Search Results (50)

Oat (Avena sativa L.) silage fermentation often fails due to insufficient lactic acid bacteria (LAB) and low water-soluble carbohydrate content. We investigated the effects of Compound Radix Pulsatillae (CRP; 40 g/kg FM) alone or combined with a commercial LAB inoculant (containing L. plantarum, L. buchneri, and Enterococcus faecium, CRP_LA) on oat silage after 60 days. Compared to control (CK), both CRP and CRP_LA increased dry matter and water-soluble carbohydrate retention while reducing fiber components and ammonia nitrogen (p < 0.05). CRP_LA exhibited superior fermentation quality (lowest pH 4.82, highest lactic acid 47.83 g/kg DM). Using 16S rRNA sequencing and UPLC-MS/MS metabolomics integrated with weighted gene co-expression network analysis (WGCNA), we identified a brown module strongly associated with CRP_LA treatment. Six hub metabolites, belonging to flavonoids, terpenoids, alkaloids, phenolic acids, and nucleotide derivatives, were significantly elevated in CRP_LA silage and showed strong correlations with Lactobacillus abundance and fermentation quality parameters. Correlation-based network analysis revealed that these hub metabolites positively correlated with Lactobacillus abundance, lactic acid, and water-soluble carbohydrate retention, while negatively correlating with spoilage microorganisms (Enterobacter, Acinetobacter, Leuconostoc) and ammonia nitrogen. This multi-omics study provides a metabolite-centric molecular map of the silage microecosystem reshaped by CRP and LAB co-fermentation. The identified hub metabolites—with predicted antimicrobial, antioxidant, and plant-protective functions—represent potential quality markers for functional silage additive development. Mechanistic validation via targeted metabolite supplementation or pathway-specific gene expression analysis is warranted in future studies. Full article

Freeze–thaw cycles on the Qinghai–Tibetan Plateau inhibit microbial activity and challenge silage preservation. This paper aimed to elucidate how an indigenous, freeze–thaw-resistant Lactobacillus plantarum strain (LP160) improves oat silage quality under such stress. Oats were ensiled for 60 days under constant 20 °C (t) or freeze–thaw cycles (12 h at 20 °C/−5 °C; s) with or without LP160 inoculation. Samples after ensiling and 5-day aerobic exposure were analyzed for fermentation parameters, nutrients, microbiome, and non-targeted metabolomics using liquid chromatography–tandem mass spectrometry (LC-MS/MS). LP160 inoculation improved silage quality, as shown by the lower pH, ammoniacal nitrogen, neutral detergent fiber, acid detergent fiber contents as well as the greater amount of lactic acid. Key findings demonstrated that LP160 inoculation significantly enhanced Lactobacillus dominance, effectively curbed the growth of detrimental bacteria like Mucor, and regulated the microbial structure. During the aerobic exposure phase, the microbial community structures and successions varied under different temperature treatments. When inoculated under freeze–thaw conditions, the genus Bacillus increased, while Paenibacillus was not impeded. A total of 943 metabolites were identified, predominantly comprising amino acids, fatty acids, and the like. The expressions of metabolites with antioxidant and antibacterial properties were upregulated with LP160 inoculation. This led to the inhibition of protein hydrolysis and a reduction in ammonia–nitrogen production. The results of correlation analysis indicated that inoculating LP160 suppressed the proliferation of Mucor and enhanced the abundance of Torulaspora; meanwhile, the expression of L-palmitoylcarnitine involved in the fatty acid degradation pathway and fatty acid metabolism pathway was inhibited along with the generation of ammonia–nitrogen. Consequently, the degradation of fatty acids and proteins was restrained. The results of this paper provided new insights into the silage under freeze–thaw conditions. Full article

