Gross Morbid Pathology of Selected Avian Species

C. L. Davis Foundation “Gross Morbid Pathology of Animals”

March 19-23, 2007, A.F.I.P., Bethesda, MD

  1. Rob Porter, D.V.M., Ph.D., Diplomate American College of Veterinary Pathologists, Diplomate American College of Poultry VeterinariansWisconsin Veterinary Diagnostic Laboratory and University of Wisconsin School of Veterinary Medicine, Department of Pathobiological Sciences, 6101 Mineral Point Road, Madison, WI 53705

Tel: (608) 262-5432Fax: (608)

  1. Intro Slide: “Not all avian pathology is enlarged liver and spleens and fibrin-covered air sacs…only about 40% is!”
  1. Acknowledgements for contribution of photographs.

John Barnes, North CarolinaStateUniversity

John King, CornellUniversity

PurdueUniversity, ADDL

University of Wisconsin, Department of Pathobiological Sciences

  1. Poultry Industry

Broiler: Progeny of broiler breeders, indoor confinement/litter bedding, marketed at 5-7 weeks of age; feed efficiency <2.0.

Turkey: progeny of turkey breeders; poult = young turkey; indoor confinement or range rearing, hens marketed at 15 weeks and toms at 24-30 weeks (30-45 pounds)

Layer: Mostly cage layers; pullet = immature laying hen; lay for approximately 40 weeks, then molted at 60+ weeks of age, used for second cycle for another 30 weeks. Hen produces 250+ eggs in a lifetime (2 years).

Duck: White Pekin duck; raised on litter or plastic grating; feed efficiency <2.0, processed at 6 weeks of age (4.5 lbs).

  1. Oultine: systemic, Lymphohematopoietic, Musculoskeletal, Respiratory, Integumentary, Nervous, Cardiovascular, Digestive, Urogenital, Neoplasia.

Virus Taxonomy, Classification and Nomenclature of Viruses. C.M. Fauquet et al., eds. Elsevier Press, 2005.

Attendees receive interpretative summaries of significant avian pathology articles from Avian Diseases (2002-2006), Avian Pathology (2002-2006), Veterinary Pathology (2000-2006)

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SYSTEMIC DISEASES

Tissue/birdMorphologic/Etiologic DiagnosisEtiology/Disease

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  1. Head, chickenCyanosis/ edema wattle and combHighly pathogenic avian influenza (HPAI)
  2. Ventral neck, chickenEdemaHPAI
  3. Legs, chicken Mf cutaneous hemorrhageHPAI
  4. Proventriculus, chickenMf hemorrhagic proventriculitisHPAI
  5. Peritoneum, chickenMf peritoneal hemorrhageHPAI
  6. Trachea, chickenHemorrhagic tracheitisHPAI

Family Orthomyxoviridae, Genus Influenzavirus A, Species Influenza A virus:

negative stranded ssRNA virus

AI viruses have total of 15 HA and 9 NA. Pathogenicity determined by chick inoculation or by amino acid sequence at HA cleavage site. Most HPAI has been H5 or H7. Italy H5N2 and H7N1. Hong Kong H5N1 = “bird flu” with potential to directly infect humans. Virus replicates in endothelium, myofibers, renal tubules, pancreatic acinar cells. Lesions of coagulative necrosis and vascular thrombosis/ischemia.

DDX: END, ILT, IBV, END, bacterial sepsis

  1. Eggs, turkeyShell thinning, wrinkling and depigmentationLow path AI

DDX: NDV, avian pneumovirus

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  1. Yolk sac/heart, chickFibrinous pericarditis/yolk sacculitisEscherichia coli
  2. Heart, chickenFibrinous pericarditisE. coli
  3. Liver, chickFibrinous perihepatitisE. coli
  4. Peritoneum, chickenFibrinous peritonitis, “egg yolk”E coli
  5. Oviduct, henFibrinous salpingitis/peritonitisE. coli
  6. Liver, intestine, henMF granulomatous (coligranuloma)E. coli

Most common poultry serotypes are O1, O2, O35, O78, and many are untypeable.

