Podversich Federico, Rusche Warren C, Bird Scott L, Smith Zachary K F
Department of Animal Science, South Dakota State University, Brookings, SD 57007, USA.
Southeast Research Farm, South Dakota Agricultural Experiment Station, Beresford, SD 57004, USA.
Transl Anim Sci. 2025 Aug 19;9:txaf102. doi: 10.1093/tas/txaf102. eCollection 2025.
This experiment evaluated the effects of replacing one-third of corn grain in a finishing diet with rye grain (RG) processed using one of three processing methods. Predominately Angus steers (n = 192, initial shrunk BW = 410 ± 20.9 kg) were blocked by source and pen location and assigned to one of four dietary treatments: dry-rolled corn (DRC), unprocessed RG (UNP), dry-rolled RG (DRR) and hammer-milled RG (HMR). Steers were fed for a total of 147 d. Pen was the experimental unit (6 pens per treatment, 8 steers per pen), and data were analyzed as a randomized complete block design using three contrasts: grain type [DRC vs. (UNP + DRR + HMR)], RG processing (UNP vs (DRR + HMR), and RG processing method (DRR vs HMR). Processing RG increased ( = 0.02) apparent neutral detergent fiber digestibility (aNDFD). Dry-rolling RG increased digestibility of dry matter and organic matter (≤ 0.02) and tended (= 0.09) to increase starch digestibility compared to HMR. Dry matter intake (DMI) was unaffected by grain type ( = 0.55) and whether RG was processed ( = 0.27), but processing method affected DMI ( < 0.01; 11.5 and 12.3 kg/d for DRR and HMR, respectively). Grain type did not affect ( = 0.18) gain to feed (G:F). Rye processing tended to increase G:F by 4.4% ( = 0.08), and DRR steers tended to be 4% more efficient than HMR steers ( = 0.10; 0.146 and 0.140, respectively). Observed Net Energy for gain (paNEg) tended to be 3% greater for DRC than steers fed RG ( = 0.09) with RG processing having no effect (P = 0.17). Steers fed DRR tended to have 4.5% greater paNEg than HMR steers ( = 0.06; 1.32 and 1.26 Mcal/kg, for DRR and HMR, respectively). Rye grain processing tended to decrease dressing percentage (= 0.07) but no other effects on carcass characteristics or USDA grade distributions were observed ( ≥ 0.24). Liver abscess prevalence was unaffected by grain type ( = 0.81) and whether RG was processed ( = 0.77). However, processing method tended (= 0.08) to influence liver abscess prevalence (78.4% and 91.8% normal livers for DRR and HMR, respectively). Rye grain effectively replaced one-third of DRC in a finishing diet with minor effects on performance or feed efficiency. Processing RG tended to improve efficiency, and using dry-rolling tended to improve feed efficiency compared to hammer-milling under the conditions of this experiment.
本试验评估了用三种加工方法之一加工的黑麦谷物（RG）替代育肥日粮中三分之一玉米谷物的效果。以安格斯阉牛为主（n = 192，初始体重410±20.9 kg），按来源和栏位位置进行分组，分为四种日粮处理：干碾压玉米（DRC）、未加工的RG（UNP）、干碾压RG（DRR）和锤片式粉碎RG（HMR）。阉牛共饲养147天。栏为试验单位（每个处理6栏，每栏8头阉牛），数据采用随机完全区组设计进行分析，使用三个对比：谷物类型[DRC与（UNP + DRR + HMR）]、RG加工（UNP与（DRR + HMR））以及RG加工方法（DRR与HMR）。加工RG提高了（P = 0.02）表观中性洗涤纤维消化率（aNDFD）。与HMR相比，干碾压RG提高了干物质和有机物的消化率（P≤0.02），并倾向于（P = 0.09）提高淀粉消化率。干物质采食量（DMI）不受谷物类型（P = 0.55）和RG是否加工（P = 0.27）的影响，但加工方法影响DMI（P < 0.01；DRR和HMR的DMI分别为11.5和12.3 kg/d）。谷物类型不影响（P = 0.18）增重耗料比（G:F）。黑麦加工倾向于使G:F提高4.4%（P = 0.08），DRR阉牛的效率倾向于比HMR阉牛高4%（P = 0.10；分别为0.146和0.140）。观察到的增重净能（paNEg），DRC阉牛比饲喂RG的阉牛倾向于高3%（P = 0.09），RG加工无影响（P = 0.17）。饲喂DRR的阉牛paNEg比HMR阉牛倾向于高4.5%（P = 0.06；DRR和HMR分别为1.32和1.26 Mcal/kg）。黑麦谷物加工倾向于降低屠宰率（P = 0.07），但未观察到对胴体特征或美国农业部等级分布的其他影响（P≥0.24）。肝脏脓肿发生率不受谷物类型（P = 0.81）和RG是否加工（P = 0.77）的影响。然而，加工方法倾向于（P = 0.08）影响肝脏脓肿发生率（DRR和HMR正常肝脏的比例分别为78.4%和91.8%）。在育肥日粮中，黑麦谷物有效地替代了三分之一的DRC，对生产性能或饲料效率影响较小。在本试验条件下，加工RG倾向于提高效率，与锤片式粉碎相比，干碾压倾向于提高饲料效率。
