College of Animal Sciences and Technology, Northeast Agriculture University, Harbin 150030, PR China.
College of Animal Sciences and Technology, Northeast Agriculture University, Harbin 150030, PR China.
Animal. 2024 Oct;18(10):101176. doi: 10.1016/j.animal.2024.101176. Epub 2024 May 3.
Aging reduces the nutritional value of corn grain, which may be improved by fermentation prior to use. This study investigated the effects of replacing conventional corn (CC) with aging corn (AC) and fermented aging corn (FAC) in the diets of lactating Holstein cows. Six healthy third-parity Holstein cows were used in a replicated 3 × 3 Latin square experiment with 21-day periods. Cows were fed twice and milked twice daily. The cows were randomly divided into three treatment groups: (1) CC diet: a diet with 23.6% starch in diet DM containing 24.0% conventional corn; (2) AC diet: a diet with 23.5% starch in diet DM containing 24.0% aging corn replacing conventional corn; and (3) FAC diet: a diet with 23.2% starch in diet DM containing 24.6% fermented aging corn replacing conventional corn. The diets were formulated to be isonitrogenous and contained identical roughage. The FAC treatment increased the starch digestibility compared with AC. Feeding FAC increased the concentrations of total volatile fatty acid compared with CC and AC and decreased the molar proportion of acetate compared with AC. At the family level, the relative abundance of Prevotellaceae was higher on FAC than CC. The relative abundance of Succinivibrionaceae was lower on FAC than on CC and AC. Besides, at the genera level, the relative abundance of Succinivibrionaceae_UCG_002 in the rumen was higher on AC than CC and FAC. The relative abundance of Prevotella and Ruminococcus was higher on FAC than CC and AC. The relative abundance of Succinivibrionaceae_UCG_001 was lower on FAC than CC. The Simpson index was lower on FAC than CC and AC. The FAC treatment increased the milk yield (34.0, 33.7, and 35.2 kg/d for CC, AC, and FAC group, respectively) and protein yield, and thus, energy-corrected milk production was increased, and at the same time, decreased the somatic cell score compared with CC and AC. The AC treatment increased the malondialdehyde concentration in plasma compared with CC and FAC. The concentrations in plasma of triglyceride and malondialdehyde were lower on FAC than AC. The immunoglobulin G concentration in plasma was higher on FAC than CC and AC. Overall, feeding AC resulted in decreased plasma antioxidant capacity compared with CC, whereas feeding FAC altered the relative abundance of bacteria in the rumen and improved starch digestibility, ruminal bacterial diversity, lactation performance, plasma antioxidant capacity and immune competence compared with AC in dairy cows.
玉米老化降低了玉米籽粒的营养价值，使用前发酵可以改善这一点。本研究探讨了在泌乳荷斯坦奶牛日粮中用老化玉米（AC）和发酵老化玉米（FAC）替代常规玉米（CC）的效果。采用 3×3 拉丁方试验，6 头健康的第三胎荷斯坦奶牛进行了 21 天的重复试验。奶牛每天饲喂 2 次，挤奶 2 次。奶牛随机分为三组：（1）CC 日粮：日粮 DM 中淀粉含量为 23.6%，含有 24.0%的常规玉米；（2）AC 日粮：日粮 DM 中淀粉含量为 23.5%，含有 24.0%的老化玉米替代常规玉米；（3）FAC 日粮：日粮 DM 中淀粉含量为 23.2%，含有 24.6%的发酵老化玉米替代常规玉米。日粮的设计是等氮的，含有相同的粗饲料。与 AC 相比，FAC 处理提高了淀粉消化率。与 CC 和 AC 相比，饲喂 FAC 增加了总挥发性脂肪酸的浓度，与 AC 相比降低了乙酸摩尔比例。在科水平上，与 CC 相比，FAC 上普雷沃氏菌科的相对丰度更高。与 CC 和 AC 相比，琥珀酸纤维弧菌科的相对丰度在 FAC 上较低。此外，在属水平上，与 CC 和 FAC 相比，AC 上的琥珀酸纤维弧菌属_UCG_002 的相对丰度较高。与 CC 和 AC 相比，普雷沃氏菌和瘤胃球菌的相对丰度在 FAC 上较高。与 CC 相比，FAC 上的琥珀酸纤维弧菌属_UCG_001 的相对丰度较低。与 CC 和 AC 相比，辛普森指数在 FAC 上较低。与 CC 和 AC 相比，FAC 处理增加了产奶量（CC、AC 和 FAC 组分别为 34.0、33.7 和 35.2kg/d）和蛋白质产量，从而增加了能量校正乳产量，同时降低了体细胞评分。与 CC 和 FAC 相比，AC 处理增加了血浆丙二醛浓度。与 AC 相比，FAC 处理降低了血浆甘油三酯和丙二醛浓度。与 CC 和 AC 相比，血浆免疫球蛋白 G 浓度在 FAC 上较高。总的来说，与 CC 相比，AC 处理降低了血浆抗氧化能力，而与 AC 相比，FAC 处理改变了奶牛瘤胃细菌的相对丰度，提高了淀粉消化率、瘤胃细菌多样性、泌乳性能、血浆抗氧化能力和免疫能力。
