Chinese Journal of Animal Nutrition >

2025 , Vol. 37 >Issue 11: 7997 - 8007

DOI: https://doi.org/10.12418/CJAN2025.650

RESEARCH PAPER

Effects of Different Additives and Fermentation Time on Fermentation Quality, in Vitro Digestibility and Long-Chain Fatty Acid Contents of High-Moisture Corn Silage

  • CHEN Xiao , 1 ,
  • HASI Qiqige 2 ,
  • GUO Yuping 3 ,
  • GAO Lin 3 ,
  • WANG Mei 3 ,
  • WANG Zhaoming 4 ,
  • MENG Jiahui 1 ,
  • GAO Zhixuan 1 ,
  • WANG Lei 1 ,
  • CHEN Xue 1 ,
  • YU Zhu , 1, *
Expand
  • 1 College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
  • 2 Forestry and Grassland Business Development Centre, Xianghuang Banner, Xilingol League, Inner Mongolia, Xilingol League 013250, China
  • 3 Shuozhou Junbaochen Agricultural Science and Technology Co., Ltd., Shanyin 036900, China
  • 4 National Center of Pratacultural Technology Innovation (Under Way), Hohhot 010070, China
*professor, E-mail:

Received date: 2025-04-11

  Online published: 2025-11-14

Fold

Abstract

This experiment aimed to explore the effects of different additives and fermentation time on fermentation quality, in vitro digestibility and long-chain fatty acid contents of high-moisture corn silage. The experiment used crushed high-moisture corn as raw material and designed a total of 5 groups with 3 replicates in each group. Among them, the acetic acid group (AA group) was added with 0.04% acetic acid (based on fresh samples, the same as below), the Lactobacillus buchneri group (LB group) was added with 1×106 CFU/g Lactobacillus buchneri, the potassium sorbate group (PS group) was added with 0.2% potassium sorbate, and the Lactobacillus buchneri+potassium sorbate group (LBPS group) was added with 1×106 CFU/g Lactobacillus buchneri+0.2% potassium sorbate. All the additives were dissolved in 30 mL of sterile water and evenly added to the high-moisture corn raw material. The control group (CON group) was added with the same volume of phosphate buffered saline. The mixture was sealed and fermented for 45 days, and samples were taken for analysis on days 3, 7, 20 and 45 of fermentation, respectively. The results showed as follows: 1) the interaction between additive and fermentation time had significant effects on the pH of high-moisture corn silage and the contents of lactic acid and ammonia nitrogen (NH3-N) (P<0.05). Compared with CON group, the pH in LBPS group was significantly decreased on day 45 of fermentation (P<0.05). The lactic acid content in LBPS group on days 20 and 45 of fermentation was significantly higher than that in the other groups (P<0.05). The NH3-N content on day 45 of fermentation was significantly higher than that at the other fermentation time (P<0.05), and the NH3-N content in LB group on day 45 of fermentation was significantly higher than that in the other groups (P<0.05). 2) The in vitro dry matter digestibility (IVDMD) in LB group and LBPS group was significantly higher than that in the other groups and raw material (P<0.05). 3) Compared with CON group, the contents of α-linolenic acid, eicosapentaenoic acid and n-3 polyunsaturated fatty acids in LB group were significantly increased (P<0.05). 4) Compared with CON group, the zein content in each additive group was significantly decreased (P<0.05). In conclusion, fermentation for 45 days and the addition of Lactobacillus buchneri+potassium sorbate can improve the fermentation quality of high-moisture corn silage better.

Key words： high-moisture corn; Lactobacillus buchneri; fermentation quality; in vitro digestibility; long-chain fatty acids

Cite this article

CHEN Xiao , HASI Qiqige , GUO Yuping , GAO Lin , WANG Mei , WANG Zhaoming , MENG Jiahui , GAO Zhixuan , WANG Lei , CHEN Xue , YU Zhu . Effects of Different Additives and Fermentation Time on Fermentation Quality, in Vitro Digestibility and Long-Chain Fatty Acid Contents of High-Moisture Corn Silage[J]. Chinese Journal of Animal Nutrition, 2025 , 37(11) : 7997 -8007 . DOI: 10.12418/CJAN2025.650

