College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China.
College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China.
Animal. 2021 Mar;15(3):100013. doi: 10.1016/j.animal.2020.100013. Epub 2021 Feb 6.
Wet corn gluten feed (WCGF) is a high moisture feed containing rapidly digestible, non-forage fiber and protein. The objective of this study was to investigate the effect of substituting WCGF and corn stover for alfalfa hay in total mixed ration (TMR) silage on lactation performance and nitrogen balance in dairy cows. Nine multiparous Holstein dairy cows (BW = 532 ± 28.9 kg and day in milk = 136 ± 5.6 d; mean ± SD) were used in a replicated 3 × 3 Latin square design with 21-d periods (14 d of diet adaption and 7 d of sample collection). Groups were balanced for parity, day in milk, and milk production and consumed one of three treatment diets during each period. The treatment diets were fed as TMR and contained similar concentrate mixtures and corn silage but different proportions of roughage and WCGF. The three treatments were: (1) 0% WCGF, 0% corn stover, and 22.1% alfalfa hay (0% WCGF); (2) 6.9% WCGF, 3.4% corn stover, and 11.8% alfalfa hay (7% WCGF); and (3) 13.3% WCGF, 4.9% corn stover, and 3.9% alfalfa hay (13.3% WCGF). Compared to the 0% WCGF diet, the cows fed the 7% and 13.3% WCGF diets had a higher milk yield and concentration of milk fat, protein, lactose, and total solids. Effective degradability of DM was higher in the cows fed the 7% and 13.3% WCGF diets than it was with the 0% WCGF diet. Cows fed the 13.3% WCGF had a higher CP effective degradability and a lower rumen undegraded protein than cows fed the 0% WCGF diet. The concentration of ruminal volatile fatty acids and ammonia-N was higher in cows fed the 7% and 13.3% WCGF diets than cows fed the 0% WCGF diet. The fecal N was lower in cows fed the 7% and 13.3% WCGF diets than it was in cows fed the 0% WCGF diet. Milk N secretion and milk N as a percent of N intake were higher in cows fed the 13.3% WCGF diet than cows fed the 0% and 7% WCGF diets. In conclusion, it appears that feeding a TMR silage containing WCGF and corn stover in combination, replacing a portion of alfalfa hay, may improve lactation performance and nitrogen utilization for lactating dairy cows.
湿玉米蛋白粉（WCGF）是一种高水分饲料，含有易消化的非纤维饲料和蛋白质。本研究的目的是研究用 WCGF 和玉米秸秆替代苜蓿干草在全混合日粮（TMR）青贮中的效果对奶牛泌乳性能和氮平衡的影响。
9 头经产荷斯坦奶牛（BW=532±28.9kg，泌乳天数=136±5.6d；均值±SD）采用 3×3 拉丁方设计重复 3 次，每个周期 21d（14d 适应期和 7d 采样期）。组间按胎次、泌乳天数和产奶量平衡，在每个周期内饲喂三种处理日粮之一。处理日粮作为 TMR 喂养，含有相似的浓缩物混合物和玉米青贮，但粗饲料和 WCGF 的比例不同。三种处理方法如下：（1）0%WCGF、0%玉米秸秆和 22.1%苜蓿干草（0%WCGF）；（2）6.9%WCGF、3.4%玉米秸秆和 11.8%苜蓿干草（7%WCGF）；（3）13.3%WCGF、4.9%玉米秸秆和 3.9%苜蓿干草（13.3%WCGF）。与 0%WCGF 日粮相比，饲喂 7%和 13.3%WCGF 日粮的奶牛产奶量和乳脂、蛋白质、乳糖和总固体浓度更高。饲喂 7%和 13.3%WCGF 日粮的奶牛 DM 有效降解率高于 0%WCGF 日粮。饲喂 13.3%WCGF 的奶牛 CP 有效降解率高于饲喂 0%WCGF 的奶牛，瘤胃未降解蛋白较低。饲喂 7%和 13.3%WCGF 日粮的奶牛瘤胃挥发性脂肪酸和氨氮浓度高于饲喂 0%WCGF 日粮的奶牛。饲喂 7%和 13.3%WCGF 日粮的奶牛粪便 N 低于饲喂 0%WCGF 日粮的奶牛。饲喂 13.3%WCGF 的奶牛乳氮分泌和乳氮占氮摄入量的百分比高于饲喂 0%和 7%WCGF 的奶牛。
总之，用 WCGF 和玉米秸秆组合代替部分苜蓿干草的 TMR 青贮料似乎可以提高泌乳奶牛的泌乳性能和氮利用率。
