Giardia lamblia: axenic growth in autoclaved and filtered Diamond's TYI-S-33 medium

The trophozoites of Giardia lamblia were gradually adapted to grow in both autoclaved and filtered Diamond's TYI-S-33 culture medium. Comparative growth studies indicated that the growth of organisms was significantly higher in filtered TYI-S-33 medium. In both types of media the exponential growth phase occurred between 48 and 96 h postinoculation. The mean number of trophozoites at 96 h was 1.94 × 10 5 and 4.82 × 10 5 cells/mL for autoclaved and filtered media, respectively. The generation times for the exponential growth phase were 9.66 h. for autoclaved and 7.69 h for filtered medium. The percentage of dead trophozoites was similar in both media and was 14% for the first 8 days postinoculation.