Chinese Journal of Animal Nutrition >

2025 , Vol. 37 >Issue 3: 2032 - 2044

DOI: https://doi.org/10.12418/CJAN2025.172

RESEARCH PAPER

Evaluation of Nutritional Values of Leymus chinensis under Different Fertilization Treatments Using Cornell Net Carbohydrate and Protein System and NRC Model

  • CAI Yuan ,
  • LI Ziyong ,
  • ZHANG Chunyan ,
  • WU Haiying ,
  • ZHOU Hongxin ,
  • LI Xizheng ,
  • CHENG Wenge , *
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  • Jilin Biological Research Institute, Changchun 130012, China
*professor, E-mail:

Received date: 2024-07-26

  Online published: 2025-03-13

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Abstract

The purpose of this study was to evaluate the nutritional values of Leymus chinensis under different fertilization treatments by using Cornell net carbohydrate and protein system (CNCPS) and NRC model. The “3414” optimal regression scheme was used to conduct the fertilization experiment, including 3 factors as nitrogen, phosphorus, potassium, 4 levels, 14 treatments, and no fertilization as the control. A total of 42 experimental plots were randomized block designed with 3 replicates in each treatment. The experimental material was Jisheng No.1 Leymus chinensis. After the experiment, the nutrient contents in Leymus chinensis were determined, CNCPS components were analyzed, and digestible nutrient contents and energy values were estimated by NRC model. The results showed as follows: 1) the crude protein (CP) content in Leymus chinensis was closely related to the nitrogen fertilizer applied amount, among which high nitrogen fertilizer treatment (N3P2K2 treatment) had the highest CP content, but there was no significant difference between it and N2P2K0 treatment (P>0.05); the ether extract (EE) content was also closely related to the nitrogen fertilizer applied amount, but excessive nitrogen fertilizer would reduce the EE content; the soluble crude protein (SCP) content in 13 fertilization treatments was significantly higher than that in the control (P<0.05), and the SCP content in N2P2K0 treatment was the highest with 5.31%; meanwhile, the non-protein nitrogen (NPN) content in 13 fertilization treatments was significantly higher than that in the control (P<0.05). 2) The non-protein nitrogen (PA) content in protein components of CNCPS in Leymus chinensis in all treatments was 23.63% to 34.06%, and the PA content in 4 fertilization treatments was significantly higher than that in the control (P<0.05); after fertilization, the proportions of fast degrading true protein (PB1) and medium degrading true protein (PB2) in CP were increased, and the non-degradable nitrogen (PC) content was positively correlated with the PA content. In the carbohydrate components of CNCPS, the medium degrading carbohydrate (CB1) content in Leymus chinensis treated with high nitrogen fertilizer (N3P2K2), medium phosphate fertilizer (N2P2K2) and high potassium fertilizer (N2P2K3) was significantly higher than that in control (P<0.05); there were significant differences in contents of fast degrading carbohydrate (CA) and slow degrading carbohydrate (CB2) in N2P0K2 treatment, N2P1K2 treatment and N2P2K2 treatment compared with control group (P<0.05), in which CA content was increased due to fertilization, while CB2 content was decreased due to fertilization; after fertilization, the unavailable carbohydrate (CC) content was increased. 3) After fertilization, the remen true digestible non-fiber carbohydrate (tdNFC) content in Leymus chinensis was increased; the true digestible crude protein (tdCP) content in all fertilization treatments was significantly higher than that in control (P<0.05), and N3P2K2 treatment was the highest; the true digestible neutral detergent fiber (tdNDF) content in N2P0K2 treatment, N2P1K2 treatment and N2P2K2 treatment was significantly lower than that in control (P<0.05); the true digestible fatty acid (tdFA) content in all fertilization treatments except N3P2K2 treatment was significantly higher than that in control (P<0.05); the change trend of digestible nutrient content and energy values of Leymus chinensis under different fertilization treatments was basically the same, and N2P2K0 treatment had the best effect. In summary, the application of nitrogen fertilizer can significantly increase the CP content in Leymus chinensis, but there is NPN in it, and the application of potassium fertilizer should be careful. Judging from the nutritional value of Leymus chinensis comprehensively, the fertilization effect of N2P2K0 treatment was better in this experiment.

Key words： Leymus chinensis; CNCPS; NRC; “3414” fertilization effect; nutritional values

Cite this article

CAI Yuan , LI Ziyong , ZHANG Chunyan , WU Haiying , ZHOU Hongxin , LI Xizheng , CHENG Wenge . Evaluation of Nutritional Values of Leymus chinensis under Different Fertilization Treatments Using Cornell Net Carbohydrate and Protein System and NRC Model[J]. Chinese Journal of Animal Nutrition, 2025 , 37(3) : 2032 -2044 . DOI: 10.12418/CJAN2025.172

羊草(Leymus chinensis)又名碱草,是典型草原建群种之一,为禾本科C3光合型植物。羊草适口性好、无性繁殖力很强,这使其成为温带草甸草原的优势种,同时也是欧亚大陆草原区东部草甸草原及典型草原的建群种,在生态环境保护方面具有举足轻重的地位[1]。此外,羊草生态适应性广、抗逆性强,可在寒冷干燥的条件下良好生长[2-3],一次播种成功可以利用几十年,可用于修复和治理退化、沙化及盐渍化草地,有利于建设现代化生态健康牧场,加速我国草牧业高质量发展及生态文明建设[4]。
“3414”(指氮、磷、钾3个因素,4个水平,14个处理)施肥试验设计是在国外“3411”多点施肥试验方案的基础上,加了12~14等3个处理后得到的试验方案,该方案既吸收了回归最优设计处理少、效率高的优点,又符合肥料试验和施肥决策的专业要求。“3414”试验方案最初多应用于小麦、水稻和玉米等一年生大田作物。近年来,“3414”试验方案在多年生作物香梨、桂花和桔梗上的应用研究也越来越多,但在羊草上的应用研究却未见报道。
康奈尔净碳水化合物-蛋白质体系(Cornell net carbohydrate and protein system,CNCPS)由美国康奈尔大学提出、建立和完善,该体系作为一种国际公认的饲料营养价值评价体系,是在Van Soest体系的基础上,将饲料(包括牧草、牧草加工产品和粮食加工副产物等)的化学成分分析和植物细胞成分与反刍动物的消化有机结合起来,为准确评估羊草的营养价值提供了有力工具[5⇓-7]。经过不断的优化更新以及数据扩增,现在CNCPS软件已更新到6.5.5版,其模型在预测的准确性和效率以及功能上均大大提高[8⇓⇓-11]。Martineau等[12-13]应用CNCPS和NRC模型评价了3种奶牛饲料在奶牛体内的氨基酸与氮化合物流出的能力;Dong等[14]研究了饲料中氨态氮(NH3-N)含量与CNCPS氮组分的关系,并进一步比较了用于估算瘤胃发酵NH3-N含量的多元线性回归(multiple linear regression,MLR)和人工神经网络(artificial neural network,ANN)模型的性能;Thers等[15]研究了2种禾本科牧草在增氮施肥制度下的生长情况,并比较了3种豆科牧草在遵循多次刈割的情况下,使用CNCPS来估计潜在的可提取蛋白质,结果表明,整个生长季节均需要注意田间管理的优化,而不仅仅是只注重第1次收割,因为粗蛋白质(crude protein,CP)产量和质量在5种牧草的不同收割时期中都达到峰值。此外,CNCPS在创建的初始就不断融入新的考量因素,通过不断的发展与应用,现在已经形成多学科交叉性研究,并已经在生产实践起到了重要作用[16]。
随着现代畜牧业的发展,利用CNCPS对牧草营养价值的评估变得日益重要,但目前对牧草营养价值的评估大多数还只是针对不同种类牧草、不同类型饲料、不同粮食加工副产物以及不同加工方法等方面的研究[17⇓⇓⇓⇓⇓-23],在同类牧草在经过不同施肥处理后,牧草营养价值评估方面的研究却很少。因此,为了深入研究氮、磷、钾等不同营养元素对羊草营养价值的影响,本研究采用“3414”试验方案设计了14种不同的施肥处理,并运用CNCPS和NRC(2001)模型对不同施肥处理下羊草的营养价值进行更系统与精准的评价。

