Effects of antioxidant‑rich Lactiplantibacillus plantarum inoculated alfalfa silage on rumen fermentation, antioxidant and immunity status, and mammary gland gene expression in dairy goats

Background Milk synthesis in lactating animals demands high energy metabolism,which results in an increased production of reactive oxygen metabolites(ROM)causing an imbalance between oxidants and antioxidants thereby inducing oxidative stress(OS)on the animals.To mitigate OS and postpartum disorders in dairy goats and gain insight into the impact of dietary choices on redox status during lactation,a feeding trial was conducted using alfalfa silage inoculated with a high-antioxidant strain of Lactiplantibacillus plantarum.Methods Twenty-four Guanzhong dairy goats(38.1±1.20 kg)were randomly assigned to two dietary treatments:one containing silage inoculated with L.plantarum MTD/1(RSMTD-1),and the other containing silage inoculated with high antioxidant activity L.plantarum 24-7(ES24-7).Results ES24-7-inoculated silage exhibited better fermentation quality and antioxidant activity compared to RSMTD-1.The ES24-7 diet elevated the total antioxidant capacity(T-AOC),superoxide dismutase(SOD),glutathione peroxi-dase(GSH-Px),and catalase(CAT)activities in milk,serum,and feces of lactating goats(with the exception of T-AOC in milk).Additionally,the diet containing ES24-7 inoculated silage enhanced casein yield,milk free fatty acid(FFA)content,and vitamin A level in the goats’milk.Furthermore,an increase of immunoglobulin(Ig)A,IgG,IgM,inter-leukin(IL)-4,and IL-10 concentrations were observed,coupled with a reduction in IL-1β,IL-2,IL-6,interferon(IFN)-γ,and tumor necrosis factor(TNF)-αconcentrations in the serum of lactating goats fed ES24-7.Higher concentrations of total volatile fatty acid(VFA),acetate,and propionate were observed in the rumen fluid of dairy goats fed ES24-7 inoculated silage.Moreover,the diet containing ES24-7 inoculated silage significantly upregulated the expression of nuclear factor erythroid 2 like 2(NFE2L2),beta-carotene oxygenase 1(BCO1),SOD1,SOD2,SOD3,GPX2,CAT,glu-tathione-disulfide reductase(GSR),and heme oxygenase 1(HMOX1)genes in the mammary gland,while decreased the levels of NADPH oxidase 4(NOX4),TNF,and interferon gamma(IFNG).Conclusions These findings indicated that feeding L.plantarum 24-7 inoculated alfalfa silage not only improved rumen fermentation and milk quality in lactating dairy goats but also boosted their immunity and antioxidant status by modulating the expression of several genes related to antioxidant and inflammation in the mammary gland.

Development of a single transcript CRISPR/Cas9 toolkit for efficient genome editing in autotetraploid alfalfa

Alfalfa(Medicago sativa.L.)is a globally significant autotetraploid legume forage crop.However,despite its importance,establishing efficient gene editing systems for cultivated alfalfa remains a formidable challenge.In this study,we pioneered the development of a highly effective ultrasonic-assisted leaf disc transformation system for Gongnong 1 alfalfa,a variety widely cultivated in Northeast China.Subsequently,we created a single transcript CRISPR/Cas9(CRISPR_2.0)toolkit,incorporating multiplex gRNAs,designed for gene editing in Gongnong 1.Both Cas9 and gRNA scaffolds were under the control of the Arabidopsis ubiquitin-10 promoter,a widely employed polymeraseⅡconstitutive promoter known for strong transgene expression in dicots.To assess the toolkit’s efficiency,we targeted PALM1,a gene associated with a recognizable multifoliate phenotype.Utilizing the CRISPR_2.0 toolkit,we directed PALM1 editing at two sites in the wild-type Gongnong 1.Results indicated a 35.1%occurrence of editing events all in target 2 alleles,while no mutations were detected at target 1 in the transgenic-positive lines.To explore more efficient sgRNAs,we developed a rapid,reliable screening system based on Agrobacterium rhizogenes-mediated hairy root transformation,incorporating the visible reporter MtLAP1.This screening system demonstrated that most purple visible hairy roots underwent gene editing.Notably,sgRNA3,with an 83.0%editing efficiency,was selected using the visible hairy root system.As anticipated,tetra-allelic homozygous palm1 mutations exhibited a clear multifoliate phenotype.These palm1 lines demonstrated an average crude protein yield increase of 21.5%compared to trifoliolate alfalfa.Our findings highlight the modified CRISPR_2.0 system as a highly efficient and robust gene editing tool for autotetraploid alfalfa.

