Effect of bone marrow peptides on immunity of salmonella-vaccinated chickens

Abstract

The research findings on the effectiveness of peptides from small cattle bone marrow cells on the formation of a specific immune response against salmonellosis in broiler chickens are discussed. The chickens of the trial group vaccinated against salmonellosis were subcutaneously injected with a bone marrow preparation at a dose of 0.2 mL per individual on the first day of life. Blood samples were taken on the 7th and 14th days of life to evaluate blood hematological and immunological indices. It was found that the use of peptides led to intensification of the synthesis of immunoglobulin fractions (increase of 7.27%) (p < 0.01) compared to the control by the 14th day of the experiment), stimulation of phagocytic activity of leukocytes (increase compared to the control by 19.17% and 11.11% on the 7th and 14th days, respectively), lysozyme activity (exceeding the control values by 11.6% (p < 0.05) and 28.35% (p < 0.01) and bactericidal activity (increase by 12.43 and 17.75% compared to the control) of chicken blood serum, as well as the activation of the cellular immunity (increase of white blood count by 16.48% compared to the control values on day 14). Of particular importance is the revealed increase in the effectiveness of salmonellosis vaccination: the antibody titer in the trial group exceeded the control values by 40.85% (day 7) and 48.42% (day 14). The data obtained indicate that peptides from the bone marrow cells of small cattle increase the nonspecific resistance of chicken body, activate the humoral and cellular components of immunity and enhance the production of specific antibodies during vaccination. The research findings substantiate the expediency of using this preparation to increase the effectiveness of immunoprophylaxis of infectious diseases in poultry birds, in particular salmonella infection.