1 材料与方法

1.1 试验区自然条件情况

试验地点在吉林省生物研究所乾安县安字镇渭字村试验基地,该地区地处东经124°02'、北纬45°01',年平均气温在4.4~4.8 ℃,年日照时间为2 867.6 h,年无霜期平均天数为145.3 d,年平均降水量为421.4 mm。

1.2 试验材料

供试材料为吉林省生物研究所自主培育的吉生1号羊草,供试肥料为尿素(氮含量为46%)、磷酸二氢钙(五氧化二磷含量为60%)和硫酸钾(氧化钾含量为52%)。

1.3 试验设计

本试验采用“3414”试验方案,其是二次回归模型D-最优设计的一种,指3个因素(氮、磷、钾)、4个水平、14个处理的随机区组设计,其中,水平0为不施肥(对照),水平2为当地最佳施肥量的近似值,且水平1=水平2×0.5,水平3=水平2×1.5,共14个处理。
本试验每个施肥小区长50 m、宽10 m,小区面积500 m2,小区间距2 m,每个处理3个重复,共计42个小区。所有肥料分2次施入,分别是在4月末和6月上旬,施肥量见表1。
表1 “3414”试验设计和施肥方案

Table 1 “3414” test design and fertilization schedule

编号
Number		 处理
Treatments		 氮
N(X1)		 五氧化二磷
P2O5(X2)		 氧化钾
K2O (X3)		 施肥量Fertilizing amount/(kg/hm2)
氮
N		 五氧化二磷
P2O5		 氧化钾
K2O
1 N0P0K0 0 0 0 0 0 0
2 N0P2K2 0 2 2 0 100 80
3 N1P2K2 1 2 2 60 100 80
4 N2P0K2 2 0 2 120 0 80
5 N2P1K2 2 1 2 120 50 80
6 N2P2K2 2 2 2 120 100 80
7 N2P3K2 2 3 2 120 150 80
8 N2P2K0 2 2 0 120 100 0
9 N2P2K1 2 2 1 120 100 40
10 N2P2K3 2 2 3 120 100 120
11 N3P2K2 3 2 2 180 100 80
12 N1P1K2 1 1 2 60 50 80
13 N1P2K1 1 2 1 60 100 40
14 N2P1K1 2 1 1 120 50 40

1.4 试验方法

1.4.1 营养成分测定

干物质(dry matter,DM)、CP、粗灰分(crude ash,Ash)、粗脂肪(ether extract,EE)等常规营养成分含量分别参照《饲料中水分的测定》(GB/T 6435—2014)、《饲料中粗蛋白的测定 凯氏定氮法》(GB/T 6432—2018)、《饲料中粗灰分的测定》(GB/T 6438—2007)、《饲料中粗脂肪的测定》(GB/T 6433—2006)的方法进行测定;淀粉(Starch)含量参照《饲料中淀粉总含量的测定 酶法》(GB/T 42491—2023)的方法进行测定;中性洗涤纤维(neutral detergent fiber,NDF)、酸性洗涤纤维(acid detergent fiber,ADF)、酸性洗涤木质素(acid detergent lignin,ADL)、中性洗涤不溶粗蛋白质(neutral detergent insoluble crude protein,NDICP)和酸性洗涤不溶粗蛋白质(acid detergent insoluble crude protein,ADICP)含量参照Van Soest等[24]的方法进行测定;可溶性粗蛋白质(soluble crude protein,SCP)和非蛋白氮(NPN)含量根据CNCPS的方法进行测定,每种样本测定3个重复。

1.4.2 CNCPS组分分析

在CNCPS蛋白质组分中,将蛋白质分为3个组分,分别为非蛋白氮(PA,即NPN)、真蛋白质(PB)和不可降解氮(PC),其中PB又可分为快速降解真蛋白质(PB1)、中速降解真蛋白质(PB2)和慢速降解真蛋白质(PB3)。在CNCPS碳水化合物(CHO)组分中,CHO则分为4个组分,分别为快速降解碳水化合物(CA)、中速降解碳水化合物(CB1)、慢速降解碳水化合物(CB2)和不可利用碳水化合物(CC);其中,CA为糖类,CB1为淀粉和果胶,CB2为可利用纤维,CC为不可利用纤维(是ADL的2.4倍),且CA和CB1为非结构性碳水化合物(non-structural carbohydrate,NSC)。
CNCPS组分含量计算公式如下:
CHO(% DM)=100-CP(% DM)-EE(% DM)-Ash(%DM);
CC(% CHO)=100×NDF(% DM)×0.01×ADL(% NDF)×2.4/CHO(% DM);
CB2(% CHO)=100×[NDF(% DM)-NDICP(% CP)×0.01×CP(% DM)-NDF(% DM)×0.01×ADL(% NDF)×2.4]/CHO(% DM);
NSC(% CHO)=100-CB2(% CHO)-CC(% CHO);
CA(% CHO)=[100-Starch(% NSC)]×[100-CB2(% CHO)-CC(% CHO)]/100;
CB1(% CHO)=Starch(% NSC)×[100-CB2(% CHO)-CC(%CHO)]/100;
PA(% CP)=NPN(% SCP)×0.01×SCP(% CP);
PB1(% CP)=SCP(% CP)-PA(% CP);
PC(% CP)=ADICP(% CP);
PB3(% CP)=NDICP(% CP)-ADICP(% CP);
PB2(% CP)=100-PA(% CP)-PB1(% CP)-PB3(% CP)-PC(% CP)。

