Chicken Anemia Agents refers to a group of viral pathogens that primarily affect chickens, causing a severe and highly contagious disease known as chicken anemia. Chicken anemia is characterized by depletion of bone marrow cells, resulting in immune suppression and anemia. The primary agents responsible for this disease are viruses belonging to the genus Gyrovirus within the family Anelloviridae.
These viruses are extremely small, non-enveloped, circular DNA viruses that mainly target chicken erythrocytes and lymphoid cells, including the bone marrow. They primarily affect young chicks, particularly those between two and six weeks old, although infections can occur in poultry of all ages. The transmission of chicken anemia agents commonly occurs vertically, with the virus being passed from infected breeders to their offspring, but horizontal transmission through fecal-oral route is also possible.
Clinical signs of chicken anemia include progressive lethargy, weight loss, paleness, and anemia, leading to severe immunosuppression and increased susceptibility to secondary infections. Mortality rates can vary, but they can reach up to 100% in some cases, especially when bursal atrophy and concurrent infections occur.
Prevention and control of chicken anemia agents involve strict biosecurity measures to prevent virus introduction and spread. Vaccines are available for prevention, and strict hygiene practices, such as disinfection of the environment and proper waste management, are crucial in controlling the disease. Additionally, culling of affected and carrier birds may be necessary to reduce the virus load in the flock.
