|BERNHARD, BRYAN - Texas Tech University|
|Carroll, Jeffery - Jeff Carroll|
|RATHMANN, RYAN - Texas Tech University|
|JOHNSON, BRADLEY - Texas Tech University|
Submitted to: Innate Immunity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/27/2011
Publication Date: 7/16/2012
Citation: Sanchez, N.C., Bernhard, B.C., Carroll, J.A., Rathmann, R.R., Johnson, B.J. 2012. Enhancement of the acute phase response to lipopolysaccharide (LPS) challenge in steers supplemented with chromium. Innate Immunity. 18(4):592-601.
Interpretive Summary: A collaborative effort between scientists as the Livestock Issues Research Unit and Texas Tech University was undertaken to determine the influence of chromium supplementation, supplemented as chromium propionate, on the immune status of steers in response to an intravenous challenge with endotoxin. Chromium has been demonstrated to decrease cortsiol concentrations, and thus it was hypothesized that chromium would enhance the acute innate immune response to endotoxin. Therefore, this study was designed to determine the affect of chroimum supplementation on the acute innate immune response of feedlot receiving steers to endotoxing challenge. Results from this study demonstrate that chromium can enhance the acute innate immune response to endotoxin challenge by increasing concentrations of tumor necrosis factor-alpha, interferon-gamma, and interleukin 6 above that of control steers. Additionally, steers supplemented with chromium produced a reduced rectal temperature and sickness behavior score response to endotoxin challenge. However, concentrations of cortisol did not differ between treatments. Future studies will need to determine the influence of chromium on aspects of energy and metabolism, including glucose, and insulin. These data suggest that chromium can be used as a supplement during the receiving period at a feedlot to help enhance innate immune functions and potentially expedite recovery. This information will be of interest to scientists working in the fields of innate immunity and nutritional supplementation.
Technical Abstract: The study examined the effect of chromium supplementation on the response of steers to an LPS challenge. Twenty steers received a premix that added 0 (control) or 0.2 mg/kg of chromium (KemTRACE®brandChromiumProprionate 0.04%, Kemin Industries) to the total diet on a dry matter basis for 55 d. Steers were fitted with jugular catheters and rectal temperature (RT) recording devices. Blood samples were collected relative to an LPS challenge (0.5 microgram/kg) and were also assigned sickness behavior scores. Prior-LPS, RT were greater in chromium-supplemented than control steers. Post-LPS RT increased in both treatments with control steers producing a greater change in RT than chromium-supplemented steers. Sickness behavior scores were greater in control than chromium-supplemented steers post-LPS. Cortisol concentrations did not differ between treatments pre-LPS. Post-LPS cortisol concentrations increased but did not differ due to treatment. Concentrations of IL-4 increased post-LPS but were not affected by treatment pre- or post-LPS. Treatment did not affect pre-LPS TNF-alpha and IFN-gamma. Post-LPS TNF-alpha and IFN-gamma increased, with chromium-supplemented steers producing greater TNF-alpha and IFN-gamma than control steers. Pre-LPS IL-6 was greater in chromium-supplemented than control steers. Post-LPS IL-6 increased and was greater in chromium-supplemented than control steers. These data suggests that chromium supplementation enhances the acute phase response of steers to an LPS challenge, which may expedite recovery.