ENHANCING ANIMAL WELL-BEING, IMMUNOCOMPETENCE, AND PERFORMANCE IN SWINE AND BEEF CATTLE
Location: Livestock Issues Research
Title: The effect of yeast cell wall supplementation on the metabolic responses of crossbred heifers to endotoxin challenge
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: March 4, 2012
Publication Date: June 25, 2012
Citation: Sanchez, N.C., Young, T.R., Carroll, J.A., Corley, J.R., Rathmann, R.J., Johnson, B.J. 2012. The effect of yeast cell wall supplementation on the metabolic responses of crossbred heifers to endotoxin challenge [abstract]. Journal of Animal Science. 90:704(E-Suppl. 3).
This study examined the effect of feeding yeast cell wall (YCW) products on the metabolic responses of newly-received heifers to endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.9±2.4 kg) were obtained from commercial sale barns and transported to the Texas Tech University Beef Center. Heifers were separated into treatment groups receiving a Control Diet (C; n=8), YCW A (2.5 g/hd/d; n=8) or YCW C (2.5 g/hd/d; n=8) and were fed for 52 days. Heifers were weighed on d 0, 14, 36, 38, and 52. On day 36,heifers were fitted with indwelling jugular catheters and moved into a barn with individual stalls. On day 37, heifers were challenged intraveneously with LPS (0.5 ug/kg BW) and blood samples were collected every 0.5 hour from -2 to 8 and again at 24 hour relative to LPS challenge (0 hour). Serum was isolated and stored at -80C until analysis for glucose, insulin, non-esterified fatty acid (NEFA), and blood urea nitrogen (BUN) concentrations. Heifer weight increased from days 0-36 and from days 38-52 (P<0.01), but was not affected by treatment (P>0.32). Post-LPS YCW A (-6.0±0.9 kg) lost more weight (from days 36-38) than C (-2.4±0.9 kg) and YCW C (-4.2±0.9kg; P=0.04). Post-LPS glucose increased (P<0.001) and was less in YCW A (98.5±2.5 mg/dL) than C (105.6±2.4 mg/dL) and YCW C (109.5±2.4 mg/dL; P<0.01). Pre-LPS insulin was greater in YCW A (0.80±0.06 ng/mL) and YCW C (0.087±0.06 ng/mL) than C (0.44±0.06 ng/mL; P<0.01). Post-LPS insulin increased (P<0.01) with YCW C (0.95±0.04 ng/mL) and YCW A (0.71±0.05 ng/mL) having greater insulin than C (0.59±0.04 ng/mL; P<0.001). Pre-LPS NEFA tended (P=0.07) to be less in YCW C (0.14±0.01 mmol/L) than C (0.18±0.01 mmol/L) and YCW A (0.17±0.01 mmol/L). The difference in NEFA was significant post-LPS (0.18±0.01, 0.21±0.01, and 0.21±0.01 mmol/L respectively for YCW C, C, and YCW A). Pre-LPS BUN was greater in YCW A (8.2±0.3 mg/dL) than C (6.9±0.3 mg/dL; P=0.03). Post-LPS BUN was greater in YCW A (8.9±0.2 mg/dL) than C (8.2±0.2 g/dL) and YCW C (8.1±0.2 mg/dL; P<0.01). These data indicate that certain YCW products can enhance the energy metabolism during an immune challenge without causing lipolysis or muscle catabolism.