Acid Detergent Fiber Content Research Articles

Nutritional Evaluation of Milk Thistle Meal as a Protein Feedstuff for Diets of Dairy Cattle.

The objective of this work is to investigate the chemical and nutritional value of milk thistle meal (MTM) in order to improve it and to provide theoretical support for its application in dairy cattle production. MTM was assessed in comparison with seven conventional protein feed sources, namely, soybean meal (SBM), cottonseed meal (CS), canola meal (CN), palm kernel meal (PK), rice bran meal (RB), corn germ meal (CG), and sesame meal (SS). The chemical composition of these feedstuffs was assessed using wet chemical analysis, the Cornell Net Carbohydrate and Protein System was used to evaluate the carbohydrate and protein fractions, and the in situ nylon bag technique and the modified three-step in vitro method were used to assess the rumen degradation and intestinal digestibility. Additionally, Fourier transform infrared technology was used to determine the feedstuff protein spectral molecular structure and its amino acid profile was also assessed. The result showed that MTM acid detergent fiber, lignin, unavailable nitrogen, and non-degradable carbohydrate content were higher than those of the other feedstuffs. It had a 17% and 36% rumen effective degradation rate of neutral detergent fiber and dry matter, respectively, and had the lowest small intestinal rumen undegradable protein digestibility rate. It was low in leucine, histidine, arginine, and proline, but high in methionine. The total area of amide I and amide II in the protein secondary structure was similar to that of CN and CS, and the amide I and II ratio was not different from that of RB. To sum up, MTM has a poor carbohydrate composition and is high in fiber but, in comparison to most other protein feeds, has a higher crude protein rumen effective degradation rate, similar to that of SBM, and it is a good source of methionine, a limiting amino acid. Hence, its nutritional value can be further improved for application in dairy feeding through processes such as microbial or enzymatic fermentation.

Effect of Defoliation on Growth, Yield and Forage Quality in Maize, as a Simulation of the Impact of Fall Armyworm (Spodoptera frugiperda)

This study assesses the impact of defoliation applied to three developmental stages across three cropping seasons from 2021 to 2023 on growth, yield and forage quality in maize. The experimental design included three treatments: defoliation of three expanded leaves at the 3rd–4th leaf stage (DF1), the 5th–6th expanded leaves by leaf punch (DF2) and expanding leaves with the DF2 treatment (DF3) at the 6th–7th leaf stages, compared with no defoliation (control). Over three years, the most significant decrease in dry matter (DM) yield occurred in DF1 during spring sowing, while in summer sowing, the largest reduction was in DF3, both of which were correlated with changes in the number of grains per ear. The DM yields at harvest were positively correlated with plant leaf areas at the silking stage. The digestibility of forage in in vitro DM decreased concomitantly with an increase in acid detergent fiber content, indicating a decrease in forage quality. Given the frequent severe damage observed in summer sown maize and the detrimental effects of early growth stage leaf feeding on quality and quantity of spring sown maize, the application of registered insecticides is advised to reduce pest damage to maize crops.

Effects of selenium enrichment on fermentation characteristics, selenium content and microbial community of alfalfa silage

BackgroundSelenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage.ResultsIn this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05).ConclusionThis study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.

Maximizing food equivalent unit yield for forage maize production without notably compromising dry matter yield and feed quality in a semi-arid region

