Effect of dietary lipoic acid on metabolic hormones and acute-phase proteins during challenge with infectious bovine rhinotracheitis virus in cattle.
OBJECTIVE
To determine the effect of dietary supplemental lipoic acid (LA) on serum concentrations of metabolic hormones and acute-phase proteins of steers challenged with infectious bovine rhinotracheitis virus (IBRV).


METHODS
32 steers.


METHODS
Steers were randomly assigned to 4 treatments: negative control (NC; no LA, no IBRV challenge), control (CON; no LA, IBRV challenge), 16 mg of LA/kg of body weight (BW)/d plus IBRV challenge (LA16), and 32 mg of LA/kg of BW/d plus IBRV challenge (LA32). Following a 21-day adaptation period, CON, LA16, and LA32 steers received IBRV (2 mL/nostril [day 0]); NC steers received saline (0.9% NaCl) solution. Blood samples, nasal swab specimens, BW, and rectal temperatures were obtained 0, 1, 3, 5, 7, 14, and 21 days after challenge. Serum was analyzed for concentrations of haptoglobin, amyloid-A, leptin, and anti-IBRV antibodies.


RESULTS
Steers fed LA32 began gaining BW by day 7, whereas BW of CON and LA16 steers declined. Serum haptoglobin concentration of LA32 steers was lower than that of CON and LA16 steers on day 7. Serum neutralization titers for 30 of 32 steers were negative for anti-IBRV antibodies before challenge; however, all steers (including NCs) had antibodies on day 21.


CONCLUSIONS
Results suggested that LA supplementation augmented certain aspects of the immune response; LA32 steers had a more rapid recovery from IBRV viral challenge than did others.
Schmidt
Ty B
TB
Division of Animal Science, University of Missouri, MO 65211, USA.
Brown
Michael S
MS
Larson
Robert L
RL
Kleiboeker
Steven B
SB
Olson
K C
KC
Keisler
Duane
D
Carroll
Jeffery A
JA
Berg
Eric P
EP
D000209:Acute-Phase Proteins / Q000378:metabolism*; D000821:Animal Feed; D000818:Animals; D002417:Cattle; D004041:Dietary Fats / Q000008:administration & dosage / Q000494:pharmacology; D007241:Infectious Bovine Rhinotracheitis / Q000378:metabolism* / Q000821:virology*; D008297:Male; D008063:Thioctic Acid / Q000008:administration & dosage* / Q000494:pharmacology*; D015430:Weight Gain / Q000187:drug effects*
D000209:Acute-Phase Proteins; D004041:Dietary Fats; D008063:Thioctic Acid