Effects of different temperature and density on quality and microbial population of wilted alfalfa silage.

In this experiment, alfalfa silage with different packing densities (500 kg/m3、600 kg/m3 and 700 kg/m3) was prepared under the conditions of outdoor high temperature and indoor room temperature, respectively. At the same time, the same lactobacillus additive was used for fermentation in each density treatment group. The chemical composition, fermentation quality and microbial community of alfalfa silage were analyzed. The results showed that the contents of dry matter (DM) and water-soluble carbohydrate (WSC) decreased with the increase of density during fermentation at high temperature. At the same time, when the density is 600 kg/m³, CP (crude protein) content is the highest, ADF (acid detergent fiber) content is the lowest. The contents and pH values of neutral detergent fiber (NDF), lactic acid (LA) and lactic acid bacteria (LAB) were significantly affected by temperature (p < 0.05). Density had significant effects on DM, NDF, WSC and LA contents (p < 0.05). The interaction between temperature and density had significant effects on the content of ADF and LAB (p < 0.05). At the same time, the abundance of Lactiplantibacillus plantarum in high temperature fermented silage was lower than that in normal temperature fermented feed. The number of Lactiplantibacillus plantarum in room temperature treatment group decreased with the increase of density. In summary, this study clarified the effects of different temperature and density on alfalfa fermentation quality and microbial community, and clarified that the density should be reasonably controlled within 600 kg/m³ during alfalfa silage, providing theoretical support for production practice.

Effects of temperature and lactic acid Bacteria additives on the quality and microbial community of wilted alfalfa silage.

This study investigated the influence of different temperatures (35℃ High temperature and average indoor ambient temperature of 25℃) and lactic acid bacterial additives (Lactiplantibacillus plantarym, Lentilactobacillus buchneri, or a combination of Lactiplantibacillus plantarym and Lentilactobacillus buchneri) on the chemical composition, fermentation quality, and microbial community of alfalfa silage feed. After a 60-day ensiling period, a significant interaction between temperature and additives was observed, affecting the dry matter (DM), crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF) of the silage feed (p < 0.05). Temperature had a highly significant impact on the pH value of the silage feed (p < 0.0001). However, the effect of temperature on lactic acid, acetic acid, propionic acid, and butyric acid was not significant (p > 0.05), while the inoculation of additives had a significant effect on lactic acid, acetic acid, and butyric acid (p > 0.05). As for the dynamic changes of microbial community after silage, the addition of three kinds of bacteria increased the abundance of lactobacillus. Among all treatment groups, the treatment group using complex bacteria had the best fermentation effect, indicating that the effect of complex lactic acid bacteria was better than that of single bacteria in high temperature fermentation. In summary, this study explained the effects of different temperatures and lactic acid bacterial additives on alfalfa fermentation quality and microbial community, and improved our understanding of the mechanism of alfalfa related silage at high temperatures.

Biofermentation of aquatic plants: Potential novel feed ingredients for dairy cattle production.

The study assessed the impacts of aquatic plant silages on feeding efficiency and dairy cattle health as an alternative to conventional corn silage under high altitude conditions. Mid-lactation Holstein cows were assigned to treatment groups according to a randomized complete block design of parity, previous 105-d milk yield, and body weight. Cows (n = 8 per group) were fed with aquatic plant silage inoculated with Bacillus subtilis (BS), Yeast (YS), or conventional corn silage without inoculants (control) in addition to [standard grain feed] for 75 consecutive days. BS and YS had higher protein contents than control silage (111.20 ± 7.68, 112.10 ± 6.83 vs 76.94 ± 3.48 g/kg DM), while feeding efficiency was comparable between treatments (1.07, 0.99, and 0.90, respectively). In addition, the addition of aquatic plant silage in ruminant diets enhanced immunity and antioxidant capacity when compared with control group. Metagenomic analysis showed similar composition in rumen microbiota between YS and control groups, with higher enrichment for energy and nitrogen utilization pathways in YS-treated cows. This study highlights the use of aquatic plant silage as an alternative feed for dairy cattle with higher protein than corn silage. Our results suggest YS or BS could potentially boost immune and antioxidant functions, improving adaptation to high-altitudes and reducing demand for high input corn production on the Qinghai-Tibetan Plateau.