玉米(Zea mays L.)是反刍动物饲粮中最重要的能量饲料,在畜牧养殖业发展中已成为不可或缺的基础饲料。当前,传统养殖业难以满足畜牧业发展的需求[1],因此开发优良饲草资源是畜牧业可持续发展的关键。高湿玉米青贮饲料,即在玉米籽实水分含量为28%~35%时进行收获,经厌氧发酵而制成的饲料[2]。近年来,高湿玉米凭借其能够降低田间损耗、节省烘干和压片费用、提高淀粉消化率、储藏时间长、方便运输和贮藏以及经济效益高等[3]优势,逐渐成为研究的热点。高湿玉米青贮已被北欧国家、美国、英国等发达国家公认为是能够有效防止贮藏饲料发生霉变、减少营养物质损失的最好方法之一[4-6]。然而,高湿玉米青贮的制作与贮存过程中仍面临发酵品质的控制、贮存期间的霉变等风险[7]。因此,系统研究高湿玉米青贮饲料的发酵机理及优化策略,对于提升其作为饲料原料的应用价值具有重要意义。
脂肪酸是一种由碳、氢、氧3种元素组成的化合物,一般食物中所含的大多是长链脂肪酸[8]。高湿玉米青贮饲料能为家畜提供丰富的脂肪酸,使牛奶或肉类中长链脂肪酸的含量升高,从而增加其在人类膳食营养中的比例,改善人类健康[9-11]。但在青贮过程中,脂肪酸含量会出现降低的趋势[12];而脂肪酸尤其是不饱和脂肪酸含量的减少会导致青贮饲料营养价值的下降,进而导致畜产品质量的降低[13]。研究表明,加入乙酸和乳酸菌添加剂可以提高苜蓿青贮饲料品质[12],加入乳酸菌添加剂可以显著改善高湿玉米青贮饲料的发酵品质和营养品质[14],但添加剂对高湿玉米青贮饲料中长链脂肪酸含量的影响还不能确定。同时,我国对于添加剂改善高湿玉米发酵和营养品质方面的关注较少。因此,本研究以高湿玉米为材料,通过探究不同添加剂和发酵时间对高湿玉米青贮饲料发酵品质、体外消化率和长链脂肪酸含量的影响,旨在为我国畜禽饲料中广泛应用高湿玉米提供依据。

1 材料与方法

1.1 试验材料

本试验所用的高湿玉米(高油958)原料是在完熟期收获后,经人工脱粒,再经磨碎机破碎而得,高湿玉米营养成分含量见表1;试验所用的添加剂为中国农业大学饲草加工团队筛选的布氏乳杆菌(Lactobacillus buchneri)。
表1 高湿玉米营养成分含量

Table 1 Nutrient contents of high-moisture corn

项目Items 含量Content
干物质DM/% FM 70.26
粗蛋白质CP/% DM 8.10
淀粉Starch/% DM 69.94
中性洗涤纤维NDF/% DM 10.60
酸性洗涤纤维ADF/% DM 2.41

1.2 试验设计

试验共设计5个组,其中乙酸组(AA组)添加0.04%乙酸(鲜样基础,下同),布氏乳杆菌组(LB组)添加1×106 CFU/g布氏乳杆菌,山梨酸钾组(PS组)添加0.2%山梨酸钾,布氏乳杆菌+山梨酸钾组(LBPS组)添加1×106 CFU/g布氏乳杆菌+0.2%山梨酸钾,所有添加剂溶于30 mL无菌水中并均匀添加到高湿玉米原料中;对照组(CON组)添加等体积磷酸盐缓冲液(PBS)。样品充分混匀后装填至1 L青贮罐中,每组设置3个重复,然后密封发酵45 d。

1.3 测定指标及方法

1.3.1 发酵品质

分别于发酵第3、7、20和45天开罐取样,取25 g样品加入225 mL纯净水用榨汁机搅碎1 min,然后用4层纱布过滤得到浸出液。采用pH计(METTLER TOLEDO)测定pH;采用岛津高效液相色谱仪测定乳酸和乙酸含量[15],色谱柱为Shodex Rspak KC-811 S-DVB gel Column(300 mm×8 mm),检测器为SPD-M10AVP二极管阵列检测器,流动相为3 mmol/L高氯酸,流速为1 mL/min,检测波长为210 nm,进样量为5 μL;采用苯酚-氯酸钠比色法测定氨态氮(NH3-N)含量[16]。

1.3.2 营养成分含量

开罐后,随机取150 g左右青贮饲料样品,参照AOAC(2023)[17]方法采用烘箱烘干至恒重(温度为65 ℃,时间为48 h),用烘干后的重量减去烘干前的重量来计算干物质(dry matter,DM)含量;将烘干后的样品粉碎过1 mm筛,取过筛样品,参照AOAC(2023)[17]方法测定淀粉含量,采用凯式定氮法[18]测定粗蛋白质(crude protein,CP)含量,并采用Van Soest法[19]测定中性洗涤纤维(neutral detergent fiber,NDF)和酸性洗涤纤维(acid detergent fiber,ADF)含量。高湿玉米原料营养成分测定方法同上。

1.3.3 体外消化率

参照王莹[20]的方法测定体外消化率。于发酵第45天开罐取样,舍弃上下层约10 cm发酵质量差的饲料,称取0.5 g烘干粉碎后的高湿玉米原料和青贮饲料样品于纤维袋中(重复3次),放入DAISY Ⅱ体外模拟培养箱消化罐中,加入1 330 mL A缓冲液(10 g/L磷酸二氢钾、0.5 g/L硫酸镁、0.5 g/L氯化钠、0.5 g/L氯化钙、0.5 g/L尿素)、266 mL B缓冲液(15 g/L碳酸钠、1 g/L硫化钠)和400 mL于晨饲前采集的配备永久瘤胃瘘管的安格斯牛瘤胃液,往消化罐中持续通入二氧化碳(CO2)至厌氧条件,盖好盖子后放入体外模拟培养箱,在39 ℃下培养48 h,取出样品并用蒸馏水将纤维袋冲洗干净后烘干,测定残渣DM含量,计算体外干物质消化率(IVDMD),计算公式为:
IVDMD(%)=100×(样品DM含量-残渣DM含量)/样品DM含量。

