**6. Diagnosis of Marek's disease**

When Marek's disease is suspected and the consequences of the outbreak have been confirmed, the differential diagnosis is very important. It is based on finding clinical symptoms and pathological changes during the conduction of anatomopathological examination and comparing them with similar symptoms and macroscopic/ microskopic lesions which can be suspected/visualized in other diseases (**Table 1**).

1.Lymphoproliferative syndrome in turkeys. In fallen birds, a slight enlargement of the liver is visible with the presence of small, gray-white necrotic lesions resembling tuberculosis lesions. In turn, the spleen is significantly enlarged and resembles a marbled structure [47].


#### **Table 1.**

*The most important diseases or disease syndromes included in the diagnostic differentiations of Marek's disease.*

*Marek's Disease Is a Threat for Large Scale Poultry Production DOI: http://dx.doi.org/10.5772/intechopen.98939*