Inoculum microbial mass is negatively related to microbial yield and positively to methane yield in vitro.

Ruminal microbes catabolise feed carbohydrates mainly into SCFA, methane (CH4), and carbon dioxide (CO2), with predictable relationships between fermentation end products and net microbial increase. We used a closed in vitro batch culture system, incubating grass and maize silages, and measured total gas production at 8 and 24 h, as well as the truly degraded substrate, the net production of SCFA, CH4, and microbial biomass at 24 h, and investigated the impact of silage type and inoculum microbial mass on fermentation direction. Net microbial yield was negatively correlated with total gas at 8 h (P < 0•001), but not at 24 h (P = 0•052), and negatively correlated with CH4 production (P < 0•001). Higher initial inoculum microbial mass was related to a lower net microbial yield (P < 0•001) but a higher CH4 production (P < 0•001). A significant difference between grass silage and maize silage was detected within the context of these relationships (P < 0•050). The metabolic hydrogen (2H) recovery was 102.8 ± 12.3 % for grass silages and 118.8 ± 13.3% for maize silages. Overall, grass silages favoured more substrate conversion to microbial biomass and less to fermentation end products than maize silage. Lower inoculum microbial mass facilitated more microbial growth and, because of the 2H sink by microbial synthesis, decreased CH4 production.

Heterofermentative Lentilactobacillus buchneri and low dry matter reduce high-risk antibiotic resistance genes in corn silage by regulating pathogens and mobile genetic element.

The study of antibiotic resistance in the silage microbiome has attracted initial attention. However, the influences of lactic acid bacteria inoculants and dry matter (DM) content on antibiotic resistance genes (ARGs) reduction in whole-plant corn silage remain poorly studied. This study accessed the ARGs' risk and transmission mechanism in whole-plant corn silage with different DM levels and treated with Lactiplantibacillus plantarum or Lentilactobacillus buchneri. The macrolide and tetracycline were the main ARGs in corn silage. The dominant species (Lent. buchneri and Lactobacillus acetotolerans) were the main ARGs carriers in whole-plant corn silage. The application of Lent. buchneri increased total ARGs abundance regardless of corn DM. Whole-plant corn silage with 30 % DM reduced the abundances of integrase and plasmid compared with 40 % DM. The correlation and structural equation model analysis demonstrated that bacterial community succession, resulting from changes in DM content, was the primary driving factor influencing the ARGs distribution in whole-plant corn silage. Interestingly, whole-plant corn silage inoculated with Lent. buchneri reduced abundances of high-risk ARGs (mdtG, mepA, tetM, mecA, vatE and tetW) by regulating pathogens (Escherichia coli), mobile genetic elements (MGEs) genes (IS3 and IS1182), and this effect was more pronounced at 30 % DM level. In summary, although whole-plant corn silage inoculated with Lent. buchneri increased the total ARGs abundance at both DM levels, it decreased the abundance of high-risk ARGs by reducing the abundances of the pathogens and MGEs, and this effect was more noticeable at 30 % DM level.

A comparative evaluation of maize silage quality under diverse pre-ensiling strategies.

Maize silage serves as a significant source of energy and fibre for the diets of dairy and beef cattle. However, the quality of maize silage is contingent upon several crucial considerations, including dry matter loss, fermentative profile, pH level, ammonia content, and aerobic stability. These aspects are influenced by a multitude of factors and their interactions, with seasonality playing a crucial role in shaping silage quality. In this study an open-source database was utilised to assess the impact of various pre-ensiling circumstances, including the diversity of the chemical composition of the freshly harvested maize, on the silage quality. The findings revealed that seasonality exerts a profound influence on maize silage quality. Predictive models derived from the composition of freshly harvested maize demonstrated that metrics were only appropriate for screening purposes when utilizing in-field sensor technology. Moreover, this study suggests that a more comprehensive approach, incorporating additional factors and variability, is necessary to better elucidate the determinants of maize silage quality. To address this, combining data from diverse databases is highly recommended to enable the application of more robust algorithms, such as those from machine learning or deep learning, which benefit from large data sets.