Food equivalent unit (FEU) is a vector used to measure the value of food based on its calorie and protein content and their digestibility. However, the optimal planting density and N application rate for maximizing the FEU yield (FEUY) of forage maize (Zea mays L.) is still poorly understood in the fast-growing animal husbandry regions of the Chinese Loess Plateau. Here, a 2-year consecutive field experiment was conducted to explore the impacts of planting density, N application rate, and their interactions on growth, dry matter yield (DMY), forage quality, and FEUY of a dominant forage maize cultivar. Planting density significantly affected the stem diameter, LAI, DMY, and dry matter allocation (DMA) of the leaf. Initially, increasing the N rate increased the stem diameter, LAI, FEUY, and DMY of forage maize and then decreased. The stem diameter, LAI, FEUY and above-ground DMY peaked under 180 kg∙ha−1 N in both years. Moreover, N application significantly increased the crude protein content of the whole plant and decreased the acid detergent fiber content. The surface fittings of the 2-year study indicated that 110,000 plants∙ha−1 (plant density) and 171.2 kg∙ha−1 (N rate) obtained the greatest DMY (19.0 t∙ha−1). The grade index (a comprehensive evaluation index for forage quality) peaked at 15.4 MJ∙d−1 under 94,000 plants ha−1 and 270 kg∙ha−1. The 110,000 plants∙ha−1 plant density and 181.5 kg∙ha−1 N rate jointly maximized the FEUY (11,125.4 FEU∙ha−1), maintaining 99.9 % of the maximum DMY and 97.5 % of the maximum grade index. Thus, 110,000 plants∙ha−1 plant density and 181.5 kg∙ha−1 N rate are recommended for high-productivity forage maize production, without notably compromising dry matter yield and feed quality. This research is conducive to advancing the coordinated development of forage crop cultivation and herbivorous livestock farming in semi-arid rainfed areas.

Two‐cut system suggested for tall wheatgrass to balance herbage yield and quality in the coastal saline–alkaline land around the Bohai Sea

AbstractBackgroundTall wheatgrass is a perennial salt‐tolerant bunchgrass, which is a promising candidate for establishing a “Coastal Grass Belt” in China, particularly in the coastal saline–alkaline soils surrounding the Bohai Sea.MethodsSeven harvesting treatments were performed to explore the optimal harvesting time and frequency for tall wheatgrass in coastal area. The dry matter yield (DMY) and forage nutritional values were investigated for each cut. The correlation between harvesting time and frequency thereof among the investigated traits was also determined.ResultsThe results showed that the two‐cut on June 18 and October 29 produced the highest DMY. Another two‐cut on May 26 and October 29 produced a relatively high crude protein (CP) yield. The DMY, contents of neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude cellulose (CC) as well as CP yield were positively correlated to plant height, while the CP content and the relative feed value (RFV) were negatively correlated to plant height. The accumulating growing degree days, accumulated precipitation, and sunshine duration were positively correlated with plant height, DMY, contents of NDF, ADF, and CC as well as CP yield, but negatively correlated with CP content and RFV for the first cut.ConclusionsThe two‐cut treatment at the end of May and October may be suitable for tall wheatgrass in the “Coastal Grass Belt” targeted area.

Comprehensive assessment of turfgrass wear tolerance: A study on mechanical and chemical traits

A key criterion in the selection process for turfgrass breeding is effective wear tolerance, indicating the plant's capacity to endure forces that may impact leaves, stems, crowns, and roots. In this study, the correlation between mechanical and chemical traits and the wear tolerance of 37 cultivars belonging to seven turfgrass species was examined. Mechanical properties and fiber characteristics of wide range of turfgrass cultivars were determined and compared for the first time. The evaluation of turf wear tolerance (described as turf cover index, TCI) was conducted through a three-year field trial using a Brinkman traffic simulator. Tensile tests were conducted to determine biomechanical parameters. According to the TCI, the most wear-resistant cultivars were those of Lolium perenne, Most of these cultivars demonstrated a TCI below 0.1. The cultivar 'Nira' was the most resistant, with a TCI of − 0.285. The least resilient cultivars belonged to Festuca ovina and Festuca rubra, all exhibiting TCI values above 0.6. Agrostis stolonifera and Agrostis capillaris were characterised by lower cellulose and acid detergent fiber content but high hemicellulose content. The opposite result was determined for Festuca rubra and Festuca ovina. The highest hemicellulose ratio was obtained for Poa pratensis. Lolium perenne was characterised by relatively high content of cellulose, lignin and hemicellulose. Cultivars of Festuca arundinace distinctly differed from other cultivars, demonstrating higher mechanical resistance with an average force-to-break of 3.73 N. Cultivars of Agrostis stolonifera and Agrostis capillaris reached force-to-break values up to 1.0 N. The relationships between TCI and fiber composition of turfgrass leaves were significant for crude fiber, NDF and hemicellulose content. Thus higher NDF and hemicellulose content resulted in higher force-to-break and work-to-break parameters.

