Chronic lymphocytic leukaemia and lymphoma in an Iranian fat-tailed sheep: a case report

A 5-year-old Iranian fat-tailed sheep was referred to the Veterinary Clinic of Shiraz University in September 2003 with a history of emaciation, fever, decreased appetite, lethargy and cough. Small cutaneous and subcutaneous nodules were palpable, especially under the ribs on both sides of the thorax. Discrete cutaneous plaques and large scabby lesions were also observed. Very large mammary gland lymph nodes were noticed on palpation. Haematological and serum biochemical values were estimated through standard haematological and biochemical techniques. In this case a normocytic–normochromic anaemia, leukocytosis and lymphocytosis were found. The concentrations of blood urea nitrogen (BUN), creatinine, cholesterol and the activities of aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) were higher than the values reported for sheep. Necropsy findings revealed that the lymph nodes were affected in most organs. Malignant lymphoma in the kidney, heart, spleen, mammary glands, liver and bone marrow was observed. The histopathological appearance of the affected tissues varied considerably, depending upon the degree of tumour infiltration. According to the history, clinical signs, laboratory findings, necropsy findings and histopathological examination the case was diagnosed as chronic lymphocytic leukaemia and lymphoma.