1.3.4 长链脂肪酸含量

参照Qiu等[21]的方法采用岛津GC-2014气相色谱仪测定青贮饲料中长链脂肪酸含量。

1.3.5 醇溶蛋白含量

采用Larson等[22]的方法测定高湿玉米青贮饲料中醇溶蛋白含量。

1.4 数据统计分析

试验数据采用Excel 2016进行初步整理,然后采用SPSS 25.0软件的双因素方差分析过程分析不同添加剂和发酵时间及其交互作用对高湿玉米青贮饲料发酵品质和营养成分的影响;采用单因素方差分析过程分析不同添加剂对高湿玉米青贮饲料体外消化率和长链脂肪酸含量的影响,并采用Tukey法进行多重比较,结果以平均值和均值标准误(SEM)表示,P<0.05表示差异显著。

2 结果

2.1 不同添加剂和发酵时间对高湿玉米青贮饲料发酵品质的影响

由表2可知,添加剂与发酵时间的交互作用对高湿玉米青贮饲料pH以及乳酸和NH3-N含量有显著影响(P<0.05)。与CON组相比,LBPS组发酵第45天青贮饲料pH显著降低(P<0.05);在乳酸含量方面,LBPS组发酵第20和45天乳酸含量显著高于其他组(P<0.05);在乙酸含量方面,添加剂与发酵时间的交互作用不显著(P>0.05),AA组乙酸含量显著高于其他组(P<0.05);在NH3-N含量方面,发酵第45天NH3-N含量显著高于其他发酵时间(P<0.05),且LB组发酵第45天NH3-N含量显著高于其他组(P<0.05)。
表2 不同添加剂和发酵时间对高湿玉米青贮饲料发酵品质的影响

Table 2 Effects of different additives and fermentation time on fermentation quality of high-moisture corn silage

发酵时间
Fermentation time		 组别
Groups		 pH 乳酸
Lactic
acid/% DM		 乙酸
Acetic
acid/% DM		 氨态氮
NH3-N/
% TN




第3天Day 3		 CON 5.11bc 0.28efg 0.01 0.07c
AA 4.85def 0.03h 0.50 0.05c
LB 5.10bc 0.27efg 0.04 0.09c
PS 5.43a 0.24fgh 0.05 0.08c
LBPS 5.23ab 0.07gh 0.31 0.07c




第7天Day 7		 CON 4.92cde 0.35def 0.02 0.20c
AA 4.85defg 0.06gh 0.05 0.12c
LB 4.81defgh 0.35def 0.01 0.28c
PS 5.01cd 0.37cdef 0.00 0.12c
LBPS 4.73efghi 0.52bcd 0.01 0.21c




第20天Day 20		 CON 4.75efghi 0.61bc 0.01 0.16c
AA 4.74efghi 0.11gh 0.06 0.05c
LB 4.63ghij 0.53bcd 0.03 0.31c
PS 4.63ghij 0.51bcde 0.08 0.20c
LBPS 4.54ij 1.06a 0.09 0.27c




第45天Day 45		 CON 4.64fghij 0.54bcd 0.04 0.94bc
AA 4.62hij 0.24fgh 0.10 1.64bc
LB 4.48jk 0.67b 0.02 3.98a
PS 4.49jk 0.42cdef 0.01 2.12b
LBPS 4.30k 1.22a 0.04 1.37bc
均值标准误SEM 0.040 0.044 0.026 0.306
组别Groups
CON 4.86 0.44ab 0.15c 0.34
AA 4.77 0.11c 0.65a 0.46
LB 4.75 0.46ab 0.19c 1.16
PS 4.89 0.38bc 0.16c 0.63
LBPS 4.70 0.72a 0.40b 0.47
发酵时间Fermentation time
第3天Day 3 5.15a 0.18c 0.19b 0.07b
第7天Day 7 4.86b 0.33bc 0.22b 0.18b
第20天Day 20 4.66c 0.56ab 0.38ab 0.20b
第45天Day 45 4.51d 0.62a 0.46a 2.01a
显著性Significance
添加剂Additive NS *** *** NS
发酵时间Fermentation time *** *** *** **
添加剂×发酵时间Additive×fermentation time *** *** NS **

同列数据肩标无字母或相同字母表示差异不显著(P>0.05),不同字母表示差异显著(P<0.05)。NS表示不显著(P>0.05),“*”、“**”和“***”分别表示P<0.05、P<0.01和P<0.001。表3同。

In the same column, values with no letter or the same letter superscripts mean no significant difference (P>0.05), while with different letter superscripts mean significant difference (P<0.05). NS mean not significant (P>0.05), and “*”, “**” and “***” mean P<0.05, P<0.01 and P<0.001, respectively. The same as Table 3.

