Panhans Mekenzie H, Mason Katie M, Mullenix Mary K, Prevatt Chris G, Moisá Sonia J, Muntifering Russell B
The Dairy Alliance, Atlanta, GA.
Department of Animal Sciences, Auburn University, Auburn, AL.
Transl Anim Sci. 2019 Nov 9;4(1):376-384. doi: 10.1093/tas/txz171. eCollection 2020 Jan.
A 52-d winter feeding trial was conducted to determine animal performance, utilization, and economics of pearl millet (PM) baleage, sorghum × sudangrass (SS) baleage, and "Tifton 85" bermudagrass (B) hay for lactating beef cow-calf pairs. Cone (C) and open-shaped (O) rings were evaluated for potential to minimize forage wastage. The experiment was a completely randomized design with a 3 × 2 factorial arrangement of treatments for each forage type × hay ring (3 cow-calf pairs per treatment; 2 replications per treatment). Animal response measures included cow body weight (BW) change and body condition score (BCS) over the 52-d trial, initial and final calf BW, and cow milk production at the midpoint and end of the study. Forage nutritive value parameters evaluated for each forage type included ash, crude protein (CP), in vitro true digestibility (IVTD), neutral detergent fiber (NDF), acid detergent fiber, and acid detergent lignin (ADL). Forage wastage was estimated for each forage × ring treatment as the percentage of the bale weight remaining in feeding rings at the time of bale replacement. An economic evaluation of the relative costs associated with production and utilization of each forage type was calculated. There were no differences ( ≥ 0.10) in cow BW change or BCS change among forage types, between ring shapes, or an interaction observed for these response variables. Proportion of waste from PM and SS baleage was greater ( < 0.10) than for B hay, although there was no forage type × hay ring interaction or differences between O and C hay ring treatments for forage waste ( ≥ 0.10, respectively). Cow milk production and calf BW gain did not differ among forage type ( ≥ 0.10, respectively); however, beef calves in pens containing the O ring feeder weighed 6 kg more ( ≤ 0.05) than calves whose dams were fed using C rings. The economic analysis implies that it is more costly to feed warm-season annual forage baleage to cow-calf pairs than dry hay, largely due to greater costs of production, lack of difference in animal performance responses, and less utilization of baleage compared with feeding bermudagrass hay in this trial.
进行了一项为期52天的冬季饲养试验,以确定珍珠粟(PM)青贮饲料、高粱×苏丹草(SS)青贮饲料和“蒂夫顿85”百慕大草(B)干草对哺乳母牛-犊牛对的动物生产性能、利用率和经济性。对锥形(C)环和开口形(O)环进行了评估,以确定其将饲料浪费降至最低的潜力。该试验采用完全随机设计,每种饲料类型×干草环的处理采用3×2析因排列(每个处理3对母牛-犊牛;每个处理2次重复)。动物反应指标包括52天试验期间母牛体重(BW)变化和体况评分(BCS)、犊牛初始和最终体重,以及研究中期和末期母牛的产奶量。对每种饲料类型评估的饲料营养价值参数包括灰分、粗蛋白(CP)、体外真消化率(IVTD)、中性洗涤纤维(NDF)、酸性洗涤纤维和酸性洗涤木质素(ADL)。对每种饲料×环处理的饲料浪费进行了估算,以替换草捆时留在饲喂环中的草捆重量百分比表示。计算了与每种饲料类型的生产和利用相关的相对成本的经济评估。在饲料类型之间、环形状之间,或这些反应变量的交互作用中,母牛BW变化或BCS变化没有差异(≥0.10)。PM和SS青贮饲料的浪费比例高于B干草(<0.10),尽管对于饲料浪费,不存在饲料类型×干草环交互作用,且O环和C环处理之间也没有差异(分别≥0.10)。饲料类型之间的母牛产奶量和犊牛BW增加没有差异(分别≥0.10);然而,使用O环饲喂器围栏中的肉牛犊比使用C环饲喂其母牛的犊牛重6千克(≤0.05)。经济分析表明,给母牛-犊牛对饲喂暖季一年生饲料青贮料比干草成本更高,这主要是由于生产成本更高、动物生产性能反应无差异,以及在本试验中与饲喂百慕大草干草相比,青贮料利用率更低。