Effect of sodium formate and lactic acid bacteria treated rye silage on methane yield and energy balance in Hanwoo steers.

This study was performed to evaluate the effects of rye silage treated with sodium formate (Na-Fa) and lactic acid bacteria (LAB) inoculants on the ruminal fermentation characteristics, methane yield and energy balance in Hanwoo steers. Forage rye was harvested in May 2019 and ensiled without additives (control) or with either a LAB inoculant or Na-Fa. The LAB (Lactobacillus plantarum) were inoculated at 1.5 × 1010 CFU/g fresh matter, and the inoculant was sprayed onto the forage rye during wrapping at a rate of 4 L/ton of fresh rye forage. Sixteen percent of the Na-Fa solution was sprayed at a rate of approximately 6.6 L/ton. Hanwoo steers (body weight 275 ± 8.4 kg (n = 3, group 1); average body weight 360 ± 32.1 kg (n = 3, group 2)) were allocated into two pens equipped with individual feeding gates and used in duplicated 3 × 3 Latin square design. The experimental diet was fed twice daily (09:00 and 18:00) during the experimental period. Each period comprised 10 days for adaptation to the pen and 9 days for measurements in a direct respiratory chamber. The body weights of the steers were measured at the beginning and at the end of the experiment. Feces and urine were collected for 5 days after 1 day of adaptation to the chamber, methane production was measured for 2 days, and ruminal fluid was collected on the final day. In the LAB group, the ratio of acetic acid in the rumen fluid was significantly lower (p = 0.044) and the ratio of propionic acid in the rumen fluid was significantly higher (p = 0.017). Methane production per DDMI of the Na-FA treatment group was lower than that of the other groups (p = 0.052), and methane production per DNDFI of the LAB treatment group was higher than that of the other groups (p = 0.056). The use of an acid-based additive in silage production has a positive effect on net energy and has the potential to reduce enteric methane emissions in ruminants.

Effects of brewery by-products based silage on productive performance of crossbred dairy cows.

The present study aimed to evaluate the effect of an increasing levels of brewery by-products based silage on productive performances of 3/4 Friesian x Boran mid-lactating cows. Experimental cows had similar in initial milk yield (11.7 ± 1.0), average days in milk (81.7 ± 6.1) and live weight (LW, 430.7 ± 40.3 kg) but different in parities (2-5).The dietary treatments were arranged randomly in 4 × 4 Latin Square Design that included ad libitum natural pasture hay feeding for all treatments as a roughage source plus a commercial dairy concentrate mix supplemented at 0.5 kg DM (dry matter)/liter of milk produced/day for cows in the control group (T1) and 0.3, 0.5 and 0.7 kg DM of brewery by-products based silage per liter of milk yield/cow/day for cows in T2, T3 and T4 groups, respectively. The study revealed that the daily milk yield of experimental cows was influenced by dietary treatments with relatively higher daily milk yield being recorded (P < 0.05) for cows in the T4 (13.9 l) followed by T3 (13.8 l). Milk composition of cows remained unchanged (P > 0.05) except for fat percentage of the milk that showed a declining trend (P < 0.05) with incremental inclusion levels of brewery by-products based silages. The highest net income (NI, 437.9 Eth. Birr) and marginal rate of return (MRR, 800.7%) was obtained for cows receiving brewery by-products based silage at the rate of 0.7 kg/liter of milk yield as compared to cows in the other treatment groups. Further study is required on the long term effect of brewery by-products based silage supplementation on productive, reproductive performance, and milk microbial qualities.

Adding rumen microorganisms to improve fermentation quality, enzymatic efficiency, and microbial communities of hybrid Pennisetum silage.

