An Overview of Poultry Pathology Part I H

An Overview of Poultry Pathology Part I H. L. Shivaprasad California Animal Health and Food Safety Laboratory System, Tulare Branch University of California, Davis

California Animal Health & Food Safety Laboratory System School of Veterinary Medicine University of California, Davis Mission To provide the citizens of California with the highest quality diagnostic laboratory support for:

CAHFS Mission Disease Control Health Management Food Safety Public health Equine Health Dissemination of New Knowledge

CAHFS Laboratories Davis Turlock - Avian Tulare Layers Broilers San Bernardino Turkeys

Avian Taxonomy Phylum: Chordata Class: Aves Orders: 27 Families: 160 Genera: 1800 Species: 8600 Subspecies: >22, 000

Major Categories of Birds ØDomestic poultry (Egg laying and broiler chickens, turkeys and ducks) üCommercial and hobby/backyard flocks ØGame birds (Pheasant, Quail, Chukar) ØPet and exotic birds ØRatites (ostrich, emu, rhea) ØBirds of Prey ØBirds in captivity (Zoos) ØFree flying birds (California Fish & Game and National Wildlife Lab)

Segments of Poultry Industry (Broiler, turkey, egg layers) Ø Breeding – genetics – breeder replacements Ø Hatchery/custom hatching Ø Feed/feed mills Ø Housing – brooding/grow out (meat type) Ø Egg production Ø Processing (meat/eggs) Ø Transportation

Poultry Industry US/California üEggs (Pullets/layers) – White Leghorn üBroilers/Fryers & Roasters (meat-type ) ØWhite Plymouth Rock, White Cornish üTurkeys (Large White - Toms/Hens) üDucks (Pekin/Muscovy/Mullard) üPheasants (Ring necks: 18 - 20 weeks) üSquabs (500 g - 4 weeks) üQuail (meat/eggs), others?

Causes of Disease M: Malformation, Metabolic I : Infectious, Immunologic N: Neoplasia, Nutritional T: Toxic, Trauma Note: in commercial poultry infectious, nutritional and toxic causes are most important

Infectious ü Bacteria ü Viruses ü Fungi ü Parasites ü Rickettsia

Tests Essential for Disease Diagnosis ü History ü Clinical signs ü Necropsy (autopsy) ü Serology (ELISA, HA/HI, AGID, etc. ) ü Immunology (FA, IHC, etc. ) ü Bacteriology/Mycology ü Biotechnology

Tests Essential for Disease Diagnosis Histopathology ü Parasitology ü Toxicology ü Virology (egg embryos, cell culture) ü Electron microscopy (DEM, TEM) ü Hematology, chemistry, cytology ü Pathogenicity tests ü

Diagnostic Protocol q. Turn around time: üReport significant findings – same day üSerology, FA, IHC, bacteriology, biotechnology, Direct EM, histopathology – 12 to 48 to 72 hours üToxicology - 3 to 5 days üMycoplasma - 2 weeks üVirology - 3 to 6 weeks üIBV sequencing, TEM - variable

Disease Diagnoses - Philosophy ØQuality: Accuracy of results –Rapid turn around time –Thorough diagnostic work up –Communication with the clients • Use of friendly, common and understandable language

Disease Diagnoses – Philosophy Quality of service depends on the ‘quality and quantity of effort’ by the diagnostician/pathologist Øsometimes it is difficult to find a cause v. Client Confidentiality maintained

Avian Inflammation üreaction is rapid in birds, 36 hours üleakage of fibrin and fibrinogen common in early exudate üintense granulomatous reaction (12 hours) –coagulum of eosinophilic debris, degranulating heterophils, macrophages and giant cells

Avian Inflammation ümacrophages, heterophils and thrombocytes are active phagocytes üpus is caseous but liquefaction can occur übirds respond with granulomatous inflammation to many insults

