Freezing extender II (Tris II[8]) was added 1:1 (v:v) so the final diluent contained 199.98 mM Tris, 64.72 mM citric acid, and 55.50 mM fructose, supplemented with 20% egg yolk (v:v), 6% glycerol (v:v), 1 mM sodium pyruvate, and 0.375% Equex STM paste (Equex STM; Nova Chemical Sales Inc., Scituate, MA, USA).