medical Definition of lymphoid leukosis
: a neoplastic disease of chickens that is caused by a retrovirus (species Avian leukosis virus of the genus Alpharetrovirus) and is characterized by the formation of nodular or diffuse lymphoid tumors composed mostly of B cells and occurring especially in the bursa of Fabricius, liver, and spleen and sometimes in the kidneys and gonads
- Chickens with lymphoid leukosis show nonspecific clinical signs including inappetence, weakness, diarrhea, dehydration, and emaciation.
- —The Merck Veterinary Manual, 9th edition, 2005
