Cryopreservation and Resuscitation




  • CryoCore links will be inactivated effective December 1st. All requests should be submitted via iLab using this link
    To sign up for iLab, click here. Sign-in via MyAccess will be available on December 1st.
    Once your iLab request is accepted, please submit LARC animal transfer request and reference your iLab request number
  • Rescue by In Vitro Fertilization (IVF)
                - Request form



The purpose of Cryopreservation Core is to ensure:
  1. Preservation
  2. Sharing capacities
  3. Availability
  4. Protection
  • Sperm and epididymal tissues are cryo preserved in vials
  • Stored in liquid nitrogen
  • Quality controls include motility of sperm after thawing (PI will be notified if sperm quality is unacceptable)
  • In vitro fertilization (IVF) is preferred method to obtain large number of embryos
  • IVF can be performed for embryo cryo, rederivation, resuscitation from frozen sperm, and to rescue a problem strain.
  • Use 2 IVF’s per line avg.
Number of Mice Needed
  • 2 healthy male mice (reproductively active)
  • 2 healthy reproductively active males.
  • Females (2 IVF's) - WT purchased by core (approx. 12-15 per IVF) or provided by lab for homozygous lines or with multiple unlinked mutations and unique genetic background.
Amount Generated
  • 18-20 vials
  • Cryoarchive 200-250 embryos per line (8 straws when using WT oocyte donors). Number will vary with number of females provided. See note below
Age of Needed Mice
  • Males: 8-20 weeks
  • Males: 8-24 weeks
  • Females: 3-12 weeks
Time Line
  • 2-4 weeks
  • 4-8 weeks
Other Details
  • Rapid
  • Preserves one-half genome
  • IVF needed for sperm recovery
  • Recommended for single mutations on a common inbred background
  • Preserve donor genotype
  • Recovery is simple and the time is short
  • Recommended for homozygous, multiple unlinked mutations, unique genetic backgrounds


Note: Wildtype females of the same genetic background will be purchased from approved vendors for heterozygous lines. Investigators needing homozygous mice or mice with multiple genetic mutations, have to provide an adequate number of homozygous females, approximately 12-15 young females per IVF (3-12 weeks old). For some homozygous lines this number of females may not generate enough embryos. If more than 2 IVF’s are needed, extra charges may be incurred. Beyond 2 IVF's, mouse purchases will be under the PI's recharge account.
- How to request services:
  • To complete process investigator must:
              - Complete Cryopreservation request form through iLabs. Indicate the original building and room location of mice, exact strain name, cage card number, DOB of each mouse and provide the required number of mice. To sign up for iLab account please click here
              - After Cryo Core receives and approves the request, then lab must submit a transfer request through RIO and reference you iLab request number -- ATTN Khalida Cryo Core
              - Make sure the strain name on the request matches the name indicated on the cage card.
Note:  All movement of mice must be coordinated through the LARC business office as an inter-facility transport.  Please click here for the shipping link.
  • Complete embryo storage records are maintained and a pdf update inventory list will be sent to the PI upon request.
  • For questions on services, please contact Khalida Sabeur ([email protected]).

  • Frozen sperm will be resuscitated by IVF and embryo transfer.  We will either purchase wild type oocyte donors of the same genetic background or the investigator has to provide homozygous oocyte donors of the same strain (10-12 females per IVF).


  • Frozen embryos will be recovered, cultured and transplanted into the oviduct or uterus of a pseudopregnant recipients.


  • If sperm or embryos were frozen at another institution:
                  - We will only receive straws or vials from mice in a specific pathogen-free (SPF) facility.
                  -A thawing protocol and specific information about embryo stage and sperm quality need to be submitted.
                  - A minimum of 2 straws or vials per strain should be shipped to the Cryo Core in liquid nitrogen dry shipper (please include recharge account and shipping address for return of the dry shipper).
                 - the Cryo Core can provide a dry shipper. It must be returned to the Cryo Core within a week. PIs will be charged $1,200.00 for replacement of the shipper if it is not returned to the Cryo Core.
  • Steps involved:
  1. The investigator submits a Resuscitation request form through RIO.
  2. Cryo Core reviews the completed form and approves it. Requests will not be processed if a valid recharge code is not provided (Please provide the speed type number).
  3. Upon receipt of the request form the Cryo Core Staff will contact you to ask to you to initiate the transfer of mice to PSB or frozen sample to the designated Cryopreservation Core location.
  4. Cryo Core staff will update you on the date the job is scheduled and again upon completion.
  5. Cryo Core will notify you if there are any problems.




Time Line
Sperm Cryo No Test Thaw-culture (2 males)
2-4 weeks
Sperm cryo and Test Thaw-culture
2-4 weeks
Sperm Resuscitation*
9-12 weeks
Embryo Cryo (2 IVF's)
4-8 weeks
Embryo Resuscitation*
8-10 weeks
In Vitro Fertilization
8-12 weeks
Storage vials (per vial per year)
Billed twice a year (Jan. and July)
* For resuscitation included per diem about 8 weeks.



  • There are different levels of quality control:
            - Sperm Cryopreservation: One vial from each strain is thawed for motility and viability.  The recovery of sperm by IVF to blastocyst stage or to live pups will be at extra charge to cover the IVF procedure.


            - Embryo Cryopreservation: A straw from the strain being cryopreserved (SW) will be cultured to determine the proportion that develop to the blastocyst stage.  In addition, the embryos (in C57BL6J) will be transferred into pseudopregnant females to produce live born offsprings.

            - Sperm and Embryos: They are properly stored in liquid phase of LN2 in LARC facility. The containers are correctly identified using a color-coded system and a standard format which includes strain and PI name, cryopreservation date, number and stage of embryos, and ID number.
  • Records: Complete animal, sperm, and embryo records are maintained in a secure database.



  • The Cryo Core handles tracking, storage and inventory of frozen samples.


  • Tanks: All tanks are continuously monitored by alarm systems and undergo regular daily visual inspections.


  • Storage fees are separate from service fees noted above.