Hybrid Pennisetum, a top biomass energy source, faces usage limitations because of its scarce lactic acid bacteria and high fiber content. This study assessed the influence of rumen fluid pretreatment on hybrid Pennisetum's silage, with focus on silage duration and rumen fluid effects on quality and fiber decomposition. Advanced third-generation sequencing was used to track microbial diversity changes and revealed that rumen fluid considerably enhanced dry matter, crude protein, and water-soluble carbohydrates, thus improving fermentation quality to satisfactory pH levels (3.40-3.67). Ideal results, including the highest fiber breakdown and enzymatic efficiency (47.23 %), were obtained with 5 % rumen fluid in 60 days. The addition of rumen fluid changed the dominant species, including Paucilactobacillus vaccinostercus (0.00 % vs. 18.21 %) and Lactiplantibacillus plantarum (21.03 % vs. 47.02 %), and no Enterobacter was detected in the high-concentration treatments. Moreover, strong correlations were found between specific lactic acid bacteria and fermentation indicators, revealing the potential of achieving efficient and economically beneficial hybrid Pennisetum production.

Feed characteristics and potential effects on ruminal bacteria of ensiled sugar kelp and winged kelp for Holstein dairy cows.

Seaweed silage has potential as an alternative feed ingredient for dairy cows. This study aims to investigate seaweed's and seaweed silages nutrient digestibility as well as their impact on the ruminal bacterial composition. The cultivated S. latissima and A. esculenta were preserved by freezing at - 40 °C or ensiling (16 °C, 3 months) with four different treatments: no additives, 4 g formic acid/kg wet seaweed, lactic acid bacteria (LAB) inoculant, and LAB inoculant in prewilted biomass (ca. 300 g DM/kg wet biomass). The nutrient digestibility was estimated using standard feed evaluation methods. The bacterial composition in ruminal fluid after 48 h in vitro anaerobic incubation with seaweeds and common feedstuffs was analysed using 16S ribosomal RNA (rRNA) amplicon sequencing (V3-V4) and quantitative PCR (qPCR). The results suggest that S. latissima was more digestible than A. esculenta and that the preservation treatments had only a small effect on the nutrient digestibility and ruminal bacteria compositions. The rumen DM degradability of S. latissima was comparable to common perennial and corn forage; however, the total tract CP digestibility of S. latissima (460 g/kg CP) was lower than common forages (620 - 820 g/kg CP) and was not improved by ensiling. There was a lack of insoluble but rumen-degradable CP in A. esculenta, making it unsuitable as a nutrient ingredient for dairy cows. The ruminal bacterial composition changed depending on the seaweed species used as substrate: The dominant bacterial taxa when incubated with S. latissima belonged to the genus Prevotella (relative abundance: 79 - 93%), known for its ability to degrade polysaccharides in various ecosystems. Moreover, the fibrolytic bacteria including Fibrobacter succinogenes and Ruminococcus flavefaciens were > 2.5 Log2FoldChange higher when incubating with S. latissima than with A. esculenta. These bacterial taxa may play an important role in the in vitro organic matter digestibility, noted as 2 times higher in S. latissima compared to A. esculenta. The qPCR results indicated potential methane mitigation properties of the studied seaweed species, with significantly lower gene copies of Archaea 16S rRNA and methyl coenzyme-M reductase subunit A genes when the ruminal fluid was incubated with the seaweed substrates. Our study suggested that ensiled S. latissima biomass can be included in the diet of dairy cows as an alternative forage-like ingredient with the potential of methane mitigation.

Suitable fermentation temperature of forage sorghum silage increases greenhouse gas production: Exploring the relationship between temperature, microbial community, and gas production.

Silage is an excellent method of feed preservation; however, carbon dioxide, methane and nitrous oxide produced during fermentation are significant sources of agricultural greenhouse gases. Therefore, determining a specific production method is crucial for reducing global warming. The effects of four temperatures (10 °C, 20 °C, 30 °C, and 40 °C) on silage quality, greenhouse gas yield and microbial community composition of forage sorghum were investigated. At 20 °C and 30 °C, the silage has a lower pH value and a higher lactic acid content, resulting in higher silage quality and higher total gas production. In the first five days of ensiling, there was a significant increase in the production of carbon dioxide, methane, and nitrous oxide. After that, the output remained relatively stable, and their production at 20 °C and 30 °C was significantly higher than that at 10 °C and 40 °C. Firmicutes and Proteobacteria were the predominant silage microorganisms at the phylum level. Under the treatment of 20 °C, 30 °C, and 40 °C, Lactobacillus had already dominated on the second day of silage. However, low temperatures under 10 °C slowed down the microbial community succession, allowing, bad microorganisms such as Chryseobacterium, Pantoea and Pseudomonas dominate the fermentation, in the early stage of ensiling, which also resulted in the highest bacterial network complexity. According to random forest and structural equation model analysis, the production of carbon dioxide, methane and nitrous oxide is mainly affected by microorganisms such as Lactobacillus, Klebsiella and Enterobacter, and temperature influences the activity of these microorganisms to mediate gas production in silage. This study helps reveal the relationship between temperature, microbial community and greenhouse gas production during silage fermentation, providing a reference for clean silage fermentation.