2.2 不同添加剂和发酵时间对高湿玉米青贮饲料营养成分含量的影响

由表3可知,不同添加剂以及添加剂与发酵时间的交互作用对高湿玉米青贮饲料营养成分含量无显著影响(P>0.05);发酵时间对高湿玉米青贮饲料DM、淀粉、NDF和ADF含量有显著影响(P<0.05),对CP含量无显著影响(P>0.05)。随着发酵时间的延长,高湿玉米青贮饲料DM、NDF和ADF含量逐渐降低,淀粉含量逐渐升高。
表3 不同添加剂和发酵时间对高湿玉米青贮饲料营养成分含量的影响

Table 3 Effects of different additives and fermentation time on nutrient contents of high-moisture corn silage

发酵时间
Fermentation time		 组别
Groups		 干物质
DM/
% FM		 粗蛋白质
CP/
% DM		 淀粉
Starch/
% DM		 中性洗
涤纤维
NDF/% DM		 酸性洗
涤纤维
ADF/% DM




第3天Day 3		 CON 72.29 8.16 68.46 8.59 2.18
AA 73.71 8.07 68.06 8.35 2.28
LB 73.44 8.12 70.56 8.31 2.14
PS 72.97 8.15 67.17 8.06 2.16
LBPS 72.25 8.07 66.60 8.50 3.01




第7天Day 7		 CON 71.43 8.19 68.69 7.00 1.92
AA 71.32 8.04 68.45 7.10 1.92
LB 71.64 8.10 68.08 7.78 1.99
PS 72.02 8.09 70.18 7.18 1.76
LBPS 71.97 9.68 69.30 6.73 1.64




第20天Day 20		 CON 70.31 8.28 72.38 7.08 1.73
AA 71.33 8.15 71.23 6.83 1.71
LB 70.76 8.25 71.91 6.58 1.78
PS 71.04 8.22 73.43 6.80 1.53
LBPS 71.00 7.80 70.53 6.86 1.73




第45天Day 45		 CON 69.73 8.28 71.59 6.66 1.87
AA 70.89 8.13 69.82 6.68 1.68
LB 70.28 8.14 71.42 6.47 1.86
PS 70.43 8.09 70.25 6.95 1.82
LBPS 72.37 8.22 70.26 6.80 1.73
均值标准误SEM 0.415 0.374 1.366 0.252 0.008
组别Groups
CON 70.94 8.23 70.28 7.33 1.93
AA 72.01 8.10 69.39 7.24 1.90
LB 71.53 8.15 70.49 7.29 1.95
PS 71.61 8.14 70.25 7.25 1.82
LBPS 71.90 8.49 69.17 7.22 1.99
发酵时间Fermentation time
第3天Day 3 72.93a 8.12 68.17c 8.36a 2.36a
第7天Day 7 71.84b 8.42 68.94bc 7.16b 1.85b
第20天Day 20 70.89c 8.18 71.90a 6.83bc 1.67b
第45天Day 45 70.74c 8.17 70.67ab 6.71c 1.79b
显著性Significance
添加剂Additive NS NS NS NS NS
发酵时间Fermentation time *** NS *** *** ***
添加剂×发酵时间Additive×fermentation time NS NS NS NS NS

2.3 不同添加剂对高湿玉米青贮饲料体外消化率的影响

如图1所示,不同添加剂对高湿玉米青贮饲料IVDMD有显著影响(P<0.05),其中LB组和LBPS组IVDMD较高,显著高于其他组和原料(P<0.05);原料IVDMD最低,显著低于各青贮饲料组(P<0.05)。
图1 不同添加剂对高湿玉米青贮饲料体外消化率的影响

数据柱形标注不同字母表示差异显著(P<0.05)。图2同。

Fig.1 Effects of different additives on in vitro digestibility of high-moisture corn silage

Value columns with different letters mean significant difference (P<0.05). The same as Fig.2.

2.4 不同添加剂对高湿玉米青贮饲料长链脂肪酸含量的影响

由表4可知,不同添加剂对高湿玉米青贮饲料反油酸甲酯、α-亚麻酸和二十碳五烯酸含量有显著影响(P<0.05)。与CON组相比,LBPS组反油酸甲酯含量显著降低(P<0.05),LB组α-亚麻酸和二十碳五烯酸含量显著提高(P<0.05)。此外,与CON组相比,LB组n-3多不饱和脂肪酸显著提高(P<0.05),AA组和LB组n-6多不饱和脂肪酸/n-3多不饱和脂肪酸值显著降低(P<0.05)
表4 不同添加剂对高湿玉米青贮饲料长链脂肪酸含量的影响

Table 4 Effects of different additives on long-chain fatty acid contents of high-moisture corn silage

