Figure 2 represents the protective effects of polyhydric
alcohols including ethylene glycol, glycerol and inositol and the
interaction with freezing velocities. The figure indicates
clearly that good effects of ethylene glycol and glycerol were
shown only in slow and the pellet freezing. On the contrary,
sugar alcohols and inositol were beneficial when freezings were
only the rapid and the pellet method. This may be due to
different eutectic points among substances tested. Also the
figure shows bull spermatozoa withstands to some degree freezing
as rapid as dropping it into liquid nitrogen.

(1) H. NAGASE, 1968, Proceed. 6th Intern. Congr, Anim. Reprod.
SR AT

(2) H. NAGASE, 1966, Jap. Agric, Res. Quart. 1, No. PAEES] ()

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