IMPROVED IN-VITRO CULTIVATION OF BABESIA-CABALLI

Babesia caballi infected erythrocytes were collected from the blood of an experimentally infected horse and could be continuously cultivated in vitro with parasitemia ranging from 2-4% in RPMI 1640 medium suppl emented with 2 mM L-glutamine, 20 mM HEPES and 40% adult horse serum i n a low oxygen atmosphere (2% O-2, 5% CO2 and 93% N-2. All attempts to increase parasitemia failed using other culture media, serum concentr ations and culture vessels. However, parasite growth was enhanced by t ransfer of cultures from a low oxygen to 5% CO2 in air, with parasitem ia ranging from 8-10%.