项目
Items		 组别Groups 均值标准误
SEM		 P值
P-value
CON AA LB PS LBPS
十三烷酸C13∶0/% 0.08 0.12 0.16 0.15 0.20 0.659 0.491
十四碳烯酸C14∶1,n-5/% 0.04 0.06 0.10 0.07 0.15 0.060 0.458
棕榈酸C16∶0/% 13.99 13.77 16.01 14.2 15.93 1.063 0.151
反油酸甲酯C18∶1,n-9t/% 0.06a 0.06a 0.10a 0.10a 0.00b 0.025 0.015
顺油酸甲酯C18∶1,n-9c/% 36.93 35.69 31.34 36.28 33.96 2.959 0.388
反亚油酸C18∶2,n-6t/% 0.04 0.06 0.04 0.07 0.07 0.048 0.972
顺亚油酸C18∶2,n-6c/% 44.04 44.34 44.89 42.82 42.95 2.489 0.896
γ-亚麻酸C18∶3,n-6/% 0.40 0.47 0.47 0.45 0.48 0.053 0.563
α-亚麻酸C18∶3,n-3/% 0.24b 0.23b 0.35a 0.26ab 0.32ab 0.036 0.044
二高-γ-亚麻酸C20∶3,n-6/% 0.11 0.13 0.20 0.20 0.21 0.039 0.079
花生四烯酸C20∶4,n-6/% 0.07 0.09 0.25 0.21 0.15 0.068 0.390
二十碳五烯酸C20∶5,n-3/% 0.09b 0.13ab 0.25a 0.11b 0.05b 0.053 0.034
脂肪酸FA/(g/kg) 54.79 44.61 25.57 33.41 32.14 12.540 0.225
饱和脂肪酸SFA/% 17.38 17.65 20.48 18.27 20.37 1.518 0.181
多不饱和脂肪酸PUFA/% 45.15 45.92 47.03 44.53 44.66 2.533 0.849
单不饱和脂肪酸MUFA/% 37.22 36.08 31.92 36.77 34.45 2.844 0.388
单不饱和脂肪酸/饱和脂肪酸MUFA/SFA 2.14 2.05 1.57 2.02 1.74 0.248 0.197
n-3多不饱和脂肪酸n-3 PUFA/% 0.33b 0.53ab 0.76a 0.50b 0.46b 0.109 0.031
n-6多不饱和脂肪酸n-6 PUFA/% 44.81 45.39 45.39 44.03 44.20 2.506 0.893
n-6多不饱和脂肪酸/n-3多不饱和脂肪酸
n-6 PUFA/n-3 PUFA		 136.78a 88.38b 61.49b 93.80ab 33.53ab 20.249 0.044

同行数据肩标无字母或相同字母表示差异不显著(P>0.05),不同字母表示差异显著(P<0.05)。

In the same row, values with no letter or the same letter superscripts mean no significant difference (P>0.05), while with different letter superscripts mean significant difference (P<0.05).

2.5 不同添加剂对高湿玉米青贮饲料醇溶蛋白含量的影响

如图2所示,不同添加剂对高湿玉米青贮饲料醇溶蛋白含量有显著影响(P<0.05)。与CON组相比,各添加剂组醇溶蛋白含量显著降低(P<0.05),且LBPS组最低。
图2 不同添加剂对高湿玉米青贮饲料醇溶蛋白含量的影响

Fig.2 Effects of different additives on zein content of high-moisture corn silage

3 讨论

3.1 不同添加剂和发酵时间对高湿玉米青贮饲料发酵品质的影响

青贮饲料的pH被认为是衡量发酵品质的重要指标。一般认为,pH小于4.2的青贮饲料质量良好[23]。本研究中,各组高湿玉米青贮饲料pH均高于4.2,最低为4.3。研究表明,由较高DM含量发酵而成的青贮饲料pH总是高于4.2,这是因为DM含量的增加会导致微生物数量的减少,尤其是梭状芽孢杆菌[24]。根据Cherney等[25]的研究,DM含量低的青贮饲料发酵质量可以用pH评估,但不适用于DM含量高的青贮饲料。对于DM含量较高的青贮饲料,需要综合考虑DM损失、微生物数量以及NH3-N含量来进行判断[26]。本研究中,高湿玉米青贮饲料的pH值略高,这与其较高的DM含量密切相关。乳酸等有机酸的含量同样是反映发酵品质的重要指标,乳酸菌利用碳水化合物产生的乳酸是青贮饲料发酵过程中pH下降的主要原因。本研究中,高湿玉米青贮饲料乳酸含量随着发酵时间的延长而提高,LBPS组发酵第20和45天乳酸含量显著高于其他组;LBPS组发酵第3天乳酸含量低于CON组、LB组和PS组,而乙酸含量却高于上述3组,这是因为添加山梨酸钾在发酵初期抑制了产乳酸菌的生长,导致乳酸含量较低,同时由于布氏乳杆菌异型发酵产生的乙酸使青贮饲料中乙酸含量升高[27]。LBPS组发酵第20和45天乳酸含量迅速升高且显著高于其他组,这可能是因为其他组在发酵前20 d的底物浓度较低,导致后续阶段乳酸菌可利用的底物减少,进而造成乳酸合成速率降低、最终产量下降。同时,由于山梨酸钾的抗真菌活性可以抑制酵母菌活动,这为乳酸菌在发酵初期保留了更多的发酵底物。本试验与Wang等[28]的研究结果相同。NH3-N是判断青贮饲料中氨基酸和蛋白质分解程度的指标。本研究中,随着发酵时间的延长,高湿玉米青贮饲料NH3-N含量也随之升高,LB组发酵第45天NH3-N含量显著高于其他组,这是由于青贮过程中微生物的作用将植物蛋白质降解为多肽和游离氨基酸,随后青贮微生物对氨基酸的脱氨作用导致NH3-N的积累。同时,玉米胚乳中富含丰富的醇溶蛋白,随着发酵时间的延长,醇溶蛋白的降解可能是青贮饲料NH3-N含量升高的原因,LB组NH3-N含量最高则说明布氏乳杆菌能很好地降解高湿玉米中的醇溶蛋白[29]。

