[Complex-forming factors in the dilution of bull sperm for deep freezing]

Micro- and ultramicroelectrophoresis on Cellogel were employed to study the formation of complexes of bull's semen and the constituents of Nagaze-Niva's extender in all possible combinations. It was found that a new glycoprotein complex is formed in mixing the semen with yolk. This complex was found to bind 82 +/- 1.5 per cent of all proteins in the sample. The addition of lactose to the yolk-diluted semen was shown to lead to the dispersion of this complex into 4--5 subunits. The cation fraction of the semen plasma and glycerin were established to take no part in the complex formation. Discussed are the problems associated with the dispersion effect of lactose and the higher (twice to three times) survival rate of semen trated with extenders containing saccharides.