Rederivation



What You Will Provide What We Will Provide Regulatory Compliance Cost Assurances Timeline

Online Ordering

You will need the following information to order
  • PI name, address and contact info
  • Account Number
  • IACUC protocol number
  • Genetic background
  • Allele name
  • Age of males
  • Number of males
  • Current location of mice
  • Location to deliver clean mice to




Success Rates in Rederivation

     The core generates an average of about 16 pups per rederived strain.

rederivationsuccess


Frequently Asked Questions

What is rederivation?
      Rederivation is used to establish Specific Pathogen Free (SPF) mice. We transfer preimplantation embryos into SPF pseudopregnant recipient females. This procedure is more reliable than caesarian delivery for removal of pathogens.

Which pathogens will remain?
      The mice that we provide are as clean as mice from The Jackson Laboratory and Charles River. Our mice are Specific Pathogen-Free, and are negative for Helicobacter sp and Norovirus. If you have concerns about other pathogens and commensals, please discuss your concerns with us prior to attempting rederivation. You should be aware that most animal housing rooms at CWRU are positive for Helicobacter sp and Norovirus. If you wish to exclude these pathogens from mice you obtain from us, you will need to coordinate your rederivation efforts with the ARC management to find appropriate housing.

Which strains of mice?
      All strains of mice can be rederived, but the efficiency of the procedure depends on the robustness and fecundity of the strain. Inbred strains require larger starting numbers of mice for a reasonable chance of success.

How many mice of each sex?
      Robust strains: three superovulated, plugged females. Inbred strains: five or more superovulated, plugged females. To obtain these numbers, you will need a comparable number of individually housed stud males, and a slightly greater number of females (assume a plug rate of 75%).

What can be done to ensure success?
      The stud males must be older than 2 months of age, and less than a year old. The stud males should be experienced at mating, but rested before attempting rederivation.
     Use your males, and purchase wild type females of the appropriate strain to obtain enough young, sexually mature females. Consult with us on numbers.

What is superovulation?
     Superovulation is the forcing of the estrus cycle through timed injection of hormones, allowing us to synchronize and schedule matings. Superovulation also can lead to greater numbers of eggs in some strains.