DDX, pericarditis: E coli, Chlamydophila, MG, P. multocida

DDX, granulomas: Mycobacteriosis, LL, Leukosis/sarcoma complex

DDX, egg yolk peritonitis: P. multocida, HPAI, Salmonella

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  1. Head, chickenFacial edemaExotic Newcastle Disease
  2. Proventriculus, chickenAnnular mucosal hemorrhageEND
  3. Ovary, henMf hemorrhagic oophoritisEND
  4. Intestine, chickenNecrohemorrhagic enterotyphlitis/tonsillar necrosisEND
  5. Esophagus, roosterMf necrohemorrhagic esophagitis/pharyngitis END
  6. Trachea, chickenHemorrhagic tracheitisEND

Family Paramyxoviridae, Subfam Paramyxovirinae, Genus Avulavirus,

Species Newcastle disease virus, negative stranded ssRNA virus

Exotic (Velogenic) Newcastle disease (END); also lentogenic (mild) and mesogenic (moderate) pathogenicity. Usu. lentogens in U.S. END usually introduced by birds that are more resistant to disease.

DDX, tracheitis: HPAI, ILT, IBV

DDX, enteritis: HPAI, erysipelas, DVE, acute FC

DDX, esophagitis: Trichomoniasis, HPAI, DVE

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  1. Head, turkeyCutaneous infarction Erysipelas rhusiopathiae

Causes swine erysipelas and erysipeloid of humans. Lesions of sepsis with bacterial emboli, thrombosis, necrosis and hemorrhage (closely resembles colibacillosis of broiler chickens).

Hemorrhagic hepatitis/myocarditis, Necrohemorrhagic splenitis

DDX: P. multocida, Salmonella, E. coli, HPAI and END.
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  1. Oviduct, turkeyFibrinoheterophilic salpingitisPasteurella multocida
  2. Wattle, rooster BBFibrinoheterophilic cellulitisP. multocida
  3. Lung, turkeyNecr. fibrinohet. pleuropneumoniaP. multocida
  4. Spleen air sac, turkeyFibrinous airsacculitis and necr. splenitisP. multocida
  5. Heart, turkeyFibrinoheterophilic pericarditisP. multocida

“Fowl cholera,” Sepsis of both domestic and wild birds. Sixteen serotypes- 1, 3 and 4 are most common isolates. Lesions of bacterial embolism, thrombosis, necrosis and disseminated intravascular coagulation.

DDX: Ornithobacterium, E. coli, chlamydiosis, Staph.aureus

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  1. Spleen, air sac, ducklingFibrinous airsacculitis/necr. splenitis Riemerella anatipestifer
  2. Brain, ducklingPurulent meningoencephalitisR. anatipestifer
  3. Heart, liver, ducklingFibrinous pericarditis/perihepatitisR. anatipestifer
  4. Oviduct, ducklingFibrinoheterophilic salpingitisR. anatipestifer

“New duck disease.” Closely related to Ornithobacterium rhinotracheale. Lesions of septicemia closely resemble colibacillosis of broiler chickens.

DDX: E. coli, chlamydiosis, P. multocida

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  1. Liver, poultMf necrotizing hepatitis Salmonella pullorum
  2. Heart, broilersMf granulomatous myocarditisSalmonella pullorum
  3. Heart, spleen, chickMf necrohemorrhagic splenitisSalmonella pullorum
  4. Cecum, poultFibrinonecrotic typhlitisSalmonella pullorum

New designation of “Salmonella enterica subspecies enterica serovar Gallinarum-Pullorum” represents combination of S. pullorum and S. gallinarum. S.gallinarum causes ovarian degeneration and sepsis in adult birds in contrast to S. pullorum. Nonmotile Salmonella: possess few flagella.

DDX: E. coli, Mycoplasma synoviae, viral arthritis-reovirus, paratyphoid salmonellae

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  1. Eye, poultHypopyonSalmonella arizona
  2. Brain, poultPurulent meningoencephalitisSalmonella arizona
  3. Air sac, poultFibrinous airsacculitisSalmonella arizona
  4. Cecum, chickNecrohemorrhagic typhlitisParatyphoid Sal.
  5. Liver, pigeonMf necrotizing hepatitisParatyphoid Sal.

Salmonella arizona; biochemically distinct from paratyphoid Salmonella but cause similar clinical disease and lesions. Paratyphoid salmonellae refers to the motile serotypes (approximately 2400), and does not include S. pullorum and S. gallinarum.