Growth stage alters substrate availability and moisture in oats, potentially driving microbial succession and metabolite formation during ensiling. Oats were harvested at flowering (FS), milk ripening (MS) and wax ripening (DS) stages and vacuum-bag ensiled for 120 d (n = 4 per stage). We measured chemical composition and fermentation products, enumerated key microbes, profiled bacterial communities by 16S rRNA gene amplicon sequencing, and characterised metabolites by untargeted LC–MS. With advancing growth stage, dry matter (DM), neutral detergent fibre (NDF) and acid detergent fibre (ADF) increased, whereas crude protein (CP) decreased. MS silage had the lowest pH (4.63) and the highest CP, whereas FS showed higher lactic acid, but the butyric acid (BA) and NH₃-N/TN were also significantly higher than those at MS and DS (p < 0.001). Community composition shifted from Enterobacter (FS) toward Lactobacillus enrichment (DS), accompanied by stage-specific metabolite signatures (biogenic amines and indoleacetic acid at FS; betaine and purine metabolites at MS; reduced amines and more amino-acid derivatives at DS). Overall, under the conditions of this study, considering fermentation stability, nutrient preservation, microbial diversity, and metabolic pathways, the best balance was achieved during MS. Full article

This study explored the patterns and mechanisms influencing changes in silage quality, mycotoxin accumulation, and microbial community structure in oat silage after lodging. Upright oat forage (control, CK), lodging oat forage (upper layer (UL), lower layer (LL), and mixed layers (MLs) were harvested at 0, 7, 25, and 45 days after lodging and ensiled for 60 days. The results showed that the dry matter (DM) and water-soluble carbohydrate (WSC) content decreased significantly (p < 0.05), whereas crude protein (CP) and fiber content increased significantly compared to upright oats (p < 0.05). The WSC and CP content in silage decreased with increasing lodging duration. The fiber content increased in late harvest after lodging. The risk of mycotoxin infection increased after lodging, with aflatoxin levels exceeding EU limits. The mycotoxins in UL silage were the lowest when lodging lasted for seven days. Lodging oat silage was dominated by Lactobacillus, and the Pseudomonas in the lodging group was less than 4%. The fungi in lodging oat silage was lower, and the UL (upper layer) treatment was the lowest when lodging for 7 days. Overall, the transfer of microorganisms, especially Plectosphaerella, Fusarium, Alternaria, Cladosporium, and Botryotrichum, from soil to silage following oat collapse is of interest. The results suggest the soil–plant microbial interactions and their effects on silage fermentation and mycotoxins in lodging oats. Full article

Oat is a forage with high protein value (10–14% DM) and good palatability, and is considered one of the main feed sources for ruminants. In this experiment, Lacticaseibacillus rhamnosus and Lentilactobacillus buchneri were selected as silage additives to investigate the fermentation quality, nutrient composition, microbial community and relationship between fermentation products and bacterial community of small-bale oat silage after ensiling. The experiment was set up with three treatment groups and three replications in each group, which were the control (C) group, L. rhamnosus (LR) group and L. buchneri (LB) group, and oat silages were subjected to 10-day and 30-day storage periods. The results show that both LR and LB additions significantly increased water-soluble carbohydrate, crude protein, lactic acid, propionic acid and acetic acid contents, and decreased pH, butyric acid, acid detergent fiber, neutral detergent fiber, and ammonia nitrogen contents and yeast and enterobacteria numbers in small-bale oat silage, compared with the C group. The highest content of acetic acid and the lowest numbers of enterobacteria and yeast were found in the LB group after 30 days of fermentation. Lentilactobacillus and Lacticaseibacillus were the dominant genera in the LB and LR groups, regardless of fermentation time. Lentilactobacillus and Lacticaseibacillus were positively correlated with a correlation value of 0.9, but both were negatively correlated with Bacillus. Lentilactobacillus and Lacticaseibacillus were positively correlated with acetic and lactic acids, while pH and butyric acid were positively correlated with Bacillus. This experiment revealed that the addition of homofermentative and heterofermentative lactic acid bacteria enhanced the relative abundance of Lentilactobacillus and Lacticaseibacillus, reduced harmful microbes, and improved fermentation quality of small-bale oat silage. Full article

