Lymphoid leukosis

Lymphoid leukosis is a type of avian leukosis, a group of diseases caused by the Avian leukosis virus. It primarily affects chickens, but can also occur in other bird species. The disease is characterized by the proliferation of lymphocytes, a type of white blood cell, leading to tumors in various organs.

Etiology

Lymphoid leukosis is caused by the subgroup A, B, and J of the avian leukosis virus, a retrovirus. The virus is transmitted vertically, from mother to offspring through the egg, and horizontally, from bird to bird through direct contact and exposure to contaminated feathers, feces, and dust.

Clinical signs

The clinical signs of lymphoid leukosis vary depending on the age of the bird and the organs affected. In young birds, the disease often results in anemia, emaciation, and diarrhea. In older birds, the disease can cause weight loss, decreased egg production, and enlargement of the abdomen due to tumor growth.

Diagnosis

The diagnosis of lymphoid leukosis is based on the clinical signs, necropsy findings, and laboratory tests. The presence of tumors in the liver, spleen, and kidneys, along with the proliferation of lymphocytes in the blood, are indicative of the disease. Laboratory tests, such as serology and polymerase chain reaction (PCR), can confirm the presence of the virus.

Treatment and control

There is no effective treatment for lymphoid leukosis. Control measures include the elimination of infected birds, biosecurity practices to prevent the spread of the virus, and the use of vaccines.

See also

• Avian leukosis
• Avian diseases
• Poultry farming