[Field studies in sheep infected with Eperythrozoon ovis]

The concentration of hemoglobin, hematocrit, number of erythrocytes and content of iron in the bloodserum of 35 sheep or lambs from five herds in which Eperythrozoon ovis was demonstrated in summer 1994 in bloodsmears by staining with acridinorange are compared with the findings in 70 animals of the same farms which did not suffer from eperythrozoonosis or which were already treated. Sick animals showed significantly lower levels than clinically healthy sheep except for iron. Eperythrozoonosis is characterised by anaemia, poor weight gains or weight reduction. The mortality in lambs reaches up to 28%. Oxytetracyclin was injected subcutaneously for therapy in a single dose of 20 mg/kg bodyweight. Two weeks after treatment the lambs had less clinical symptoms, the ewes needed up to four weeks. Also eggs of trichostronglylids, coccidia, and once of tapeworms were demonstrated and specifically treated. The transmission of the disease and the economic impact are discussed.