|Bernhard, Bryan - Texas Tech University|
|Carroll, Jeffery - Jeff Carroll|
|Dailey, Jeffery - Jeff|
|Rathmann, Ryan - Texas Tech University|
|Johnson, Brad - Texas Tech University|
Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/3/2010
Publication Date: 8/11/2011
Citation: Burdick, N.C., Bernhard, B.C., Carroll, J.A., Dailey, J.W., Rathmann, R.J., Johnson, B.J. 2011. Chromium supplementation enhances the acute phase response of steers to a lipopolysaccharide (LPS) challenge [abstract]. Journal of Animal Science. 89:A123(E-Suppl. 2).
Technical Abstract: The study examined the effect of chromium supplementation on the response of steers to an LPS challenge. Twenty crossbred steers (235±4 kg BW) received 0 ppb (Control; C) or 200 ppb chromium propionate (CHR) for 55 days. Steers were fitted with jugular catheters and rectal temperature (RT) recording devices. Blood samples were collected at 30-min intervals from -2 to 8, and at 24 hours relative to an LPS challenge (0.5 microgram/kg BW). Steers were also assigned a sickness behavior score from 1 (alert) to 5 (unresponsive) after each sample collection. Serum was isolated and stored until analyzed for cortisol and cytokines. Data were analyzed using the mixed procedure of SAS specific for repeated measures. Fixed effects included treatment, time, and their interaction. Prior to administration of LPS, CHR had greater RT (38.91±0.02 deg C) than C (38.77±0.02 deg C; P=0.002). Post-LPS RT increased in both treatments (P<0.001), with C producing a greater change in RT (0.40±0.01 deg C) than CHR (0.26±0.01 deg C; P<0.01). Sickness behavior scores did not differ between treatments pre-LPS (P>0.05). However, C had greater sickness behavior scores (1.20±0.01) than CHR post-LPS (1.15±0.01; P=0.03). Cortisol concentrations did not differ between treatments pre-LPS (P=0.68). Post-LPS cortisol concentrations increased (P < 0.01) but did not differ due to treatment (P=0.26). Concentrations of IL-4 increased post-LPS (P<0.01) but were not affected by treatment pre- or post-LPS (P=0.70 and 0.32, respectively). Treatment did not affect pre-LPS TNF-alpha and IFN-gamma concentrations (P=0.80 and 0.18, respectively). Post- LPS TNF-alpha and IFN-gamma increased, with CHR producing greater TNF-alpha and IFN-gamma (40±33 and 19±1 pg/mL, respectively) than C (29±3 and 16±1 pg/mL, respectively; P<0.01). Concentrations of IL-6 were greater in CHR (10.7±1.8 pg/mL) than C pre-LPS (4.9±1.9 pg/mL; P=0.03). Post-LPS IL-6 increased (P<0.01) and was greater in CHR (506±35 pg/mL) than C (296±37 pg/mL; P<0.01). In summary, our data suggests that chromium propionate supplementation enhances the acute phase response of steers to an LPS challenge, which may expedite recovery.