April 2018

Signalment (# 1759387):  Tissue from a chicken


HISTOPATHOLOGIC DESCRIPTION:  Scalded and plucked skin:  Multifocally within the superficial dermis, deep dermis, and panniculus, adjacent to feather follicles, arrector pullorum muscles, vessels, adipocytes, and occasionally nerves, there are nodular, up to 400 um diameter aggregates of small and medium sized lymphocytes admixed with occasional lymphoblasts/large lymphocytes, macrophages, and heterophils, and surrounded by areas of fibrosis. The epidermis and feathers are missing and there is disruption of dermal collagen (scalding and plucking artifact).

MORPHOLOGIC DIAGNOSIS:  Feathered skin:  Dermatitis, perifolliculitis, and panniculitis, lymphoproliferative, nodular, moderate, chicken, avian.

ETIOLOGIC DIAGNOSIS:  Alphaherpesviral dermatitis

CAUSE:  Marek’s disease virus (serotype 1), gallid herpesvirus 2

CONDITION:  Marek’s disease (MD)

SYNONYMS:  Fowl or range paralysis, polyneuritis, neurolymphomatosis gallinarum







ADDITIONAL DIAGNOSTIC TESTS:  Immunofluorescence, viral isolation, PCR, immunohistochemistry, electron microscopy



Adapted from Fenner’s Veterinary Virology (2017)

Viruses that can induce tumors in Domestic or Laboratory animals




Type of Tumor

DNA viruses




Rabbit fibroma virus and squirrel fibroma virus

Fibromas and myxomas in rabbits and squirrels (hyperplasia rather than neoplasia)


Yaba monkey tumor virus

Histiocytoma in monkeys

Herpesviridae/ Alphaherpesvirinae/ Mardivirus

Marek’s disease virus

T-cell lymphoma in fowl

Herpesviridae/ Gammaherpesvirinae/ Lymphocryptovirus

Epstein-Barr virus





Baboon herpes virus

Burkitt’s lymphoma, nasopharyngeal carcinoma, and B-cell lymphomas in humans and monkeys


Lymphomas in baboons

Herpesviridae/ Gammaherpesvirinae/ Rhadinovirus

Cottontail rabbit herpesvirus

Lymphoma in rabbits

Alloherpesviridae/ ranid herpesvirus

Lucké frog herpesvirus

Renal adenocarcinoma in frogs and tadpoles

Papillomaviridae/ multiple genera

Cottontail rabbit papillomavirus

Papillomas, skin cancers in rabbits


Bovine papillomavirus 1,4

Papillomas, carcinoma of gastrointestinal tract


Bovine papillomavirus 1,2

Papillomas, carcinoma of urinary bladder


Bovine papillomavirus 7

Papillomas, carcinoma of eye


Equine papillomavirus

Squamous cell carcinoma


Raccoon polyomavirus

Central nervous system tumors in racoons


Murine polyomavirus

Tumors in newborn rodents

Reverse Transcribing viruses



Hepadnaviridae/ Orthohepadnavirus

Human, woodchuck hepatitis viruses

Hepatocellular carcinomas in humans and woodchucks

Hepadnaviridae/ Avihepadnavirus

Duck hepatitis virus

Hepatocellular carcinomas in ducks

Retroviridae/ Alpharetrovirus

Avian leukosis viruses

Leukosis (lymphoma, leukemia), osteopetrosis, nephroblastoma in fowl


Rous sarcoma virus

Sarcoma in fowl


Avian myeloblastosis virus

Myeloblastosis in fowl

Retrooviridae/ Betaretrovirus

Mouse mammary tumor virus

Mammary carcinoma in mice


Mason-Pfizer monkey virus

Sarcoma and immunodeficiency disease in monkeys


Ovine pulmonary adenocarcinoma virus (Jaagsiekte virus)

Pulmonary adenocarcinoma in sheep

Retroviridae/ Gammaretrovirus

Feline leukemia virus

Leukemia in cats


Feline sarcoma virus

Sarcoma in cats


Murine leukemia and sarcoma viruses

Leukemia, lymphoma, and sarcoma in mice


Avian reticuloendotheliosis virus

Reticuloendotheliosis in fowl


Bovine leukemia virus

Leukemia (B-cell lymphoma) in cattle

* Not true oncogenic viruses.   They differ from all other viruses listed in that poxviruses replicate in cytoplasm and do not affect the cellular genome.


  1. Burgess SC, Basaran BH, Davison TF. Resistance to Marek’s disease herpesvirus-induced lymphoma is multiphasic and dependent on host genotype. Vet Pathol. 2001;38(2):129-42.
  2. Gimeno IM, Witter RL, Hunt HD, Lee LF, Reddy SM, Neumann U. Marek’s disease virus infection in the brain, cellular infiltration, and major histocompatibility antigen expression. Vet Pathol. 2001;38(5):491-503.
  3. Haesendonck R, Garmyn A, Dorrestein GM, et al. Marek’s disease virus associated ocular lymphoma in Roulroul partridges (Rollulus rouloul).  Avian Pathol.  2015;44(5):347-351.
  4. Heidari M, Wang D, Fitzgerald SD, Sun S. Severe necrotic dermatitis in the combs of line 63 chickens infected with Marek’s disease virus.  Avian Pathol.  2016;45(5):582-592.
  5. MacLachlan NJ, Dubovi EJ, eds. Fenner’s Veterinary Virology. 5th ed. Cambridge, MA: Elsevier; 2017:76-78,191-193,196-198.
  6. Mete A, Gharpure R, Pitesky ME, et al. Marek’s disease in backyard chickens, a study of pathologic findings and viral loads in tumorous and nontumorous birds.  Avian Dis.  2016;60(4):826-836.
  7. Ojkic D, Brash ML, Jackwood MW, Shivaprasad HL. Viral diseases.  In: Boulianne M, ed.  Avian Disease Manual. 7th ed.  Jacksonville, FL: American Association of Avian Pathologists, Inc; 2013:30-38.
  8. Schat KA, Venugopal N. Marek’s Disease. In: Swayne DE, ed. Diseases of Poultry. 13th ed. Ames, IA: John Wiley & Sons; 2013:515-552.
  9. Schock A, Garcia-Rueda C, Byas R, et al. Severe outbreak of Marek’s disease in crested partridges (Rollulus rouloul).  Vet Rec.  2016;179(17):443-444.
  10. Schwahn DJ, Rassette MSW. Pathology in practice. Marek’s disease. J Am Vet Med Assoc. 2013;242(11):1495-7.



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