Vasylieva T. Scientifically-experimental substantiation of immunogenic effectiveness of the vaccine «Metakol» against colibacteriosis of cattle

Dissertation work is devoted to the study of natural and specific protection of newborn animals through maternal immunity by immunization of cows and heifers in the last stages of pregnancy and further providing a high-level immunity against escherichiosis in calves after administrating vaccine to the 10 day old animals. The results of morphological, cultural, fermentative and biological properties of tested cultures of E. coli were presented, and it was evaluated the degree of pathogenicity and immunogenicity of bacterial cultures with inbred white mice and the virulent and highly immunogenic strain of Escherichia for designing vaccines «Metakol» against animal colibacteriosis was selected. The laboratory control sample of experimental vaccines were tested for appearance, pH, residual amount of formaldehyde, safety, toxicity, completeness of inactivation, the absence of bacterial contamination by microorganisms and microscopic fungi, immunogenic efficacy and this results presented in the dissertation. The shown results of evaluation of immunological restructuring of the body of heifers after administrating the vaccine test samples. It was carried out the comparative analysis of maternal immunity indexes in the blood of 10 day old calves derived from immunized animals and intact control animals were presented. The comparative analysis of test group of suckling calves obtained from vaccinated and unvaccinated cows and calves vaccinated at 10 days’ age was carried out for hematological indexes, immune cells, indicators opsonic phagocytosis tests, total protein content, γ-globulins fraction and heterophilic agglutinins. It was substantiated the economic efficiency of the applying of experimental sample of vaccines «Metakol» against colibacteriosis for the animals and cost calculation for conducting of the preventive vaccination in a livestock enterprise was presented.