Studying of cultural, morphological and enzymatic properties of isolated from a calf strain Salmonella enteritidis was realized in the conditions of the Republic of Belarus. There was presented quantity and results of bacteriologic examinations for cattle salmonellosis realized in the district veterinary services in Belarus in course of three years. There was presented quantity and results of serovars of salmonellas isolated from the pathologic material from cattle obtained in course of three-year analysis: S. typhimurium, S. enteritidis, S. dublin, S. panama. The following enzicymatic properties of the studied strain were analyzed: glucose, sucrose, manna sugar, citrate, methyl red, Voges-Proskauer reaction, mobility, indole, sulphuretted hydrogen, and urea. Determination of antibiotic susceptibility of strain S. enteritidis was presented. Initial data for calculation LD50 was given. Research results showed that the studied microorganisms were the representatives of family Enterobakteriacea, genus Salmonella, species S. enteritidis

Studying of efficiency of application of modified scheme of hyperimmunization of bull-producers with a designer salmonella polyantigenin in comparative analysis with the production scheme of hyperimmunization was realized in the conditions of the Republic of Belarus. Research results showed that engineered polyvalent antigen for hyperimmunization of producer bulls contained in their formula the following serovariants of salmonella in 1:1 ratio: S. typhimurium 371, S. dublin 373, S. choleraesuis 370, and S. enteritidis CB. The obtained antigen was sterile, harmless and had pH 7,3. Hyperimmunization of producer bulls in the experimental scheme revealed in increasing of leukocytes quantity on 57,3 %, banded neutrophils on 86,7 %, B-lymphocytes - on 42,2 %, content of total protein - on 25,6 %, content of Ig G - on 77,8 %, lg M - on 51,6%. After the fifth administration of antigen there was stated the lowering of agglutinating activity of blood serum on 25%, content of Ig G - on 54,4%, Ig M - on 14,6 %, that indicated to the inefficiency of antigen administration and became the basis for termination of hyperimmunization cycle. Immunobiological reaction of bull-producers which were hyperimmunized by the suggested scheme differed from reaction of animals which were hyperimmunized by the production scheme: content of total protein increased on 10,1%, protein content - on 27,3 %, content of lg G - on 24,8 %, lg M - in 23,7%