1 材料与方法
1.1 试验材料
1.2 试验设计及饲养管理
表1 开食料营养水平(干物质基础)Table 1 Nutrient levels of the starter feed (DM basis) % |
| 项目Items | 含量Content |
|---|---|
| 粗蛋白质CP | 20.46 |
| 中性洗涤纤维NDF | 45.73 |
| 酸性洗涤纤维ADF | 11.48 |
| 粗脂肪EE | 3.85 |
| 粗灰分Ash | 2.03 |
| 钙Ca | 0.92 |
| 磷P | 0.52 |
表中各营养指标均为参照国标方法所得实测值。 | |
All nutrient indices presented in the table are measured values obtained following the corresponding methods of Chinese National Standards. |
1.3 样品采集
1.4 检测指标及方法
1.4.1 生长性能测定
1.4.2 瘤胃发酵参数测定
1.4.3 瘤胃菌群测定
1.5 数据处理与分析
2 结果与分析
2.1 琥珀酸、丁酸钠和异丁酸对哺乳犊牛生长性能的影响
表2 琥珀酸、丁酸钠和异丁酸对哺乳犊牛生长性能的影响Table 2 Effects of succinic acid, sodium butyrate and isobutyric acid on growth performance of suckling calves |
| 项目 Items | 组别Groups | 均值标准误 SEM | P值 P-value | |||
|---|---|---|---|---|---|---|
| CK | SA | SB | IB | |||
| 初始体重IBW/kg | 43.31 | 43.18 | 42.89 | 43.49 | 0.532 | 0.984 |
| 终末体重FBW/kg | 86.47 | 88.64 | 91.06 | 86.13 | 0.841 | 0.136 |
| 平均日增重ADG/(kg/d) | ||||||
| 第1~28天Days 1 to 28 | 0.63 | 0.57 | 0.69 | 0.63 | 0.015 | 0.053 |
| 第29~56天Days 29 to 56 | 0.91b | 1.05a | 1.03a | 0.90b | 0.022 | 0.016 |
| 第1~56天Days 1 to 56 | 0.77b | 0.81ab | 0.86a | 0.76b | 0.013 | 0.018 |
| 平均干物质采食量ADMI/(kg/d) | ||||||
| 第1~28天Days 1 to 28 | 0.85 | 0.83 | 0.89 | 0.86 | 0.010 | 0.120 |
| 第29~56天Days 29 to 56 | 1.41b | 1.50b | 1.60a | 1.45b | 0.020 | 0.002 |
| 第1~56天Days 1 to 56 | 1.13b | 1.17b | 1.25a | 1.16b | 0.013 | 0.006 |
| 料重比F/G | ||||||
| 第1~28天Days 1 to 28 | 1.36 | 1.46 | 1.32 | 1.39 | 0.028 | 0.341 |
| 第29~56天Days 29 to 56 | 1.55 | 1.44 | 1.59 | 1.63 | 0.033 | 0.204 |
| 第1~56天Days 1 to 56 | 1.47 | 1.44 | 1.46 | 1.53 | 0.021 | 0.529 |
同行数据肩标无字母或相同字母表示差异不显著(P>0.05),不同小写字母表示差异显著(P<0.05)。下表同。 | |
In the same row, values with no letter or the same letter superscripts mean no significant difference (P>0.05), while with different small letter superscripts mean significant difference (P<0.05). The same as below. |
2.2 琥珀酸、丁酸钠和异丁酸对哺乳犊牛瘤胃发酵参数的影响
表3 琥珀酸、丁酸钠和异丁酸对犊牛瘤胃液pH、氨态氮和微生物蛋白浓度的影响Table 3 Effects of succinic acid, sodium butyrate and isobutyric acid on pH, ammonia nitrogen and microbial protein concentrations in rumen fluid of suckling calves |
| 项目 Items | 组别Groups | 均值标准误 SEM | P值 P-value | |||
|---|---|---|---|---|---|---|
| CK | SA | SB | IB | |||
| pH | ||||||
| 第21天Day 21 | 7.11 | 7.01 | 7.13 | 6.99 | 0.023 | 0.083 |