1.4.3 NRC模型分析

采用NRC(2001)模型估测不同施肥处理下羊草在奶牛瘤胃真可消化非纤维碳水化合物(tdNFC)、真可消化粗蛋白质(tdCP)、真可消化中性洗涤纤维(tdNDF)和真可消化脂肪酸(tdFA)含量,并通过上述指标估测各个施肥处理下羊草的维持水平总可消化养分(TDNm)、生产水平消化能(DEp)、生产水平代谢能(MEp)和生产水平泌乳净能(NElp),同时应用肉牛估测模型预测各种饲料的维持净能(NEm)和增重净能(NEg)。预测公式如下[25]:
tdNFC(g/kg DM)=0.98×{1-[(NDF-NDICP)+CP+EE+Ash]}×PAF。
tdCP(g/kg DM)=CP×EXP[-1.2×(ADICP/CP)];
tdFA(g/kg DM)=FA=EE-1;
tdNDF(g/kg DM)=0.75×(NDF-NDICP-ADL)×{1-[ADL/(NDF-NDICP)]0.667}。
式中:PAF为加工校正因子,一般取值为1;FA为脂肪酸,如果EE<1,则FA=0。
TDNm(%)=tdNFC+tdCP+(tdFA×2.25)+tdNDF-7;
DE1X=(tdNFC/100)×4.2+(tdNDF/100)×4.2+(tdCP/100)×5.6+(FA/100)×9.4-0.3;
折扣系数=[TDNm-(0.18×TDNm-10.3)]×2/TDNm;
DEp(MJ/kg)=DE1X×折扣系数;
MEp(MJ/kg)=1.01×DEp-0.45;
NElp(MJ/kg)=0.703×MEp-0.19;
NEm(MJ/kg)=1.37×(DE1X×0.82)-0.138×(DE1X×0.82)2+0.010 5×(DE1X×0.82)3-1.12;
NEg(MJ/kg)=1.42×(DE1X×0.82)-0.174×(DE1X×0.82)2+0.012 2×(DE1X×0.82)3-1.65。
式中:DE1X为1倍维持水平的消化能;如果TDNm<60%,消化率的折扣忽略不计,即折扣系数=1。

1.5 数据处理与分析

所有数据均采用Excel 2013软件进行基本处理,然后采用SPSS 26.0软件进行单因素方差分析,并采用Duncan氏法进行组间多重比较,结果数据用“平均值±标准差”形式表示,以P<0.05为差异显著。

2 结果与分析

2.1 不同施肥处理羊草基础营养成分分析

由表2可知,羊草CP含量与氮肥的施入量密切相关,在高氮肥处理(N3P2K2处理)中,CP含量最高,显著高于除N2P2K0处理外的其他处理(P<0.05),这说明该处理的氮元素施用量可能尚未达到最大值,羊草CP含量依然有挖掘的潜力;同时,中氮肥处理的羊草CP含量高于低氮肥和无氮肥处理,从经济性来看N2P2K0处理羊草CP含量与N3P2K2处理无显著差异(P>0.05),因此N2P2K0处理的施用量较佳。羊草EE含量也与氮肥的施入量密切相关,但是过量的氮肥反而会影响羊草EE含量,使EE含量降低。从羊草Ash含量变化的结果来看,N2P1K2处理羊草Ash含量最高为5.40%。羊草Starch含量在高氮肥处理(N3P2K2处理)中最高,但各处理间均无显著差异(P>0.05)。羊草ADF含量在所有施肥处理中均显著低于对照(P<0.05),含量平均值比对照降低5.00个百分点;其中,N2P2K0处理ADF含量降低最多,比对照降低7.17个百分点。在羊草NDF含量的变化中,N2P2K2处理NDF含量最低为48.44%,比对照降低11.54个百分点。羊草ADICP含量在所有施肥处理中只有N0P2K2处理和N2P2K2处理略低于对照,其余处理均高于对照;羊草NDICP含量的变化几乎与ADICP含量变化相反,所有施肥处理的NDICP含量变化都低于对照,其中有11个处理显著低于对照(P<0.05)。羊草SCP含量在13个施肥处理中均显著高于对照(P<0.05),其中N2P2K0处理最高,SCP含量达到5.31%。13个施肥处理的羊草NPN含量均显著高于对照(P<0.05),其中N1P1K2处理最高,NPN含量达到2.89%。
表2 不同施肥处理对羊草营养成分含量的影响

Table 2 Effects of different fertilization treatments on nutrient contents of Leymus chinensis

项目
Items		 干物质
DM/%		 粗蛋白质
CP/% DM		 粗脂肪
EE/% DM		 粗灰分
Ash/% DM		 淀粉
Starch/
% DM		 酸性洗
涤纤维
ADF/%
DM		 中性洗
涤纤维
NDF/%
DM		 酸性洗涤
木质素
ADL/%
DM		 酸性洗
涤不溶
粗蛋白质
ADICP/%
DM		 中性洗涤
不溶粗
蛋白质
NDICP/
% DM		 可溶性
粗蛋白质
SCP/%
DM		 非蛋白氮
NPN/%
DM
处理Treatments
N0P0K0 88.41±1.57 6.62±0.26a 2.07±0.15a 4.41±0.64ab 3.32±0.21 45.85±1.02e 59.98±1.59cd 6.90±0.30cdef 1.74±0.14ab 5.52±0.15e 1.87±0.25a 1.67±0.30a
N0P2K2 88.83±0.52 7.49±0.20b 2.55±0.10cd 4.83±0.15bcd 4.08±0.11 42.81±0.57d 57.63±1.09bcd 7.14±0.24ef 1.70±0.13a 4.45±0.16d 2.86±0.10bc 2.24±0.41bcd
N1P2K2 88.56±0.53 8.96±0.90d 2.65±0.09d 5.16±0.25d 4.17±0.17 40.05±0.87abc 54.02±1.49abc 6.81±0.10bcde 2.07±0.13bc 4.23±0.14cd 3.87±0.29g 2.53±0.12def
N2P0K2 90.50±0.95 8.45±0.13cd 2.31±0.06b 5.03±0.23cd 4.09±0.14 41.23±1.00bcd 49.09±1.33a 6.7±0.14abcd 2.47±0.12de 5.17±0.18e 3.83±0.12g 2.40±0.13cde
N2P1K2 90.66±0.86 8.89±0.04cd 2.43±0.05bc 5.40±0.08d 4.19±0.15 40.96±0.58bcd 48.84±5.76a 6.57±0.25abc 2.39±0.18cd 3.05±0.23a 3.34±0.13def 2.76±0.08fg
N2P2K2 88.96±1.72 8.47±0.27cd 2.29±0.03b 5.39±0.25d 4.38±0.09 40.99±0.79bcd 48.44±8.95a 6.94±0.08def 1.54±0.29a 3.58±0.17b 3.52±0.28fg 2.29±0.15bcd
N2P3K2 89.50±1.57 8.42±0.66cd 2.37±0.03b 5.26±0.28d 3.86±0.41 40.51±0.55abc 56.38±1.28bcd 6.39±0.06a 1.76±0.16ab 3.88±0.22b 3.00±0.12bcd 2.14±0.08bc
N2P2K0 88.71±0.57 10.94±0.12e 2.65±0.07d 4.07±0.27a 4.01±0.22 38.68±0.36a 62.56±2.92d 6.64±0.15abcd 2.46±0.16de 3.68±0.21b 5.31±0.35h 2.60±0.07efg
N2P2K1 89.76±0.98 8.83±0.05cd 2.66±0.07d 5.18±0.15d 3.80±0.09 39.92±0.23abc 57.29±1.41bcd 6.54±0.20ab 2.77±0.20e 4.33±0.20d 3.42±0.16ef 2.09±0.11b
N2P2K3 90.23±0.23 8.38±0.35cd 2.85±0.07e 4.09±0.40a 4.31±0.16 41.59±0.53cd 62.53±2.38d 6.62±0.22abcd 2.52±0.22de 4.87±0.28e 2.67±0.19b 2.53±0.09def
N3P2K2 89.17±0.05 11.12±0.15e 2.12±0.12a 5.35±0.22d 4.74±0.08 41.77±1.49cd 57.11±1.45bcd 6.52±0.12ab 2.53±0.28de 4.19±0.33cd 5.10±0.18h 2.54±0.08def
N1P1K2 90.57±0.30 8.52±0.35cd 3.37±0.12f 5.14±0.07d 3.18±1.93 39.48±2.50ab 51.87±1.76ab 7.05±0.07ef 2.26±0.16cd 3.69±0.16b 3.12±0.15cde 2.89±0.12g
N1P2K1 89.63±1.76 8.23±0.31c 2.63±0.07d 4.50±0.47abc 4.26±0.19 41.81±0.90cd 56.25±1.22bcd 6.69±0.12abcd 2.46±0.23de 3.54±0.16b 2.86±0.11bc 2.56±0.11ef
N2P1K1 89.97±0.46 8.69±0.15cd 2.86±0.11e 4.57±0.11abc 4.36±0.11 41.23±0.93bcd 62.10±2.55d 7.24±0.27f 2.20±0.11cd 3.16±0.15a 3.64±0.18fg 2.59±0.09ef
P值
P-value		 0.112 2 <0.000 1 <0.000 1 <0.000 1 0.111 3 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1