Effects of two types of Coccomyxa sp. KJ on in vitro ruminal fermentation, methane production, and the rumen microbiota.

Coccomyxa sp. KJ is a unicellular green microalga that accumulates abundant lipids when cultured under nitrogen-deficient conditions (KJ1) and high nitrogen levels when cultured under nitrogen-sufficient conditions (KJ2). Considering the different characteristics between KJ1 and KJ2, they are expected to have different effects on rumen fermentation. This study aimed to determine the effects of KJ1 and KJ2 on in vitro ruminal fermentation, digestibility, CH4 production, and the ruminal microbiome as corn silage substrate condition. Five treatments were evaluated: substrate only (CON) and CON + 0.5% dry matter (DM) KJ1 (KJ1_L), 1.0% DM KJ1 (KJ1_H), 0.5% DM KJ2 (KJ2_L), and 1.0% DM KJ2 (KJ2_H). DM degradability-adjusted CH4 production was inhibited by 48.4 and 40.8% in KJ2_L and KJ2_H, respectively, compared with CON. The proportion of propionate was higher in the KJ1 treatments than the CON treatment and showed further increases in the KJ2 treatments. The abundances of Megasphaera, Succiniclasticum, Selenomonas, and Ruminobacter, which are related to propionate production, were higher in KJ2_H than in CON. The results suggested that the rumen microbiome was modified by the addition of 0.5-1.0% DM KJ1 and KJ2, resulting in increased propionate and reduced CH4 production. In particular, the KJ2 treatments inhibited ruminal CH4 production more than the KJ1 treatments. These findings provide important information for inhibiting ruminal CH4 emissions, which is essential for increasing animal productivity and sustaining livestock production under future population growth.

Effects of grass species and harvest date on cell wall components and feed efficiency of dairy cows.

There is a balance between DM yield and feed value when choosing types of grasses on a farm depending on the acreages of farmland and types of ruminants to be fed. Therefore, optimisation of the harvest strategy for grass silage is important for profitable dairy farming. Tall fescue has high DM yield and can replace traditional grasses, such as timothy, in Northern Europe in a changing climate as it has been shown to be more drought tolerant. As differences in climate responses previously have been related to differences in cell wall structure between grass species and, consequently, in digestibility, it is highly relevant to compare these species at similar maturity stages and to investigate if a very early harvest date will diminish potential differences between the species. This study evaluated the effects of harvest date and forage species on the concentration of hydroxycinnamic acids in silages and its relationship to feed efficiency of dairy cows. Tall fescue and timothy were harvested at very early date on May 25 or at early date on May 31 in the spring growth cycle. Forty lactating dairy cows were used in a block design. Cows received 1 of 4 treatments: (1) tall fescue harvested at very early date, (2) timothy harvested at very early date, (3) tall fescue harvested at early date, and (4) timothy harvested at early date. Diets were formulated to have the same forage-to-concentrate ratio (49:51 on DM basis). Tall fescue silages showed greater concentrations of DM, ash, and CP than timothy silages. Grasses harvested at early date showed greater concentrations of NDF, ADL, and cell wall than grasses harvested at very early date. Tall fescue silages showed greater concentration of p-coumaric acid and lower in vitro organic matter digestibility (IVOMD) compared to timothy silages. Milk production and composition were not affected by treatments but cows fed tall fescue-based diets showed lower milk protein yield and greater milk urea nitrogen than when timothy-based diets were fed. Furthermore, cows receiving timothy-based diets showed greater feed efficiency compared to cows receiving tall fescue-based diets. Thus, the lower concentration of p-coumaric acid and the higher IVOMD was associated with greater feed efficiency of cows fed timothy-based diets compared to tall fescue-based diets.

