Chicken anemia virus

Chicken anemia virus

Chicken anemia virus (CAV) is a virus that infects chickens, causing chicken infectious anemia. It is a member of the Anelloviridae family and the Gyrovirus genus. The virus is known for its ability to cause immunosuppression in infected birds, leading to increased susceptibility to secondary infections and poor vaccine responses.

Virology

CAV is a small, non-enveloped virus with a single-stranded, circular DNA genome. The genome is approximately 2.3 kilobases in length and encodes three proteins: VP1, VP2, and VP3. VP1 is the major capsid protein, VP2 is a scaffolding protein, and VP3, also known as apoptin, induces apoptosis in infected cells.

Transmission

The virus is primarily transmitted vertically from infected hens to their offspring through the egg. Horizontal transmission can also occur through direct contact with infected birds or contaminated environments. The virus is highly resistant to environmental conditions and can persist in poultry houses for extended periods.

Pathogenesis

CAV targets the bone marrow and thymus, leading to a reduction in the number of red blood cells and white blood cells. This results in anemia and immunosuppression. Infected birds may exhibit clinical signs such as lethargy, pale combs, and increased mortality, particularly in young chicks.

Diagnosis

Diagnosis of CAV infection can be achieved through various methods, including polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and virus isolation. Histopathological examination of the thymus and bone marrow can also aid in diagnosis.

Prevention and Control

Control of CAV involves good management practices, including biosecurity measures to prevent the introduction and spread of the virus. Vaccination of breeder flocks is an effective strategy to provide maternal antibodies to chicks, protecting them during the critical early stages of life.

See also

• Chicken infectious anemia
• Anelloviridae
• Gyrovirus
• Immunosuppression
• Apoptosis