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Microinjection of a cell

Sperm Cryopreservation


  • Introduction
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. This service is available for both mice and rats. The only disadvantage is that live offspring must be recovered through in vitro fertilization (IVF) or intracytoplasmic sperm injections (ICSI).
  • Getting Started
    1. Before proceeding with any steps, the investigator needs to contact Kathy Krentz (kjkrentz@wisc.edu) or (608) 890-3785. 
    2. Complete a billing request form for service to be provided.
  • Mouse Sperm Cryopreservation
    1. TAF recommends freezing sperm from 3 young or proven males for each line.
    2. Arrangements are made to deliver the males to TAF lab for collection. 
    3. Sperm is collected and frozen in 20-24 vials (for 3 males). Sperm is stored in two liquid nitrogen tanks.
    4. Frozen sperm isstored in TAF. A $75.00 yearly liquid nitrogen storage fee is charged per Principal Investigator in December regardless of the number of samples stored.
  • Rat Sperm Cryopreservation
    1. TAF recommends freezing sperm from 2 young or proven males for each line.
    2. Arrangements are made to deliver the males to TAF lab for collection. 
    3. Sperm is collected and frozen in 28 straws (for 2 males). Sperm is stored in two liquid nitrogen tanks.
    4. Frozen sperm is stored in TAF. A $75.00 yearly liquid nitrogen storage fee is charged per Principal Investigator in December regardless of the number of samples stored.
        • Recovery of Mouse Strains by IVF 

        Investigators can request recovery of strains at any time. Sperm will be thawed and placed with oocytes from superovulated wildtype females via IVF. Resulting two-cell embryos will be transferred into recipients. Offspring will be transferred to the investigator at 3 wks of age, pending serology results and completion of the animal transfer form by the investigator and approval by the veterinarian from the relevant school.


        • Recovery of Rat Strains by ICSI (service under development)
        Investigators can request recovery of strains at any time. Sperm will be thawed and ICSI performed. Briefly, the sperm head is microinjected into an unfertilized oocytes from superovulated wildtype females. Resulting fertilized embry
        os will be transferred into recipients. Offspring will be transferred to the investigator at 3 wks of age, pending serology results and completion of the animal transfer form by the investigator and approval by the veterinarian from the relevant school.