Handheld Near-Infrared Spectroscopy for Undried Forage Quality Estimation.

This study investigates the efficacy of handheld Near-Infrared Spectroscopy (NIRS) devices for in-field estimation of forage quality using undried samples. The objective is to assess the precision and accuracy of multiple handheld NIRS instruments-NeoSpectra, TrinamiX, and AgroCares-when evaluating key forage quality metrics such as Crude Protein (CP), Neutral Detergent Fiber (aNDF), Acid Detergent Fiber (ADF), Acid Detergent Lignin (ADL), in vitro Total Digestibility (IVTD)and Neutral Detergent Fiber Digestibility (NDFD). Samples were collected from silage bunkers across 111 farms in New York State and scanned using different methods (static, moving, and turntable). The results demonstrate that dynamic scanning patterns (moving and turntable) enhance the predictive accuracy of the models compared to static scans. Fiber constituents (ADF, aNDF) and Crude Protein (CP) show higher robustness and minimal impact from water interference, maintaining similar R2 values as dried samples. Conversely, IVTD, NDFD, and ADL are adversely affected by water content, resulting in lower R2 values. This study underscores the importance of understanding the water effects on undried forage, as water's high absorption bands at 1400 and 1900 nm introduce significant spectral interference. Further investigation into the PLSR loading factors is necessary to mitigate these effects. The findings suggest that, while handheld NIRS devices hold promise for rapid, on-site forage quality assessment, careful consideration of scanning methodology is crucial for accurate prediction models. This research contributes valuable insights for optimizing the use of portable NIRS technology in forage analysis, enhancing feed utilization efficiency, and supporting sustainable dairy farming practices.

Mycotoxin production in different varieties of Dactylis glomerata L. silage in response to biological and chemical additives.

Silage has been identified as a source of different microbial toxins, that may impair farm animal health and productivity as human health can also be compromised. In this sense, the aim of this study was to determine the impact of silage additives on the concentrations of deoxynivalenol (DON) and zearalenone (ZEN) mycotoxins and, eventually, to evaluate the hygienic quality of orchardgrass (Dactylis glomerata L.) silage based on the concentration of them compared to control silage. This study evaluated the influence of biological and chemical additives used in six different varieties of orchardgrass silage on DON and ZEN mycotoxin contents for the first time. The content of both fusariotoxins (DON and ZEN) in fresh matter and grass silage were below the threshold stipulated by the European Commission. The concentration of DON ranges from ~21.86 to 37.26 ng/kg, ~10.21 to 15 ng/kg, ~20.72 to 29.14 ng/kg; and ZEN range from ~3.42 to 7.87 ng/kg, ~3.85 to 8.62 ng/kg and ~2.15 to 5.08 ng/kg, in control, biological and chemical silages, respectively. In general, the biological additive was more efficient for preventing DON contamination, whereas the chemical additive was more efficient for preventing ZEN contamination in grass silage. In summary, the results obtained in this work demonstrate that biological and chemical additives can inhibit fungal growth and mycotoxin production on Dactylis glomerata L. silage and whose use could prevent animal and human diseases.

Lacticaseibacillus parahuelsenbergensis sp. nov., Lacticaseibacillus styriensis sp. nov. and Lacticaseibacillus zeae subsp. silagei subsp. nov., isolated from different grass and corn silage.