Enhancing quality of ruminant feed through fungal treatment: Usage of bamboo shoot residues.

In this investigation, we explore the harnessing of bamboo shoot residues (BSR) as a viable source for ruminant feed through fungal treatment, with the overarching objective of elevating feed quality and optimizing bamboo shoot utilization. The white-rot fungi (Wr.fungi), Aspergillus niger (A.niger), and its co-cultures (A.niger&Wr.fungi) were employed to ferment BSR. And the impact of different fermentation methods and culture time on the chemical composition (Crude protein Ash, neutral detergent fibre and acid detergent fibers), enzyme activity (Cellulase, Laccase, Filter paperase and Lignin peroxidase activities), and rumen digestibility in vitro were assessed. The findings reveal a nota ble 30.39% increase in crude protein in fermented BSR, accompanied by respective decreases of 13.02% and 17.31% in acid detergent fiber and neutral detergent fibre content. Enzyme activities experienced augmentation post-fermentation with A.niger&Wr.fungi. Specifically, the peak Cellulase, Laccase, and Lignin peroxidase activities for BSR with Wr.fungi treatment reached 748.4 U/g, 156.92 U/g, and 291.61 U/g, respectively, on the sixth day of fermentation. Concurrently, NH3-N concentration exhibited an upward trend with prolonged fermentation time. Total volatile fatty acids registered a decline, and the Acetate/Propionate ratio reached its nadir after 6 days of fermentation under the A.niger&Wr.fungi treatment. These outcomes furnish a theoretical foundation for the development of ruminant feeds treated via fungal co-culture.

Assessing genotypes of buffel grass (Cenchrus ciliaris) as an alternative to maize silage for sheep nutrition.

Nutritive value of five Cenchrus ciliaris (buffel grass) genotypes (IG96-50, IG96-96, IG96-358, IG96-401 and IG96-403) weredetermined. Their sugar contents (>70 mg/g of dry matter) and ensiling potential were evaluated using in vitro batch culture and in vivo studies. Research indicated significant differences (P < 0.05) in the dry matter, organic matter, ether extract, neutral detergent fiber, acid detergent fiber, cellulose and lignin contents of the C. ciliaris genotypes tested. Genotypes also differed (P < 0.05) in total carbohydrates, structural carbohydrates, non-structural carbohydrates and protein fractions. Genotype IG96-96 had the lowest total digestible nutrients, digestible energy and metabolizable energy contents (377.2 g/kg, 6.95 and 5.71 MJ/kg of dry matter, respectively), and net energy values for lactation, maintenance and growth. After 45 days of ensiling, C. ciliaris silages differed (P < 0.05) in dry matter, pH, and lactic acid contents, and their values ranged between 255-339, 4.06-5.17 g/kg of dry matter and 10.8-28.0 g/kg of dry matter, respectively. Maize silage had higher (P < 0.05) Organic Matter (919.5g/kg of dry matter), ether extract (20.4g/kg of dry matter) and hemi-cellulose (272.3 g/kg of dry matter) than IG96-401 and IG96-96 silages. The total carbohydrates and non-structural carbohydrates of maize silage were higher (P < 0.05), while structural carbohydrates were comparable (P < 0.05) with C. ciliaris silages. Sheep on maize silage had (P < 0.05) higher metabolizable energy, lower crude protein, and digestible crude protein intake (g/kg of dry matter) than those on C. ciliaris silage diets. Nitrogen intake and urinary-N excretion were higher (P < 0.05) on genotype IG96-96 silage diet. Overall, this study suggested that certain C. ciliaris genotypes, notably IG96-401 and IG96-96, exhibited nutritive values comparable to maize silage in sheep studies, offering a promising avenue for future exploration as potential alternatives in diversified and sustainable livestock nutrition programs.