Ensiling forage under low-temperature conditions often leads to poor fermentation and nutrient losses. This study evaluated the effects of a cold-tolerant Pediococcus pentosaceus OL77 strain on oat silage. Silages were prepared with or without Pediococcus pentosaceus inoculation (1 × 10⁵ cfu/g FM). After 90 days, OL77-treated silage showed markedly higher lactic acid (45.83 vs. 30.51 g/kg DM), lower pH (3.88 vs. 4.443), and better preservation of WSC (64.68 vs. 47.60 g/kg DM) and crude protein (89.26 vs. 65.52 g/kg DM) than the control. Microbial analysis revealed accelerated colonization by Pediococcus, reduced bacterial diversity, and faster stabilization of the fermentation process. Functional predictions indicated enhanced carbohydrate and energy metabolism. These findings demonstrate that OL77 can effectively improve fermentation quality and nutrient preservation of oat silage under low-temperature conditions, offering a practical inoculant option for cold regions. Full article

The purpose of this study was to explore the effects of co-ensiling Caragana korshinskii with different proportions of oat grass on silage fermentation quality, chemical composition, in situ rumen degradability and in vitro rumen fermentation characteristics. C. korshinskii and oat grass were mixed at different ratios of 100:00, 90:1, 80:2, 70:30, 60:40 and 50:50. Each ratio of mixture was ensiled for 7, 14, 30, 45 and 60 days at room temperature (25 °C), with 30 bags per ratio, for a total of 180 bags. We further investigated the dynamic profiles of the bacterial community during ensiling and in vitro rumen fermentation. The results showed that co-ensiling C. korshinskii and oat grass decreased the pH values and increased the content of lactic acid and acetic acid compared with ensiling C. korshinskii alone. C. korshinskii ensiled with oat grass at a ratio of 70:30 (70% C. korshinskii) showed the best fermentation quality, which was related to higher relative abundance of Lactobacillus and Weissella. The silage with the ratio of 70:30 (70% C. korshinskii) showed higher dry matter digestibility and the more production of gas and total volatile fatty acids, compared with fresh C. korshinskii. In conclusion, C. korshinskii co-ensiled with oat grass at a ratio of 70:30 could enhance the fermentation quality and digestibility of C. korshinskii. Full article

Silage is an effective method for alleviating winter feed shortages, but the mechanisms by which the silage microorganisms and metabolites respond to a mixture of oats and vetch at low temperatures remain unclear. In this study, the quality, microorganisms, and metabolites of oats mixed with vetch as a silage material, as well as after 90 days of silage, were analyzed. The traditional view holds that a decrease in microorganism diversity during silage indicates successful fermentation. However, in the present study, microorganism diversity was found to increase after silage under alpine and low-temperature conditions, with a significant rise in the abundance of microorganisms such as Levilactobacillus and Kazachstania. This phenomenon may be explained by the inhibition of rapid lactic acid bacteria proliferation by low temperatures, which allows for the survival of other cold-tolerant microorganisms and their involvement in metabolism. These microorganisms significantly increased the levels of metabolites such as l-methionine, l-glutamine, arachidonic acid, and linolenic acid in the mixed feeds, while simultaneously significantly decreasing the levels of metabolites such as l-leucine, l-arginine, l-asparagine, and glyceric acid. These metabolites possess antioxidant and anti-inflammatory properties that enhance the nutritional value of the feed and indirectly improve the immunity and performance of ruminants. This study comprehensively revealed the complex network of interactions between microorganisms and metabolites in the mixed forage of oats and vetch in alpine pastures and elucidated the regulatory mechanism of silage under low temperatures. The subsequent development of microorganism preparations for the targeted regulation of silage quality provides a theoretical foundation for producing high-quality silage in alpine pastures. Full article

