Terler G, Gruber T, Hartinger T, Zebeli Q
Institute for Livestock Research, Agricultural Research and Education Centre Raumberg-Gumpenstein, Irdning-Donnersbachtal, Austria 8952.
Centre for Animal Nutrition and Welfare, University of Veterinary Medicine Vienna, Vienna, Austria 1210.
J Dairy Sci. 2025 Jun;108(6):5942-5953. doi: 10.3168/jds.2024-26060. Epub 2025 Apr 11.
Mixed silage of whole catch crops-crops grown between 2 main crops-and straw might be an alternative forage source for dairy cattle in times of forage shortage but is still understudied. This research sought to evaluate the effects of feeding mixed rye-vetch-straw silage (RVSS) in replacement of whole crop rye silage on feed intake, ECM yield, milk composition, nutrient digestibility, and metabolic variables of dairy cows. The study was a crossover trial with 10 Holstein and 4 Simmental cows (average of 593 kg BW and 53 DIM at the start of the trial) tested in 2 experimental runs of 4 wk each, whereby the last 2 wk were used for the measurements. The cows were randomly allocated to one of the 2 diets differing only in the major forage source, either RVSS (RVSS treatment) or a pure rye silage (RS treatment) as the control. The diets were fed as partial mixed rations consisting on a DM basis of 43.8% RVSS or RS, 14.6% corn silage, 14.6% meadow hay, and 27.0% concentrate mixture. The cows were additionally supplemented with 5 kg of concentrate per day. Data showed that feeding the RVSS diet tended to decrease the DMI without affecting performance (mean ECM yield: 28.4 kg/d) or the mean BW during the sampling period. Feeding the RVSS diet tended to increase dairy feed efficiency (kg ECM/kg DMI), likely due to the higher apparent total-tract OM digestibility of the RVSS diet compared with the RS diet. Furthermore, cows fed the RVSS diet spent significantly more time on rumination per kilogram of intake of physically effective NDF. Diet did not affect the concentration of glucose, BHB, urea, total protein, albumin, triglycerides, cholesterol, liver enzymes, or macro minerals in blood. Neither of the diets affected the concentration or proportion of short-chain fatty acids in the rumen fluid and feces. In conclusion, the mixed silage of catch crop and straw holds potential to replace traditional rye silage in the feeding of dairy cows yielding up to 30 kg of ECM per day. Feeding the RVSS diet enhanced the apparent total-tract OM digestibility and rumination index, without any negative effects on ECM yield, milk composition, BW, ruminal and fecal VFA concentration, or key blood variables. Future research may evaluate the potential of mixed silages of catch crops and straw in the feeding of high-producing dairy cows as a viable option to overcome shortages in forage production.
全填闲作物（在两种主要作物之间种植的作物）与秸秆的混合青贮饲料，可能是在饲料短缺时期奶牛的一种替代饲料来源，但目前仍研究不足。本研究旨在评估用黑麦-巢菜-秸秆混合青贮饲料（RVSS）替代全株黑麦青贮饲料对奶牛采食量、能量校正乳产量、乳成分、养分消化率和代谢变量的影响。该研究是一项交叉试验，10头荷斯坦奶牛和4头西门塔尔奶牛（试验开始时平均体重593千克，产犊天数53天）参与，分两个4周的试验阶段进行测试，其中最后2周用于测量。奶牛被随机分配到两种仅主要饲料来源不同的日粮之一，即RVSS（RVSS处理组）或纯黑麦青贮饲料（RS处理组，作为对照）。日粮以部分混合日粮形式饲喂，以干物质计，分别包含43.8%的RVSS或RS、14.6%的玉米青贮饲料、14.6%的草地干草和27.0%的精料混合物。奶牛每天额外补充5千克精料。数据显示，饲喂RVSS日粮有降低干物质采食量的趋势，但不影响生产性能（平均能量校正乳产量：28.4千克/天）或采样期内的平均体重。饲喂RVSS日粮有提高奶牛饲料效率（千克能量校正乳/千克干物质采食量）的趋势，这可能是因为与RS日粮相比，RVSS日粮的表观全消化道有机物消化率更高。此外，饲喂RVSS日粮的奶牛每摄入1千克物理有效中性洗涤纤维用于反刍的时间显著更长。日粮对血液中葡萄糖、β-羟基丁酸、尿素、总蛋白、白蛋白、甘油三酯、胆固醇、肝酶或常量矿物质的浓度没有影响。两种日粮均未影响瘤胃液和粪便中短链脂肪酸的浓度或比例。总之，填闲作物与秸秆的混合青贮饲料有潜力在日产30千克能量校正乳的奶牛饲养中替代传统黑麦青贮饲料。饲喂RVSS日粮提高了表观全消化道有机物消化率和反刍指数，对能量校正乳产量、乳成分、体重、瘤胃和粪便挥发性脂肪酸浓度或关键血液变量均无负面影响。未来的研究可以评估填闲作物与秸秆混合青贮饲料在高产奶牛饲养中的潜力，作为克服饲料生产短缺的一个可行选择。