Effects of the fermentation quality and microbial community of waxy maize mixed with fodder soybean silage.

Waxy maize (Zea mays L. sinensis Kulesh) is highly regarded for its high nutritional content and unique taste. Although the stalks and leaves contain high carbohydrate levels after ear harvesting, inadequate crude protein (CP) limits the utilization and promotion of waxy maize silage in animal husbandry. In this study, waxy maize and fodder soybeans were mixed for sowing in different proportions [1:0 (CK), 1:1 (A1), 1:2 (A2), 1:3 (A3), and 1:4 (A4)] to investigate the effects of different mixing ratios on the growth of the waxy maize, the chemical indices, fermentation quality, and the microbial community of the mixed silage after ear harvesting. The mixed planting of waxy maize and fodder soybeans in different proportions had no effect on the yield and quality of the waxy maize ears and increased the aboveground biomass after ear harvesting. After ear harvesting, the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents significantly decreased, and the CP content and relative feeding value (RFV) gradually increased in the mixed silage. The pH of the treatments was lower than 4.2 except for A4, and the lowest ammonia nitrogen (AN) concentration was observed in A3. With increasing proportions of fodder soybeans, the abundance of beneficial bacteria increased and that of harmful bacteria decreased; Firmicutes and Lactobacillus were the dominant phylum and genus, respectively, and both increased gradually. Redundancy analysis (RDA) revealed that the fermentation indices affecting the microbial community composition in the silage were inconsistent among the different mixed sowing combinations. The Mantel test showed that the composition of the microbial communities in the treatments was significantly correlated with the ADF, water-soluble carbohydrate (WSC), and propionic acid (PA) contents. Comprehensive analysis revealed that the optimal mixed sowing ratio of waxy maize to fodder soybeans was 1:3, and waxy maize and fodder soybeans silage can increase the utilization of aboveground biomass and improve the fermentation quality and feeding quality of silage by changing the microbial community. These findings lay a certain theoretical foundation for improving the utilization of waxy maize.

Determination of optimal energy system and level for growing pigs.

This study mainly evaluated the responses in growth performance of growing pigs to different energy systems and energy levels in diets. Subsequently, we compared the nutrient digestibility and digestible nutrient concentrations of each energy level diet. In experiment 1, a total of 144 growing pigs with an average initial body weight (BW) of 26.69 ± 7.39 kg were randomly allotted to six dietary treatments (four pigs/pen; six replicates/treatment) according to a 2 × 3 factorial arrangement resulting from two energy systems (metabolizable energy [ME] and net energy [NE]) and three energy levels (low [LE], recommended [C], and high energy [HE]). Pigs were fed the experimental diets for 6 weeks and were allowed free access to feed and water during the experimental period. In experiment 2, 12 growing pigs with an average initial BW of 27.0 ± 1.8 kg were randomly allotted to individual metabolism crates and fed the six diets in a replicated 6 × 6 Latin square design. The six dietary treatments were identical to those used in the growth trial. Pigs were fed their respective diets at 2.5 times the estimated energy requirement for maintenance per day, and this was divided into two equal meals provided twice per day during the experimental period. Differences in energy systems and energy levels had no significant effect on the growth performance or nutrient digestibility (except acid-hydrolyzed ether extract [AEE]) of growing pigs in the current study. However, the digestible concentrations of ether extract, AEE, and acid detergent fiber (g/kg dry matter [DM]) in diets significantly increased (p < 0.05) with increasing energy levels. Additionally, there was a tendency (p = 0.09) for an increase in the digestible crude protein content (g/kg DM) as the energy content of the diet increased. Consequently, differences in energy systems and levels did not affect the BW, average daily gain, and average daily feed intake of growing pigs. This implies that a higher variation in dietary energy levels may be required to significantly affect growth performance and nutrient digestibility when considering digestible nutrient concentrations.

