The study of genetic markers and identification of new markers make the subject of an increasing number of research projects in various fields such as genetics of immunology, biochemical genetics, molecular genetics, quantitative genetics and the genetic amelioration of animals. The information provided by electrophoresis graphs has been used to determine the frequency of various categories of alleles (for the loci of pre-albumin, transferines and serum amylases), the frequency of various phenotypes and the genetic structure for each and every locus and, simultaneously, for the loci being studied. The discussion over the varieties of serum proteins was carried on for the purpose of using them as genetic markers, in order to appreciate the levels of genetic unity or diversity within the stock of swine that has been studied. A pair of simple alleles has been determined for each of the three loci. When the three loci were studied simultaneously, out of the 27 possible combinations, only 15 have been found. The sample studied has found to be genetically balanced for every of the three loci. However, when the simultaneous study has been applied, the same sample has not been found genetically balanced.