Cryopreservation of sperm

The fundamental differences between our new cryopreservation protocol from those used by many is; a new dilution media, control of sperm concentration, a new Micro-Straw storage container and more stable and «strict» freezing and thawing curves.

To achieve this new protocol we have taken the knowledge and experience we gained from other species and our products and have run several tests and trials on zebrafish during the last 2 years. The final testing of our new protocol has shown that an average of over 80% fertilization after thawing is routinely achieved.

Twenty straws to preserve a line

With an average fertilization rate of over 80% we recommend that to cryopreserve a line, 20 straws are produced from 10 males will be sufficient. You can be safe in the knowledge that your significant line will be effectively backed-up and that with our post-thaw fertilization rates, you will be to reproduce the line efficiently.

Cryopreservation is performed at our special cryopreservation laboratory in Woburn, MA (and we will soon complete a further similar facility in Norway). You ship your zebrafish to us and we maintain the fish in client specific tank room until cryopreservation. After cryopreservation you can log in to the Core LIMS Database and monitor what lines and samples you have in stock at any time.

The frozen samples will be stored in client specific nitrogen tanks. The samples can be split and stored at 2 different locations to reduce risk further or as per the clients’ wishes. Cryogenetics always maintains the highest level of biosecurity and treats each client as unique to preserve confidentiality at all times.


NEW: 3 different logistics possibilities

To better serve client needs we have expanded our service range with the following options:

  • Sending your mature zebrafish males to Cryogenetics in Woburn, MA. 
  • Cryogenetics specialists conducting cryo-services at your local lab worldwide.
  • Cryogenetics team members or individual lab technicians collecting zebrafish sperm for overnight transport to Woburn, MA

In this way more clients can get access to our cryopreservation service.


Several benefits from cryopreserving at Cryogenetics

Cost effective

Once we have made you completely confident that you will have the lines successfully returned, you will soon find that it is more cost efficient to cryopreserve your important lines than the long-term maintenance of living lines. Maintaining zebrafish lines can be quite costly in terms of feed, power/services consumption, water monitoring, and aquaria consumables, external maintenance, and not least of all, gives the opportunity to save space in your facility. By cryopreserving the lines not in use, you have more space for the lines used in ongoing projects. This may well make the difference between maximizing the throughput of your existing facility rather than considering building a new facility or extending the old.

Space saving

By cryopreserving lines not in use, you can reduce the numbers of fish in your facility by approximately 30-50%

This also leads to savings of the staff time and energy. The staff can focus on other responsibilities in the facility rather than feeding and maintain fish that are not in daily use.

Permanent back-up

By cryopreserving valuable lines, you have them permanently backed up and protected against accidental loss of any kind.

High quality and rapid turnover

Cryopreservation and fertilization is core competencies within Cryogenetics staff. We also have the broad experience in handling valuable genetic samples of any kind.

Our new patent pending straw is sealed for biosecure storage and has a printed label to avoid any confusion about its content.  We plan to have a rapid turnover and generate 20 samples per line within 3 weeks of live animal shipment.