Cryopreservation of the ovary by vitrification as an alternative to slow-cooling protocols.

Objective: To study the thermal properties of a cryoprotectant solution, called VS4, and of VS4-impregnated whole sheep ovaries with pedicle.

Design: Physical and experimental animal study.

Setting: Academic research environment.

Freezing or supercooling: how does an aquatic subterranean crustacean survive exposures at subzero temperatures?

Crystallization temperature (T(c)), resistance to inoculative freezing (IF), ice contents, bound water, protein and glycogen body contents were measured in the aquatic subterranean crustacean Niphargus rhenorhodanensis and in the morphologically close surface-dwelling aquatic crustacean Gammarus fossarum, both acclimated at 12 degrees C, 3 degrees C and -2 degrees C. Cold acclimation induced an increase in the T(c) values in both species but no survival was observed after thawing. However, after inoculation at high sub-zero temperatures, cold-acclimated N.