3.2 不同添加剂和发酵时间对高湿玉米青贮饲料营养成分含量的影响

适宜的DM含量是保证青贮饲料发酵品质的一项重要指标,如何减少青贮饲料中DM的损失具有重要的意义。本研究中,不同添加剂对高湿玉米青贮饲料DM含量无显著影响,但随着发酵时间的延长,DM含量显著逐渐降低,这是因为青贮发酵过程中的有氧和厌氧阶段植物呼吸作用以及微生物呼吸作用共同导致DM含量少量减少[30],本研究中DM的损失在研究报道中的正常范围之内,属于正常现象[31]。

3.3 不同添加剂对高湿玉米青贮饲料长链脂肪酸含量的影响

长链脂肪酸是机体获取能量的主要来源之一,一些多不饱和脂肪酸还具有调节心脏功能、增强记忆力和保护人体防御系统等功能[9]。由于脂肪酸对人类健康和产品质量的影响,近几十年来,动物产品中的脂肪酸组成越来越受到人们的关注,而肉类产品的健康在很大程度上与其脂肪含量和脂肪酸的组成有关[32]。研究表明,晾晒会导致青贮中大量不饱和脂肪酸含量减少[33],而高湿玉米不需经过晾晒便可直接进行青贮,这可能是其不饱和脂肪酸含量高的原因。同时,奶牛摄入含有大量多不饱和脂肪酸的饲粮会导致产生的乳脂中不饱和脂肪酸与饱和脂肪酸的比例变高[34]。因此,高湿玉米可以作为反刍动物饲粮中很好的不饱和脂肪酸来源。本试验中,在高湿玉米青贮饲料所有长链脂肪酸中,顺亚油酸的占比最高,这是因为玉米比其他牧草含有更高的亚油酸,同时其亚油酸约有60%储存在玉米籽实中[35]。同时,与CON组相比,LB组α-亚麻酸、二十碳五烯酸和n-3多不饱和脂肪酸含量显著提高。柯文灿[36]研究发现,添加有机酸和乳酸菌的复合添加剂可以提高紫花苜蓿青贮饲料不饱和脂肪酸含量;研究表明,添加苹果酸、柠檬酸和植物乳杆菌及其混合物可有效提高紫花苜蓿青贮饲料的发酵品质,限制蛋白质水解,并改善青贮的脂肪酸组成[37],这可能是受青贮过程中微生物的影响,同时植物酶在这一过程中也同样起着重要作用,能进行脂肪酸之间的转化,优化脂肪酸之间的比例。

3.4 不同添加剂对高湿玉米青贮饲料体外消化率的影响

体外消化率是反映青贮饲料饲用价值的重要指标。研究表明,乳酸菌添加剂可以改善青贮饲料的质量并提高消化率[38]。本研究中,各青贮饲料组IVDMD显著高于原料,同时LB组和LBPS组显著高于其他组。研究表明,添加乳酸菌可以提高青贮饲料IVDMD,这可能是在青贮发酵过程中,微生物分泌的酶降解了粗纤维[39]。Ferraretto等[40]研究发现,较低的pH可提高高湿玉米7 h瘤胃体外淀粉消化率。本研究使用的高湿玉米原料品种为高油958,该品种玉米的胚乳更加紧密,蛋白质与淀粉结合的更紧实,添加乳酸菌可以提高高湿玉米青贮饲料中乳酸和乙酸含量,并提高其中的淀粉颗粒分离度,从而促进瘤胃微生物更大程度地接触淀粉颗粒,进而提高消化率[41]。

4 结论

高湿玉米青贮饲料有着良好的发酵品质和营养价值,同时长链脂肪酸种类丰富,体外消化率较高。其中,发酵45 d后LBPS组高湿玉米青贮饲料发酵效果最好,添加布氏乳杆菌可以优化长链脂肪酸组成。综上所述,发酵45 d且添加布氏乳杆菌+山梨酸钾可以更好地提升高湿玉米青贮饲料发酵品质。

References

Publishing order | Descend order by publishing year | Descend order by cited within
[1]
于康震. 粮改饲是推进农业供给侧结构性改革的重要举措[J]. 农村工作通讯, 2017(9):5-8.

YU K Z. Grain-to-feed conversion is an important initiative to promote structural reform of agricultural supply side[J]. Newsletter About Work in Rural Areas, 2017(9):5-8. (in Chinese)

[2]
BURMEISTER H R, HARTMAN P A, SAUL R A. Microbiology of ensiled high-moisture corn[J]. Applied Microbiology, 1966, 14(1):31-34.

[3]
焦蓓蕾, 贺永强, 葛旭升, 等. 能量饲料高湿玉米饲用价值与效益分析[J]. 畜牧兽医科学(电子版), 2019(23):10-11.

JIAO B L, HE Y Q, GE X S, et al. Analysis of feeding value and benefit of high wet corn for energy feed[J]. Graziery Veterinary Sciences (Electronic Version), 2019(23):10-11. (in Chinese)

[4]
BUCHANAN-SMITH J, SMITH T K, MORRIS J R. High moisture grain and grain by-products[J]. Silage Science and Technology, 2003,42:825-854.