同列数据肩标不同字母表示差异显著(P<0.05),相同字母或无字母表示差异不显著(P>0.05)。下表同。

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

如图1所示,施肥前,羊草DM含量与CP和Starch含量呈较强正相关,而与EE和SCP含量呈较强负相关;CP含量与EE和ADL含量呈较强负相关;EE含量与ADF和SCP含量呈较强正相关。不过,施肥后,羊草营养成分含量之间的相关性较施肥前有所减弱。
图1 施肥前(左)和施肥后(右)羊草基础营养成分的相关性热图

*表示显著相关(P<0.05),**(P<0.01)和***(P<0.001)表示极显著相关。

Fig.1 Correlation heat maps of basic nutrients in Leymus chinensis before (left) and after (right) fertilization

* indicated significant correlation (P<0.05), and ** (P<0.01) and *** (P<0.001) indicated extremely significant correlation.

2.2 不同施肥处理羊草CNCPS组分分析

由表3可知,各施肥处理羊草CHO含量均显著低于对照(P<0.05),其中高氮肥处理(N3P2K2处理)降低最多,降低了5.48个百分点。各处理羊草PA含量变化在23.63%~34.06%,其中有4个施肥处理PA含量显著高于对照(P<0.05)。在羊草PB中,施肥后PB1和PB2所占比例绝大多数都有所提高,其中PB1含量在N2P2K0处理和N3P2K2处理较高,均超过了20%;PB2含量在N2P1K2处理较高,达到28.10%;施肥后PB3所占比例却都有所下降,平均值下降22.64个百分点。各处理羊草PC含量在18.07%~31.32%,从PA和PC含量对比来看,PA与PC呈现出相对的正相关(多数处理符合这一规律,只有小部分数据不太明显),这也说明施肥后增加的PA中有些是无法被彻底消化吸收的。各处理羊草CB1含量变化不明显,只有3个施肥处理CB1含量显著高于对照(P<0.05),其他处理则无显著差异(P>0.05),而有显著差异的3个处理分别是高氮肥(N3P2K2)、中磷肥(N2P2K2)和高钾肥(N2P2K3)处理,这说明超量的氮、磷、钾都会使羊草中的CB1含量提高;CA含量与CB2含量的变化正好相反,但都是N2P0K2、N2P1K2和N2P2K2这3个处理与对照有显著差异(P<0.05),其中CA含量因为施肥而提高,而CB2含量则因为施肥而降低,2个指标间呈相对的负相关;从CC含量的变化来看,施肥后CC含量都有所提高,这说明增加的纤维或纤维素中,不可利用纤维占有一定的比重。
表3 不同施肥处理羊草CNCPS组分分析

Table 3 Analysis of CNCPS components of Leymus chinensis under different fertilization treatments

