University of wisconsin-madison

Procedure for Freezing Semen

  1. Resuspend sperm to 400 x 10^6/ ml ub freezing extender (CO-5)
  2. Cool to 5°C over 2 hr0.5 ml straws
  3. Package in 0.5 ml straws
    straws in styrofoam freezer, 3 cm above nitrogen
  4. Freeze 15 minutes in liquid nitrogen vapor (3 cm above liquid nitrogen)
  5. Store in canes under liquid nitrogen (tank)

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