Effects of zinc-reinforced clinoptilolite on hematological parameters, IgG levels, and enzyme histochemistry in fattening lambs

The study aimed to determine the effects of zinc-reinforced clinoptilolite supplementation to the diet on selected hematological parameters, serum immunoglobulin G (IgG) concentrations, and enzyme histochemical characteristics in fattening lambs. For this purpose, 40 healthy male lambs were randomly allocated into five equal groups: control (C; n = 8), natural clinoptilolite (NC; n = 8), zinc (ZN; n = 8), natural clinoptilolite plus zinc (NCZN; n = 8), and zinc-reinforced clinoptilolite (ZNRC; n = 8). All animals were housed in individual pens, and the supplementation period continued for 42 days. Blood samples were collected before the trial (day 0) and at the end of the trial (day 42) to evaluate hematological parameters, serum IgG concentrations, and enzyme activity. Lymphocyte and monocyte percentages increased only in the ZN group at day 42 compared with day 0 (p < 0.05). Mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and hemoglobin values decreased in all experimental groups at day 42 compared with day 0 (p < 0.05). Serum IgG concentrations increased at day 42 compared with day 0 in the ZN, NCZN, and ZNRC groups (p < 0.05). Furthermore, supplementation with zinc-reinforced clinoptilolite resulted in higher serum IgG concentrations in the ZNRC group compared with the other experimental groups (p < 0.05). Alpha-naphthyl acetate esterase-positive lymphocyte ratios were not affected by the different dietary treatments in any experimental group (p > 0.05). In conclusion, zinc-containing combinations (NCZN and ZNRC) appeared to exert more pronounced effects on immune-related parameters, particularly lymphocyte percentages and serum IgG concentrations. These findings suggest that alternative nutritional strategies may be developed by utilizing the ion-exchange capacity of clinoptilolite.