Interpretive Summary: Effects of hempseed cake on ruminal fermentation parameters, nutrient digestibility, nutrient flow, and nitrogen balance in finishing steers

By: Thomas M Winders, Bryan W Neville, Kendall C Swanson

This experiment evaluated the effects of dietary inclusion of hempseed cake or dried corn distillers grains plus solubles on ruminal fermentation parameters, organic matter (OM) intake, total tract nutrient digestion, and nitrogen (N) balance in steers fed finishing diets. Steers were assigned to one of three dietary treatments (no byproduct [CON], 20% dried corn distillers grains plus solubles [DDGS], or 20% hempseed cake [HEMP]; dry matter basis). Hempseed cake had greater acid detergent fiber concentrations, which resulted in greater acid detergent fiber flow to the small intestine and reduced total tract organic matter digestibility in steers fed the HEMP diet than in steers fed the DDGS or CON diets. Steers fed the HEMP diet had greater ruminal and total tract N digestibility, and greater ruminal ammonia concentrations than steers fed DDGS or CON diets, suggesting that the crude protein in hempseed cake is degraded to a greater extent in the rumen and total tract. Although inclusion of hempseed cake decreased total tract OM digestibility compared with dried corn distillers grains or no byproduct, the observed greater ruminal and total tract N digestibility suggest that it could be a useful alternative feed ingredient for finishing cattle diets.