Cryopreservation and
short-term storage of sturgeon sperm, a review
R. Billard, J. Cosson, S.B. Noveiri, M.
Pourkazemi-2004
Aquaculture, 236(1-4): 1-9
Abstract:
Sturgeon sperm was cryopreserved in liquid nitrogen
or stored at 1–4 °C on a short-term basis. The objective was to establish
reliable technologies for the conservation of certain endangered sturgeon
species and for artificial reproduction in sturgeon farms. Cryopreseved
sperm was diluted in buffered extenders (pH between 8 and 8.5) containing
intracellular (dimethyl-sulfoxide (DMSO), methanol, ethylene glycol) or
extracellular (saccharose, egg yolk) cryoprotectants. The concentration of
intracellular cryoprotectants ranged from 5% to 20%. Tested freezing rates
were in a range of 0.5–18.5 °C/min and the thawing rate between 15 and 40
°C/min for 5 to 6 s. Ten to eight percent of the sperm were motile after
thawing. Fertilization rates up to 73–94% were reported for thawed sperm
but in most cases, average values were 20%.
The motility of non-frozen sperm was activated after
few days of in vitro storage. Motility declined with time depending on
oxygen availability in the milt, temperature (optimum near 0 °C) and pH;
though some spermatozoa were still motile after several weeks of storage.
(Muséum National d'Histoire Naturelle, Laboratoire
d'Ichthyologie Generale et Appliquee, Département Milieux et Peuplements
Aquatiques, 43 Rue Cuvier, Paris Cedex 05F-75231, France, e-mail: billard@mnhn.fr)