DDX: paratyphoid Salmonella, E. coli, pullorum-typhoid

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  1. Head, henFibrinoheterophilic cellulitisStaphylococcus aureus
  2. Tibiotarsus, henFibrinoheterophilic osteomyelitisStaphylococcus aureus
  3. Leg, turkeyFibrinoheterophilic arthritisStaphylococcus aureus
  4. Foot, duckPlantar pododermatitisStaphylococcus aureus
  5. Liver, henMf to coalesc. necrotizing hepatitis Staphylococcus aureus

S. aureus requires skin penetration. Coagulase positive strains are the most pathogenic.

DDX: other systemic bacteria, esp. P. multocida and E. coli

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LYMPHOHEMATOPOIETIC

Tissue/birdMorphologic/Etiologic DiagnosisEtiology/Disease

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  1. Wing, chickNecrohemorrhagic dermatitis Necrotic dermatitis
  2. Bursa of Fabricius, broiler Cloacal bursal atrophyChicken infectious anemia
  3. Thymus. chickThymic atrophyChicken infectious anemia
  4. Femur, chickBone marrow aplasiaChicken infectious anemia

Family Circoviridae, Genus Circovirus, Species Chicken anemia virus, ssDNA virus

Chicken infectious anemia virus: circovirus replicates in hematopoietic cells and T lymphocytes  anemia and immunosuppression. Circovirus immunosupression promotes Staphylococcus aureus/Clostridium infection in skin. Had been referred to as “blue wing disease,” but is actually necrotic dermatitis. DDX: exudative diathesis

DDX: IBDV, trichothecene mycotoxins

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  1. Cloacal bursa, broiler Necrohemorrhagic cloacal bursitisInfectious bursal disease
  2. Leg, broilerIntramuscular hemorrhageInfectious bursal disease

Family Birnaviridae, Genus Avibirnavirus, Species Infectious bursal disease virus; dsRNA virus

Replicates in bursa of Fabricius lymphocytes of young chickens, followed by spread to other lymphoid sites  cytolysis and immunosuppression. Classic serotype 1, variant serotype 1 and serotype 2 viruses.

DDX: ionophore toxicosis, chicken infectious anemia, trichothecene mycotoxins, exudative diathesis (vitamin E deficiency)

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  1. Liver, bursa, WL henHepatic/bursal lymphomaLymphoid leukosis
  2. Liver, WL henMf hepatic lymphomaLymphoid leukosis
  3. Liver, WL henDiffuse hepatic lymphomaLymphoid leukosis

Family Retroviridae, Subfamily Orthoretrovirinae, Genus Alpharetrovirus, Species Avian leukosis virus; DNA/RNA Reverse Transcribing virus

Retrovirus of leukosis/sarcoma complex. Chicken genome contains endogenous viral loci (ev). Exogenous virus subgroup A transmitted vertically and horizontally. Exogenous virus induces neoplastic transformation of B lymphocytes. Subgroups A-D avian leukosis viruses can produce lymphoid leukosis. ALV Subgroup J produces myelocytomatosis.

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  1. Lung, spleen, pheasant Splenomegaly/pulmonary edemaMarble spleen disease

Family Adenoviridae, Genus Siadenovirus, Species Turkey adenovirus A (Marble spleen disease virus), ds DNA virus

Type II adenovirus (old terminology) related to hemorrhagic enteritis virus of turkeys; pheasants 3 – 12 months, IgM-positive B cells and macrophages are primary viral targets. Death from pulmonary edema/hemorrhage (uncertain pathogenesis) or secondary infection.

DDX: Salmonella, erysipelas

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  1. Body, pulletMarek’s disease paralysisMarek’s disease
  2. Pelvic nerves, broilerNeural lymphomaMarek’s disease
  3. Liver, spleenHepatic/splenic lymphomaMarek’s disease
  4. Pectoral muscle, broilerMuscular lymphomaMarek’s disease
  5. Kidney, pulletRenal lymphomaMarek’s disease
  6. Eye, broilerOcular/iridial lymphomaMarek’s disease
  7. Body, processed broilerCutaneous lymphomaMarek’s disease

Family Herpesviridae, Subfamily Alphaherpesvirnae, Genus Mardivirus, Species Gallid herpesvirus 2 (Marek’s Disease virus type 1)

MD serotype 1 (oncogenic) strain. Productive infection (viral replication) in feather follicle epithelium and transmitted in dander. Neoplastic transforming infection and latent infection in T lymphocytes. Lesions observed as early as 4 weeks.

DDX: Mycobacteriosis, coligranuloma, lymphoid leukosis in older birds

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  1. Subcutis, Macaw Mf subcutaneous hemorrhage Avian polyomavirus
  2. Heart, liver, Macaw Anemia, epicardial hemorrhage, hepatomegalyAvian polyomavirus

Family Polyomaviridae, Genus Polyomavirus, Species Budgerigar fledgling disease polyomavirus (Avian polyomavirus), dsDNA virus

Originally identified as budgerigar fledgling disease/French molt. Papovaviridae contains papillomavirus and polyomavirus families. I have diagnosed in Macaw, Electus parrot, Budgerigar, Lovebird and Conure. Intranuclear inclusion bodies in spleen, kidney mesangial cells and liver Kupffer cells.

