Enzootic bovine leukosis

This is a lymphocytic tumor due to bovine leukemia virus that is characterized by lymphocytosis and lymphoma formation at various sites of the body. There is no treatment method. The incidence of this disease is high in Iwate Prefecture, and our university has energetically studied this disease. This disease is classified into the enzootic type (adult type), calf type, thymus type, and the skin type. The causes of these types of disease are unclear.

Bovine leukosis
The incidence of this disease is especially high in Iwate Prefecture. Fever, anemia, swelling of the surface lymph nodes, decreased milk are observed before death. There are various types such as the enzootic adult type, calf type, thymus type, and the skin type. Autopsy findings are not uniform but include swelling and bleeding in the spleen, liver, kidneys, and lymph nodes and formation of nodules of various sizes localized in the heart, gastrointestinal walls, and the orbit.

Splenomegaly of bovine leukosis
The leukocyte count was 421,500/mm3, and the spleen weighed 19 kg. The size of the spleen (100 x 36 x 11 cm) was 20-23 times as large as the normal size. (register No. 2007)

Masanobu Goryo
Address inquiries to the following.

Department of Veterinary Pathology, Faculty of Agriculture, Iwate University., Morioka, 020-8550, Japan