项目
Items		 非蛋白氮
PA/%
CP		 快速降解
真蛋白质
PB1/%
CP		 中速降解
真蛋白质
PB2/%
CP		 慢速降解
真蛋白质
PB3/% CP		 不可降解氮
PC/%
CP		 碳水化合物
CHO/%
DM		 非结构性
碳水化合物
NSC/%
CHO		 快速降解
碳水化合物
CA/%
CHO		 中速降解
碳水化合物
CB1/%
CHO		 慢速降解
碳水化合物
CB2/%
CHO		 不可利用
碳水化合物
CC/%
CHO
处理Treatments
N0P0K0 25.29±4.77abc 2.17±0.70ab 3.42±0.85a 42.07±2.86g 26.25±2.12cd 86.90±0.55g 12.17±1.41a 8.34±2.38ab 3.82±0.26a 68.76±1.71c 19.07±0.88abc
N0P2K2 29.98±6.10cdef 5.36±3.81ab 5.13±3.54a 36.74±4.58g 22.67±1.40abc 85.13±0.25f 12.42±0.99a 7.62±1.79ab 4.80±0.14ab 67.44±1.33c 20.14±0.63def
N1P2K2 28.37±1.58bcde 15.20±5.65ef 8.95±1.51ab 24.20±2.60ef 23.29±3.38bc 83.23±1.05cd 15.67±1.67abc 10.66±2.76abcd 5.01±0.14ab 64.68±2.53abc 19.65±0.49bcde
N2P0K2 28.45±1.99bcde 16.94±1.68f 3.55±1.32a 21.88±1.58de 29.19±1.65de 84.21±0.05e 22.86±0.67c 18.00±1.18d 4.86±0.17ab 58.04±1.57a 19.10±0.41abc
N2P1K2 31.09±0.93ef 6.52±0.48bc 28.10±3.91f 7.38±4.64a 26.91±2.12cde 83.29±0.15cd 22.65±4.14bc 17.63±7.24cd 5.03±0.18ab 58.43±6.97ab 18.92±0.76abc
N2P2K2 27.05±1.24bcde 14.47±1.12def 16.17±1.71cde 24.24±6.12ef 18.07±2.88a 83.84±0.47de 22.62±6.22bc 17.40±10.87cd 5.22±0.10b 57.53±10.67a 19.85±0.13cdef
N2P3K2 25.44±1.24abcd 10.35±2.55cd 18.02±5.14de 25.12±2.14ef 21.07±3.37ab 83.95±0.87de 14.80±1.04ab 10.20±1.42abcd 4.60±0.49ab 66.94±1.65c 18.26±0.35a
N2P2K0 23.81±0.83ab 24.71±3.61g 17.82±3.57de 11.18±1.90ab 22.49±1.66abc 82.35±0.22b 14.78±2.32ab 10.06±3.95abcd 4.86±0.26ab 65.88±3.56bc 19.34±0.48bcd
N2P2K1 23.63±1.17a 15.07±0.91ef 12.31±1.46bcd 17.67±3.03cd 31.32±2.32e 83.33±0.26cd 12.65±1.13a 8.09±1.90ab 4.56±0.12ab 68.51±1.81c 18.84±0.54abc
N2P2K3 30.18±0.57def 1.70±1.79a 9.83±7.09abc 28.17±3.40f 30.11±3.76de 84.67±0.27ef 17.63±1.61abc 12.53±2.60abcd 5.29±0.19b 63.60±2.75abc 18.77±0.56ab
N3P2K2 22.86±1.00a 23.01±1.72g 16.47±4.45cde 14.88±1.03bc 22.77±2.57abc 81.42±0.13a 10.87±0.80a 5.04±1.29a 5.83±0.10b 69.91±1.73c 19.22±0.37abcd
N1P1K2 34.06±2.81f 2.65±1.85ab 19.86±4.97e 16.82±1.72bcd 26.60±2.96cde 82.97±0.29bc 17.32±1.37abc 13.49±3.22bcd 3.83±2.32a 62.27±2.27abc 20.40±0.18ef
N1P2K1 31.19±2.43ef 3.61±0.60ab 22.15±4.94ef 13.21±4.96abc 29.85±2.62de 84.65±0.31ef 14.81±0.46ab 9.78±0.84abc 5.03±0.22ab 66.22±1.20c 18.97±0.41abc
N2P1K1 29.79±1.18cdef 12.13±1.04de 21.67±3.78ef 11.04±1.19ab 25.37±1.64bcd 83.88±0.26de 15.50±2.18abc 10.30±3.66abcd 5.01±0.33ab 63.79±3.06abc 20.71±0.80f
P值P-value <0.000 1 0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 0.010 0 0.012 1 0.068 0 0.005 2 0.000 2

2.3 NRC模型估测不同施肥处理羊草可消化养分含量和能值

由表4可知,施肥后羊草tdNFC含量多数有所提高,有5个施肥处理显著高于对照(P<0.05),其中N2P0K2处理和N2P1K2处理较高,分别达到241.6和234.49 g/kg DM,分别比对照提高21.05%和17.49%。羊草tdCP含量因施肥变化较为显著,所有施肥处理均显著高于对照(P<0.05),其中高氮肥处理(N3P2K2处理)tdCP含量最高达到84.64 g/kg DM,比对照提高75.13%,表明高氮肥的施入与羊草tdCP含量提高密切相关。从羊草tdNDF含量的变化中发现,在中氮肥和中钾肥处理中,除高磷肥处理(N2P3K2处理)外,均显著低于对照(P<0.05)。从羊草tdFA含量的结果来看,除N3P2K2处理外,所有施肥处理均显著高于对照(P<0.05),其中N1P1K2处理tdFA含量最高达到23.73 g/kg DM,比对照提高121.78%。从羊草TDNm含量的结果来看,4个施肥处理显著高于对照(P<0.05),且以N2P2K0处理最高。此外,各处理羊草DEp、MEp、NElp、NEm和NEg的变化趋势较为一致,其中N2P2K0处理效果较佳。
表4 NRC模型估测不同施肥处理羊草可消化养分含量和能值

Table 4 Estimation of digestible nutrient contents and energy values of Leymus chinensis under different fertilization treatments by NRC model

项目
Items		 真可消化非
纤维碳
水化合物
tdNFC/
(g/kg DM)		 真可消化
粗蛋白质
tdCP/
(g/kg DM)		 真可消化中
性洗涤纤维
tdNDF/
(g/kg DM)		 真可消化
脂肪酸
tdFA/
(g/kg DM)		 维持水平总
可消化养分
TDNm/
(g/kg DM)		 生产水平
消化能
DEp/
(MJ/kg)		 生产水平
代谢能
MEp/
(MJ/kg)		 生产水平
泌乳净能
NElp/
(MJ/kg)		 维持净能
NEm/
(MJ/kg)		 增重净能
NEg/
(MJ/kg)
处理Treatments
N0P0K0 199.58±2.08ab 48.33±2.48a 408.46±11.60bcd 10.70±1.48a 673.44±12.86abc 48.36±0.84ab 48.40±0.85ab 33.83±0.60ab 94.17±5.29ab 97.30±5.80ab
N0P2K2 209.57±4.46abcd 57.06±1.33b 398.86±8.34bcd 15.50±1.04cd 693.35±3.74bcd 49.93±0.28bc 49.98±0.28bc 34.95±0.20bc 104.34±1.90bc 108.46±2.09bc
N1P2K2 223.93±8.39cde 67.97±9.50d 373.43±10.18ab 16.51±0.85d 695.48±15.56bcde 50.33±1.29bc 50.39±1.31bc 35.23±0.92bc 107.22±8.92bc 111.63±9.82bc
N2P0K2 241.60±4.73e 59.55±1.95bc 329.36±11.13a 13.09±0.62b 652.96±14.50a 47.21±1.04a 47.24±1.05a 33.02±0.74a 87.15±6.24a 89.60±6.83a
N2P1K2 234.49±16.70e 64.38±1.77bcd 343.47±41.56a 14.28±0.45bc 667.47±26.58ab 48.32±1.87ab 48.36±1.89ab 33.81±1.33ab 94.17±11.44ab 97.30±12.53ab
N2P2K2 231.38±30.87de 68.20±1.28d 336.42±68.10a 12.93±0.26b 658.08±36.65a 47.77±2.50a 47.80±2.52a 33.41±1.78a 90.98±14.84a 93.82±16.23a
N2P3K2 206.99±6.07abc 65.56±7.89cd 393.75±10.68bc 13.70±0.27b 690.12±8.20bcd 49.91±0.73bc 49.96±0.74bc 34.93±0.52bc 104.21±4.95bc 108.32±5.44bc
N2P2K0 191.83±13.10a 83.52±2.52e 441.59±22.60de 16.51±0.66d 747.08±8.52g 54.25±0.58e 54.34±0.59e 38.01±0.41e 136.59±4.74e 144.06±5.25e
N2P2K1 209.44±4.34abcd 60.65±1.74bcd 397.23±10.62bcd 16.56±0.65d 697.58±6.51cde 50.31±0.42bc 50.36±0.43bc 35.21±0.30bc 106.90±2.92bc 111.27±3.21bc
N2P2K3 197.45±7.90a 58.52±5.00bc 432.39±16.59de 18.52±0.66e 723.03±4.74efg 52.01±0.22cd 52.08±0.22cd 36.42±0.15cd 119.09±1.64cd 124.71±1.81cd
N3P2K2 211.00±5.47abcd 84.64±3.15e 396.95±13.13bcd 11.18±1.19a 710.74±13.11def 51.78±0.97cd 51.85±0.98cd 36.26±0.69cd 117.40±7.13cd 122.85±7.86cd
N1P1K2 225.83±9.59cde 61.97±4.64bcd 361.38±14.02ab 23.73±1.16f 695.57±12.18bcde 50.19±0.92bc 50.25±0.93bc 35.13±0.65bc 106.18±6.34bc 110.49±6.98bc
N1P2K1 220.14±4.97bcde 57.52±2.88bc 395.35±10.28bcd 16.29±0.73d 702.66±5.72cde 50.59±0.41c 50.64±0.42c 35.41±0.29c 108.83±2.87c 113.40±3.15c
N2P1K1 193.12±9.86a 64.12±2.34bcd 442.01±20.18e 18.60±1.06e 734.08±11.09fg 52.90±0.81de 52.98±0.82de 37.05±0.58de 125.92±6.37de 132.25±7.04de
P值
P-value		 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1 <0.000 1