Four rod-shaped, non-motile, non-spore-forming, facultative anaerobic, Gram-stain-positive lactic acid bacteria, designated as EB0058T, SCR0080, LD0937T and SCR0063T, were isolated from different corn and grass silage samples. The isolated strains were characterized using a polyphasic approach and EB0058T and SCR0080 were identified as Lacticaseibacillus zeae by 16S rRNA gene sequence analysis. Based on whole-genome sequence-based characterization, EB0058T and SCR0080 were separated into a distinct clade from Lacticaseibacillus zeae DSM 20178T, together with CECT9104 and UD2202, whose genomic sequences are available from NCBI GenBank. The average nucleotide identity (ANI) values within the new subgroup are 99.9 % and the digital DNA-DNA hybridization (dDDH) values are 99.3-99.9 %, respectively. In contrast, comparison of the new subgroup with publicly available genomic sequences of L. zeae strains, including the type strain DSM 20178T, revealed dDDH values of 70.2-72.5 % and ANI values of 96.2-96.6 %. Based on their chemotaxonomic, phenotypic and phylogenetic characteristics, EB0058T and SCR0080 represent a new subspecies of L. zeae. The name Lacticaseibacillus zeae subsp. silagei subsp. nov. is proposed with the type strain EB0058T (=DSM 116376T=NCIMB 15474T). According to the results of 16S rRNA gene sequencing, LD0937T and SCR0063T are members of the Lacticaseibacillus group. The dDDH value between the isolates LD0937T and SCR0063T was 67.6 %, which is below the species threshold of 70 %, clearly showing that these two isolates belong to different species. For both strains, whole genome-sequencing revealed that the closest relatives within the Lacticaseibacillus group were Lacticaseibacillus huelsenbergensis DSM 115425 (dDDH 66.5 and 65.9 %) and Lacticaseibacillus casei DSM 20011T (dDDH 64.1 and 64.9 %). Based on the genomic, chemotaxonomic and morphological data obtained in this study, two novel species, Lacticaseibacillus parahuelsenbergensis sp. nov. and Lacticaseibacillus styriensis sp. nov. are proposed and the type strains are LD0937T (=DSM 116105T=NCIMB 15471T) and SCR0063T (=DSM 116297T=NCIMB 15473T), respectively.

Impact of replacing protein pellets with soybean grain on nutrient utilization and the rumen and blood parameters of feedlot cattle under tropical conditions.

The aim of this study was to explore the effect of replacing protein pellets with soybean grain in high-concentrate diets with or without the addition of silage, on the intake, digestibility, and rumen and blood parameters of feedlot cattle in tropical regions. Four cannulated, crossbred steers were used, 4.5 ± 0.5 years old, with an average weight of 685.55 ± 111.78 kg. The steers were distributed in a 4 × 4 Latin square, in a 2 × 2 factorial scheme (two sources of protein: protein pellets or whole soybean grain, with or without added dietary bulk). There was no effect (P ≥ 0.109) from the interaction between the source of protein and the addition of silage to the diet on dry matter (DM) and nutrient intake, or the digestibility (P ≥ 0.625) of DM or crude protein (CP). However, both factors affected (P ≤ 0.052) the intake of DM, neutral detergent fiber (NDF), and non-fiber carbohydrates (NFC), as well as the independent digestibility (P ≤ 0.099) of fat, NFC, total carbohydrates (TC), and total cholesterol concentration. There was an effect (P ≤ 0.053) from the interaction between the source of protein and the addition of silage to the diet on the digestibility of NDF and total digestible nutrients (TDN), as well as on the glycose concentration (P = 0.003). Blood parameters (i.e. protein, albumin, creatinine, triglycerides, aspartate aminotransferase (AST), and alanine aminotransferase (ALT)) were not affected (P ≥ 0.139) by the source of protein, the addition of silage, or their interaction. Lastly, including 150 g/kg silage DM in a high-grain diet, and using soybean grain as a source of protein in substitution of protein pellet could be a suitable nutritional strategy to ensure adequate DM and nutrient intake and digestibility, with no detrimental effects on rumen and blood parameters of feedlot cattle in the tropics.

Changes in microbial dynamics and fermentation characteristics of alfalfa silage: A potent approach to mitigate greenhouse gas emission through high-quality forage silage.