Variation Characteristics of Root Traits of Different Alfalfa Cultivars under Saline-Alkaline Stress and their Relationship with Soil Environmental Factors

Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of yield.It is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil environments.In this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment group.At the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried out.The results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline stress.There was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline stress.The number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control group.The ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(p<0.05).The root fresh weight(RFW)and dry weight(RDW),root length(RL),RV and RT of alfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase activity(BGC)and acid phosphatase activity(APC)(p<0.05).This study improved knowledge of the relationship between root traits and soil environmental factors and offered a theoretical framework for elucidating how plant roots adapt to saline-alkaline stressed soil environments.

Flavonol synthase gene MsFLS13 regulates saline-alkali stress tolerance in alfalfa

Alfalfa(Medicago sativa L.) is one of the most extensively grown leguminous forage worldwide.Environmental saline-alkali stress significantly influences the growth,development,and yield of alfalfa,posing a threat to its agricultural production.However,little is known about the potential mechanisms by which alfalfa responds to saline-alkali stress.Here,we investigated these mechanisms by cloning a saline-alkali-induced flavonol synthase gene(Ms FLS13) from alfalfa,which was previously reported to be significantly upregulated under saline-alkali stress,and examining its function in the saline-alkali response.Overexpression of Ms FLS13 in alfalfa promoted plant tolerance to saline-alkali stress by enhancing flavonol accumulation,antioxidant capacity,osmotic balance,and photosynthetic efficiency.Conversely,Ms FLS13 inhibition using RNA interference reduced flavonol synthase activity and inhibited hairy root growth under saline-alkali stress.Yeast one-hybrid and dual-luciferase reporter assays indicated that the R2R3-MYB Ms MYB12 transcription factor activates Ms FLS13 expression by binding to the MBS motif in the Ms FLS13 promoter.Further analysis revealed that abscisic acid mediates the salinealkali stress response partially by inducing Ms MYB12 and Ms FLS13 expression,which consequently increases flavonol levels and maintains antioxidant homeostasis in alfalfa.Collectively,our findings highlight the crucial role of Ms FLS13 in alfalfa in response to saline-alkali stress and provide a novel genetic resource for creating saline-alkali-resistant alfalfa through genetic engineering.

Overexpression of ZxABCG11 from Zygophyllum xanthoxylum enhances tolerance to drought and heat in alfalfa by increasing cuticular wax deposition

Drought and heat stresses cause yield losses in alfalfa,a forage crop cultivated worldwide.Improving its drought and heat tolerance is desirable for maintaining alfalfa productivity in hot,arid regions.Cuticular wax forms a protective barrier on aerial surfaces of land plants against environmental stresses.ABCG11encodes an ATP binding cassette(ABC) transporter that functions in the cuticular wax transport pathway.In this study,Zx ABCG11 from the xerophyte Zygophyllum xanthoxylum was introduced into alfalfa by Agrobacterium tumefaciens-mediated transformation.Compared to the wild type(WT),transgenic alfalfa displayed faster growth,higher wax crystal density,and thicker cuticle on leaves under normal condition.Under either drought or heat treatment in greenhouse conditions,the plant height and shoot biomass of transgenic lines were significantly higher than those of the WT.Transgenic alfalfa showed excellent growth and 50% greater hay yield than WT under field conditions in a hot,arid region.Overexpression of Zx ABCG11 up-regulated wax-related genes and resulted in more cuticular wax deposition,which contributed to reduction of cuticle permeability and thus increased water retention and photosynthesis capacity of transgenic alfalfa.Thus,overexpression of Zx ABCG11 can simultaneously improve biomass yield,drought and heat tolerance in alfalfa by increasing cuticular wax deposition.Our study provides a promising avenue for developing novel forage cultivars suitable for planting in hot,arid,marginal lands.