Effects of Lactobacillus plantarum (L) and molasses (M) on nutrient composition, aerobic stability, and microflora of alfalfa silage in sandy grasslands.

The objective of this experiment was to investigate the effects of Lactobacillus plantarum and molasses on the nutrient composition, fermentation quality, bacterial count, aerobic stability, and microflora of alfalfa silage in sandy grasslands. The experimental treatments included control (CK), 106 CFU/g Lactobacillus plantarum (L), 5% molasses (M), and 106 CFU/g Lactobacillus plantarum + 5% molasses (LM). The nutrient composition, fermentation quality, bacterial count, aerobic stability, and microflora were determined after 14 days and 56 days of ensiling, respectively. The results showed that the addition of L, M, and LM reduced dry matter loss (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) content, and increased water-soluble carbohydrates (WSC) and ether extract (EE) content, compared to the CK group. Meanwhile, more lactic acid (LA) and accelerated fermentation were observed, causing the pH value to drop below 4.5 in the L, M, and LM groups after 56 days of ensiling. The addition of L, M, and LM promoted lactic acid bacteria (LAB), and inhibited yeast. The addition of L significantly increased the content of acetic acid (AA). In terms of microflora, the addition of L, M, and LM made Firmicutes become the dominant bacterial phylum earlier, while Lactobacillus, Weissella, and Pediococcus had a higher abundance. According to the result of Pearson's correlation, there is a very significant negative correlation between pH value and Lactobacillus (P < 0.01) and a very significant positive correlation between pH value and Lactococcus, Enterobacter, Enterococcus, and Leuconostoc (P < 0.01), which may be inhibited by Lactobacillus under the decreased pH value. The results of the prediction of microbial genes indicated that the addition of M could enhance the carbohydrate metabolism and membrane transport metabolism, which may contribute to LA production by LAB metabolism. In general, L, M and LM all improved the fermentation quality and reduced the loss of nutrients to varying degrees, but considering the fermentation quality, the overall effects of M and LM were better than L. M and LM are recommended to be used as silage additives in the process of alfalfa silage in sandy grasslands to improve the quality.

Evaluation of internal markers in digestibility estimation for sheep and goats.

The objective of this study was to compare the indirect methods of obtaining digestibility with the direct method of total fecal collection to estimate the apparent digestibility of nutrients in sheep and goats supplemented with non-protein nitrogen. Five goats and five sheep with no defined racial pattern were used, distributed in two 5 × 5 Latin squares, with split plots, considering the diets as plots and the apparent digestibility determination methodologies as subplots. The diets were composed of buffelgrass hay and the addition, via ruminal infusion, of increasing amounts of nitrogen supplementation in order to gradually raise the CP level of the basal diet in intervals of 2% points, that is, + 2, +4, + 6 and + 8%. Samples of the feeds offered, and the leftovers were collected daily during the five days of collection to determine the nutrient intake, as well as the total collection of feces to determine the apparent digestibility of the nutrients. The amount of fecal dry matter excreted was estimated by the concentration of Indigestible Acid Detergent Fiber (ADFi), Indigestible Neutral Detergent Fiber (NDFi), Indigestible Dry Matter at 244h (DMi 244h) and Indigestible Dry Matter at 264h (DMi 264h). Among the evaluated markers, DMi 264h had the lowest accuracy in estimating fecal excretion and nutrient digestibility. For the goat species, the markers ADFi and DMi 244h proved to be able to adequately predict fecal excretion and digestibility indices, while NDFi stood out for both species. Among the evaluated markers, NDFi is the one that most accurately estimates the nutrient digestibility of the diet for goats and sheep.