Avian Inflammation Øacute inflammatory reaction in birds involves edema, congestion and vascular changes mediated by basophils and mast cells ü 1 -3 hrs: basophils, heterophils and monocytes ü 2 -6 hrs: basophils degranulate and die ü 6 -12 hours: lymphocytes, monocytes, macrophages

Avian Inflammation ü 12 -36 hours: lymphocytes, macrophages, giant cells –acute reaction peak by 12 hours (when giant cells appear) ü 36 -72 hours: regeneration and repair –fibroblasts, secondary lymphoid follicles, plasma cells –chronic reaction with caseation, macrophages, giant cells, granuloma formation

Avian Inflammation ØCells involved in inflammation: –Heterophils, mast cells, basophils, eosinophils –Thrombocytes –Monocytes/macrophages –Giant cells –Lymphocytes/plasma cells

Avian Inflammation Øcells involved in inflammation: –heterophils: have lance-shaped granules, lack myeloperoxidase and alkaline phosphatase, have β-glucoronidase and acid phosphatase üvery phagocytic ügranules tend to round up in tissues, difficult to identify

Avian Inflammation Øcells involved in inflammation (Cont. ) –eosinophils: have spherical granules üfunction is not known, delayed type IV hypersensitivity ? üassociated with eosinophilic enteritis in turkeys due to ascarids –basophils: contain histamine, involved in acute inflammation –thrombocytes: small round to oval cells with clear cytoplasm and small round nucleus (looks like small lymphocytes), phagocytic

Avian Inflammation Øcells involved in inflammation (cont. ) –monocytes: precursors to cells of MPS, phagocytic, can fuse to form multinucleated giant cells üCytokines; IL-1, IL-2, IL-6, IL-8, IL-15, IL-18, etc. , TNF, G-CSF, gamma interferon –lymphocytes: various morphologies involved in subacute inflammation including plasma cells

Fibrinosuppurative (heterophilic) inflammation – pericarditis, perihepatitis and airsacculitis

Fibrinosuppurative (heterophilic) cellulitis Fibrinosuppurative pneumonia Pus – liquefaction rare

Fibrinosuppurative (heterophilic) inflammation

Heterophils (Lance-shaped granules) Heterophils and a eosinophil (arrow)

Eosinophilic enteritis, Ascarid larvae - Turkey Eosinophils – Turkey intestine

Granulomatous (Pyo? ) inflammation

Granulomatous hepatitis (Yersinia pseudotuberculosis) Granulomatous inflammation

Granulomatous inflammation. Asper in giant cells. PAS

Fibrinous inflammation with bacteria. Gran. inflammation with Staphylococcus sp.

Avian Bacteria üE. coli üSalmonella sp. üChlamydophila psittaci üClostridia sp. üMycobacteria sp. üMycoplasma sp. üBordetella avium üPasteurella multocida üGallibacterium anatis üStaphylococcus sp. üStreptococcus sp.

Avian Bacteria (Cont) üEnterococcus sp. üOrnithobacterium rhinotracheale üErysipelothrix rhusiopathiae üPseudomonas aeruginosa üKlebsiella pneumoniae üRiemerella anatipestifer üAvibacterium (Haemophilus) paragallinarum üYersinia pseudotuberculosis üSpirochetes üListeria, Neisseria-like üothers

Colibacillosis Øany one of the syndromes in poultry caused by E. coli –colisepticemia, air sac disease(CRD), peritonitis, coligranuloma, salpingitis, omphalitis/yolk sac infection, cellulitis, osteomyelitis/synovitis, swollen head syndrome and panophthalmitis Øenteritis with AAEC, eae gene present –ceca most commonly involved –common in turkeys, others; chickens, pigeons, quail, partridges, pheasants, ducks, ostriches, psittacines, passerines, etc.