Feeding ruminants with high-quality forage can enhance digestibility and reduce methane production. Development of high-quality silage from leguminous plants with lactic acid bacteria can improve digestibility and it mitigate the greenhouse gas emissions. In this study, we developed a high-quality alfalfa silage with improved fermentation index and microbial dynamics using Levilactobacillus brevis-KCC-44 at low or high moisture (LM/HM) conditions and preserved it for 75 or 150 days. Alfalfa fermentation with L. brevis enhances acidification and fermentation characteristics primarily due to the dominance of lactic acid bacteria (LAB) L. brevis (>95%) compared to alfalfa fermented with epiphytic LAB. The inoculant L. brevis improved the anaerobic fermentation indexes resulting in a higher level of lactic acid in both high (10.0 ± 0.12 & 8.90 ± 0.31%DM) and low moisture (0.55 ± 0.08 & 0.39 ± 0.0 %DM) in 75 and 150 days respectively, compared to control silage. In addition, the marginal amount of acetic acid (range from 0.23 ± 0.07 to 2.04 ± 0.27 %DM) and a reduced level of butyric acid (range between 0.03 ± 0.0 to 0.13 ± 02 %DM) was noted in silage treated with LAB than the control. The LAB count and abundance of Levilactobacillus were higher in alfalfa silage fermented with L. brevis. Microbial richness and diversity were reduced in alfalfa silage treated with L. brevis which prompted lactic acid production at a higher level even for a prolonged period of time. Therefore, this L.brevis is an effective inoculant for producing high-quality alfalfa silage since it improves fermentation indexes and provides reproducible ensiling properties.

Effect of harvesting strategy of second-cut orchardgrass silage on feed intake, digestion, and milk production in dairy cows.

We investigated the effects of regrowth interval and first-cut timing on the dietary characteristics of second-cut orchardgrass silage and feed intake and milk production in dairy cows fed second-cut orchardgrass silage. The second-cut grasses were harvested 7w after the first-cut at the early stage (E7w) or at the heading stage (H7w), or harvested 6w after the first-cut at the early stage (E6w) from orchardgrass sward, and then ensiled. We evaluated the effect of regrowth interval by comparing E7w and E6w, and the effect of first-cut timing by comparing E7w and H7w. Six multiparous Holstein cows were used in a replicated 3 × 3 Latin square design, with three dietary treatments: diets containing E7w, E6w, or H7w silage at 30% dietary dry matter. We observed that feeding E6w silage instead of E7w silage increased fiber digestibility, dry matter intake, and milk production; however, the first-cut timing (E7w vs. H7w) did not affect nutrient content and digestibility, feed intake, or lactation performance. These results show that harvesting at short regrowth intervals for second-cut orchardgrass can be an effective strategy for improving feed utilization and milk yield; however, the first-cut timing for second-cut orchardgrass has little impact.

Remodeling of intestinal bacterial community and metabolome of Dezhou donkey induced by corn silage.

Corn silage can usually improve the growth performance and the meat quality of ruminants, and subsequently increase the economic benefits of farming. However, little is known about the effects of corn silage on donkeys. This experiment investigated the effects of corn silage on the weight gain, gut microbiota and metabolites of Dezhou donkeys. A total of 24 Dezhou donkeys, sourced from the same farm and exhibiting similar age and average body weight, were utilized in this experiment. The donkeys were allocated into two groups: a control group receiving a basic diet and a test group receiving a basic diet supplemented with 30% corn silage. Each group comprised 12 donkeys, evenly distributed by sex (6 males and 6 females). The experiment lasted for 100 days. Results showed that dietary supplementation with corn silage significantly (P < 0.05) improved the weight gain of Dezhou donkeys at the end of the experiment. And the supplementation of corn silage in the diet significantly altered the bacterial community composition and metabolome in the feces of the donkeys. Notably, the relative abundance ratio of Bacteroidetes to Firmicutes was 0.76 in the control group compared to 0.96 in the test group. Furthermore, members of the Bacteroidetes and Firmicutes phyla were associated with differentiated metabolites enriched in the arachidonic acid metabolism and pentose and glucuronate interconversion pathways, both of which have been reported to be related to animal growth. Specifically, Bacteroidia exhibited statistically (P < 0.05) positive correlations with 15S-HpETE, while Bacilli demonstrated statistically (P < 0.05) negative correlations with D-Xylulose. The findings of this study can advance our mechanistic understanding of the remodeling of intestinal microbiota and metabolome induced by corn silage, as well as their relationships with the growth performance of Dezhou donkeys, which in turn favor the improvement in nutrition of Dezhou donkeys.