3 讨论

3.1 不同施肥处理羊草营养成分

前人研究表明,不同饲料作物间营养成分的差异(排除作物生长环境因素的影响外)主要来自于作物本身的特性。例如,杨燕燕等[17]分析了国产燕麦、进口燕麦和小黑麦的营养成分差异,结果发现3种牧草中小黑麦的CP含量最高达到9.25%,而国产燕麦和进口燕麦的CP含量为4.26%~4.80%,且无显著差异;高红[23]从东北地区4个不同牧场采集了玉米纤维饲料、大豆皮、甜菜粕和豆渣4种粮食加工副产物,测定其营养成分,其中NPN含量由高到低依次为玉米纤维饲料、豆渣、甜菜粕和大豆皮,PB含量由高到低依次为大豆皮、甜菜粕、豆渣和玉米纤维饲料,PC含量由高到低依次为豆渣、甜菜粕、大豆皮和玉米纤维饲料,可代谢蛋白质(MP)含量由高到低依次为豆渣、大豆皮、甜菜粕和玉米纤维饲料。
不同施肥处理对作物营养价值有显著影响。Jayshri等[26]通过不同氮、钾水平混合施用,探索对饲用高粱氮含量及氮、磷、钾吸收量的影响发现,施氮量显著影响饲用高粱的CP、粗纤维以及叶绿素含量等品质指标。本试验发现,施肥前羊草营养成分含量间存在诸多相关性,但施肥后这种相关性出现减弱,这可能是因为施肥后打破了羊草营养成分之间的固有关系,形成了新的关联,因此可以通过施肥手段打破羊草营养物质间的固有平衡,从而使羊草各营养成分达到所需要的理想状态。
CP含量是羊草的主要营养成分之一,也是衡量羊草营养价值的关键指标。本试验通过“3414”试验方案对不同氮、磷、钾施肥量的羊草营养成分进行分析,结果表明,N3P2K2处理的CP含量最高,这与前人的研究结果[27⇓-29]一致,这也说明氮肥对牧草的CP含量有显著的促进作用;而高钾肥的施入反而会使CP含量降低,这与何飞等[27]的研究结果也相同;不过,本试验在无钾肥的N2P2K0处理中,羊草CP含量仅次于N3P2K2处理,也达到理想效果,这与于铁峰等[28]的研究结论不一致,这可能是由于不同牧草间对钾元素的利用与吸收各不相同,因此对于该方面应该继续深入研究。此外,当作物作为饲料用于饲喂动物时,NDF和ADF含量是与饲料适口性和消化率相关的重要指标[30],饲料NDF和ADF含量越高则被畜禽吸收的营养越少,其中较高含量的ADF可能还会造成反刍动物食糜堆积的现象,从而影响动物进食,阻碍营养物质的吸收[31-32]。本试验中,N2P2K0处理羊草ADF含量最低,而NDF含量最高,这与何飞等[27]的研究结果相一致;而N2P2K3处理羊草的ADF和NDF含量达到双高,这不太利于动物的吸收与利用,这也说明高钾肥施入会提高羊草的纤维含量,因此应该适当控制钾肥的施入量。

3.2 不同施肥处理羊草CNCPS组分

PA在反刍动物的瘤胃内能快速降解,可以提供较高的营养和能量,具有较高的利用价值,但对于单胃动物的营养价值却很低[33]。本试验中,高氮肥处理(N3P2K2处理)羊草PA和PC含量均较低,而PB含量却较高,这说明高氮肥施入所提高的蛋白质含量中多数为可利用蛋白质。同时,高钾肥处理(N2P2K3处理)羊草PA和PC含量很高,PB含量却较低;无钾肥处理(N2P2K0处理)的结果和高氮肥处理的结果较为相似。此外,在PB1含量中,本试验依然发现,高氮肥处理(N3P2K2处理)和无钾肥处理(N2P2K0处理)较高,而高钾肥处理(N2P2K3处理)只有1.70%,这表明钾肥对蛋白质含量提高虽然有一定的促进作用,但是大多数是生成PA和PC,甚至过量的施入还会阻碍蛋白质的生成。
CHO是植物性饲料在反刍动物中的重要营养来源之一,CNCPS将其分为NSC和结构性碳水化合物(structural carbohydrate,SC)两大部分,在此基础之上,根据牧草在动物瘤胃中的降解速度,NSC被划分为CA和CB1,SC被划分为CB2和CC。本试验结果表明,中氮肥和中钾肥的3个处理(N2P0K2处理、N2P1K2处理和N2P2K2处理)中,羊草NSC结果较高,且这3个处理CA含量较高,而CB2含量也都较低,这表明这3种施肥处理有利于提高动物对羊草营养物质的吸收与利用。

