EN
Blood serum proteins from 23 mature silver foxes and 16 polar foxes were separated by horizontal polyacrylamide gel electrophoresis. In obtained electrophoregrams the following protein regions were differentiated: prealbumins (Pa), albumins (Alb), postalbumins (Poa), pretransferrins (Ptf), transferrins (Tf) and posttransferrins (Potf). It was demonstrated that the migration of proteins in the regions Pa₂, Alb, Poa₁ Ptf₂ and Tf was faster than the migration of proteins in the regions Pa₃ i Poa₃ in silver foxes in comparison with polar foxes. The differences let us suppose thus it can be stated that proteins of those regions in tested species of breeding foxes reveal genetic polymorphism.