The production of artificial planted forage is important for the development of animal husbandry in the Qinghai–-Tibet Plateau, and oat forage is one of the main artificial planted forages in the area. However, the suitable oat varieties for harvesting and preparing silage feed in this region are still unclear. To investigate suitable oat forage varieties for silage production and the potential feeding value of different oat forage varieties, 16 oat forage varieties planted in Qinghai Province were selected in this experiment. These oat forages were subjected to two treatments: a group with no inoculants (CK) and a group with self-selected lactic acid bacteria (LAB) inoculants (IN). After 90 days of ensiling, silage quality and in vitro digestibility of the 16 oat forage varieties were determined. The results showed that all oat forage varieties ferment well after ensiling (pH < 4), the CK group had a silage pH range of 3.62–3.95, and the IN group had a silage pH range of 3.68–3.83. Tianyan No.1, Qingtian No.2, and Tianyan No.3 were in the top three in RFV and RFQ rankings in the CK group, while Qinghai 444, Tianyan No.1, and Tianyan No.3 were in the lead in GI rankings. Tianyan No.1, Qingtian No.2, and Everleaf 126 were in the lead in RFV and RFQ rankings in the IN group, while Qinghai 444, Titan, and Tianyan No.1 were in the top three in GI rankings. The dry matter digestibility and 72 h cumulative gas production of the IN group were higher than that of the CK group (p < 0.05). Based on principal component analysis and membership function comprehensive evaluation, Tianyan No.1, Qinghai 444, and Tianyan No.3 ranked the top three, demonstrating that these three oat forage varieties are suitable for silage processing in the Qinghai–Tibet Plateau region. Full article

Maize (Zea mays L.) is the world’s most productive cereal crop, yet it is threatened by several diseases. Among them, Fusarium stalk rot (FSR) causes an average global yield loss of 4.5%. The mycotoxins deoxynivalenol, zearalenone, fumonisins, and moniliformin persist in grain and silage after harvest and pose a risk to human and animal health. This review describes the lifestyle of the fungal pathogens that cause FSR, studies how to optimize resistance evaluation, identifies quantitative trait loci (QTLs) and candidate genes (CGs), and, finally, considers the methods for selecting FSR resistance, especially through genomic selection. To screen maize genotypes for FSR resistance, several artificial inoculation methods have been employed in most studies, including toothpick insertion, ball-bearing pellets, root infection, and the oat kernel method. However, these methods have several limitations in effectively inducing FSR disease infection. Needle injection of inoculum into the stem is recommended, especially when combined with a quantitative or percentage scale because it effectively phenotypes maize populations for FSR resistance. Nine studies with larger populations (≥150 progenies) investigated the genetic architecture of FSR resistance. The inheritance is clearly quantitative. Four major QTLs and several minor QTLs are reported to confer resistance to FSR pathogens, and a few CGs have been identified. Genomic selection is recommended as an effective method for developing routinely FSR-resistant maize, but only two studies have explored this area. An omics analysis (proteomics, transcriptomics, and metabolomics) of the expression of candidate genes should validate their role in FSR resistance, and their use might accelerate selection. Full article

The objective of this experiment was to determine whether compound microbial inoculants could enhance the fermentation of oat and common vetch silage that were stored in the Northwest Sichuan Plateau for 60 days under extremely low temperatures. Oat and common vetch harvested from single and mixed artificially planted grassland of oat and common vetch were chopped into 2–3 cm (oat, S1; common vetch, S2; oat–common vetch = 2:1, S3), then sterile water (T1), Zhuang Lemei IV silage additive (T2), and Fu Zhengxing silage additive (T3) were added to the feed and ensiled at the local outdoor environment for 60 days. Data were analyzed as a 3 × 3 factorial arrangement of treatments with the main effects of the materials, additives, and their interaction. Interactions between the materials and additives significantly affected the fermentation quality and the content of DM, WSC, and NDF and the number of yeasts in forages. Treatments with S3 have significantly higher contents of lactic acid, acetic acid, and lactic acid bacteria in the feed than those in the S1 and S2 treatments, while the contents of AN/TN and propionic acid were significantly lower compared with the S1 and S2 treatments (p < 0.05). Concentrations of lactic acid, acetic acid, and propionic acid were significantly increased and the content of neutral detergent fiber in the T2-treated silage decreased compared with the T1 treatment (p < 0.05). The T3 treatment significantly reduced the number of yeasts in the silage but the compound lactic acid bacteria additive treatment (T1, T2) significantly decreased the butyric acid content and pH of the feed and increased the acid detergent fiber content and the number of lactic acid bacteria in the feed compared with the T1 treatment. Among them, the butyric acid content of the T3 treatment decreased by 63.64–86.05%, while that of the T2 treatment decreased by 36.36–83.33% (p < 0.05). The comprehensive analysis of the membership function revealed that the silage quality was the best after the S3T2 treatment, so the implementation of the S3T2 combination in the Northwest Sichuan Plateau can provide guarantees for the production of local high-quality forage grass and alleviate the shortage of forage grass. Full article

