PSXI-20 - Evaluation of the Effects of Hempseed Cake on Immune Parameters in Response to an Endotoxin Challenge in Finishing Steers

Abstract: Hempseed cake, a byproduct of industrial hemp and subsequent hempseed oil extraction processes, contains cannabinoids and fatty acids that could be potentially therapeutic for livestock, but little is known about the extent to which hempseed cake can influence immune response variables of cattle. An endotoxin challenge experiment using crossbred steers (n = 5; initial BW = 542 kg, SD = 40 kg) was conducted to evaluate the effects of hempseed cake treatment (HEMP) and dried corn distillers grains plus solubles treatment (DDGS; each included at 20% of diet DM in respective treatments) in comparison with a dry-rolled corn-based negative control treatment (CON) on plasma glucose, non-esterified fatty acids (NEFA), urea nitrogen (PUN), rectal temperature, twelve cytokine (IFNγ, IL-1α, IL-6, IL-8, IL-10, IL-36RA, IP10, MCP-1, MIP-1α, MIP-1β, TNFα, and VEGF-A), and amino acid concentrations at five timepoints after administration of endotoxin (lipopolysaccharide; LPS). Steers were administered LPS at 0.25 μg/kg BW, and blood was collected via jugular venipuncture before and 1, 2, 4 and 6-hours post-bolus injection. Data were analyzed as repeated measures using the MIXED procedure of SAS, and pre-bolus values was used as a covariate. A treatment by hour interaction (P = 0.04) was observed for PUN, and pre-bolus PUN was greatest (P < 0.01) in steers fed the HEMP. Plasma IL-1α, IL-36RA, and TNF-α were least (P ≤ 0.02), while IL-10 and MIP-1α tended (P ≤ 0.10) to be less in steers fed the HEMP diet. Plasma isoleucine, leucine, tryptophan, and tyrosine concentrations were greatest (P ≤ 0.04) in steers fed the DDGS diet, plasma aspartic acid and glycine concentrations were greatest (P ≤ 0.02) for steers fed the DDGS and CON diets. Overall, these data suggest that hempseed cake has potential to reduce inflammation by influencing cytokine production, but more research is needed to further understand animal growth performance and health implications.