Fowl Leukosis: IV. Symptoms and Pathology

Abstract

FOWL leukosis has probably caused more losses to the poultry industry in this country during the last ten years than any other single disease. The complexity of the disease has led to a great deal of confusion as well as a variable terminology which expresses, in most cases, a quite adequate nomenclature for single manifestations but is inadequate as a name for this disease as a whole. There is usually considerable overlapping in the various expressions of the disease so that in each case the nomenclature used pertains to the type of cells in predominance. It would appear all types come from undifferentiated stages. These cells are the predominating cells in the lesions and are termed hemocytoblasts, which are cells possessing potentialities toward any of the blood cell types.A particular case in question can be definitely classified into a type only when enough of these cells have differentiated sufficiently .