mottled duck Anas fulvigula, Australian gray duck (Pacific black duck) Anas
superciliosa, grey teal Anas gracilis (B15).
- Mallard Anas platyrhynchos, Gadwall Anas strepera, Common pochard Aythya
ferina (J1.31.w2).
- Mallard Anas platyrhynchos, American Black duck Anas rubripes, Wood duck Aix
sponsa, Blue-winged teal Anas discors, green-winged teal Anas crecca (J5.29.w2).
- Domestic muscovy duck (J24.71.w1).
- Goosander (Common merganser) Mergus merganser (J3.143.w1)
- Domestic ducks Anas platyrhynchos domesticus (J6.12.w1).
In Hedgehogs:
Further information on Host species has only
been incorporated for species groups for which a full Wildpro "Health and
Management" module has been completed (i.e. for which a comprehensive literature
review has been undertaken). Host species with further information available are listed
below: |
Host Species
List |
(List does not contain all other species groups affected by this
infectious agent)
|
Disease / Agent has been specifically reported in
Free-ranging populations of: |
| Disease reported
in:[Green-winged teal Anas crecca - shortly after capture (J1.15.w4) ].
Double-crested cormorant (Phalacrocorax auritus
- Double-crested Cormorant) in the USA and Canada (B36.21.w21).
Virus has been isolated from, and/or antibodies detected in:
- Bean goose Anser fabalis, greater white-fronted goose Anser albifrons
(J1.34.w2).
- Canada goose Branta canadensis (J5.18.w2, J5.19.w4).
- Northern shoveler Anas clypeata (J5.38.w3).
- Canada goose Branta canadensis, mallard Anas platyrhynchos, northern
pintail Anas acuta (B48.1.w1)
Mallard Anas platyrhynchos (J5.19.w4, J4.171.w2).
- Mallard Anas platyrhynchos, American wigeon Anas americana, northern
pintail Anas acuta, wood duck Aix sponsa, green-winged teal Anas crecca,
blue-winged teal Anas discors, gadwall Anas strepera, cinnamon teal Anas
cyanoptera, lesser scaup Aythya affinis, American black duck Anas rubripes,
Canada goose Branta canadensis (J1.18.w2).
- Mottled duck Anas fulvigula, Australian gray duck (Pacific black duck) Anas
superciliosa, grey teal Anas gracilis (B15).
- Mallard Anas platyrhynchos, Gadwall Anas strepera, Common pochard Aythya
ferina (J1.31.w2).
- Mallard Anas platyrhynchos, American Black duck Anas rubripes, Wood duck Aix
sponsa, Blue-winged teal Anas discors, green-winged teal Anas crecca (J5.29.w2).
Further information on Host species has only
been incorporated for species groups for which a full Wildpro "Health and
Management" module has been completed (i.e. for which a comprehensive literature
review has been undertaken). Host species with further information available are listed
below: |
Host Species
List |
(List does not contain all other species groups affected by this
infectious agent)
|
