Comparison of Cryopreservation of Mouse Sperm vs Embryos
| Sperm | Embryos | |
| Advantage | Cheaper to cryopreserve, requires only one day of work, requires only two males/line | Embryos are frozen post fertilization, recovery to live offspring easier |
| Disadvantage | Only freeze one gamete, revival through IVF (labor extensive and costly), must use wildtype females as egg donors | Requires at least 8 females |
| # animals needed | 2 males/line | One heterozygous or homozygous breeder male and 8-16 weanling females |
| # days to complete | One day | One to two days |
| Cost | $605/2 males | $1010-$1700 |
- Sperm cryopreservation is an inexpensive and efficient means of long-term storage of valuable lines.
- Sperm cryopreservation works well for single gene mutations on standard genetic backgrounds.
- The only disadvantage is that live offspring must be recovered through in vitro fertilization (IVF).
Mouse sperm cryopreservation has the following steps:
- Contact the Animal Models Core (animalmodels@biotech.wisc.edu) to discuss scheduling.
- Assess animal colony to assure two proven male breeders (per line) would be available.
- Mice are transferred to the Biotechnology center on day of freezing. GEAM will submit animal transfer form to coordinate transfer of males on the day of cryopreservation.
- GEAM will sacrifice males and access sperm motility and concentration and give report to labs post-cryo.
- Sperm will be frozen and stored in liquid nitrogen tanks within GEAM.
- Recovery of live animals occurs by thawing and performing an IVF then surgically transferring the fertilized embryos into pseudopregnant recipients.
| MOUSE SPERM CRYOPRESERVATION (RECOMMEND FREEZING TWO MALES/LINE) | UW PRICE |
| 1 male/day | $410 |
| 2 males/day | $605 |
| 4 males/day | $990 |
| 8 males/day | $1800 |
| RAT SPERM CRYOPRESERVATION (RECOMMEND FREEZING TWO MALES/LINE) | UW PRICE | |
| 1 male/day | $700 | |
| 2 males/day | $825 | |