Effects of nitrogen fertilization rate and seeding density on the forage yield and quality of autumn‐sown triticale in an alpine grazing area of the Qinghai‐Tibetan Plateau, China

Abstract‘Gannong No. 2’ triticale (×Triticosecale Wittmack) is a cold‐resistant annual forage crop variety, which can be planted as artificial pasture to solve the problem of forage shortage in the Gannan alpine grazing area of the Qinghai‐Tibetan Plateau. However, the optimal nitrogen fertilization rate and seeding density for obtaining high yield and quality forage are still unknown. In this study, the effects of nitrogen fertilization rate and seeding density on the forage yield and quality of autumn‐sown ‘Gannong No. 2’ triticale were studied. We used a split‐plot design, with five nitrogen fertilization rates assigned to the main plots, namely 0 (A1), 120 (A2), 240 (A3), 360 (A4), and 480 kg N ha−1 (A5), and five seeding densities assigned to subplots: 506 × 104 (B1), 675 × 104 (B2), 843 × 104 (B3), 1011 × 104 (B4), and 1180 × 104 seeds ha−1 (B5). Significant differences in lodging rate, tiller number, hay yield, crude protein content, neutral detergent fibre, and relative feed value were observed at different fertilization levels. Significant differences were found in lodging rate, plant height, tiller number, hay yield, contents of neutral detergent fibre and acid detergent fibre, dry matter digestibility, and relative feed value among the seeding density treatments. The interaction of nitrogen fertilization rate and seeding density significantly affected forage yield and quality, with the A3B3 treatment having the highest comprehensive evaluation value. In alpine grazing areas of the Qinghai‐Tibetan Plateau, 240 kg N ha−1 and 843 × 104 seeds ha−1 should therefore be used for autumn‐sown triticale.

Optimum Transplanting Date for Rape Forage and Grain Yields in the Ridge Culture Place Planting System on the Yangtze River Delta

The ridge culture place planting system (RCPPS) is a promising technique for planting rapeseed that can promote the growth of rapeseed by late rice stubble, which has been widely adopted in the Yangtze River delta. To determine the optimum planting date for rape (Brassica napus L.) forage and grain yield in an intensive rice–rape rotation system, a field experiment was conducted with five transplantation dates (from 20 October to 30 November at 10 day intervals) in RCPPS. The forage/grain yield, nutrition, and growth parameters were analyzed. At podding, rape biomass yield was highest, and no significant differences were found among treatments. It was around 12.0% crude protein, 11.4% ether extract, 38.8% neutral detergent fiber, and 34.9% acid detergent fiber. In the treatments of 20 and 30 November, crude protein content increased and acid detergent fiber content decreased significantly. Compared with 20 October, the grain yield of rape transplanted in November decreased significantly by 17.2% to 22.5%. The grain yield was significantly correlated with the number of secondary branches, pods, and seeds. At the final flowering stage, rape transplanted in November had noticeably reduced leaf growth, rhizome width, and yield than 20 and 30 October. Overall, for multiple uses of rapeseed in the Yangtze River delta belt with RCPPS, it is optimal to plant in mid to late November for forage use with higher nutritional value, being coordinated with the previous rice crop, whereas late October is the appropriate planting time to obtain a higher grain yield.

Solid-state Fermentation of Wheat Bran by Aspergillus niger Strains: Effect on the Nutritional Composition and In vitro Digestibility

This study aimed to investigate the effect of Aspergillus niger on the nutritional composition and in vitro dry matter digestibility of wheat bran (WB) in solid-state fermentation. Two A. niger strains (ATCC 200345 or ATCC 52172) were used as inoculants in solid-state fermentation of WB. Wheat bran was sterilized at 121°C for 15 min and inoculated with A. niger strains at 105 spores kg-1 WB. Samples were incubated at 60°C for two days and dried at room temperature until reaching 90% dry matter. Crude protein (CP), ether extract (EE), ash, crude fiber (CF), hemicellulose, neutral detergent fiber (NDF) and acid detergent fiber (ADF) content and in vitro dry matter digestibility of WB and fermented WB were determined. The CP and ash levels were increased (P

Effects of tillage and maturity stage on the yield, nutritive composition, and silage fermentation quality of whole-crop wheat.