Omphalitis (Yolk stalk)

Omphalitis (yolk sac infection)

Hemorrhagic omphalitis

Fibrinous pericarditis, perihepatitis and airsacculitis Fibrinous pericarditis

Synovitis

Cellulitis Salpingitis

Typhlitis – Turkey poult

Attaching effacing E. coli (AEEC)– Turkey poult

Avian Salmonellosis ØA large group of acute or chronic diseases caused by one or more members of the genus Salmonella ØMajority of salmonella are ubiquitous ØSome are host specific –S. dublin in bovine, S. abortus equi in equine, S. choleraesuis in swine –S. Pullorum and S. Gallinarum in chicken

Avian Salmonellosis ØPullorum disease in poultry - S. Pullorum ØTyphoid disease in poultry - S. Gallinarum ØParatyphoid in poultry, ducks, pigeons, wild birds, psittacines, passerines, etc. – 10 -20 species; S. Typhimurium, S. Enteritidis, S. Heidelberg, S. Anatum, S. Derby, etc. ØArizonosis in turkey poults - S. arizonae –also in chicks, ducklings, psittacines, passerines, etc.

Pullorum Disease

Pullorum disease. 19 day-old chick. Typhlitis, splenitis, hepatitis, myocarditis

Pullorum Disease – 6 weekold Myocarditis/pericarditis, Chronic passive congestion, liver Pullorum Disease Gizzard – Granuloma’s

Pullorum Disease, adult chicken – Granulomatous oophoritis

Pullorum Disease Oophoritis, salpingitis, peritonitis Pullorum Disease Oophoritis

Salmonella Enteritidis- pericarditis, perihepatitis, peritonitis Oophoritis

Cholangiohepatitis - chicken S. Typhimurium Hepatitis – African Grey Parrot S. Typhimurium

S. arizonae – Poults. Clinical signs and Ophthalmitis

S. arizonae – Poults. Omphalitis and typhlitis

Pneumonia – Pigeon S. Typhimurium Peritonitis - Pigeon

Orchitis - Pigeon Typhlitis - Pheasant

Crow – Encephalitis S. Typhimurium Pigeon -Encephalitis (ventriculitis) S. Typhimurium

Clostridial diseases ØC. perfringens (type A most common) necrotic enteritis in poultry, ratites, psittacines, etc. ØC. colinum - ulcerative enteritis in poultry, esp. in quail (quail disease), toucans, ratites, etc. ØC. perfringens can also cause similar lesions ØC. difficile - entero/typhlocolitis in ratites (ostrich)

Clostridial diseases Øliver may have foci of necrosis and inflammation with these clostridial diseases ØC. septicum - gangrenous dermatitis in poultry, esp. turkeys and chickens (C. perfringens can also cause similar lesions) ØC. botulinum - limberneck in poultry

Necrotic Enteritis turkey, Clostridium perfringens

Ulcerative enteritis, quail – C. colinum

Necrotic Enteritis - ostrich, Clostridium perfringens Crop emphysema Lorikeet. C. perfringens

Hepatitis - ostrich, Clostridium difficile

Hepatitis - ostrich, Clostridium perfringence

Typhlitis - ostrich, Clostridium difficile

Mycobacteriosis Øchronic progressive disease of a variety of species of birds with unthriftiness, loss of weight, diarrhea, etc. –M. avium - wide host spectrum, poultry, pigeons, raptors, ratites, wild birds, psittacines , passerines, etc. –M. genavense - psittacines, passerines? –M. tuberculosis - psittacines, others? –M. bovis - psittacines, others?

Mycobacteriosis (M. avium) - chicken Hepatitis, splenitis Mycobacteriosis, psittacine Hepatitis – M. genavense

Coligranuloma’s (Hjarre’s disease)

Mycobacteriosis – cytology and histopathology

Mycoplasmosis Øimportant economic diseases of poultry caused by M. gallisepticum M. synoviae M. meleagridis M. iowae Ø 14 -20 or more Mycoplasma sp. are known –isolated from chickens, turkeys, pigeons, raptors, ratites, wild birds, psittacines, passerines, etc. –pathogenic significance?