Effects of Different Herbicides on Weed Control in Alfalfa Field

[Objectives]The paper was to systematically study the technology of weed control in alfalfa field.[Methods]Reviving alfalfa field and newly sown alfalfa field after emergence were selected,and the effects of different herbicides on weed control and alfalfa yield were discussed.[Results]The optimal herbicides after alfalfa reviving were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 1.05 L/hm 2,respectively.The optimal herbicides after emergence of newly born alfalfa were 5%imazethapyr and 10%imazethapyr,and the optimal dosages were 1.5 and 0.75 L/hm 2,respectively.[Conclusions]This study will provide a technical support for high quality production of alfalfa.

Bale Density and Moisture Content Effects on the Losses of Baled Alfalfa

In order to reduce alfalfa losses, the effect of bale density and alfalfa moisture content on the losses of baled alfalfa during the baling and transportation process was determined in this study. Three ranges of moisture content including 14%-17%, 17% -20%, and 20%-23% （wb） were considered in this study. Bale densities considered in this research were 110-120, 120-130, 130-140, and 140-150 kg/m3. The study was conducted in the form of a split-plot experimental design with three replications and a small rectangular baler was used to bale the second cut alfalfa. Alfalfa losses were measured in the pickup system and compression chamber of baler and losses were separated to stems and leaves. Alfalfa losses were also determined during the bale transportation process. Results showed that alfalfa moisture content had significant effect on the leaf and stem losses of the baler pickup system and alfalfa losses during the transportation process while; leaf and stem losses of baler compression chamber were not affected by alfalfa moisture content. Results also revealed that the bale density had no significant effect on the leaf and stem losses of the baler pickup system and alfalfa losses during the transportation process but leaf and stem losses of baler compression chamber were significantly affected by the bale density.

Effect of Space Flight Factors on Plant Biomass Developed from Alfalfa Seeds Carried by the Satellite

[Objective] The aim of this study was to investigate the effect of space flight factors on plant biomass in the generation of alfalfa carried by the satellite.[Method]Seeds from three lines of alfalfa were carried by the seed-breeding satellite Shijian-8.After the satellite returned to the ground,stem diameter,primary branch number and current-year individual biomass of alfalfa were studied.[Result]After space flight,primary branch number and current-year individual biomass of alfalfa increased significantly,while the stem diameter had no significant change.Using the value over(the mean value of control + three standard deviation)as a criterion to screen,the variants with enlarged stem diameter,increased primary branch number and individual biomass was two,five and twelve respectively.[Conclusion]The obtained variants can be used in the variety improvement of alfalfa and its new variety breeding,but whether its favorable variation can inherit stably to the progenies needs further study.

Application of Oats to Control the Weeds in the Seedling Period of Alfalfa Sowed in Spring

[Objective]The aim was to solve the weeds existed in seedling period of alfalfa in Chongqing.[Method]The naked oat and common oat were selected.Through the analysis of determiners such as plant number,plant height,yield and weeds ratio,the oat type and sowing method were screened through all the accompany sowing crops to better control weeds in the seedling period of alfalfa.[Result]Compared with common oat,the tested naked oat as the companion crop of alfalfa seeding can prevent weeds more effectively;the proper companion-seeding disposal of alfalfa sowed in spring in Chongqing area was 15 kg/hm2 of alfalfa and 120 kg/hm2 of naked oat,sowing in strip in 40 cm row spacing;the proper mowing period of oat was during the time from May 11th to May 21st;the proper mowing period of alfalfa was ten days later.[Conclusion]Spring sowing oats with alfalfa can control seedling weeds effectively.

