Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 7, 1996
Publication Date: N/A
Technical Abstract: Previous findings indicate that dietary boron (B) through an effect on the inflammatory process can suppress the development of various inflammatory diseases. A series of experiments were conducted to determine the relation between dietary B and the immune response of chicks with different cholecalciferol (vit. D) status and challenged with different antigens. Day-old broiler chicks were fed a low-B (<0.17 mg boron/kg), vit. D deficient basal diet supplemented with B (0 or 3 mg/kg) and vit. D at various concentrations (0, 2.5 [Expt 3], 3.5 [Expt 1], 5.0 [Expt 2], and 15.63 ug/kg). Humoral immune responses were measured by the sheep red blood cell (SRBC) hemagglutination assay (Expts 1 and 3) or ELISA (Expt 2) and cell-mediated immune responses were measured with the delayed type hypersensitivity assay (Expts 1 and 2). Dietary B increased humoral immune responses 9 d after SRBC injection in all chicks in Expt 3 (P=0.057) and in chicks fed 15.63 ug/kg vit. D in Expt 1 (P<0.05) but not in Expt 2. Vit. D-deficiency tended to reduce (B did not affect) cell- mediated immune responses in Expt 1 (P=0.10) and Expt 2 (P=0.075). The in vitro effect of B (0, 0.02, 0.2, and 2 mmol/L) on splenocyte (isolated from chicks fed the low-B diet) proliferation co-cultured with phytohemagglutinin-A (PHA; 0, 5, and 50 mg/L) was also studied by using colorimetric or radioisotopic methods. Compared to the non-B supplemented treatment, B at 0.02 mmol/L enhanced (P<0.05) proliferation of splenocytes stimulated by PHA at 50 mg/L (by colorimetric assay), and B at 0.2 mmol/L tended to have the same effect (by radioisotopic assay); B at 2 mmol/L inhibited this stimulation (P<0.05) (by both assays). These findings indicate that dietary B modulates the immune response in the chick.