Effect of combined in ovo administration of zinc glycine chelate (Zn-Gly) and a multistrain probiotic on the modulation of cellular and humoral immune responses in broiler chickens

Abstract

The aim of the study was to determine the effect of in ovo administration of zinc-glycine chelate (Zn-Gly), and a multi-strain probiotic on the hatchability and selected parameters of the cellular and humoral immune response of chickens. The study was conducted on 1400 fertilized eggs from commercial broiler breeders (Ross x Ross 708). Material for the study consisted of peripheral blood and spleens of chicks taken 12 hours and 7 days after hatching. The results showed that both combined and single in ovo administration of the multi-strain probiotic and zinc glycine chelate significantly reduced hatchability of chicks. The flow cytometry study showed that the highest percentage of CD4+ T cells, CD4+CD25+ and high expression of KUL01 in the serum were obtained in the group supplemented with probiotic and Zn-Gly both 12 hours and 7 days after hatching. In birds supplemented with probiotic and zinc chelate, a high percentage of TCRγδ+ cells was found in serum and spleen 12 hours after hatching and in serum after 7 days. The percentage of Bu-1A+ lymphocytes in serum and spleen 12 hours and 7 days after hatching was the highest in the group supplemented with probiotic and Zn-Gly. The highest expression of CD79A was observed in the group supplemented only with zinc chelate. There were no significant differences in the percentage of CD4+ cells in the spleens of birds in the groups receiving the multi-strain probiotic at 12 hours after hatching, and after 7 days the percentage of CD4+ T cells was lower in the experimental groups than in the control group. The percentage of CD8+ cells in the serum of birds after hatching was lower in the group supplemented with multi-strain probiotic and Zn-Gly than in the control group, but reached the highest value on day 7 after hatching. The obtained results confirm the strong effect of the combined administration of a multi-strain probiotic and Zn-Gly chelate on lymphocyte proliferation and stimulation of cellular immune mechanisms in birds.