Traits Analysis and Evaluation on Several Alfalfa Varieties

The agronomic and qualitative traits of 17 alfalfa varieties were analyzed in field and lab from 2006 to 2008, and these traits were evaluated by principal component analysis and cluster analysis. A total of 10 main traits were classified as five factors： growth factor, quality factor, stem and leaf factors, plant factor and yield factor. These five factors and their correlation were selected for breeding. These 17 varieties can be divided into five clusters. The domestic varieties have better agronomic traits, while the introduced ones have better qualitative traits.

Study on Spatial Distribution Pattern of Thrip (Odentot hrips lati) on Alfalfa (Medicago sativa)

[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip（Odentot hrips lati） on alfalfa（Medicago sativa）.[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in size.During bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei＇s method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical level.During the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties.

China’s alfalfa market and imports: Development, trends, and potential impacts of the U.S.-China trade dispute and retaliations

This study examines the development and trends of China’s alfalfa market and imports, identifies key factors for the rapid increase in China’s alfalfa imports, and discusses potential impacts of the U.S.-China trade dispute and retaliations on the alfalfa markets and trade in both nations. China’s rapid transition toward larger-scale commercial dairy production, with enhanced feed and cost management as well as quality and safety control, and its limited resources for high-quality alfalfa production are key factors for the dramatic increase in its alfalfa imports, from 19 601 metric tons in 2008 to 1.38 million metric tons(mmt) in 2018. While the United States dominated China’s alfalfa imports with an average share of 97.01% from 2007 to 2017, the share dropped to 83.76% in 2018 and 63.28% in January 2019 due to the trade dispute and retaliations started in 2018. China will likely remain a large importer of alfalfa because of both its growing demand and the comparative advantages of imported alfalfa in quality and price, but the imports from the United States will be highly affected by the ongoing trade dispute and negotiations. China is also expected to make more efforts to reduce its dependence on U.S. alfalfa through increased investment in domestic alfalfa production and identification of alternative sources of alfalfa and other hay imports.

Growth Performance of Alfalfa(Medicago sativa)under Different Nitrogen Application Levels

Nitrogen addition is rather important to the growth of alfalfa. In this study, the effects of different nitrogen application levels on various growth characteristics of alfalfa were investigated. The results showed that nitrogen application exhibited no significant effects on plant height and stem diameter but posed significant effects on branch number of alfalfa. Branch number of alfalfa in each cutting raised with the increasing application level of nitrogen, with significant differences among different treatments （P〈0.05）; individual aboveground biomass increased with the increasing application level of nitrogen, but the increasing trend gradually tended to be steady from the first to the fourth cutting. Nitrogen application affected significantly （P〈0.05） individual aboveground biomass of alfalfa in the first, second and fourth cutting, but exhibited no significant effects on individual aboveground biomass of alfalfa in the third cutting. With the increase of nitrogen application level, total surface area, total volume, collar diameter and crossing number of alfalfa roots increased gradually, but total length, average diameter and furcating number of alfalfa roots increased first and then declined. Total length, average diameter and furcating number of alfalfa roots reached the maximum in N60 treatment.

Photosynthesis and Transpiration Characters of Alfalfa (Medicago sativa) and Their Relationship with Relevant Factors during Branching Stage

