28 Effect of Dietary Hempseed Meal on Growth Performance and Dry Matter Intake in Yearling Rough-Stock Bulls

Abstract The Association of American Feed Control Officials (AAFCO) is gathering information about the safety and efficacy hemp its derivatives as potential animal feedstuffs. Yearling rough-stock bulls (n = 38) were used in a randomized complete block design to evaluate effects hempseed meal (HSM) concentrate ingredient on growth, dry matter intake (DMI), efficiency. Bulls blocked by body weight (BW), grouped into 10 pens 3 or 4 bulls/pen), randomly assigned control supplement treatment (CON; 72.5% cottonseed meal, 14.5% soy hulls, 13% fat). Ingredients for CON because they common commercial commodities formulated match macronutrients HSM. Treatments top-dressed at 10% diet, while 90% was fed mixed ration [50% bermudagrass hay, 40% textured feed (10% CP)]. delivery, orts recorded daily. Diet samples dried calculate (DMI). Blood urea-N (SUN; VetScan Chemistry Analyzer) BW obtained days 0, 21, 42, 63. Efficiency evaluated each period using DMI average daily gain (ADG). Data analyzed GLIMMIX procedure SAS 9.4. Results considered significant P < 0.05, tendencies discussed 0.05 > 0.10. No treatment×time interaction occurred (P 0.999), ADG 0.563), interim 0.672), efficiency 0.254), SUN 0.170). Treatment did not affect (320.4 324.69 ± 121.57 kg HSM, respectively, 0.996), but increased over time (261.13 74.71 322.5 kg, initial final BW, 0.001). effect (0.73 0.84 0.13 0.680). However, decreased (1.0 0.29, 1.19 0.21 0.79 d0-21, d21-42, d42-63, 0.005). Daily resulted interaction, where HSM often consumed more DM than 0.01). Interim (7.44 1.25, 7.84 0.98, 8.18 0.82 0.0073), when combined with determine efficiency, main different ≥ 0.17). Over time, (4.91, 10.52, 11.66 12.72 0.35 mg/dL 42 63, 0.001), had greater (10.46 9.45 0.30 CON, 0.0426). These data suggest that diet perform similarly same nutrient profile standard ingredients, indicating comparable availability between treatments. Conversely, difference nitrogen metabolism treatments warrants further investigation.