In a recent case, discrete eosinophilic intranuclear and intracytoplasmic inclusions in
conjunctiva, esophagus, lung, brain, adrenal ganglia of a pheasant and in the brain of
a chicken with NDV
Eosinophilic intranuclear inclusions in hepatocytes in doves associated with
lentogenic type of NDV
Other Avian Paramyxoviruses
– PMV - 2 (Yucaipa):
Respiratory disease in young turkeys and drop in egg production in layers, chickens
are susceptible
– PMV - 3, two strains, turkey and psittacine
Turkey: egg production drop in turkeys
Psittacine; neurological and digestive problems in psittacines and passerines
Encephalitis with intranuclear and intracytoplasmic inclusion bodies in neurons
and glial cells
Myocarditis, pancreatitis with intranuclear inclusions
– PMV -5 (Kunitachi):
Enteritis and mortality in budgerigars and lorikeets
f. Avian pneumovirus
– Cause of Turkey Rhino Tracheitis (TRT) of turkeys, Swollen Head Syndrome (SHS)
of chickens, highly contagious respiratory diseases
– Etiology: pneumovirus (Paramyxoviridae)
– Lesions: swollen sinuses, sinusitis, tracheitis, rhinitis, conjunctivitis
g. Avian Influenza
Acute viral disease of poultry; turkeys and chickens and psittacines, passerines, ratites, etc.
– It has been isolated from many species of birds
– Waterfowl may serve as reservoirs
Etiology: type A influenza virus of family Orthomyxoviridae
– Numerous subtypes based on surface antigens, hemagglutinin (13) and neuraminidase (9)
Viruses of H5 (H5N2) and H7 (H7N1) subtypes are considered pathogenic, H1N1
(swine flu) in turkeys
H4N8, H4N6, H3N8 in exotic birds
H5N1 in chickens and humans, Hong Kong, 1997
Clinical signs: vary greatly, respiratory, digestive, ocular, neurological, sudden death, etc.
– Drop in egg production in layers
Lesions: vary greatly in pathogenicity
– Mildly pathogenic: catarrhal tracheitis, sinusitis, airsacculitis, conjunctivitis, pneumonia,
peritonitis, oopharitis, salpingitis, etc.
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– Highly pathogenic: hemorrhagic lesions in skin of face, comb & shanks and GI tract,
interstitial pneumonia & nephritis, encephalitis, conjunctivitis, myocarditis, adrenalitis,
pancreatitis, myositis, lymphoid necrosis, vasculitis and thrombosis, etc.
h. Avian Encephalomyelitis
Viral disease of young (1-3 weeks) chickens, turkeys, pheasants and coturnix quail
– Neurological signs (epidemic tremor)
– Drop in egg production in layers
– Egg transmitted
Etiology: enterovirus (family Picornaviridae)
Lesions: neuronal swelling, chromatolysis, lymphocytic perivascular cuffing, gliosis in brain
and lymphocytic foci in muscular layer of proventriculus and gizzard, pancreatitis
– A few survivors can develop cataract
i. Avian Pox
Slow spreading viral disease of chickens, turkeys, quail, pigeons, canaries, raptors,
psittacines, ostrich, peacock, waterfowl, etc.
– 60 species of wild birds
Etiology: poxvirus of genus Avipoxvirus, many strains
– Fowl pox, turkey pox, pigeon pox, canary pox, quail, mynah, psittacine, junco, sparrow,
starling, etc.
Signs: cutaneous, respiratory, digestive, ocular
– Septicemic form in canaries, 70 - 90% mortality
Lesions
– Gross:
Dry pox or cutaneous form: proliferative skin lesions on face, eyelids, beak, feet,
legs, vent, etc.
Wet pox or diphtheritic form: yellow raised plaques in sinus, trachea, oral cavity
esophagus/crop, conjunctiva, etc.
– Micro:
Proliferation of epithelial cells, ballooning degeneration with eosinophilic
intracytoplasmic inclusion bodies (pathognomonic)
Desquamative pneumonia in canaries
Some avipoxviruses are oncogenic, wart-like growth
j. Infectious Bursal disease
Acute viral disease of young chickens (1-6 weeks) and secondary immunosuppression
Turkeys and ducks, subclinical infection
Etiology: birnavirus
Lesions: enlarged and edematous bursa of Fabricius some times with hemorrhages and
atrophy in later stages, hemorrhages in skeletal muscle, thymic atrophy with virulent IBD
– Lymphoid necrosis and depletion
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– Secondary infections with inclusion body hepatitis, gangrenous dermatitis, bursal
cryptosporidiosis, etc.
k. Chicken Infectious Anemia
Viral disease of young chickens characterized by aplastic anemia and immunosuppression
Chicks 1-3 weeks of age most susceptible
Vertically transmitted
Etiology: a circovirus, genus Gyrovirus, family Circoviridae
Hematology: anemia, hematocrit less than 27% (N 35%), leukopenia, thrombocytopenia
– Due to cytotoxic effect of virus on bone marrow precursor cells
Lesions: pale bone marrow, severe thymic atrophy, atrophy of bursa, hemorrhages in skeletal
muscles
Lymphoid necrosis and depletion, bone marrow hypoplasia
– Gangrenous dermatitis, colibacillosis, aspergillosis, viral infection, etc.
Eosinophilic (red) intranuclear inclusions in mononuclear inflammatory cells
(macrophages?) of thymus, spleen, bone marrow, bursa, lung, etc. in some cases
– True nature of these inclusions is not known
l. Duck Viral Enteritis
Acute viral disease of primarily adult ducks, geese and swans characterized by high mortality
Etiology: herpesvirus
Lesions: hemorrhages on heart, liver, gizzard, fibrinonecrotic lesions in esophagus, rectum,
cloaca, bursa, annular band of hemorrhage and necrosis in intestine, ceca, and thymic
atrophy
– Necrosis, inflammation and intranuclear inclusions in liver, intestine, thymus, gland of
Harder, conjunctiva, etc.
