Avian Leukosis Sarcoma Virus (ALSV) is a retrovirus classified under the family Retroviridae, subfamily Orthoretrovirinae, and genus Alpharetrovirus. ALSV primarily infects and causes tumors in various avian species, including chickens, turkeys, and quails. It is considered an oncovirus as it is capable of inducing neoplastic growth, particularly in lymphoid tissues and other organs.
The Avian Leukosis Sarcoma Virus is transmitted horizontally through direct contact with infected cells, blood, or body fluids. Vertical transmission can also occur via the egg, resulting in infected offspring. Young birds are more susceptible to infection, and the virus can remain dormant for an extended period before causing clinical signs or tumor formation.
The virus integrates its RNA genome into the host cell's DNA, leading to the production of viral proteins that can transform normal cells into cancerous cells. Different strains of ALSV exist, often characterized by their oncogenic potential and the specific types of tumors they induce, such as lymphomas, leukemias, erythroid leukosis, and myelocytomas.
Clinical signs of Avian Leukosis Sarcoma Virus infection may include weight loss, anemia, poor growth, decreased egg production, paralysis, or sudden death. Diagnostic tests involve serological assays to detect antibodies against ALSV or techniques targeting viral nucleic acids. Control measures focus on preventing spread and minimizing exposure through flock management practices, genetic selection, and vaccination programs.
Understanding the biology, transmission, and pathogenesis of Avian Leukosis Sarcoma Virus is crucial in developing effective strategies to control and manage this economically important viral infection in avian populations.