[ Objective] The paper presents the diumal changes of photosynthesis and transpiration of different alfalfa varieties and their relationship with the associated physiological and ecological factors during branching stage, so as to provide a basis for the development, utilization, and breed- ing of alfalfa. [ Method] Under natural conditions, the diurnal changes of net photosynthetic rate （Pn）, transpiration rate （Tr）, the relevant physio- logical factors including leaf temperature （TI）, stomatal conductance （Gs） and intemal COn concentration （Ci）, as well as the relevant physiologi- cal factors including photosynthetic available radiation （PAR）, CO2 concentration in field （Ca） and air temperature （Ta） were measured in four al- falfa varieties （Algonguin, WL323 HQ, WL414, and Millionaire）. The water use efficiency （WUE） and light use efficiency （LUE） were calculated, and the correlation among them was also analyzed. [Result] The Pn, Tr, PAR and Ta of the four varieties appeared to vary in a single-peak curve; the sequence of WUE was WL323 HQ ~ Algonguin ~ WL414 ~ Millionaire; there was no significant difference in LUE of the four alfalfa varieties; coef- ficient analysis showed that Pn was mainly affected by PAR, Gs, and Ci, while Tr by PAR and Ta. [ Conclusion] WL323 HQ is the variety with high Pn, high WUE and low Tr, and it has strong adaptability to drought. In four alfalfa varieties, PAR, Ta, Gs, and TI are the primary determining fac- tors while Ca and Ci the limiting factors of Tr; Gs is the primary determining factor while Ci the limiting factor of Pn.

Study on the Correlation Between Leaf Area and Drought Resistance in Different Alfalfa Varieties

[Objective] This study was to reveal the correlation between leaf area and drought resistance in different varieties of alfalfa.[Method] Using various alfalfa varieties as experimental materials,the drought resistance of leaves of drought-stressed alfalfa plants was assessed by measuring the content of free proline for analyzing its correlation with leaf area.[Result] Under drought condition,the drought resistance of alfalfa is directly related to leaf area in a positive correlation.[Conclusion] Leaf area could be used as an institutional assistant index to reflect the resistance of different alfalfa varieties.

Separation and Screening of Biocontrol Actinomyces against Alfalfa Root Rot

[Objective] Actinomycetes with high antagonistic effects on alfalfa root rot pathogen was isolated from 10 soil samples in Chifeng Inner Mongolia. [Method] 91 actinomyces were separated from 10 soil samples in Chifeng Inner Mongolia by gradient dilution separation method. In duel culture tests, all isolates were tested for their antagonism by using 3 strains including Fusarium solani, F. oxysoporum, F. avenaceum of alfalfa root rot pathogenic bacteria as indicator strains. [Result] 5 strains with strong antagonistic effect on tested alfalfa root rot pathogen were obtained from No.1, No.4, No.6 and No.7 soil samples which were numbered 1-3-6, 4-4-2, 6-2-27 and 7-2-13 respectively, accounted for 5.50% in separated strains. [Conclusion] This study laid certain foundation for biological control of alfalfa root rot disease.

Bioinformatics Analysis of Zinc Transporter from Baoding Alfalfa

[Objective] This study aimed to perform the bioinformatics analysis of Zinc transporter （ZnT） from Baoding Alfalfa. [Method] Based on the amino acid sequence, the physical and chemical properties, hydrophilicity/hydrophobicity, secondary structure of ZnT from Baoding alfalfa were predicted by a series of bioinformatics software. And the transmembrane domains were predicted by using different online tools. [Result] ZnT is a hydrophobic protein containing 408 amino acids with the theoretical pl of 5.94, and it has 7 potential transmembrane hydrophobic regions. In the sec- ondary structure, co-helix （Hh） accounted for 48.04%, extended strand （Ee） for 9.56%, random coil （Cc） for 42.40%, which was accored with the characteristic of transmembrane protein. [Conclusion] mZnT is a member of CDF family, responsible for transporting Zn^2＋ out of the cell membrane to reduce the concentration and toxicity of Zn^2＋.

Research Progress on Alfalfa(Medicago sativa L.) Adaptability under Drought Stress

Alfalfa （Medicago sativa L） is one of the most important leguminous forage in China, and distributed most widely in the world. Because of Its high nutritional value, large biomass and strong reproducibility and improved soil green ma- nure plants, it is a kind of green manure plant capable of improving soil and known as ＂the king of forage＂. Alfalfa has strong adaptability under drought stress, and could adapt drought conditions through its physiological metabolism, structure devel- opment and morphology construction. Drought resistance in alfalfa is always a hot research subject of forage, and the research has been gradually developed from the morphological level to more-deeply physiological, biochemical and molecular biology fields, and has made many valuable research achievements.

