Fatal theileriosis in eland (Taurotragus oryx) : pathology of natural and experimental cases
Grootenhuis, J.G.; Morrison, W.I.; Karstad, L.; Sayer, P.D.; Young, A.S.; Murray, M.; Haller, R.D.
Research in Veterinary Science 29(2): 219-29u
1980
ISSN/ISBN: 0034-5288 PMID: 7193340 Document Number: 160248
Clinical, parasitological and pathological studies were made on 5 eland infected with Theileria. Three were natural Theileria infections while the other 2 were experimental cases. All eland died. Generalized lymph node enlargement was a common feature. Wasting occurred in the more prolonged cases and in 2 of the field cases severe terminal diarrhea developed. The 3rd field case died in severe respiratory distress. In all cases, up to 50% piroplasm parasitemia was found and schizonts were seen in lymph node biopsy samples and in lymphoid smears prepared at necropsy. These parasites showed the morphological characteristics of Theileria taurotragi. The cells parasitized by schizonts had the morphological features of large lymphoid cells. These were in filtrated widely throughout the tissues and organs examined including the lymphoid organs, the gastrointestinal tract (in 2 cases this was the cause of death), adrenal glands, liver, lungs and to a lesser extent, the heart and kidneys. In 1 case the brain was invaded. The severely affected organs were diffusely infiltrated with parasitized cells, both intravascularly and extravascularly. Lymphocytolysis, necrosis, thrombosis and hemorrhage were frequently encountered in association with parasitized cells. All eland involved, except one were males, despite the fact that there were more females in the herds.