Publications: Peer-reviewed journal articles (by staff)

The potential for cryopreserving larvae of the sea urchin, Evechinus chloroticus

1 January, 2006
CITATION

Adams SL, Hessian PA, Mladenov PV 2006. The potential for cryopreserving larvae of the sea urchin, Evechinus chloroticus. Cryobiology 52: 139-145.

ABSTRACT

Larvae of the sea urchin, Evechinus chloroticus, at varying stages of development, were assessed for their potential to survive cryopreservation. Ethylene glycol (EG) and dimethyl sulphoxide (Me2SO), at concentrations of 1-2 M, were evaluated as cryoprotectants (CPAs) in freezing regimes initially based on methods established for freezing larvae of other sea urchin species. Subsequent work varied cooling rate, holding temperature, holding time, and plunge temperature. Ethylene glycol was less toxic to larvae than MeSO. However, no larvae survived freezing and thawing in EG. Larvae frozen in MeSO at the gastrula stage and 4-armed pluteus stage regained motility post-thawing. The most successful freezing regime cooled straws containing larvae in 1.5 M Me2SO from 0 to -35 degrees C at 2.5 degrees C min(-1), held at -35 degrees C for 5 min, then plunged straws into liquid nitrogen. Motility was high 2-4 h post-thawing using this regime but decreased markedly within 24 h. Some 4-armed pluteus larvae that survived beyond this time developed through to metamorphosis and settled. Different Me2SO concentrations and supplementary trehalose did not improve long-term survival. Large variation in post-thaw survival was observed among batches of larvae produced from different females. (C) 2005 Elsevier Inc. All rights reserved.