Morphological and structural changes in bone marrow of piglets which were immunized with produced in the Republic of Belarus SPS vaccine (against salmonellosis (Salmonella), pasteurellosis (Pasteurella) and streptococcus) in combination with immunostimulants and without them were analyzed in the conditions of the Republic of Belarus. Piglets of the first group were vaccinated against salmonellosis, pasteurellosis and streptoccocusis by SPS vaccine. Piglets of the second group were vaccinated by SPS vaccine with vitamin C. Piglets of the third group were vaccinated by SPS vaccine with immunotstimulant sodium thiosulphate. The fourth (control) group of animals was administrated with normal saline. Animals were immunized twice, intramuscularly with 7 day interval in dose of 4 ml (primary), and 5 ml (secondary). Vitamin С was administrated in dose of 0,05g per head. Sodium thiosulfate was administrated in combination with the vaccine in 30% concentration. Alongside with myelogram there were derived formulas of different cell groups of bone marrow: leucoerythroblastic index; intramedullary index of neutrophil maturity; intramedullary index of eosinophile maturity. Detailed myelogram of piglets on the 14-th day after the second immunization was presented. Research results showed that in all groups of vaccinated animals there was noted the activation of myeloblastic hematogenesis and decreasing of erythropoeisis. Piglet immunization was accompanied by strengthening of myeloblastic hematogenesis, increased number of lymphocytes and plasma cells in bone marrow

Influence of potassium orotate on hematological, immunomorphological indexes and and marrowy myelopoiesis of broiler chickens in the process of oral associated immunization against infectious bronchitis and poultry Newcastle disease was investigated in the conditions of the Republic of Belarus. There were studied 60 broiler chickens divided into 3 groups: one control group and two experimental ones. Research results established that potassium orotate application in combination with associated poultry immunization against infectious bronchitis and Newcastle disease increased the number of leucocytes and the volume of adenoid tissue as well as raised the lymphocytes density in thymus and bursa of Fabricius. In the bone marrow aspirates in 7 days after immunization in the control group there was stated the increasing of basophilic myelocytes number in comparison with the second experimental group. In 14 days in the control group there was noted the increasing of a total number of basophiles. In 21 days after immunization there were stated no considerable changes in the composition of basophil cells in the experimental groups. Research results showed that potassium orotate intensively stimulated the development of plasmocytic reaction in the conditions of multipartial immunization

In the conditions of the Republic of Belarus there was realized a morphological study of bone marrow aspirates at different terms chicken of immunization against Gumboro disease which made it possible to analyze the state of immune system for the objective evaluation of immunological status. Research results showed that chicken immunization with a national liquid chick embryo viral vaccine produced on the basis of KMIehV-13 strain against Gumboro disease (infectious bursal disease) promoted the development of immunomorphological remodeling of bone marrow. Application of immunostimulants Alveozan and Nukleovit for poultry vaccination caused more expressed changes revealing in statistically reliable increasing of total number of myeloblastic cells in the majority of cases by means of increasing of immature cells, and then mature cells of granulocytic series, as well as quantity of lymphocytes and plasmacytes