Cryopreservation of monogonont rotifers

Development of technique to maintain viable clones in a frozen state would preserve the genotype and reduce routine maintenance for those clones not being actively studied. To this end, the authors have frozen Brachionus plicatilis in dimethyl sulfoxide at concentrations ranging from 6% to 18%. Survival rates decreased as the end point temperature was reduced from -20 degree C to -45 degree C, but did not decrease when the temperature was further reduced to -196 degree C (liquid nitrogen). Only 2% of the individuals survived freezing in liquid nitrogen.