Brown algae of the White Sea as a promising source of fucoidan for increasing resistance in laying hens

The purpose of this study was to evaluate the effect of a feed additive from fucus algae on resistance indicators of laying hens in industrial poultry farming conditions. In the algae F. vesiculosus and A. Nodosum, it was revealed that the mass fraction of fucoidan in terms of a.d.w. is 3.92±0.12%.When assessing the effect of using a feed additive from fucus algae on resistance indicators of laying hens, it was revealed that it has an effect on white and red blood parameters, leukogram and phagocyte activity. In chickens of the experimental group, there was a tendency towards an increase in the number of erythrocytes, an increase in the color index, a tendency towards a decrease in the number of leukocytes relative to the increase in the control group, while the indicators were within the reference values, after 30 days of using the additive – in the experimental group the proportion of pseudoeosinovils increased by 50% and the proportion of lymphocytes decreased by 6% compared to the control group. After 60 days of using the supplement, this trend continues: the proportion of pseudoeosinophils increased by 22% and the proportion of lymphocytes decreased by 4% in the experimental group relative to the control group. In our opinion, this indicates a normalization of the ratio of leukocyte forms in the experimental group, and, consequently, the immune status. In addition, in the experimental group relative to the control group, there was a significant decrease in the number of eosinophils by 67%, which may indicate a lower allergic reaction of the body’s immune system. Indicators of blood phagocytosis significantly changed after 60 days of use: in the experimental group, phagocytic activity increased by 23%, which indicates a higher ability of leukocytes in the experimental group to absorb foreign bacteria, and, consequently, stronger cellular immunity compared to the control group. Thus, the use of a feed additive from fucus algae for laying hens containing fucoidan in an amount of 3.92±0.12% helps to normalize the ratio of leukocyte forms and increase blood phagocytosis rates, which significantly increases resistance in laying hens.