Use of fiber recovered from dairy manure as a roughage source in finishing beef cattle diets

Evaluate the effects of feeding fiber recov-ered from dairy cattle manure (Lignium Fiber, Lignium Corp., Boca Raton, FL) on feed intake, apparent digest-ibility, and ruminal fermentation characteristics in finish-ing beef heifers. Eight ruminally cannulated crossbred beef heifers (initial BW = 520 ± 85.5 kg) were used in an experiment with replicated, concurrent 4 × 4 Latin squares with 4 consecutive 15-d periods. How-ever, data from one heifer were not collected due to health complications. Heifers were fed 1 of 4 experimental diets that contained (DM basis) 8.0% warm-season grass hay (HAY), 8.0% wheat straw (WSTRAW), 8.0% Lignium Fi-ber (LIG), or 4% warm-season grass hay + 4% Lignium Fiber (HAY+LIG). All diets contained 46.7% dry-rolled corn, 5.3% supplement, and 40.0% wet-corn gluten feed (DM basis). Individual roughage sources were evaluated using the Penn State Particle Separator. Each period in-cluded 10 d of diet adaptation, 4 d of fecal collection, and 1 d of ruminal digesta collection. Chromic oxide was used as a marker to determine diet digestibility. Ruminal pH, concentrations of ammonia, and volatile fatty acids (VFA) were measured. When evaluated using the Penn State Particle Separator, 16%, 23%, and 94% of particles from wheat straw, warm-season grass hay, and Lignium Fiber were <4.0 mm, respectively. Intake and ap-parent digestibility of DM, OM, NDF did not differ among treatments. Intake of ADF tended to be greatest for LIG, intermediate for HAY+LIG and WSTRAW, and least for HAY. Acid detergent fiber digestibility tended to be great-est for HAY, intermediate for HAY+LIG and WSTRAW, and least for LIG. Average ruminal pH and concentra-tions of total VFA and ammonia did not differ among treatments. However, ruminal propionate and isovalerate tended to be greater for HAY, LIG, and HAY + LIG com-pared with WSTRAW. Incorporating Lig-nium Fiber into a finishing diet based on dry-rolled corn with 40% wet-corn gluten feed (DM basis) in place of hay or wheat straw did not affect DMI, apparent DM digest-ibility, or ruminal pH.