Alfalfa-containing diets alter luminal microbiota structure and short chain fatty acid sensing in the caecal mucosa of pigs

Background: Pork produced by outdoor-reared pigs raised mostly on alfalfa pastures attracts increasing population of consumer from most of the world. In China, pigs were raised with alfalfa-containing diets to seek for good quality pork.However, the influence of dietary alfalfa involving high level of insoluble dietary fiber(IDF) on pig intestinal luminal microbiota composition remains unclear. The objective of this study was to investigate the effects of alfalfa on luminal microbiota and short chain fatty acids(SCFA) production, and gene expressions involved in SCFA sensing, transporting and absorbing in pig caecal mucosa.Results: Twenty-four growing pigs were randomly allotted to four diets containing 0%, 5%, 10% and 15% alfalfa meal for a 28-d experiment. Ingestion of alfalfa meal-contained diets significantly increased the ratio of body weight gain to feed consumption. Illumina MiS eq sequencing of the V3 region of the 16 S r RNA genes showed that alfalfa-containing diet significantly decreased the relative abundance of genera Turicibacter, Acidiphilium, Paracoccus, Propionibacterium,Corynebacterium, Pseudomonas, Acinetobacter, and Staphylococcus, and increased the relative abundance of genera Lachnospira, Marvinbryantia, and Desulfovibrio in the caecal digesta. Butyrate concentration was significantly increased in the hindgut by the supplementation of alfalfa meal in diets. The m RNA gene expressions of FFAR3, SMCT1, MCT1,PYY, and GCG were significantly increased in the caecal mucosa of pigs fed alfalfa meal.Conclusions: Our results suggested that alfalfa-containing diet has exerted significant impacts on caecal microbiota composition, butyrate concentration and significantly upregulated m RNA expression of host caecal mucosal genes involved in SCFA sensing and absorption as well as regulation of satiety.

Effect of Graded Levels of Fiber from Alfalfa Meal on Nutrient Digestibility and Flow of Fattening Pigs

The fiber level and composition have an important effect on nutrient digestibility of swine diets. Little information is known about the effects of fiber level and composition from alfalfa meal on nutrient digestibility of fattening pigs fed a corn-soybean meal-based diet. The objective of this experiment was to determine the effects of alfalfa fiber on the growth performance, intestinal nutrient flow and apparent total tract digestibility（ATTD） of nutrients in fattening pigs. 24 barrows（Duroc×（Large White×Landrace）, body weight=（60.6±0.7） kg） were randomly allotted to 4 treatments with 6 replicates of 1 pig per replicate. The pigs were provided a control diet or a diet containing 5, 10 or 20% of alfalfa meal during a 14-d experiment period. Average daily gain（ADG） and the ATTD of dry matter（DM）, organic matter（OM）, crude protein（CP）, neutral detergent fiber（NDF）, acid detergent fiber（ADF） and gross energy（GE） reduced linearly as the level of alfalfa meal in the diet increased（P〈0.01）. The total tract flow of DM, OM, CP, NDF, ADF, and GE increased with the increase in dietary alfalfa（linear, P〈0.05）. Growth performance and nutrient digestion were not affected by inclusion of 5% alfalfa meal in the diet（P〉0.05）. A multiple linear regression analysis, taking into account both soluble and insoluble fiber intake, explained approximately 70% of the variation in the ATTD of DM, OM, NDF, and GE（P〈0.01）. In conclusion, alfalfa meal should be limited to less than 5% of the diet in fattening pigs to maximize growth performance and nutrient digestion. Soluble and insoluble fiber from alfalfa meal has the differential roles in nutrient digestion, which may help explain the main variation observed in nutrient digestibility. These findings suggest that knowledge of specific fiber components is necessary to accurately predict the effects of dietary fiber on nutrient digestibility.