|Burton, Jeanne - MICHIGAN STATE UNIV|
Submitted to: American Dairy Science Association Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 23, 1997
Publication Date: N/A
Technical Abstract: Previous research has demonstrated significant immunomodulatory and health benefits of supplemental organic chromium (Cr) when fed to production-stressed cattle. In the present study, we tested potential direct effects of Cr (salt and chelate) on bovine leukocytes. This was done by culturing peripheral blood mononuclear cells (PBMC) from 4 cows in culture medium supplemented with 2% FBS and containing varying concentrations of Cr (0 to 1000 ppb), and by monitoring mitogen- (Con A, PWM) and antigen- (OVA) induced PBMC blastogenesis, antibody synthesis, and production of the cytokine IFN-gamma. Results showed that Cr salt: (1) reduced PWM-induced blastogenesis (50 to 1000 ppb), increased OVA-induced blastogenesis between 10 and 100 ppb, but abrogated response at 1000 ppb and had o effect on Con A-induced blastogenesis; (2) had no effect on PWM- or OVA-stimulated IgM or IgG (respectively) antibody synthesis, until 1000 ppb Cr when antibody synthesis was inhibited; and (3) enhanced IFN-gamma production (100 to 1000 ppb) PBMC stimulated for 48 h in Con A, PWM, and OVA. No direct effects of Cr chelate on PBMC function were observed.