Disclosed is a method for extending sorted sperm cells compromised by a sorting event comprising the steps of: subjecting a plurality of sperm cells to sorting stresses； selecting said plurality of sperm cells for a desired characteristic； establishing a protein-containing sperm cell extender having a first protein content value； adding said plurality of sperm cells subjected to sorting stresses and selected for a desired characteristic to said protein-containing sperm cell extender having a first protein content value； adding a protein-free sperm cell extender to said protein-containing sperm cell extender having a first protein content value； and reducing a total protein content to which the plurality of sperm cells are exposed to a second protein content value below said first protein content value.
