Stimulus-triggered enhancement of chilling tolerance in zebrafish embryos.
BACKGROUND
Cryopreservation of zebrafish embryos is still an unsolved problem despite market demand and massive efforts to preserve genetic variation among numerous existing lines. Chilled storage of embryos might be a step towards developing successful cryopreservation, but no methods to date have worked.


METHODS
In the present study, we applied a novel strategy to improve the chilling tolerance of zebrafish embryos by introducing a preconditioning hydrostatic pressure treatment to the embryos. In our experiments, 26-somites and Prim-5 stage zebrafish embryos were chilled at 0°C for 24 hours after preconditioning. Embryo survival rate, ability to reach maturation and fertilizing capacity were tested.


RESULTS
Our results indicate that applied preconditioning technology made it possible for the chilled embryos to develop normally until maturity, and to produce healthy offspring as normal, thus passing on their genetic material successfully. Treated embryos had a significantly higher survival and better developmental rate, moreover the treated group had a higher ratio of normal morphology during continued development. While all controls from chilled embryos died by 30 day-post-fertilization, the treated group reached maturity (~90-120 days) and were able to reproduce, resulting in offspring in expected quantity and quality.


CONCLUSIONS
Based on our results, we conclude that the preconditioning technology represents a significant improvement in zebrafish embryo chilling tolerance, thus enabling a long-time survival. Furthermore, as embryonic development is arrested during chilled storage this technology also provides a solution to synchronize or delay the development.
Applied Cell Technology Ltd., Budapest, Hungary.
Bernadett
B
Faragó
Szent István University, Department of Aquaculture, Gödöllő, Hungary.
Tímea
T
Kollár
Applied Cell Technology Ltd., Budapest, Hungary.
Katalin
K
Szabó
Applied Cell Technology Ltd., Budapest, Hungary.
Csilla
C
Budai
Applied Cell Technology Ltd., Budapest, Hungary.
Eszter
E
Losonczi
Szent István University, Department of Aquaculture, Gödöllő, Hungary.
Gergely
G
Bernáth
Szent István University, Department of Aquaculture, Gödöllő, Hungary.
Zsolt
Z
Csenki-Bakos
Szent István University, Department of Aquaculture, Gödöllő, Hungary.
Béla
B
Urbányi
University of Veterinary Science, Faculty of Animal Hygiene and Herdhealth and Veterinary Ethology, Budapest, Hungary.
Csaba
C
Pribenszky
Szent István University, Department of Aquaculture, Gödöllő, Hungary.
Ákos
Á
Horváth
Applied Cell Technology Ltd., Budapest, Hungary.
Judit
J
Cserepes
D000220:Adaptation, Biological; D000818:Animals; D002470:Cell Survival; D003080:Cold Temperature; D015925:Cryopreservation / Q000379:methods; D003451:Cryoprotective Agents; D004625:Embryo, Nonmammalian / Q000187:drug effects; D005298:Fertility; D006874:Hydrostatic Pressure; D015027:Zebrafish
D003451:Cryoprotective Agents