Deutsches Krebsforschungszentrum,
E 160, Im Neuenheimer Feld 280, D-69120 Heidelberg,
FR Germany
70629 predominantly transgenic mouse embryos
prepared during the past eight years from 9727
pregnant female donors were cryopreserved protecting
125 mutant mouse lines against loss. In the means 7.26 embryos (8-cellers) per
pregnant donor were received. A conservation method leading to a high
revitalisation rate was chosen. To reduce the number of animals, just available
mice were used and breedings exclusively for cryopreservation were largely omitted.
Among others, the data were
analysed for influences in the gain of embryos by the genetic background and
the different housing conditions. Furthermore the long time activity of males
was investigated.
Our data show that the cryopreservation is a safe technology exhibiting the
advantage that (mutated) mouse lines out of current use are not to be kept in a
breeding nucleus. In parallel, this procedure leads to rederivation
making the export of mice to other facilities easier. The cryopreservation
of these 125 lines keeps the potential to save about 20000 laboratory mice per
year to be bred if they would be kept in a breeding stock. This is a major
contribution to the requirements of the “3R”-hypothesis developed by Russel and Burch to reduce the number of
laboratory animals used.
Key words: Cryopreservation,
transgenic mouse embryo, rederivation, embryo banking