Sinusitis – turkey Mycoplasma gallisepticum Airsacculitis and splenomegaly – chicken Mycoplasma synoviae

Turkey: Sinusitis and airsacculitis– Mycoplasma gallisepticum

Amyloid arthropathy – Brown Leghorn (BLH) chicken. Notice the orange exudate. Enterococcus faecalis/Mycoplas Amyloid arthropathy – BLH, Mycoplasma synoviae

Amyloidosis – synovium Chicken Amyloidosis – synovium Under polarizing light

Turkey coryza – Bordetellosis (B. avium) – Conjunctivitis and sinusitis Collapsed trachea

Turkey trachea- deciliation and attachment of B. avium

Chicken coryza - Avibacterium (Haemophilus) paragallinarum

Erysipelas infection – turkey, Splenitis Erysipelas infection – turkey, heart petechiae

Fowl cholera – Turkey P. multocida (pneumonia) Fowl (avian) cholera – duck, hepatitis

Fowl cholera –Turkey. Pneumonia due to P. multocida

Chronic fowl cholera – wattles enlarged (cellulitis) Chronic fowl cholera – Head tilt: otitis media

Pneumonia (turkey) - Ornithobacterium rhinotracheale

Turkey- Pulmonary edema due to O. rhinotracheale

Staphylococcosis (S. aureus) - turkey Green liver disease and Osteomyelitis

Staphylococcosis (S. aureus) – turkey. Granulomatous pneumonia

Avian Fungal Diseases ØAspergillosis ØCandidiasis (C. albicans, C. glabrata, etc. ) ØMacrorhabdus ornithogaster (Megabacteria) ØZygomycosis ØFavus (Microsporum gallinae) ØCryptococcosis ØMalassezia sp. ØRhodotorula sp. ØOthers: Penicillium sp, Pythium sp. Curvularia sp, Histoplasmosis, Scdedosporium sp, Ochroconis (Dactylariosis), etc.

Aspergillosis – lungs (brooder pneumonia), Turkey Aspergillosis – Syrinx

Aspergillosis – Thoracic cavity and pleura, chicken

Aspergillosis – Heart Red tail hawk Aspergillosis – brain Turkey

Aspergillus – mycelia Aspergillosis – Air sac, duck Aspergillus – Conidia

Candida – Crop, Turkey

Candida – Crop, Pigeon Candida – Oral cavity, Ostrich

Pseudomycelia and yeast forms of Candida Crop - Avian

Proventriculitis – Ostrich Zygomycosis

Favus – Microsporum gallinae

Chicken – Favus, Comb – H & E

Chicken – Favus Comb and Feather follicle - PAS

Avian Viruses üAvian Paramyxovirus (1 to 9. 1, 2, 3 and 5) üOrthomyxovirus (Avian Influenza) üPox - many (Fowl, turkey, pigeon, canary, etc. ) üHerpesvirus – many üRetrovirus (Lymphoid Leucosis, REV, Lympho Proliferative Disease of Turkeys) üCircovirus: CIAV, PBFD and others üCorona virus – IBV and enteric viruses

Avian Viruses (Cont) ØAdenovirus – Group I, III and others ØBirnavirus – Infectious Bursal Dis. Virus in chickens üAlso been identified in ostriches and rheas ØUnclassified Birnavirus in chickens? üAssociated with transmissible proventriculitis ØPicornavirus – Avian Encephalomyelitis in chickens (Hepatovirus - distantly related to Hepatitis A virus) üEnteroviruses – not well classified üDuck Virus Hepatitis type I üOthers: enteric disease in various species (turkeys, chickens, pheasants, quail, etc. )

