|Carroll, Jeffery - Jeff Carroll|
|Chapman, James - Prince Agri Products, Inc|
|Welsh Jr, Thomas - Texas Agrilife Research|
|Vann, Rhonda - Mississippi State University|
|Randel, Ronald - Texas Agrilife Research|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 3/5/2012
Publication Date: 6/25/2012
Citation: Sanchez, N.C., Carroll, J.A., Chapman, J.D., Welsh Jr, T.H., Vann, R.C., Randel, R.D. 2012. Modulation of the metabolic response to an endotoxin challenge in Brahman heifers through OmniGen-AF supplementation [abstract]. Journal of Animal Science. 90:319(E-Suppl. 3).
Technical Abstract: This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the metabolic response of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183±5 kilograms) from the Texas AgriLife Research Center in Overton, TX, were separated into 2 treatment groups at weaning: 1) Control (C; n=12) and 2) OG (n=12; fed at 4 grams per 45.4 kilograms body weight) and fed for 69 days. On day 39, heifers were transported from Overton to New Deal, TX. On day 40, heifers were fitted with indwelling jugular catheters and moved into a barn with individual stalls. On day 41, heifers were challenged with LPS (0.25 microgram/kilogram bodyweight intravenously) and blood samples were collected at 0.5 hour intervals from -2 to 8 hour and again at 24 hours relative to LPS challenge (0 hour). Serum was isolated and stored at -80C until analyzed for glucose, insulin, non-esterified fatty acids (NEFA), and blood urea nitrogen (BUN). Heifer weight was also recorded at various intervals throughout the study. Heifer BW increased throughout the study (P<0.01) and was not affected by treatment (P>0.21). Pre-LPS glucose concentration was greater in OG (255.7±6.6 mg/dL) than C heifers (227.8±6.6 mg/dL; P<0.01). Glucose concentration increased post LPS (P<0.01), but was not affected by treatment with OG (P=0.36). Insulin concentration pre-and post-LPS was not affected by treatment with OG (P=0.84 and 0.89). Post-LPS insulin concentration increased (P<0.01) and peaked at 2 h post LPS. Pre-and post-LPS NEFA concentration was greater in C (0.19±0.01 and 0.39±0.01 mmol/L) than OG heifers (0.16±0.01 and 0.31±0.01 mmol/L; P<0.05), with NEFA concentration increasing post LPS (P<0.01). Pre- and post-LPS BUN concentration was also greater in C (10.2±0.2 and 10.5±0.1 mg/dL) than OG heifers (8.5±0.3 and 9.3±0.1 mg/dL; P<0.03), with BUN concentration increasing post LPS (P<0.01). These data suggest that supplementing heifers with OG altered their metabolic response by increasing available glucose prior to the LPS challenge and reducing the need for OG heifers to mobilize energy through lipolysis and proteolysis, which may have allowed for a more acute response to the challenge.