The technical solution covers the procedure for the laboratory determination of the structural variants in five genes of the TLR group that participate in the early immunity against the causal agents of the bacterial diseases of cattle. The area of the method can be generally denoted as the veterinary DNA diagnostics. The design of the set of reactions is derived from the general technique of primer extension which exploits the first step in the enzymatic synthesis of the complementary strand of DNA for the determination of the type of nucleotide. The framework for the design of the procedure was the bioinformatic and population-wide estimate of the variability in the immunity genes of the TLR family in the milk breeds of the Czech Red and the Czech Red Pied cattle. In the second part of the protocol development, the design of the genotyping primers and the optimization of the genotyping reactions was performed. The reaction panel is aimed at the genetic polymorphisms with diagnostic value (the so-called tagSNPs) for the determination of the remaining polymorphisms. The presence of the latter is subsequently simply derived. In this way, the reaction set allows for the determination of all variants of the antibacterial TLR genes present in the given population with a minimum number of genotyping reactions required. The labour and financial costs of the method are significantly reduced by multiplexing 5- 6 reactions to be performed in parallel.