Thymic lymphosarcoma in three heifers.

Three heifers with the thymic form of lymphosarcoma were examined. In each of the 3 cases, fever, bloat, and jugular venous distention had developed. Detectable antibody to bovine leukosis virus was not found on agar gel immunodiffusion testing in any of the cases. Thymic lymphosarcoma was confirmed by necropsy and histologic examination. Thymic lymphosarcoma must be considered in the differential diagnosis in heifers with fever, bloat, and jugular venous distention.