Whole-crop wheat (Triticum aestivum, WCW) has a high nutritional value and digestibility. No-tillage (NT) can reduces energy and labor inputs in the agricultural production process, thus decreasing production costs. There are many studies on planting techniques of WCW at present, few being on no-tillage planting. This study aimed to compare the effects of different tillage methods and maturity stages on the yield, nutritive value, and silage fermentation quality of WCW. The experiment included two tillage methods (NT; conventional tillage, CT), two maturity stages (flowering stage; milk stage), and three years (2016-2017; 2017-2018; 2018-2019). Years had a strong influence on the yield and nutritional composition of WCW. This was mainly related to the amount of rainfall, as it affects the seedling emergence rate of wheat. Although tillage methods showed no significant effects on the yield, plant height, and stem number per plant of WCW (P > 0.05), compared to CT, the dry matter (DM) and crude protein (CP) yields of NT decreased by 0.74 t/ha and 0.13 t/ha. Tillage methods showed no significant effects on the nutritive composition of WCW (P > 0.05). The WCW at the milk stage had greater DM (5.25 t/ha) and CP (0.60 t/ha) yields than that at the flowering stage (3.19 t/ha and 0.39 t/ha) (P< 0.05). The acid detergent fiber concentration of WCW decreased by 34.5% from the flowering to the milk stage, whereas water-soluble carbohydrates concentration increased by 50.6%. The CP concentration at the milk stage was lower than that at the flowering stage (P< 0.05). The lactic acid concentration of NT (17.1 g/kg DM) silage was lower than that of CT (26.6 g/kg DM) silage (P< 0.05). The WCW silage at the milk stage had a lower NH3-N concentration (125 g/kg TN) than that at the flowering stage (169 g/kg TN) (P< 0.05). Wheat sown by NT and CT was of similar yield and nutritional value, irrespective of harvest stages. WCW harvested at the milk stage had greater yield and better nutritional composition and silage fermentation quality than that at the flowering stage. Based upon the results of the membership function analysis, no-tillage sowing of wheat was feasible and harvesting at milk stage was recommended.

Enhancing biomass conservation and enzymatic hydrolysis of sweet sorghum bagasse by combining pretreatment with ensiling and NaOH.

Lignocellulosic pretreatment is an important stage in biomass utilization, which usually requires high input. In this study, a low-cost method using combined ensiling and NaOH was developed for lignocellulosic pretreatment. Sweet sorghum bagasse (SSB) was ensiled for 21 days and then treated with diluted NaOH (0%, 1%, and 2%) for fermentation. The results showed that the application of Lactobacillus plantarum (L) reduced fermentation losses of the silages, mainly low water-soluble carbohydrate (WSC) and ammonia nitrogen loss. Meanwhile, the application of Lactobacillus plantarum and ensiling enzyme (LE) promoted lignocellulosic degradation, as evidenced by low neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (ADL), and hemicellulosic (HC) contents. The dominant bacterial genera were Lactobacillus, uncultured_bacterium_f_Enterobacteriaceae, and Pantoea after silage, which corresponded to the higher lactic acid and acetic contents and lower pH. The reducing sugar yields of SSB increased after combined pretreatment of silage and NaOH and were further enhanced by the 2% NaOH application, as evidenced by the high reducing sugar yield and microstructure damage, especially in the L-2% NaOH group and the LE-2% NaOH group, in which the reducing sugar yields were 87.99 and 94.45%, respectively, compared with those of the no additive control (CK)-0 NaOH group. Therefore, this study provides an effective method for SSB pretreatment to enhance biomass conservation.

Effects of Cellulase and Xylanase on Fermentation Characteristics, Chemical Composition and Bacterial Community of the Mixed Silage of King Grass and Rice Straw.