– Esophagitis and bursal necrosis with intranuclear and intracytoplasmic inclusions in
mucosal cells
m. Duck virus hepatitis
Peracute viral infection of ducklings (< 5 weeks) characterized by high mortality
Etiology:
– DVH - 1, enterovirus
– DVH - 2, astrovirus
– DVH - 3, enterovirus (unrelated to DVH1)
Lesions: petechiae or ecchymotic hemorrhages and necrosis in liver, minimal inflammation
n. Parvovirus Infection
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Goose parvovirus (Derzsy’ disease): highly contagious disease of young geese and
Muscovy ducks
– Serofibrinous pericarditis and perihepatitis
– Myocarditis with intranuclear inclusions
Muscovy duck parvovirus
– Serologically related to goose parvovirus
– Causes locomotor problems with high mortality in 1-3 weeks-old ducks, loss of weight ,
pale leg muscles, serofibrinous pericarditis and perihepatitis
Myositis, myocarditis, encephalomyelitis, neuritis, etc.
– Ascites, round hearts in ducks recovered from infection
o. Avian Adenoviruses
Three groups:
– Group I - quail bronchitis, inclusion body hepatitis and hydropericardium syndrome in
chickens, also disease in turkeys, pigeons, psittacines, raptors, etc.
– Group II - hemorrhagic enteritis virus of turkeys (HEV), marble spleen disease of
pheasants (MSD) and splenomegaly of chickens
– Group III - egg drop syndrome of chickens with no apparent lesions but caused
tracheitis and bronchitis in goslings
Quail bronchitis
– High mortality in young bobwhite quail associated with bronchopneumonia, tracheitis,
hepatitis, pancreatitis, bursal necrosis, intranuclear inclusions
Inclusion body hepatitis of chickens, also in turkeys, guinea fowl, pigeons, psittacines, etc.
– In chickens usually secondary to immunosuppression caused by IBDV, CIAV
– Liver enlarged and mottled red/pale, foci of necrosis, inflammation and intranuclear
inclusion bodies, also pancreatitis
– Similar lesions seen in turkey poults, guinea fowl, pigeons
– Hepatitis, enteritis, bronchitis, pancreatitis, nephritis, encephalitis, etc., associated with
intranuclear inclusions in psittacines
Hemorrhagic enteritis virus (HEV) of turkeys and Marble spleen disease (MSD) of
pheasants
– Caused by group II adenovirus
– Guinea fowl, psittacines, (partridge) susceptible
– Young turkeys (4-12 weeks) and pheasants (3-8 months)
– With HEV, intestinal hemorrhage and enlarged mottled white spleen and
immunosuppression
Intranuclear inclusions in mononuclear cells of spleen and intestine, renal epithelial
cells in HEV
– In pheasants mottled white enlarged spleen, MPS cell hyperplasia, intranuclear inclusions
– Splenomegaly in chickens
p. Poult Enteritis
Disease of young turkeys, multiple etiologies
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Viruses include coronavirus (blue comb disease), enterovirus, rotavirus, astrovirus, etc.
Diarrhea, loss of weight, small intestine and ceca distended with watery or frothy contents
Mortality 1 - 55%, caseous exudate in bursa with coronavirus infection
Increased cellularity of lamina propria, necrosis of cells in lamina propria and enterocytes,
villus atrophy, lymphoid necrosis in thymus and bursa (virus?)
Eneteritis associated with rotavirus and enterovirus have been described in young
pheasants, quail, chukars, etc.
q. Herpesviruses
Psittacine Herpesvirus
– Probably a diverse group of viruses which infect a variety of psittacines
– Three diseases are known
PACHECO’S DISEASE
Acute viral disease of a variety of psittacines (common in 1980’s in US)
Lesions:
♦ enlarged liver occasionally with petechiae, enlarged spleen, fluid filled
intestine, diphteritic membrane in oral cavity, esophagus, etc.
♦ liver necrosis with or without inflammation, enteritis, stomatitis, esophagitis,
pancreatitis, conjunctivitis, splenic and bursal necrosis, nephritis with
intranuclear inclusion bodies
♦ syncytia formation with inclusions in liver
AMAZON TRACHEITIS, disease characterized by tracheitis, bronchitis, rhinitis,
laryngitis with syncytia formation and intranuclear inclusions
Virus has some cross reactivity with ILT virus of chickens
BUDGERIGAR HERPESVIRUS, rare disease associated with decreased hatchability and
“feather duster” plumage
Miscellaneous Herpesviruses
– GOOSE HERPERVIURS
Lesions like in Duck viral enteritis with intranuclear inclusion bodies and high
mortality in goslings
– PIGEON HERPESVIRUS
Common in young squabs characterized by hepatitis, pancreatitis, esophagitis
associated with intranuclear inclusions
Conjunctivitis, enteritis, myocarditis, encephalitis, laryngitis, splenitis, etc. can also
be seen
Raptors and budgies susceptible
– FINCH HERPESVIRUS (cytomegalovirus)
Disease of primarily Gouldian finches characterized by high mortality, conjunctivitis,
tracheitis, bronchitis, associated with cytomegalic cells and intranuclear inclusions
– OTHERS HERPES VIRUSES OF OWLS, FALCONS, EAGLES, CRANES, etc.
Hepatitis associated with intranuclear inclusion bodies
r. Psittacine Beak and Feather Disease