Avian Viruses (Cont) üMetapneumovirus (Groups A, B, C and D) üTurkey rhinotracheitis and swollen head syndrome of Chickens üReo virus – viral arthritis and (CNS) in chickens, enteritis/bursal atrophy in turkeys üMuscovy duck, geese üRotavirus – enteritis primarily in turkey poults, chickens, others üAstrovirus – enteritis in poults, chickens, DVH type II and III, Avian nephritis virus in chicks

Avian Viruses (Cont) üParvovirus – Goose and Muscovy duck üAdeno associated parvovirus (dependovirus) ØPapovavirus: Papilloma and Polyomaviruses üPolyomavirus – Psittacines (Budgerigar Fledgling Disease Virus), Passerines (Finch, Canary), Goose (hemorrhagic nephritis enteritis), etc.

Avian Viruses (Cont) ØHepatitis E virus (Hepevirus) – Hepatitis splenomegaly syndrome/BLSD in chickens üDistantly related to human/swine virus ØArboviruses: üFlavi virus (WNV, Usutu), Togavirus (WEE, EEE, Highland J virus, Israeli Turkey Meningoencephalitis Virus)

Avian Viruses (Cont. ) ØBunyaviruses – many types üTurlock-like virus - Encephalitis and myocarditis in ostrich chick ØOthers: Hepadna B virus (ducks), Calicivirus, Wesselsbron, Crimean-Congo Hemorrhagic virus, Louping ill virus, etc. ØProventricular Dilatation Disease – Avian Bornavirus ØTurkey Viral Hepatitis – Novel Picornavirus ØMyocarditis in turkeys – Reovirus

Avian Herpesviruses ØMarek’s Disease (Gallid herpesvirus 2 and 3) –Primarily in chickens. Turkeys and quail susceptible ØInfectious Laryngotracheitis - ILT (Gallid 1) –Chickens, pheasants, peafowl ØTurkey Herpesvirus (Meleagrid HV 1) üUsed as vaccine for Marek’s disease ØDuck Herpesvirus (Duck Viral Enteritis), goose ØPsittacine Herpesviruses ØFinch Herpesvirus ØPigeon Herpesvirus ØOthers: Crane, Cormorant, Bobwhite Quail, Owl, Falcon, Eagle, Stork, Starling

Avian Paramyxoviruses Groups APMV-1 APMV-2 APMV-3 APMV-4 APMV-5 APMV-6 APMV-7 APMV-8 APMV-9 Primary Host Many Passer. /Turkey Psittacine Duck Budgerigar Duck, goose Pigeon/dove Goose Duck Other hosts Numerous Chicken/Psitt. Chicken? Passerines Goose, Rail None Turkey None

Avian Retroviruses ØLeukosis/sarcoma group. Disease in chickens –Genus: ALV- related viruses –Groups: A, B, C, D, E and J –Lymphoid leukosis and other tumors –Myelocytomatosis (J virus) and other tumors ØReticuloendotheliosis. In chickens, turkeys, etc. –Genus: REV group (related to murine leukemia virus) –Runting syndrome, chronic lymphoma, acute reticulum sarcoma –Chick syncytial virus, duck infectious anemia virus, spleen necrosis and others

Avian Adenoviruses ØGroup I – has 12 serotypes (Example CELO) –Inclusion Body Hepatitis in Chickens, others –Hydropericardium syndrome in Chickens –Quail Bronchitis ØGroup II –Hemorrhagic Enteritis Virus of Turkeys –Marble Spleen Disease of Pheasants –Splenomegaly in Chickens ØGroup III (Duck adenovirus) –Egg Drop Syndrome in Chickens

Avian Adenoviruses - others üPsittacines (group I, II and novel) üPigeons üRaptors: Falcons, Kestrels, Merlins üFinch, Partridges üGulls, Mures

Avian Circoviruses ØGenus: Gyrovirus –Chicken Infectious Anemia Virus (CIAV) ØGenus: Circovirus –Psittacines (Psittacine Beak and Feather Disease) –Pigeons and Doves (Pigeon circovirus) –Passerines (Finch and Canary) –Gulls and Ravens –Ducks, geese and swans

