Improved cryopreservation protocol for zebrafish sperm


Cryogenetics’ staff are highly trained in cryopreservation and in vitro fertilization techniques.

New cryopreservation protocol

Cryogenetics has developed a new cryopreservation protocol for zebrafish sperm that in lab tests achieves a mean fertilization rate of 80 %. This high recovery rate ensures that zebrafish lines can be revived at any time, with no risk of the loss of high-value genetics.

As part of the new cryopreservation protocol, Cryogenetics has designed a new micro-volume straw (patent pending) that is specialized for freezing small amounts (up to 20 µl) of diluted sperm. Each straw is labelled and color coded, making identification of the samples easy.

Cryogenetics aims to industrialize the process of cryopreservation of zebrafish sperm. The goal is to produce 10-20 straws per line within 2 weeks of receiving live animals at our facilities. Freezing of sperm will be offered both from single and pooled males.

Samples will be retrieved from storage when needed and shipped to the client for thawing and in vitro fertilization. Client staff training for in vitro fertilization will be provided by Cryogenetics, to enable clients to perform the procedure in their own laboratory.

Combining sperm from multiple males

We recommend pooling sperm from multiple males when cryopreserving zebrafish lines. By combining (pooling) sperm from multiple males, the volume and number of sperm avaliable is increased and allows for sperm concentration to be measured accurately. This in turn enables us to optimize the concentration and quality of each straw. By combining sperm from multiple males, the possibility of poor fertilization due to male to male variation in sperm quality is avoided. By having more material available, thorough quality control can be performed on one test straw, and an estimated expected fertilization result immediately available to the client. Since the material is pooled, quality of the test straw will be representative of all other samples from that line.