3.3 NRC模型估测不同施肥处理羊草可消化养分含量和能值

NRC模型根据饲料的真可消化养分含量估测饲料的能量供给,该模型将饲料中的CHO划分为非纤维碳水化合物(non-fibre carbohydrate,NFC)和纤维碳水化合物(fibre carbohydrate,FC),从而预测不同营养组分对动物能量供给能力的差异[24-25]。本试验中,从羊草tdNFC含量的结果来看,中氮肥和中钾肥的3个处理(N2P0K2处理、N2P1K2处理和N2P2K2处理)tdNFC含量较高,其原因是这3个处理的NFC含量在14个处理中就较高,同时考虑到计算过程中加工校正因子的作用,因此tdNFC含量和NFC含量存在正相关的关系。据报道,饲料中的CP对能量的贡献率主要与CP含量以及ADICP占CP的比例有关[34],本试验中最高tdCP含量的处理与最高CP含量的处理相一致。tdNDF含量与NDF含量密切相关,且呈正相关,在反刍动物瘤胃中一定范围的NDF可以被较好地吸收[35-36],但是不同饲料之间这个规律有所差别[23]。此外,本试验中,各施肥处理羊草TDNm含量、DEp、MEp、NElp、NEm和NEg的变化趋势一致,其中N2P2K0处理效果较佳。

4 结论

① 氮肥对羊草CP含量的提高有着显著的促进作用,但是增加的CP中存在着部分NPN。
② 钾肥在一定程度上制约了氮肥和磷肥对羊草一些营养指标所起的作用,因此钾肥的施入需慎重。
③ 从羊草营养价值综合判断,本试验中N2P2K0处理施肥效果较好。

References

Publishing order | Descend order by publishing year | Descend order by cited within
[1]
刘公社, 李晓霞, 齐冬梅, 等. 羊草种质资源的评价与利用[J]. 科学通报, 2016, 61(2):271-281.

LIU G S, LI X X, QI D M, et al. Evaluation and utilization of sheep grass germplasm resources[J]. Chinese Science Bulletin, 2016, 61(2):271-281. (in Chinese)

[2]
韩忠海, 李晓宇, 张继涛, 等. 外源植物激素对羊草开花习性及结实特征的影响[J]. 中国农学通报, 2019, 35(35):124-128.

DOI

HAN Z H, LI X Y, ZHANG J T, et al. Exogenous plant hormones affect blooming and fruiting characteristics of Leymus chinensis[J]. Chinese Agricultural Science Bulletin, 2019, 35(35):124-128. (in Chinese)

[3]
赵丹丹, 马红媛, 李阳, 等. 水分和养分添加对羊草功能性状和地上生物量的影响[J]. 植物生态学报, 2019, 43(6):501-511.

DOI

ZHAO D D, MA H Y, LI Y, et al. Effects of water and nutrient additions on functional traits and aboveground biomass of Leymus chinensis[J]. Chinese Journal of Plant Ecology, 2019, 43(6):501-511. (in Chinese)

[4]
刘公社, 齐冬梅, 刘辉. 羊草种植实用技术问答[M]. 北京: 中国农业出版社, 2017.

LIU G S, QI D M, LIU H. Q&A on practical technique for sheep grass plantation[M]. Beijing: China Agriculture Press, 2017. (in Chinese)

[5]
RUSSELL J B, O’CONNOR J D, FOX D G, et al. A net carbohydrate and protein system for evaluating cattle diets:Ⅰ.Ruminal fermentation[J]. Journal of Animal Science, 1992, 70(11):3551-3561.

[6]
SNIFFEN C J, O’CONNOR J D, VAN SOEST P J, et al. A net carbohydrate and protein system for evaluating cattle diets:Ⅱ.Carbohydrate and protein availability[J]. Journal of Animal Science, 1992, 70(11):3562-3577.

[7]
FOX D G, SNIFFEN C J, O’CONNOR J D, et al. A net carbohydrate and protein system for evaluating cattle diets:Ⅲ.Cattle requirements and diet adequacy[J]. Journal of Animal Science, 1992, 70(11):3578-3596.

[8]
FOX D G, TEDESCHI L O, TYLUTKI T P, et al. The Cornell net carbohydrate and protein system model for evaluating herd nutrition and nutrient excretion[J]. Animal Feed Science and Technology, 2004, 112(1/2/3/4):29-78.

[9]
TEDESCHI L O, FOX D G, DOANE P H. Evaluation of the tabular feed energy and protein undegradability values of the national research council nutrient requirements of beef cattle[J]. The Professional Animal Scientist, 2005, 21(5):403-415.

[10]
TYLUTKI T P, FOX D G, DURBAL V M, et al. Cornell net carbohydrate and protein system:a model for precision feeding of dairy cattle[J]. Animal Feed Science and Technology, 2008, 143(1/2/3/4):174-202.

[11]
SILVA H M D, OLIVEIRA A S D. A new protein requirement system for dairy cows[J]. Journal of Dairy Science, 2023, 106(3):1757-1772.

[12]
MARTINEAU R, OUELLET D R, PELLERIN D, et al. Ability of three dairy feed evaluation systems to predict postruminal outflows of nitrogenous compounds in dairy cows:a Meta-analysis[J]. Journal of Dairy Science, 2023, 106(12):8583-8610.

[13]
MARTINEAU R, OUELLET D R, PELLERIN D, et al. Ability of three dairy feed evaluation systems to predict postruminal outflows of amino acids in dairy cows:a Meta-analysis[J]. Journal of Dairy Science, 2024, 107(6):3573-3600.

[14]
DONG R L, SUN G Q, YU G H. Estimating in vitro ruminal ammonia-N using multiple linear models and artificial neural networks based on the CNCPS nitrogenous fractions of cattle rations with low concentrate/roughage ratios[J]. Journal of Animal Physiology and Animal Nutrition, 2022, 106(4):841-853.

[15]
THERS H, ERIKSEN J. Annual protein yield and extractable protein potentials in three legumes and two grasses[J]. Journal of the Science of Food and Agriculture, 2021, 102(9):3742-3751.

DOI PMID

[16]
HIGGS R J, CHASE L E, ROSS D A, et al. Updating the Cornell net carbohydrate and protein system feed library and analyzing model sensitivity to feed inputs[J]. Journal of Dairy Science, 2015, 98(9):6340-6360.

DOI PMID

[17]
杨燕燕, 孙宇, 吴春会, 等. 应用CNCPS体系比较饲用小黑麦和燕麦草的营养价值组分[J]. 草地学报, 2022, 30(4):931-935.

DOI

YANG Y Y, SUN Y, WU C H, et al. Applying CNCPS system to evaluate the nutritive value of oat and forage triticale[J]. Acta Agrestia Sinica, 2022, 30(4):931-935. (in Chinese)

[18]
靳玲品. 反刍动物常用粗饲料营养价值评定方法的比较研究[D].硕士学位论文. 北京: 中国农业科学院, 2013.

JIN L P. Comparation of nutritional value evaluation method in common roughage for ruminants[D].Master’s Thesis. Beijing: Chinese Academy of Agricultural Sciences, 2013. (in Chinese)

[19]
周爽, 么恩悦, 苏阔轩, 等. 应用康奈尔净碳水化合物-蛋白质体系法和尼龙袋法评价麦芽根和南瓜籽饼的营养价值[J]. 动物营养学报, 2019, 31(10):4885-4892.