This study was carried out in Haiyan County, Qinghai Province. The aim was to explore the impacts of a mixed cropping of oats and peas sown in a corral with the addition of lactic acid bacteria (LAB) including Lactobacillus plantarum, Lactobacillus buchneri, and Pediococcus pentosaceus on silage quality, so as to alleviate the shortage of winter forages. A two-factor experimental design was adopted. For the treatments with and without LAB addition, the ratios of oat to pea in the plots were set as 1:0, 2:1, 1:1, 1:2, and 0:1, respectively. Subsequently, the materials were subjected to the silage process at 19 °C for 45 days. Silage samples were collected to determine their sensory quality, nutritional quality, and fermentation quality in order to evaluate the fermentation effect. The results showed that mixed cropping could improve forage quality. Without the addition of LAB, the soluble sugar content of the mixture of oats and peas in a 2:1 ratio increased significantly by 21.9% compared with that of the pea monoculture (p < 0.05), and the crude protein content of the mixture of oats and peas in a 1:2 ratio increased by 31.6% compared with that of the oat monoculture (p < 0.05). Meanwhile, the contents of acid and neutral detergent fibers decreased significantly (p < 0.05) with the increase in pea radios. After the addition of LAB, different results were obtained due to the fermentation of lactic acid bacteria during the silage process. The pH value decreased, the lactic acid content increased significantly, and the ratio of ammonia nitrogen to total nitrogen decreased significantly. Based on comprehensive analysis, an appropriate mixed cropping ratio combined with LAB addition can improve silage quality. Among them, the mixture of oats and peas in a 1:1 ratio with LAB addition for silage had the highest silage score, indicating good silage and feed quality. I While with or without LAB addition, the ratio of 1:2 is the best, followed by the ratio of 1:1. Full article

The primary objective of this study was to explore the effects of biological additives, including Streptococcus bovis (SB), Bacillus subtilis (BS), xylanase (XT), and their combined treatments, including SB + BS (SBBS), SB + XT (SBXT), and BS + XT (BSXT), on the chemical composition, fermentation characteristics, and microbial community of high-moisture oat silage. Compared with the CK group (control group without additives), SB and SBBS treatments increased the lactic acid content (p < 0.05) and reduced the contents of acetic acid, propionic acid, butyric acid, and ammonia nitrogen in silage (p < 0.05). XT, SBXT, and BSXT treatments decreased the neutral detergent fiber and acid detergent fiber contents (p < 0.05), increasing the water-soluble carbohydrate content (p < 0.05). The SB, SBBS, and SBXT treatments increased the abundance of Lactiplantibacillus (p < 0.05) and significantly decreased microbial richness with diversity (p < 0.05), improving the microbial community structure in silage. The addition of XT increased the relative abundance of Clostridium and Enterobacteriaceae, but its combination with SB and BS increased the abundance of Lactiplantibacillus and inhibited the development of undesirable bacteria. Moreover, different additives changed the metabolism of carbohydrates, amino acids, energy, cofactors and vitamins of bacterial communities during ensiling. In summary, the addition of SB and SBBS was more conducive to improving the fermentation characteristics of oat, while XT, SBXT, and BSXT performed better in degrading lignocellulose in plants. Full article