This study was to investigate the effects of cellulase and xylanase on fermentation characteristics, nutrient composition and the bacterial community of the mixed silage of king grass and rice straw. Lab-scale bag silage was produced and seven groups were studied: blank control (CK); added 1%, 2% cellulase (CE1, CE2); added 1%, 2% xylanase (XY1, XY2); and added 0.5% cellulase +0.5% xylanase, 1% cellulase +1% xylanase (CX1, CX2). The results showed that the application of additives in six treated groups exerted a positive effect on lactic acid (LA) content and their pH values decreased significantly (p < 0.05). The addition of cellulase and xylanase decreased (p < 0.05) the content of neutral detergent fiber (NDF) and acid detergent fiber (ADF) significantly and increased (p < 0.01) the crude protein (CP) and water-soluble carbohydrate (WSC) content. Filter paper enzyme activity (FPA) declined and xylanase activity (XA) intensified (p < 0.05) as ensiling was prolonged, where most of the enzymatic treatments (especially XY2, CX2) resulted in increased enzyme activities. Moreover, the addition of cellulase and xylanase reduced the abundance of harmful bacteria such as Acinetobacter and Klebsiella and increased the abundance of lactic acid bacteria such as Lacticaseseibacillus, Lactiplantibacillus. In conclusion, the addition of cellulase and xylanase would improve fermentation quality and nutrient preservation via altering the bacterial community, with 1% cellulase or complex enzyme best.

Effect of Growth Stage on Nutrition, Fermentation Quality, and Microbial Community of Semidry Silage from Forage Soybean.

Soybean (Glycine max (Linn.) Merr.) is highly suitable as animal feed. The silage quality and microbial characteristics of soybean silage are still unclear. Forage soybean (HN389), at six different growth stages (R2-R7), were used as experimental materials to investigate the changes in fermentation, nutritional quality, and microbial characteristics of semidry silage after 0, 7, 14, 30, and 45 d. As the growth period extended, the content of crude protein (CP) and crude fat (EE) gradually increased, while the neutral detergent fiber (NDF) and the acid detergent fiber (ADF) content decreased. The pH value also decreased gradually with fermentation time, accompanied by increases in the proportion of ammonia-N and the content of lactic acid (LA) and acetic acid (AA). In addition, competitive inhibition was observed in the microbial fermentation. With the process of ensiling, Lactobacillus became the dominant bacterial species. The results indicate that the most active stage of fermentation during ensiling occurred within the first 7 days, the fermentation and nutritional quality of the soybean forage were improved, and the optimal mowing stage was the grain stage. Comparison of the microbial abundance showed that all microorganisms entered a stable stage at 30 days of silage. After storage, the dominant bacteria were Lactobacillus, Enterobacter, and Pantoea.

Heat-resistant lactic acid bacteria inoculants modulated the bacterial microbiota and fermentation quality of whole plant maize silage after long-term storage in the subtropical area

In tropical or subtropical areas, high temperatures and prolonged storage time usually result in poor fermentation quality, poor aerobic stability and dry matter loss of silages. This study explored the effect of heat-resistant Lactobacillus buchneri TSy1–3 (LB), Lactobacillus rhamnosus BDy3–10 (LR), and their combination (M) on the nutritional characteristics, fermentation parameters and microbiota of whole plant maize silage during long-duration ensiling in the subtropical area. The results showed that long-term ensiling naturally led to a decrease in water-soluble carbohydrate, neutral detergent fiber and acid detergent fiber concentrations. In contrast to the control treatment, LB, LR and M reduced the coliform bacteria population and the nutrient loss, while increased lactic acid bacteria population and acetic acid and propionic acid concentrations after 180 d of fermentation. Moreover, they helped to increase Lactobacillus abundance and made it still dominate the bacterial community during long-term storage. The negative/positive ratio was higher in the LR and LB treatments when compared with the control treatment, suggesting that LR and LB increased the stability of the bacterial community networks. The heat-resistant inoculants rapidly produced lactic acid to modulate the bacterial community composition during 60 d of ensiling, while generated more acetic acid and propionic acid to alter the microflora during 180 d of ensiling. This may be caused by predicted functions indicating that metabolism pathways were modulated by different inoculations and storage times. Overall, heat-resistant lactic acid bacteria improved the nutritional and fermentation quality of ensiled forage and regulated the bacterial community during long-term storage in the subtropical region.