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MUSCULOSKELETAL SYSTEM

Tissue/birdMorphologic/Etiologic DiagnosisEtiology/Disease

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  1. Foot, parakeetArticular gout
  2. Leg, chickenArticular gout

Mostly males, occurs with or without visceral/renal gout; high protein in diet promotes hyperuricemia, possible genetic predisposition; occurs with or without renal disease or renal gout. Not as common as visceral gout.

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  1. Body, turkeyNonambulatory poultIonophore toxicosis
  2. Leg, turkeyMuscular necrosis/degenerationIonophore toxicosis:

Polyether ionophores: Promote movement of mono and divalent cations across cell membrane. Toxicosis causes cellular loss of K+ and gain of Ca+2 into mitochrondria  cell death. Myocytolysis with proliferation of satellite and myocyte nuclei.

DDX: Infectious bursal disease, chicken infectious anemia, exudative diathesis, injection site myopathy

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  1. Hock joint, broilerSerofibrinous arthritisMycoplasma synoviae
  2. Leg, broilerTenosynovitisMycoplasma synoviae

“Infectious tenosynovitis.” Chicken, turkey and guinea fowl. Usu. colonizes subclinical upper respiratory tract, but can invade synovial membranes to cause tenosynovitis and sternal bursitis. Vertical and horizontal transmission. Lameness is primary sign with occasional airsacculitis.

DDX: Staph. aureus, viral arthritis, salmonellae

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  1. Pectoral muscle, turkeyDeep pectoral m. infarctionDeep pectoral myopathy

“Green muscle disease,” turkeys (esp. breeder hens during artificial insemination) and meat-type chickens with vigorous exercise  swelling of deep pectoral muscle within fascial sheath  ischemic necrosis of muscle. Usually found at processing.

DDX: ionophore toxicosis, injection site myopathy

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  1. Skull, crested polish chickenOpen fontanelle, skullCommon in crested polish
  2. Skull, crested polish chicken Open fontanelle, melanosis

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  1. Vert. column, turkeyFibrinoheteophilic osteomyelitisStaph., P. multocida and E. coli

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  1. Leg, RoosterOsteopetrosis/periosteal hyperostosisLeukosis/sarcoma virus
  2. Leg, roosterOsteopetrosisALV

Retrovirus: many of the avian leukosis viruses causing lymphoid leukosis can also induce osteopetrosis. Infected osteoblasts proliferate and produce periosteal and some endosteal bone. Lesions begin in tibiotarsus and tarsometatarsus, but can spread to other long bones, pelvis and ribs.

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  1. Pectoral muscle, layer breeder Granulomatous myositis/cellulitis Killed vaccine injection

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  1. Body, ChickenGastroc. Tendon rupture, bilateralViral arthritis
  2. Leg, chickenGastroc. Tendon rupture with hemorrhageViral arthritis
  3. Leg, chickenGastroc. Tendon rupture with hemorrhageViral arthritis

Family Reoviridae, Genus Orthoreovirus, Species Avian orthoreovirus, dsRNA virus

Avian reovirus is transmitted both vertically and horizontally. Cause tenosynovitis + rupture and hemorrhage of gastrocnemius tendon (tendon tensile strength pullet > broiler). Often associated with heterophilic infiltrates in the myocardium.

DDX tenosynovitis: Staph.aureus, Mycoplasma synoviae, trauma

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  1. Leg, WL henAcute femoral fractureOsteomalacia
  2. Keelbone, WL henOsteomalaciaOsteomalacia
  3. Thorax, WL henOsteomalaciaOsteomalacia
  4. Ribs, chickMedial deviation ribs, ricketsRickets
  5. Head, chickPliable beak, ricketsRickets
  6. Ribs, chickRib fractures, Rickets Rickets

Laying hen mobilizes 10% of skeletal calcium into egg shell each day. Deficiencies of calcium, phosphorus and vitamin D3 (cholecalciferol) can promote osteoclastic resorption of bone without sufficient osteoblast activity.

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  1. Body, broiler SpondylolisthesisSpondylolisthesis
  2. Vertebral column, broilerDorsal deviation T6, S/C compression

Spondylolisthesis=“kinky back” of 3-6 week broilers. Deviation of T6 vertebral body resulting in spinal cord compression. Conformation defect (genetic trait) complicated by rapid growth rate of broiler.

