Creation of effective and easy-to-replicate in laboratory conditions culture medium for isolation of salmonella out of water, which could make it possible to increase the safety, authenticity and efficiency of bacteriological study of aquatic medium objects, was realized in the conditions of the Republic of Belarus. In course of the numorous preliminary experiments there was developed an enrichment medium containing the following: nutrient yeast (5 g/l); potassium phosphate monosubstituted (8,6 g/l); sodium hydrate (1,4 g/l); 0,1% brilliant green solution (5 cm3/l); 0,01% solution of crystal violet (10 cm3/l); distilled water (1 l). The analyzed medium was estimated in accordance with the following propertiesd: medium sensitivity; efficiency; inhibition of bacteria growing. Research result showed that the experimental medium was more sensitive in comparison with the selenite one. Studying of the efficiency of the compared media showed that accumulation of test strains of S. enteritidis on the experimental medium was in 10E4 times higher, S. typhi – in 10E3; S. typhiniurium, S. anatum was in 10 times higher than at selenite media. The experimental studies proved that the experimental culture medium for salmonella isolation out of city water and surface water was more sensitive and easier to use than the selenite medium

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%

Results of studying of therapeutic efficiency of developed in the Republic of Belarus biological preparation of trial series against salmonellosis of animals and birds in the conditions of experimental salmonellosis of calves were presented. Research results showed that dualfold application of multivalent antitoxic serum against salmonellosis of calves, piglets and birds which was caused by association of S. Dublin, S. typhimurium, and S. enteritidis was accompanied by activation of humoral immunity. It was revealed in increasing of agglutinating activity of blood serum against S. enteritidis – in 11,5 times, against S. typhimurium – in 10,5 times, and against S. Dublin – in 10,0 times in 6 days after introduction of infection (4-th day after second application serum). Content of Ig M in blood serum calves which were treated with experimental serum increased in 2,0 times on the 6-th day after introduction of infection. Quantity of Ig G increased in 2,6 times by the 6-th day after introduction of infection. All these changes were typical for the clinical recovery of animals. Treatment efficiency of application of the analyzed serum was 75%

Experimental research on production of antigen preparation for hyperimmunization of bulls from blood of which it was possible to produce an active medical and preventive serum against cattle salmonellosis and pasteurellosis was realized in the conditions of the Republic of Belarus. There were developed four variants of antigen on the basis of the formolated aluminous concentrated vaccine against calf salmonellosis and on the basis of semiliquid aluminum hydroxide vaccine against cattle pesteurellosis. All obtained variants of associated antigen had concentration of hydrogen ions, which was close to the neutral rating; they were also sterile and safe for white mice. Associated antigen which was constructed from vaccines in the ratio of 1:1, 1:2, 1:3, and 2:3 had an ability to raise the protection of immunized experimental guinea pigs in the conditions of controlled introduction of infection with S. dublin 373 and S. tythimurium 371. Pasteurellosis component of associated antigen in 1:1 and 1:2 variants protected against death only 3 out of 5 immunized doves, both in relation to P. multocida strain N 796, and bacteria P. multocida strain N 5264. Vaccine ratio in the associated antigen 1:3 and 2:3 turned to be more immunogenically balanced: all tested doves survived after introduction of infection of broth culture P. multocida of N 796 and N 5264 strains. Experimental results showed that the associated antigen on the basis of vaccines in ratio of 1:3 was sterile, safe, active and suitable for hyperimmunization of bull producers serum against salmonellosis and pasteurellosis of calves, as well as antigen in the variant 2:3, but this ratio increased the expenses