Marek's Disease
What are the three phases of virus-cell interactions in which Marek's disease virus replication occurs?
- Productive infection - Latent infection - Transforming infection
Several chicks at a poultry farm are experiencing depression and ataxia. The farmer states that he noted one bird's eye has decreased in diameter and pupil size. What is your diagnosis?
Marek's disease (herpes virus)
How is Marek's disease diagnosed?
PCR for MD viral nucleic acid on peripheral blood white cell buffy coat or lymphoid tumors
The transformation of Marek's disease in ________ results in the formation of neoplastic lymphocytes
T lymphocytes
How is Marek's disease spread?
The infectious virus contaminates the premises through infected molted feathers and dander. Birds become infected when they inhale dust containing the virus
On gross necropsy of a chick that recently passed away, you observe swelling, loss of striations and a grey-yellow color of the sciatic nerve. What can you recommend to the owner of the chicken to prevent this disease within his flock, in the future?
This chick was infected with Marek's disease. There is no treatment. The emphasis is on prevention. - Vaccinate on day 1 or injected into the embryo 3 days prior to hatch.
True or false: During the latent infection, the viral genome is not expressed and no virus or tumor-associated antigen is produced
True
Where does full productive infection occur?
Within feather follicle epithelium
On necropsy of a chick, you note lymphoid tumors in the gonads, heart, liver, kidney and spleen. Which disease process are you concerned about?
Marek's disease
Which pathogen can be described as ubiquitous (nearly everywhere) in the chicken population?
Marek's disease
Chicks that become severely depressed and uncoordinated followed by unilateral paralysis of legs and wings, are likely infected with what disease process?
Marek's disease (herpes virus)
What is the causative agent of Marek's disease?
Herpes virus