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  1. Tibia, broilerTibial dyschondroplasia
  2. Tibia, turkeyOsteochondrosis/ Tibial dyschondroplasia

Core of avascular cartilage in proximal tibiotarsus (metaphysic) or tarsometatarsus + bowing of bone and lameness. Failure of blood vessels to invade zone of cartilage hypertrophy in growth plate. Promoted by genetic line of broiler and marginal deficiency of calcium or a Ca/P imbalance. Experimentally induced by Fusarium roseum toxin.

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  1. Leg, turkeyCurvature of tibiotarsusMycoplasma meleagridis

Turkey syndrome 65 chondrodystrophy: inadequate linear bone growth at physis while appositional growth remains normal; associated with MM infection (impaired vascular invasion) and genetic predisposition (autosomal recessive inheritance).

DDX: tibial dyschondroplasia, rickets; Chickens, turkeys, ratites: lateral rotation of 90-180 degrees is multifactorial; rapid growth rate with early nutritional deficiency (Ca, P, Vit D3, protein) complicated by poor traction.

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RESPIRATORY SYSTEM

Tissue/birdMorphologic/Etiologic DiagnosisEtiology/Disease

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  1. Body, chickChick-respiratory distressTracheal obstruction
  2. Trachea, chickFocal granulomatous bronchitisAspergillus fumigatus/flavus
  3. Lung, poultMf granulomatous pneumonia/airsacculitis Aspergillosis
  4. Lung, chickenGranulomatous airsacculitisAspergillosis

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  1. Spleen, air sac, parrotNecrotizing splenitisChlamydophila psittaci

Genus Chlamydophila includes C. psittaci, C. abortus, C. felis, C. caviae, C. pneumoniae and C. pecorum. Obligate intracellular parasite. Systemic inflammation characterized by necrosis and fibrinous exudates, hepatosplenomegaly.

Turkeys, pigeons, ducks and psittacine birds. Eight serovars (A-H): A = psittacine, B/E = pigeons, B/D = turkey. Obligate intracellular parasite.

DDX: P. multocida, Erysipelothrix, Pacheco’s disease, Staphylococcus, Salmonella

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  1. Oral cavity, poultCatarrhal rhinitis/blepharitisCryptosporidium baileyi

Cryptosporidium baileyi: chicken, turkey, duck- respiratory epithelium, bursa of Fabricius, cloaca; C. meleagridis- turkey and quail small intestine. Host specific and do not infect mammals.

DDX: Bordetella avium

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  1. Lung, poultMf granulomatous pneumoniaDactylaria gallopava;
  2. Air sac, poultFocal granulomatous airsacculitis Dactylaria gallopava

Contaminant in hard wood shavings; translucent to grey lesions in tissue compared to Aspergillus. Dematiaceous fungus with hyphae observed in H&E. Neurologic disease is most common clinical sign in chicks and poults. Lesions in eye, brain, lung and air sac.

DDX: Aspergillosis

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  1. Body, pulletRespiratory distressInfectious laryngotracheitis
  2. Trachea, pulletFibrinohemorrhagic tracheitis ILT
  3. Trachea, WL henFibrinonecrotic tracheitis with occlusionILT
  4. Trachea, WL henFibrinonecrotic tracheitis with glottis occlusionILT

Family Herpesviridae, Subfamily Alphaherpesvirnae, Genus Iltovirus, Species Gallid herpesvirus 1, (infectious laryngotracheitis virus), dsDNA virus

Propagated on chorioallantoic membrane of embryonated eggs. Cytolytic for respiratory epithelium of nasal sinus, conjunctiva, air sacs and trachea. No evidence of viremia. Trigeminal ganglion is site of viral latency.

DDX: fowl pox, infectious bronchitis, END, HPAI

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  1. Air sac, chickSerous airsacculitisInfectious bronchitis
  2. Kidney, broilerUrolithiasis/hydroureterIB, nephrotropic strain

Family Coronaviridae, Genus Coronavirus, Species Infectious bronchitis virus (Group 3 species), Positive sense ssRNA virus

Coronavirus of chickens that causes respiratory signs, decreased egg production and wrinkled egg shells in layers. Nephrotropic strains can cause urolithiasis and visceral gout.

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  1. Head, WL hen Marked exudative sinusitis/conjunctivitis Haemophilus paragallinarum

“Infectious coryza,” Chickens are the natural hosts of H. paragallinarum. Usually begins as catarrhal infection with facial edema later complicated by other bacteria  fibrinous to caseous inflammation.