DOI

ZHOU S, YAO E Y, SU K X, et al. Nutritional value of malt root and pumpkin seed cake evaluated by Cornell net carbohydrate and protein system and nylon bag technique[J]. Chinese Journal of Animal Nutrition, 2019, 31(10):4885-4892. (in Chinese)

[20]
兰贵生, 王芳彬, 张智安, 等. 利用康奈尔净碳水化合物-蛋白质体系与聚类分析技术评价油菜秸秆营养价值[J]. 动物营养学报, 2019, 31(4):1877-1886.

LAN G S, WANG F B, ZHANG Z A, et al. Using Cornell net carbohydrate-protein system and cluster analysis technique to evaluate the nutritional value of rape straw[J]. Chinese Journal of Animal Nutrition, 2019, 31(4):1877-1886. (in Chinese)

[21]
郝小燕. 奶牛日粮中玉米纤维饲料与羊草组合替代首蓿干草饲喂效果的研究[D].博士学位论文. 哈尔滨: 东北农业大学, 2017.

HAO X Y. Study on the feeding effects of replacing alfalfa hay with the combination of dry corn gluten feed and Chinese leymus in dairy cows’ ration[D].Ph.D. Thesis. Harbin: Northeast Agricultural University, 2017. (in Chinese)

[22]
张广宁, 刘鑫, 么恩悦, 等. 应用康奈尔净碳水化合物-蛋白质体系和NRC模型评价发酵全混合日粮的营养价值[J]. 动物营养学报, 2019, 31(2):930-939.

ZHANG G N, LIU X, YAO E Y, et al. Evaluation of nutrition values of fermentation total mixed ration using Cornell net carbohydrate-protein system and national research council models[J]. Chinese Journal of Animal Nutrition, 2019, 31(2):930-939. (in Chinese)

[23]
高红. 四种粮食加工副产物对奶牛营养价值的研究[D].硕士学位论文. 哈尔滨: 东北农业大学, 2017.

GAO H. Evaluation of the nutritional values of some alternative feed sources to dairy cows[D].Master’s Thesis. Harbin: Northeast Agricultural University, 2017. (in Chinese)

[24]
VAN SOEST P J. ROBERTSON J B, LEWIS B A. Methods for dietary fiber,neutral detergent fiber,and non-starch polysaccharides in relation to animal nutrition[J]. Journal of Dairy Science, 1991, 74(10):3583-3597.

[25]
NRC. Nutrient requirements of dairy cattle[S].7th ed. Washington,D.C.: The National Academies Press, 2001.

[26]
JAYSHRI D C, PAVAYA R, MALAV J, et al. Effect of nitrogen and potassium on yield,nutrient content and uptake by forage sorghum (Sorghum bicolor (L.) Moench) on loamy sand[J]. International Journal of Chemical Studies, 2018, 6(2):761-765.

[27]
何飞, 赵忠祥, 康俊梅, 等. 氮磷钾配比施肥对紫花苜蓿草产量及品质的影响[J]. 中国草地学报, 2019, 41(5):24-32.

HE F, ZHAO Z X, KANG J M, et al. Effects of N,P and K fertilizer on alfalfa hay yield and quality[J]. Chinese Journal of Grassland, 2019, 41(5):24-32. (in Chinese)

[28]
于铁峰, 刘晓静, 吴勇, 等. 西北干旱灌区紫花苜蓿高产田施肥效应及推荐施肥量研究[J]. 草业学报, 2019, 28(8):15-27.

DOI

YU T F, LIU X J, WU Y, et al. Fertilization effect of alfalfa high yield field and its recommended fertilizer application in northwest drought irrigated area[J]. Acta Prataculturae Sinica, 2019, 28(8):15-27. (in Chinese)

[29]
周镇磊, 刘建明, 曹东, 等. “3414”施肥对呼伦贝尔燕麦产量和品质的影响[J]. 分子植物育种. 2022:1-25(2022-09-21) [2024-06-05]. http://kns.cnki.net/kcms/detail/46.1068.S.20220920.1656.006.html

ZHOU Z L, LIU J M, CAO D, et al. Effect of “3414” Fertilization on yield and quality of oats in Hulun Buir[J]. Molecular Plant Breeding, 2022:1-25.(2022-09-21) [2024-06-05]. http://kns.cnki.net/kcms/detail/46.1068.S.20220920.1656.006.html in Chinese)

[30]
徐敏云, 李建国, 谢帆, 等. 不同施肥处理对青贮玉米生长和产量的影响[J]. 草业学报, 2010, 19(3):245-250.

XU M Y, LI J G, XIE F, et al. Effect of different fertilizer applications on silage maize growth and hay output[J]. Acta Prataculturae Sinica, 2010, 19(3):245-250. (in Chinese)

[31]
DETMANN E, GIONBELLI M P, HUHTANEN P. A Meta-analytical evaluation of the regulation of voluntary intake in cattle fed tropical forage-based diets[J]. Journal of Animal Science, 2014, 92(10):4632-4641.

DOI PMID

[32]
琚思思, 纪守坤, 段春辉, 等. 不同NDF水平饲粮对羔羊生长性能、营养物质消化、消化道重量及瘤胃乳头发育的影响[J]. 畜牧兽医学报, 2020, 51(7):1666-1676.

DOI

JU S S, JI S K, DUAN C H, et al. Effects of diet with different NDF levels on growth performance,nutrient digestion,digestive tract weight and rumen papilla development of lambs[J]. Acta Veterinaria et Zootechnica Sinica, 2020, 51(7):1666-1676. (in Chinese)

[33]
周俊华, 邹彩霞, 梁贤威, 等. 应用康奈尔净碳水化合物-蛋白质体系评定广西水牛常用粗饲料的营养价值[J]. 动物营养学报, 2011, 23(12):2190-2197.

ZHOU J H, ZOU C X, LIANG X W, et al. Evaluation of nutritive value of common roughages for Guangxi water buffalo by Cornell net carbohydrate and protein system[J]. Chinese Journal of Animal Nutrition, 2011, 23(12):2190-2197. (in Chinese)

[34]
刘宁宁, 许庆方, 郭刚, 等. 应用CNCPS体系评价早熟、晚熟燕麦品种的品质[J]. 草业科学, 2020, 37(10):2049-2056.

LIU N N, XU Q F, GUO G, et al. Application of the Cornell net carbohydrate and protein system to evaluate the quality of early and late maturing oats[J]. Pratacultural Science, 2020, 37(10):2049-2056. (in Chinese)

[35]
BIRICIK H, GENCOGLU H, BOZAN B, et al. The effect of dry corn gluten feed on chewing activities and rumen parameters in lactating dairy cows[J]. Italian Journal of Animal Science, 2007, 6(1):61-70.

[36]
KELZER J M, KONONOFF P J, TEDESCHI L O, et al. Evaluation of protein fractionation and ruminal and intestinal digestibility of corn milling co-products[J]. Journal of Dairy Science, 2010, 93(6):2803-2815.

DOI PMID

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