|Carter, Boone - New Mexico State University|
|Loest, Clint - New Mexico State University|
|Gilliam, G - New Mexico State University|
|Graham, B - New Mexico State University|
|Carroll, Jeffery - Jeff Carroll|
|Hallford, Dennis - New Mexico State University|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 7/11/2010
Publication Date: 10/11/2010
Citation: Carter, B., Loest, C., Gilliam, G., Graham, B., Carroll, J.A., Collier, C.T., Hallford, D. 2010. Arginine supplementation does not alter nitrogen metabolism of beef steers during a lipopolysaccharide challenge [abstract]. 2010 American Society of Animal Science Meeting, July 11-15, 2010, Denver, CO. Journal of Animal Science. 88(E-Supplement 2):19.
Technical Abstract: Demand for Arg is reported to increase during immune challenge. This study evaluated the effects of lipopolysaccharide (LPS) and abomasal Arg infusion on N metabolism and immune response of 20 ruminally cannulated steers (369 ± 46 kg BW) in a randomized block design. Each block was 20 d and consisted of 14-d adaptation, 1-d blood collection, and 5-d fecal and urine collection. Steers were fed a diet (12.8% CP, 0.99 Mcal/kg NEg) at 1.5% of BW (DM basis). Treatments (2 x 2 factorial) were AA solutions with either no Arg (-ARG) or 10 g/d Arg (+ARG), and sterile saline containing either no LPS (-LPS) or 1 microgram LPS (+ LPS; E. coli 055:B5) per kg of BW. The AA solutions were abomasally infused (720 mL/d) from d 7 to 20; LPS solutions (100 mL) were intravenously infused (1 mL/min) on d 15. On d 15, rectal temperature (RT) and blood samples were collected at 0, 2, 4, 8, 12, and 24 h after LPS infusion. No LPS × Arg × h or LPS × Arg interactions were observed (P > 0.24). Tumor necrosis factor-alpha (TNF-alpha) and RT were greater (LPS × h, P < 0.01) for +LPS than -LPS steers at 2 (TNF-alpha peak) and 4 h (RT peak). Cortisol and IL-6 were greater (LPS × h, P < 0.01) for +LPS vs –LPS at 2, 4 (peak), 8 and 12 h. Haptoglobin was greater for +LPS vs -LPS only at 24 h (LPS × h, P < 0.01). Plasma Ala was greater (LPS × h, P < 0.01) among +LPS vs -LPS steers at 2, 12 and 24 h, but not at 0, 4, or 8 h. Plasma Met, Leu, Gln, and Orn of +LPS steers were greater (Met and Leu) or not different (Gln and Orn) at 0 h, not different at 2 and 4 h, lower at 8 and 12 h (Met, Gln, and Orn), and either not different (Met and Orn) or greater (Leu and Gln) at 24 h than -LPS steers (LPS × h, P < 0.01). Plasma Ser was lower at 4 h, whereas Ile, Val, Pro, Asp, Asn, and Glu were lower for +LPS vs –LPS steers at 4, 8, 12, and 24 h (Asp and Glu; LPS × h, P < 0.01). Plasma Lys, Thr, Tyr, and Trp were lower (P < 0.05) for +LPS than –LPS steers, and plasma Ala, Pro, and Orn were greater (P < 0.05) for steers infused with +ARG than –ARG. The +LPS steers tended to have greater (P = 0.13) urinary N excretion and lower (P = 0.11) N retention, and steers infused with Arg had greater (P < 0.01) digested N and tended to have greater (P = 0.15) N retention. Although supplementing Arg increased plasma Ala and Orn, it had negligible effects on LPS induced changes in AA metabolism.