[5]
SZASZ J I, HUNT C W, SZASZ P A, et al. Influence of endosperm vitreousness and kernel moisture at harvest on site and extent of digestion of high-moisture corn by feedlot steers[J]. Journal of Animal Science, 2007, 85(9):2214-2221.

[6]
CANIZARES G L L, GONCALVES H C, COSTA C, et al. Use of high moisture corn silage replacing dry corn on intake,apparent digestibility,production and composition of milk of dairy goats[J]. Revista Brasileira de Zootecnia, 2011, 40(4):860-865.

[7]
马西青, 赵久然, 玉柱, 等. 我国高湿玉米青贮发展潜力分析[J]. 玉米科学, 2023, 31(2):54-58.

MA X Q, ZHAO J R, YU Z, et al. Development potential of high moisture corn silage in China[J]. Journal of Maize Sciences, 2023, 31(2):54-58. (in Chinese)

[8]
DE CARVALHO C C C R, CARAMUJO M J.The various roles of fatty acids[J]. Molecules, 2018, 23(10):2583.

[9]
王萍, 张银波, 江木兰. 多不饱和脂肪酸的研究进展[J]. 中国油脂, 2008, 33(12):42-46.

WANG P, ZHANG Y B, JIANG M L. Research advance in polyunsaturated fatty acid[J]. China Fats & Oils, 2008, 33(12):42-46. (in Chinese)

[10]
BERNES G, TURNER T, PICONOVA J. Sheep fed only silage or silage supplemented with concentrates:2.Effects on lamb performance and fatty acid profile of ewe milk and lamb meat[J]. Small Ruminant Research, 2012, 102(2/3):114-124.

[11]
ALVES S P, CABRITA A R J, JERÓNIMO E, et al. Effect of ensiling and silage additives on fatty acid composition of ryegrass and corn experimental silages[J]. Journal of Animal Science, 2011, 89(8):2537-2545.

[12]
LIU Q H, DONG Z H, SHAO T. Effect of additives on fatty acid profile of high moisture alfalfa silage during ensiling and after exposure to air[J]. Animal Feed Science and Technology, 2018,236:29-38.

[13]
韩立英, 周禾, 玉柱. 青贮饲料中脂肪酸研究进展[J]. 草地学报, 2012, 20(6):990-994.

HAN L Y, ZHOU H, YU Z. Research progress of fatty acid in silage[J]. Acta Agrestia Sinica, 2012, 20(6):990-994. (in Chinese)

[14]
王磊, 包锦泽, 田逢博, 等. 布氏乳杆菌对高湿玉米青贮饲料品质的影响[J]. 饲料工业, 2022, 43(2):35-39.

WANG L, BAO J Z, TIAN F B, et al. Effects of adding Lactobacillus buchneri on ensiling quality of high moisture corn[J]. Feed Industry, 2022, 43(2):35-39. (in Chinese)

[15]
许庆方, 玉柱, 韩建国, 等. 高效液相色谱法测定紫花苜蓿青贮中的有机酸[J]. 草原与草坪, 2007(2):63-65,67.

XU Q F, YU Z, HAN J G, et al. Determination of organic acids in alfalfa silage by high performance liquid chromatography[J]. Grassland and Turf, 2007(2):63-65,67. (in Chinese)

[16]
BRODERICK G A, KANG J H. Automated simultaneous determination of ammonia and total amino acids in ruminal fluid and in vitro media[J]. Journal of Dairy Science, 1980, 63(1):64-75.

[17]
LATIMER G W. Official methods of analysis of AOAC international[M]. 22nd ed. New York: AOAC Publications, 2023.

[18]
ISO.Animal feeding stuffs-determination of nitrogen content and calculation of crude protein content-part 1:Kjeldahl method:ISO 5983-1:2005[S]. Geneva: International Organization for Standardization, 2005.

[19]
VAN SOEST P J, ROBERTSON J B, LEWIS B A. Methods for dietary fiber,neutral detergent fiber,and nonstarch polysaccharides in relation to animal nutrition[J]. Journal of Dairy Science, 1991, 74(10):3583-3597.

[20]
王莹. 内蒙古荒漠草原主要植物养分含量、体外消化及产气特征研究[D]. 硕士学位论文. 呼和浩特: 内蒙古农业大学, 2019.

WANG Y. In study on nutrient content,in vitro digestion and gas production characteristics of main plants in Inner Mongolia desert steppe[D]. Master's Thesis. Hohhot: Inner Mongolia Agricultural University, 2019. (in Chinese)

[21]
QIU Q H, QIU X J, GAO C Y, et al. High-density diet improves growth performance and beef yield but affects negatively on serum metabolism and visceral morphology of Holstein steers[J]. Journal of Animal Physiology and Animal Nutrition, 2020, 104(5):1197-1208.

[22]
LARSON J, HOFFMAN P C. A method to quantify prolamin proteins in corn that are negatively related to starch digestibility in ruminants[J]. Journal of Dairy Science, 2008, 91(12):4834-4839.

[23]
SHAO T, ZHANG Z X, SHIMOJO M, et al. Comparison of fermentation characteristics of Italian ryegrass (Lolium multiflorum Lam.) and guineagrass (Panicum maximum Jacq.) during the early stage of ensiling[J]. Asian-Australasian Journal of Animal Sciences, 2005, 18(12):1727-1734.

