Cryopreservation of chicken semen of inbred or specialized strains

Pooled semen from several inbred special chicken strains was diluted with solutions containing glycerol or dimethylacetamide as a cryoprotectant. One-half milliliter samples in capped glass vials were frozen at 3 C/min to -35 C in a programmable freezer and stored in a nitrogen vapor tank. One vial of thawed semen was used to inseminate 4 hens by intravaginal, intrauterine, or intramagnal procedures. The intramagnal technique required minor surgery but always produced chicks in seven lines in contrast to the nonsurgical methods. Frozen semen of one strain stored for 29 weeks produced 12 to 14 chicks per vial when inseminated into 4 hens. This method, therefore, will reliably rescue gene pools from semen after long-term storage.