Planting oat forage in fallow fields during winter and producing total mixed ration (TMR) silage can effectively address issues of land wastage and forage shortages while maintaining forage quality. This study used oats and common vetch grown in winter fields in southern China as base materials, with additives including corn flour, soybean meal, corn lees, cottonseed meal, and premixes to formulate mixed feeds with roughage-to-concentrate ratios of 75:25, 70:30, and 65:35 on a dry matter basis. TMR silage was inoculated with a customized mixed lactic acid bacteria (LAB) additive composed of Lactobacillus plantarum 160 (patent number ZL202210218695.5), Lactobacillus pentosus 260 (patent number ZL202210204293), and Lactobacillus buchneri 225 (patent number ZL202210204293), at a ratio of 2:1:1, with addition rates of 4 × 10⁶, 2 × 10⁶, and 2 × 10⁶ cfu/g, respectively (IN), while sterile distilled water served as the control (CK). After a 60-day fermentation, the cornell net carbohydrate protein system (CNCPS) and in vitro digestion analysis were used to assess the effects of different roughage-to-concentrate ratios on the carbohydrate and protein components and ruminal degradation rate of fermented TMR (FTMR) silage, as well as to evaluate the impact of mixed LAB inoculation on FTMR nutritional quality, fermentation quality, and aerobic stability. The results indicated the following: (1) Regardless of the LAB addition, dry matter (DM), ether extract (EE), crude protein (CP), and Ash contents significantly decreased (p < 0.05) as the concentrate level decreased. In the IN group, as the concentrate level decreased, the water-soluble carbohydrate (WSC) content significantly increased (p < 0.05), the pH significantly decreased (p < 0.05), and the NH₃-N/TN significantly decreased (p < 0.05), with LAB counts significantly higher at a 65:35 roughage-to-concentrate ratio than in the other two groups. In the CK group, no significant changes (p > 0.05) were observed in the WSC content, pH, or LAB counts. (2) CNCPS analysis showed that in the IN group, the carbohydrate (CHO) content at a 75:25 roughage-to-concentrate ratio was significantly higher than in the other two groups (p < 0.05), while the non-utilizable carbohydrate (CC) content was significantly lower (p < 0.05). As the concentrate levels decreased, the non-protein nitrogen (PA) and moderately degradable true protein (PB2) content significantly increased (p < 0.05), whereas the rapidly degradable true protein (PB1) and slowly degradable true protein (PB3) content significantly decreased (p < 0.05). In the CK group, the CHO, PA, PB2, and PC content significantly increased (p < 0.05) as concentrate levels decreased, while the PB1 and PB3 content significantly decreased (p < 0.05). (3) In vitro digestibility characteristics indicated that gas production (GP) in the IN group was significantly lower than in the CK group (p < 0.05), with crude protein degradability increasing as concentrate levels decreased, regardless of the LAB addition. (4) At a 65:35 roughage-to-concentrate ratio, aerobic stability in the IN group was significantly higher than in the CK group (p < 0.05). In conclusion, higher concentrate ratios in total mixed rations (TMRs) with varying roughage-to-concentrate proportions improve the nutritional quality and promote the ruminal degradation of the FTMR. LAB inoculant addition could be an effective approach for addressing FTMR feed challenges. Full article

This study examined the effects of different forage sources on the ruminal bacteriome, growth performance, and carcass characteristics of Hanwoo steers during the fattening stage. In Korea, where high-concentrate feeding is common, selecting suitable forage is crucial for sustainable beef production. Fifteen 23-month-old Hanwoo steers, weighing an average of 679.27 ± 43.60 kg, were fed the following five different forage sources: oat hay (OAT), rye silage (RYE), Italian ryegrass (IRS), barley forage (BAR), and rice straw silage (RSS), alongside 1.5 kg of dry matter concentrate daily for five months. Carcass traits were evaluated post-slaughter, and rumen fluid samples were analyzed using full-length 16S rRNA gene sequencing to determine the bacteriome composition. The forage source significantly affected the alpha-diversity indices and bacteriome biomarkers linked to the feed efficiency and ruminal fermentation. Differences in the backfat thickness and meat yield index were noted, with alpha-diversity indices correlating with carcass traits. The phylum Planctomycetota, especially the family Thermoguttaceae, was linked to nitrogen fixation in high-protein diets like IRS, while the genus Limimorpha emerged as a biomarker for the meat yield. These findings highlight the importance of forage selection during late fattening to optimize beef production, considering diet and bacteriome shifts. Full article