| 第28天Day 28 | 6.88a | 6.65b | 6.68b | 6.90a | 0.041 | 0.001 |
| 第42天Day 42 | 6.94 | 6.75 | 6.73 | 6.83 | 0.037 | 0.105 |
| 第56天Day 56 | 6.75a | 6.45bc | 6.38c | 6.61ab | 0.037 | <0.001 |
| 氨态氮NH3-N/(mg/dL) | ||||||
| 第21天Day 21 | 9.54 | 11.62 | 10.27 | 11.50 | 0.432 | 0.298 |
| 第28天Day 28 | 13.05 | 19.59 | 15.40 | 15.79 | 1.078 | 0.174 |
| 第42天Day 42 | 12.06c | 22.07a | 18.70b | 15.51bc | 1.084 | <0.001 |
| 第56天Day 56 | 10.15 | 17.08 | 16.09 | 14.80 | 0.942 | 0.060 |
| 微生物蛋白MCP/(mg/mL) | ||||||
| 第21天Day 21 | 1.77a | 1.20b | 1.52ab | 1.69a | 0.067 | 0.006 |
| 第28天Day 28 | 1.04c | 1.40ab | 1.62a | 1.23bc | 0.063 | 0.004 |
| 第42天Day 42 | 1.00c | 1.93a | 1.75ab | 1.24bc | 0.106 | 0.003 |
| 第56天Day 56 | 1.22c | 1.85a | 1.67ab | 1.41bc | 0.074 | 0.007 |
表4 琥珀酸、丁酸钠和异丁酸对犊牛瘤胃液中挥发性脂肪酸浓度的影响Table 4 Effects of succinic acid, sodium butyrate and isobutyric acid on volatile fatty acid concentrations in rumen fluid of suckling calves mmol/mL |
| 项目 Items | 组别Groups | 均值标准误 SEM | P值 P-value | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CK | SA | SB | IB | ||||||||||
| 乙酸Acetic acid | |||||||||||||
| 第21天Day 21 | 11.98 | 12.52 | 11.22 | 9.81 | 0.544 | 0.282 | |||||||
| 第28天Day 28 | 10.55b | 13.66ab | 17.02a | 12.91ab | 0.827 | 0.037 | |||||||
| 第42天Day 42 | 11.47 | 14.77 | 16.33 | 14.51 | 0.812 | 0.131 | |||||||
| 第56天Day 56 | 19.54c | 21.94bc | 27.98a | 25.49ab | 1.083 | 0.011 | |||||||
| 丙酸Propionic acid | |||||||||||||
| 第21天Day 21 | 4.89 | 6.48 | 4.30 | 3.89 | 0.365 | 0.085 | |||||||
| 第28天Day 28 | 4.53 | 7.57 | 8.56 | 5.69 | 0.583 | 0.054 | |||||||
| 第42天Day 42 | 3.92b | 6.22b | 9.54a | 6.58b | 0.589 | 0.001 | |||||||
| 第56天Day 56 | 8.60b | 12.28ab | 16.46a | 14.46a | 0.852 | 0.002 | |||||||
| 丁酸Butyric acid | |||||||||||||
| 第21天Day 21 | 1.28ab | 1.61ab | 1.99a | 1.09b | 0.118 | 0.029 | |||||||
| 第28天Day 28 | 1.13b | 1.60ab | 2.24a | 1.18b | 0.136 | 0.007 | |||||||
| 第42天Day 42 | 0.93c | 1.30bc | 1.96a | 1.58ab | 0.108 | <0.001 | |||||||
| 第56天Day 56 | 1.41b | 2.53a | 3.05a | 2.92a | 0.167 | <0.001 | |||||||
| 异丁酸Isobutyric acid | |||||||||||||
| 第21天Day 21 | 0.68 | 0.58 | 0.60 | 0.55 | 0.022 | 0.210 | |||||||
| 第28天Day 28 | 0.59 | 0.69 | 0.52 | 0.74 | 0.041 | 0.240 | |||||||
| 第42天Day 42 | 0.62 | 0.87 | 0.74 | 0.63 | 0.047 | 0.216 | |||||||
