FIG. 2.

Estimates of population degradation dynamics for exposure to subfreezing temperatures at water potential conditions of −0.5 bar (solid gray line) and −1.0 bar (solid black line) and freeze-thaw cycling conditions at water potential conditions of −0.5 bar (dotted gray line) and −1.0 bar (dotted black line). Graph depicts proportion of potentially infective oocysts remaining relative to the number added for each trial (n₃/n₁) versus duration of exposure (days or number of freeze-thaw cycles). Note that estimates of degradation for freeze-thaw cycling are extrapolated beyond experimental conditions, which considered a maximum of six freeze-thaw cycles.