DDX: P.multocida, E. coli, Staph. aureus, vitamin A deficiency, pox.

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  1. Head, turkeySerous/catarrhal infraorbital sinusitis Avian pneumovirus

Family Paramyxoviridae, Genus Metapneumovirus, Species Avian Metapneumovirus, negative sense ssRNA virus

Can also cause malformation of oviduct with misshapen eggs/poor shell quality. Associated with “swollen head syndrome” in chickens- fibrinpurulent exudates in subcutis of head, neck and wattles.

DDX: Mycoplasma gallisepticum, respiratory cryptosporidiosis (C. baileyi). ______

  1. Head, turkeyInfraorbital sinusitisMycoplasma gallisepticum
  2. Head, turkey Serous/catarrhal infraorbital sinusitis MG
  3. Air sac, poultMild acute serofibrinous airsacculitisMG
  4. Lung, liver, chickenFibrinous pericarditis and perihepatitisMG/E. coli

“Chronic respiratory disease of chickens” and “infectious sinusitis of turkeys;” usually young birds. Can cause decreased egg production in adults. MG occurs naturally in galliformes, especially chicken and turkey, but also isolated from gamebirds. Transmitted both vertically and horizontally. Infected birds remain carriers. Mycoplasma is extracellular parasite that causes degeneration of epithelial cells.

DDX: Cryptosporidiosis, avian pneumovirus

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  1. Air sac, poultMild, acute serofibrinous airsacculitis Mycoplasma meleagridis

Specific pathogen of turkeys in which primary lesion is airsacculitis of 1-4-week-old poults. Referred to as veneral disease of Tom turkeys. DDX: Mycoplasma synoviae, gallisepticum or iowae, Newcastle disease.

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  1. Air sac; poultSerous airsacculitisNewcastle disease (lentogen).

DDX: acute MG, MM, ORT, pneumovirus

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  1. Lung, heart, turkey Necrofibrinohet. pericarditis/pleuropneumoniaOrnithobacterium

rhinotracheale

Affects turkeys, chickens and many other galliformes. Airsacculitis and unilateral pneumonia in chickens; pneumonia/hepatosplenomegaly in turkeys. Fibrinopurulent arthritis and osteomyelitis in older turkeys and chickens.

DDX: P. multocida and E. coli.

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  1. Lung, pheasantAcute, diffuse hemorrhagic pneumoniaAvian paramyxovirus-3

Family Paramyxoviridae, Genus Avulavirus, Species Avian Paramyxovirus 3,

negative sense ssRNA virus

Avian paramyxovirus-3; AMPV-1, 2, 3, 6 and 7 are known to cause disease in poultry. APMV-2 and 3 cause mild respiratory signs and decreased egg production in turkey breeders. APMV-3 is subclinical or causes neurologic signs in psittacine birds.

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  1. Trachea, bobwhite quailFibrinonecrotic tracheitisQuail bronchitis

Family Adenoviridae, Genus Aviadenovirus, Species Quail bronchitis virus, dsDNA virus

Type 1 adenovirus causes high mortality in young bobwhite quail. Also causes multifocal necrotizing hepatitis, splenitis and pancreatitis.

DDX: Aspergillosis, Salmonella, E. coli

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  1. Trachea, chickenTracheal nematodiasis Syngamus trachea
  2. Trachea, peahenMf granulomatous tracheitis with nematodesSyngamus trachea

Direct or indirect (earthworms) life cycle. Affects most galliformes. Form granulomas at site of attachment to tracheal mucosa.

DDX, tracheal nodules: granulomatous nodules can resemble Marek’s disease lymphoma, ALV-induced myelocytoma or aspergillosis.

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  1. Air sac, chickenAir sac acariasisCytodites nudus

Cytodites nudus = air sac mite of galliformes; lives in bronchi, lungs, air sac, and bone cavities

Stenostoma tracheacolum: tracheal mite of passerines-finches, canaries

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  1. Head, poultSerous blepharitis, submand. edemaBordetella avium (acute)
  2. Body, poultFibrinous blepharitisB. avium (subacute)
  3. Trachea, turkeyTracheitis w/chrondrolysis/ luminal collapseB. avium

“Turkey coryza,” 2 to 6-week-old poults (and occasionally broilers) causing blepharitis and submandibular edema. Often concomitant infections. Colonizes apices of repiratory epithelium and produces cytotoxin that causes chondrolysis of tracheal rings.