| 第56天Day 56 | 1.02 | 1.12 | 1.08 | 0.81 | 0.080 | 0.547 | |||||||
| 总挥发性脂肪酸Total VFAs | |||||||||||||
| 第21天Day 21 | 19.92 | 22.44 | 19.16 | 16.37 | 0.973 | 0.157 | |||||||
| 第28天Day 28 | 17.63b | 25.16ab | 30.14a | 22.08ab | 1.609 | 0.035 | |||||||
| 第42天Day 42 | 19.79b | 24.50ab | 30.10a | 24.47ab | 1.461 | 0.008 | |||||||
| 第56天Day 56 | 32.01b | 45.37a | 54.13a | 44.11a | 2.390 | 0.005 | |||||||
2.3 琥珀酸、丁酸钠和异丁酸对哺乳犊牛瘤胃菌群结构的影响
2.3.1 瘤胃菌群操作分类单元(OTUs)数量
图1 基于OTUs水平的瘤胃菌群Venn图A:第28天瘤胃菌群Venn图;B:第56天瘤胃菌群Venn图。 CK-L-28、SA-L-28、SB-L-28、IB-L-28分别表示CK、SA、SB、IB组第28天的样品,CK-L-56、SA-L-56、SB-L-56、IB-L-56分别表示CK、SA、SB、IB组第56天的样品。下图同。 Fig.1 Venn diagram of rumen microbiota based on OTUs level A: Venn diagram of rumen microbiota at day 28; B: Venn diagram of rumen microbiota at day 56. CK-L-28, SA-L-28, SB-L-28 and IB-L-28 represented the samples collected on day 28 from the CK, SA, SB and IB groups, respectively. CK-L-56, SA-L-56, SB-L-56 and IB-L-56 represent the samples collected on day 56 from the CK, SA, SB and IB groups, respectively. The same as below. |
2.3.2 瘤胃菌群Alpha多样性分析
表5 琥珀酸、丁酸钠和异丁酸对哺乳犊牛瘤胃菌群Alpha多样性的影响Table 5 Effects of succinic acid, sodium butyrate and isobutyric acid on Alpha diversity of rumen microbiota of suckling calves |
| 项目 Items | 组别Groups | 均值标准误 SEM | P值 P-value | |||
|---|---|---|---|---|---|---|
| CK | SA | SB | IB | |||
| 第28天Day 28 | ||||||
| ACE指数ACE index | 1 012.77 | 1 053.72 | 1 069.82 | 1 054.47 | 11.139 | 0.315 |
| Chao指数Chao index | 989.56 | 1 023.98 | 1 029.32 | 1 014.28 | 10.597 | 0.574 |
| Shannon指数Shannon index | 4.94 | 5.26 | 4.74 | 5.40 | 0.095 | 0.050 |
| Simpson指数Simpson index | 0.90 | 0.92 | 0.86 | 0.94 | 0.011 | 0.053 |
| 第56天Day 56 | ||||||
| ACE指数ACE index | 1 172.32a | 1 203.72a | 1 088.38b | 1 022.00b | 16.984 | <0.001 |
| Chao指数Chao index | 1 127.17ab | 1 150.48a | 1 059.47bc | 1 001.61c | 14.989 | <0.001 |
| Shannon指数Shannon index | 5.57a | 5.57a | 5.19ab | 5.04b | 0.082 | 0.038 |
| Simpson指数Simpson index | 0.94 | 0.93 | 0.92 | 0.91 | 0.005 | 0.390 |
2.3.3 瘤胃菌群Beta多样性分析
2.3.4 瘤胃菌群组成分析
图3 瘤胃菌群组成A:第28天瘤胃菌群门水平组成;B:第56天瘤胃菌群门水平组成;C:第28天瘤胃菌群属水平组成;D:第56天瘤胃菌群属水平组成。 Fig.3 Composition of rumen microbiota A: composition of rumen microbiota at phylum level at day 28; B: composition of rumen microbiota at phylum level at day 56; C: composition of rumen microbiota at genus level at day 28; D: composition of rumen microbiota at genus level at day 56. |
