Lv Xiaokang, Chen Liang, Zhou Chuanshe, Zhang Guijie, Xie Jingjing, Kang Jinhe, Tan Zhiliang, Tang Shaoxun, Kong Zhiwei, Liu Zixin, Du Zhiyan
CAS Key Laboratory for Agro-Ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Key Laboratory of Animal Nutrition Physiology and Metabolic Process Institute of Subtropical Agriculture, Chinese Academy of Sciences Changsha Hunan 410125 China.
College of Advanced Agricultural University of Chinese Academy of Sciences Beijing 100049 China.
Food Sci Nutr. 2023 May 15;11(6):3575-3587. doi: 10.1002/fsn3.3347. eCollection 2023 Jun.
This experiment explored the effects of different proportions of sweet sorghum silage as a substitute for corn silage on dry matter intake (DMI), milk yield, milk quality, apparent digestibility, rumen fermentation parameters, serum amino acid profile, and rumen microbial composition of dairy cows. A total of 32 mid-lactation Holstein dairy cows with similar body weights and parities were randomly divided into four treatments: 100% corn silage +0% sorghum silage (CON), 75% corn silage +25% sorghum silage (CS1), 50% corn silage +50% sorghum silage (CS2), and 25% corn silage +75% sorghum silage (CS3). The milk yield was increased (linear, = .048) as the proportion of sweet sorghum increased. Linear ( = .003) and quadratic ( = .046) increased effects were observed in milk fat as corn silage was replaced with sorghum silage. Compared with the CON diet group, the CS2 and CS3 diet groups had lower dry matter (DM) (linear, < .001), ether extract (EE) (linear, < .001), and gross energy (GE) (linear, = .001) digestibility of the dairy cows. The ruminal fluid aspartate (Asp) level decreased (linear, = .003) as the proportion of sweet sorghum increased. Linear ( < .05) and quadratic ( < .05) increased effects were observed for the contents of threonine (Thr), glycine (Gly), valine (Val), leucine (Leu), tyrosine (Tyr), and histidine (His) in rumen fluid with the replacement of corn silage with sorghum silage. Cows fed the CS3 diet had greater , and content/copy number than those fed the CON diet ( < .05). In conclusion, feeding sorghum silage as a replacement for corn silage could increase the milk yield and fat, promote the growth of rumen microbes, and provide more rumen fluid amino acids for the body and microbial utilization. We believe that sorghum silage is feasible for dairy cows, and it is reasonable to replace corn silage with 75% sorghum silage.
本试验探究了不同比例甜高粱青贮替代玉米青贮对奶牛干物质采食量（DMI）、产奶量、乳品质、表观消化率、瘤胃发酵参数、血清氨基酸谱以及瘤胃微生物组成的影响。选取32头体重和胎次相近的泌乳中期荷斯坦奶牛，随机分为4组：100%玉米青贮+0%高粱青贮（CON）、75%玉米青贮+25%高粱青贮（CS1）、50%玉米青贮+50%高粱青贮（CS2）、25%玉米青贮+75%高粱青贮（CS3）。随着甜高粱比例增加，产奶量呈线性增加（P = 0.048）。随着高粱青贮替代玉米青贮，乳脂肪呈线性（P = 0.003）和二次曲线（P = 0.046）增加。与CON日粮组相比，CS2和CS3日粮组奶牛的干物质（DM）（线性，P < 0.001）、粗脂肪（EE）（线性，P < 0.001）和总能（GE）（线性，P = 0.001）消化率较低。随着甜高粱比例增加，瘤胃液天冬氨酸（Asp）水平呈线性下降（P = 0.003）。随着高粱青贮替代玉米青贮，瘤胃液中苏氨酸（Thr）、甘氨酸（Gly）、缬氨酸（Val）、亮氨酸（Leu）、酪氨酸（Tyr）和组氨酸（His）含量呈线性（P < 0.05）和二次曲线（P < 0.05）增加。采食CS3日粮的奶牛的 、 和 含量/拷贝数高于采食CON日粮的奶牛（P < 0.05）。综上所述，用高粱青贮替代玉米青贮饲喂奶牛可提高产奶量和乳脂肪，促进瘤胃微生物生长，并为机体和微生物利用提供更多瘤胃液氨基酸。我们认为高粱青贮对奶牛是可行的，用75%高粱青贮替代玉米青贮是合理的。