Marek’s Disease Ømost common well studied and complex diseases of young (and adult) chickens – quail and turkeys are also susceptible etiology: cell-associated alpha herpesvirus ØPathogenesis: virus replicates in feather follicle epithelium, infection through respiratory route, viremia, infection of B cells, cytolysis, infection of activated T cells, cytolysis, immunosuppression, infection of other organs like nerves (paralysis & blindness), latency, transformation of T cells (CD 4), lymphoma

Marek’s – Skin/feathers Marek’s – Skin/feather Intranuclear inclusions

Pathogenesis of Marek’s disease (Herpesvirus)

Marek’s – Thymic atrophy Marek’s – Bursal atrophy and exudate

Marek’s – Sciatic and brachial nerves affected

Marek’s – Liver and Spleen – diffuse lymphoma Marek’s – Liver lymphoma

Marek’s – kidneys and proventriculus

Marek’s – Lymphoma in heart and skeletal muscle

Marek’s – thymus and eye

Leukosis/Sarcoma Group ØGenus, ALV- related viruses of family Retrovirus –six subgroups; A, B, C and D (exogenous viruses), E (endogenous) & J (recombinant) • A, B and J are common in the field, C and D are rare –various oncogenes been identified (see table) –can produce a variety of neoplasms in chickens

Leukosis/Sarcoma Group –influenced by strain of virus, virus dose, route of inoculation, age of host, genotype and sex of host • neoplasms: sarcoma’s (fibro, osteochondro, myxo, histio, lympho, hemangio), meningioma, mesothelioma, eryhtroblastosis, myeloblastosis, nephroblastoma, granulosa cell tumor, hepatocellular carcinoma, glioma, (osteopetrosis), etc.

Lymphoid Leukosis ØDisease of semi-mature and mature chickens Øetiology: retrovirus of leukosis/sarcoma group –exogenous viruses, subgroups A, B, C and D ØTransmission: –horizontal, transient viremia, immunity, LL rare –egg transmission, chronic viremia, immune tolerance, LL common ØB cell lymphoma in various organs, bursa of Fabricius, liver, spleen, kidney, gonads, etc. ØOsteopetrosis: thickening of long bones –effect of virus on osteoblasts

Lymphoid leukosis (retrovirus) – Bursa of Fabricius, chicken

Osteopetrosis - chicken

Fibroma – chicken leg Embryonal nephroma - chicken

Myelocytomatosis ØNeoplastic disease primarily of broiler breeders and broilers Etiology: retrovirus, subgroup J (leukosis/sarcoma group) ØLesions: liver, spleen, kidney, sternum, etc. , with nodules made up immature granulocytes ØNeoplasms: myelocytoma, hemangiosarcoma, myxoma, carcinomas in liver, fibrosarcoma, lymphoma, ganglioneuroma, renal tumors, etc. Ø Multicentric histiocytosis/sarcoma – infected at hatch (not in immunotolerized chickens)

Myelocytomatosis (Retrovirus, j subgroup), thoracic cavity and liver - chicken

Hemangiosarcoma, lung chicken Ganglioneuroma, spleen - chicken

Reticuloendotheliosis (REV) ØIncludes runting syndrome, chronic lymphoma and acute reticulum cell sarcoma –primarily in chickens and turkeys Etiology: retrovirus of REV group, distinctly different from leucosis/sarcoma group ØLesions: –in runting synd; thymic and bursal atrophy, neuritis, lymphoma (similar to Marek’s disease) –in chronic lymphoma; bursal and visceral lymphoma (similar to Lymphoid Leucosis) –in acute reticulum cell sarcoma; enlarged liver, spleen, kidney, heart, gonads, etc.

REV (Retrovirus) Lymphoma, liver and spleen - turkey