2.3.5 瘤胃菌群优势菌门差异分析
表6 琥珀酸、丁酸钠和异丁酸对第28天犊牛瘤胃优势菌门(前10位)相对丰度的影响Table 6 Effects of succinic acid, sodium butyrate and isobutyric acid on relative abundance of dominant bacterial phyla (top 10) in rumen of calves at day 28 |
| 项目 Items | 组别Groups | 均值标准误 SEM | P值 P-value | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CK | SA | SB | IB | ||||||||||
| 拟杆菌门Bacteroidota | 46.35ab | 47.73ab | 52.80a | 35.51b | 2.251 | 0.042 | |||||||
| 芽孢杆菌门Bacillota | 34.08 | 27.70 | 25.28 | 36.12 | 2.019 | 0.183 | |||||||
| 假单胞菌门Pseudomonadota | 8.09b | 14.63ab | 10.04b | 21.71a | 1.638 | 0.011 | |||||||
| 放线菌门Actinomycetota | 7.30 | 2.65 | 6.29 | 2.41 | 1.392 | 0.506 | |||||||
| 嗜热脱硫细菌门Thermodesulfobacteriota | 0.62b | 2.14a | 1.36ab | 1.27b | 0.158 | 0.005 | |||||||
| 螺旋体门Spirochaetota | 0.37b | 2.76a | 1.39ab | 0.71b | 0.316 | 0.031 | |||||||
| 甲烷杆菌门Methanobacteriota | 0.74 | 0.80 | 1.52 | 0.90 | 0.159 | 0.286 | |||||||
| 互养菌门Synergistota | 1.92 | 0.23 | 0.35 | 0.96 | 0.295 | 0.158 | |||||||
| 蓝细菌门Cyanobacteriota | 0.16 | 0.50 | 0.65 | 0.20 | 0.123 | 0.437 | |||||||
| 迷踪菌门Elusimicrobiota | 0.08 | 0.29 | 0.12 | 0.05 | 0.047 | 0.265 | |||||||
表7 琥珀酸、丁酸钠和异丁酸对第56天犊牛瘤胃优势菌门(前10位)相对丰度的影响Table 7 Effects of succinic acid, sodium butyrate and isobutyric acid on relative abundance of dominant bacterial phyla (top 10) in rumen of calves at day 56 |
| 项目 Items | 组别Groups | 均值标准误 SEM | P值 P-value | |||
|---|---|---|---|---|---|---|
| CK | SA | SB | IB | |||
| 拟杆菌门Bacteroidota | 45.00a | 48.85a | 48.57a | 33.87b | 1.989 | 0.018 |
| 芽孢杆菌门Bacillota | 39.39 | 31.23 | 36.40 | 40.50 | 1.724 | 0.231 |
| 假单胞菌门Pseudomonadota | 7.26b | 7.13b | 3.94b | 15.38a | 1.170 | 0.002 |
| 螺旋体门Spirochaetota | 2.28 | 5.27 | 1.77 | 1.72 | 0.669 | 0.188 |
| 放线菌门Actinomycetota | 0.93 | 1.66 | 2.32 | 3.74 | 0.545 | 0.316 |
| 髌骨菌门Patescibacteria | 0.69 | 1.95 | 3.54 | 1.52 | 0.725 | 0.579 |
| 甲烷杆菌门Methanobacteriota | 1.50a | 0.56b | 1.07ab | 1.56a | 0.133 | 0.021 |
| 嗜热脱硫细菌门Thermodesulfobacteriota | 1.10 | 1.20 | 1.24 | 1.02 | 0.162 | 0.965 |
| 互养菌门Synergistota | 0.59 | 1.09 | 0.31 | 0.36 | 0.201 | 0.519 |
| 蓝细菌门Cyanobacteriota | 0.46 | 0.26 | 0.72 | 0.17 | 0.126 | 0.434 |
