Abstract #226
Section: Ruminant Nutrition (orals)
Session: Ruminant Nutrition Platform Session I: Rumen Function and Health
Format: Oral
Day/Time: Monday 4:15 PM–4:30 PM
Location: Ballroom E
Session: Ruminant Nutrition Platform Session I: Rumen Function and Health
Format: Oral
Day/Time: Monday 4:15 PM–4:30 PM
Location: Ballroom E
# 226
Effect of subacute ruminal acidosis (SARA) and Saccharomyces cerevisiae fermentation products on endotoxins and interleukin-6 in blood plasma.
Lei Xu1, Junfei Guo1, Hamid Khalouei1, Ilkyu Yoon2, Ehsan Khafipour1, Jan C. Plaizier*1, 1University of Manitoba, Winnipeg, MB, Canada, 2Diamond V, Cedar Rapids, IA.
Effect of subacute ruminal acidosis (SARA) and Saccharomyces cerevisiae fermentation products on endotoxins and interleukin-6 in blood plasma.
Lei Xu1, Junfei Guo1, Hamid Khalouei1, Ilkyu Yoon2, Ehsan Khafipour1, Jan C. Plaizier*1, 1University of Manitoba, Winnipeg, MB, Canada, 2Diamond V, Cedar Rapids, IA.
Grain-induced SARA has been associated with an acute phase response and translocation of endotoxins from the digestive tract. It is assumed that the acute phase response is mediated by cytokines and that Saccharomyces cerevisiae fermentation products (SCFP) attenuate the effects of SARA. This study tested if grain-induced SARA increases the translocation of lipoteichoic acid (LTA), an endotoxin of gram-positive bacteria, and raises interleukin (IL)-6 cytokine. A total of 32 lactating Holstein dairy cows were assigned to 4 treatments in a complete randomized block design. Cows received a base TMR ration, containing 34% DM NDF and 18.6% DM starch. Treatments included control (base TMR and 140 g/d of ground corn), and 3 SCFP treatments: XPC (base TMR with 14 g/d of Diamond V Original XPC mixed in 126 g of ground corn), NTL (base TMR with 19 g/d of Diamond V NutriTek mixed in 121 g of ground corn), and NTH (base TMR with 38 g/d of Diamond V NutriTek mixed in 102 g/d of ground corn). Diets were fed from 4 wk before to 12 wk after calving. During wk 5 and 7 of lactation, SARA was induced by replacing 20% of DM of the base TMR with pellets containing 50% wheat and 50% barley. The SARA diet contained 28.2% DM NDF and 27.9% DM starch. Blood and rumen fluid samples were collected twice weekly during wk 4 (baseline), 5 (SARA 1), and 7 (SARA 2). The interaction between the effects of SARA and treatment were tested for significance. LTA was not detected in rumen fluid, but that may have been due to compounds that interfered with the assay. The interactions between the effects of SARA and SCFP on LTA and IL-6 in blood plasma were significant (P < 0.05). SARA increased this concentration from 0.66 to 0.71 ng/mL (P < 0.05) only in the cows on the control, XPC, and NTL treatments. SARA only increased (P < 0.05) the concentration of IL-6 in cows on the NTH treatment (380 vs. 569 ng/mL. Results show that grain-induced SARA increases LTA moderately, without increasing IL-6 in blood, and that NTH can reduce this increase in LTA. This increase in LTA is likely due to increased translocation of this endotoxin, and can be attenuated by LTH. The acute phase response resulting from SARA does not appear to be mediated by IL-6.
