|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: Proceedings
Publication Acceptance Date: 4/15/2010
Publication Date: 8/5/2010
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]. Journal of Animal Science. 88:7(E-Suppl. 2).
Technical Abstract: Demand for arginine (Arg) is reported to increase during immune challenges. This study evaluated effects of lipopolysaccharide (LPS) and abomasal Arg infusion on nitrogen (N) metabolism and immune response of 20 ruminally cannulated steers (369 ± 46 kg BW) in a randomized block design. Each block consisted of a 14-d adaptation, 1-d blood collection, and 5-d fecal and urine collection. Steers were fed a diet (12.9% CP, 0.99 Mcal/kg NEg) at 1.5% BW. Treatments (2 × 2 factorial) were AA solutions with no Arg (-ARG) or 10 g/d Arg (+ARG), and sterile saline with no LPS (-LPS) or 1 microgram LPS (+LPS; E. coli 055:B5) per kg 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. Rectal temperature (RT) and blood samples were collected 0, 2, 4, 8, 12, and 24 h after LPS infusion on d 15. No LPS × ARG × h or LPS × ARG interactions occurred (P > 0.18). Cortisol, IL-6, and RT were greater (LPS × h, P < 0.01) for +LPS vs -LPS at 2, 4 (peak), 8 and 12 h (cortisol, IL-6). Tumor necrosis factor-alpha was greater at 2 h, and haptoglobin was greater at 24 h in +LPS vs -LPS steers (LPS × h, P < 0.01). Plasma Met, Leu, Val, Gln, and Orn of +LPS vs -LPS steers were greater (Met, Leu) or not different (Val, Gln, Orn) at 0 h, not different at 2 and 4 h, lower at 8 (all) and 12 h (Met, Val, Gln, Orn), and either not different (Met, Val, Orn) or greater (Leu, Gln) at 24 h (LPS × h, P < 0.01). Plasma Thr, Ser, Asp, Asn, and Glu were lower (LPS × h, P </= 0.02) for +LPS vs -LPS at 2 (Asn), 4, 8, 12, and 24 h (Thr, Ser, Asp, Glu). Plasma Ile and Pro were lower (LPS × h, P < 0.01) for +LPS vs -LPS at 4, 8, and 12 h (Ile). Plasma Ala was greater (LPS × h, P = 0.04) for +LPS vs -LPS at 2, 12, and 24 h. Plasma Lys, Tyr, and Trp were lower (P < 0.05) for +LPS vs -LPS, and plasma Ala, Pro, and Orn were greater (P </= 0.05) for +ARG vs -ARG. The +LPS vs -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. Abomasal infusion of Arg does not alter the effects of LPS on N metabolism.