[24]
JOBIM C C, NUSSIO L G, REIS R A, et al. Methodological advances in evaluation of preserved forage quality[J]. Revista Brasileira de Zootecnia, 2007,36:101-119.

[25]
CHERNEY J H, CHERNEY D J R. Assessing silage quality[J]. Silage Science and Technology, 2003,42:141-198.

[26]
邹璇, 王成, 陈晓阳, 等. 桉叶油和迷迭香油对柱花草青贮品质的影响[J]. 中国草地学报, 2022, 44(2):89-97.

ZOU X, WANG C, CHEN X Y, et al. Effects of eucalyptus oil and rosemary oil on silage quality of stylo[J]. Chinese Journal of Grassland, 2022, 44(2):89-97. (in Chinese)

[27]
OUDE ELFERINK S J, KROONEMAN J, GOTTSCHAL J C, et al. Anaerobic conversion of lactic acid to acetic acid and 1,2-propanediol by Lactobacillus buchneri[J]. Applied and Environmental Microbiology, 2001, 67(1):125-132.

[28]
WANG L, BAO J Z, ZHUO X L, et al. Effects of Lentilactobacillus buchneri and chemical additives on fermentation profile,chemical composition,and nutrient digestibility of high-moisture corn silage[J]. Frontiers in Veterinary Science, 2023,10:1296392.

[29]
SAYLOR B A, CASALE F, SULTANA H, et al. Effect of microbial inoculation and particle size on fermentation profile,aerobic stability,and ruminal in situ starch degradation of high-moisture corn ensiled for a short period[J]. Journal of Dairy Science, 2020, 103(1):379-395.

[30]
王燕. 芽孢杆菌对苜蓿青贮品质、干物质损失及微生物群落结构的调控研究[D]. 博士学位论文. 银川: 宁夏大学, 2023.

WANG Y.Mechanisms of Bacillus on the fermentation quality, dry matter loss,and microbial community of alfalfa silage[D].Ph.D. Thesis. Yinchuan: Ningxia University, 2023. (in Chinese)

[31]
BORREANI G, TABACCO E, SCHMIDT R J, et al. Silage review:factors affecting dry matter and quality losses in silages[J]. Journal of Dairy Science, 2018, 101(5):3952-3979.

[32]
FISHER A V, ENSER M, RICHARDSON R I, et al. Fatty acid composition and eating quality of lamb types derived from four diverse breed×production systems[J]. Meat Science, 2000, 55(2):141-147.

[33]
DEWHURST R J, SCOLLAN N D, LEE M R F, et al. Forage breeding and management to increase the beneficial fatty acid content of ruminant products[J]. Proceedings of the Nutrition Society, 2003, 62(2):329-336.

[34]
ELGERSMA A, ELLEN G, VAN DER HORST H, et al. Quick changes in milk fat composition from cows after transition from fresh grass to a silage diet[J]. Animal Feed Science and Technology, 2004, 117(1/2):13-27.

[35]
DOREAU M, CHILLIARD Y. Digestion and metabolism of dietary fat in farm animals[J]. British Journal of Nutrition, 1997, 78(Suppl.1):S15-S35.

[36]
柯文灿. 不同种类添加剂对紫花苜蓿青贮脂肪酸和蛋白质降解的影响[D]. 硕士学位论文. 兰州: 兰州大学, 2015.

KE W C. Studies on the characteristics of lipolysis and proteolysis in ensiled alfalfa (Medicago sativa L.) treated with different additives[D]. Master's Thesis. Lanzhou: Lanzhou University, 2015. (in Chinese)

[37]
KE W C, DING W R, XU D M, et al. Influences of addition of malic acid or citric acid,Lactobacillus plantarum and their mixtures on fermentation quality,proteolysis and fatty acid composition of ensiled alfalfa[J]. Archives of Animal Nutrition, 2018, 72(6):492-502.

[38]
ANDO S, ISHIDA M, OSHIO S, et al. Effects of isolated and commercial lactic acid bacteria on the silage quality,digestibility,voluntary intake and ruminal fluid characteristics[J]. Asian-Australasian Journal of Animal Sciences, 2006, 19(3):386-389.

[39]
XING L, CHEN L J, HAN L J. The effect of an inoculant and enzymes on fermentation and nutritive value of sorghum straw silages[J]. Bioresource Technology, 2009, 100(1):488-491.

[40]
FERRARETTO L F, TAYSOM K, TAYSOM D M, et al. Relationships between dry matter content,ensiling,ammonia-nitrogen,and ruminal in vitro starch digestibility in high-moisture corn samples[J]. Journal of Dairy Science, 2014, 97(5):3221-3227.

[41]
HOFFMAN P C, ESSER N M, SHAVER R D, et al. Influence of ensiling time and inoculation on alteration of the starch-protein matrix in high-moisture corn[J]. Journal of Dairy Science, 2011, 94(5):2465-2474.

Options
Outlines

/

〈 〉

京ICP备17050989号-2
Copyright © Chinese Journal of Animal Nutrition, All Rights Reserved.
Tel: 010－62817823　E-mail: cjan@vip.163.com
Powered by Beijing Magtech Co., Ltd.