Абстрактный
Review on marekâs disease and its economic importance
Feyera Gemeda Dima*, Abaynesh Girma
Marek's disease is a lymphoproliferative and neuropathic disease of domestic chickens, and less commonly, turkeys, quails and pheasants. It is caused by a highly contagious, cell- associated and oncogenic Alphaherpesvirus known as Marek's Disease Virus (MDV) or Gallidherpes virus 2 (GaHV-2). Marek’s disease is named after JozsefMarek, a Hungarian veterinarian and has different names such as: Range paralysis, Skin leukosis, Neuralleukosis, Neural lymphomatosis and pearl eye. It is recently classified as OIE list disease and characterized by number of conditions such as: lymphomas of visceral organs (ovaries, liver, spleen and kidneys), unilateral or bilateral enlargement of nerves particularly sciatic nerve and brachial nerve due to infiltration of lymphoblasts. Graying of iris due to lymphoblastoid cell infiltration (ocular form) and cutaneous form characterized by nodular lesions at the base of feather follicles. Although the inhalation of infected dust from poultry houses remains the most common route of disease spread and other less common like darkling beetles (Alphitobiusdiaperinus), could also play minor roles in indirect transmission.It is not zoonotic and environmental factors, maternal antibody, genetics and age at exposure, virus strain, virus dose and route are the determinant of MD susceptibility. The disease is distributed throughout the world andan outbreak of marek’s disease occurred in central Ethiopia and caused high mortality (46%) in commercial poultry farm .Since the disease causes a great economic loss, strict biosecurity, selectively breed chicken lines resistance against MD and vaccination are necessary for prevention and control of the disease. The aim of this paper is to review and present the available information on Marek’s disease and its economic importance.