Possibility of Using By-Products with High NDF Content to Alter the Fecal Short Chain Fatty Acid Profiles, Bacterial Community, and Digestibility of Lactating Dairy Cows

Formation of high-quality mixed silage from paper mulberry and wheat bran driven by the characteristics of the microbial community

Paper mulberry (Broussonetia papyrifera) is a high-quality silage protein feed material that can help address feed shortages and support livestock development. Although some studies have investigated the relationships between microbial communities and silage quality, these relationships and the underlying community assembly processes remain complex, requiring further research to clarify them. Additionally, limited research has explored the relationship between microbial community fermentation functions and silage quality. In this study, we aimed to explore B. papyrifera and wheat bran mixed silage quality driven by the characteristics of the microbial community. After 50 days of silage fermentation, high-quality and low-quality samples were selected from every mixing ratio (90:10, 80:20, and 65:35). The silage chemical composition, lignocellulose degradation enzyme activity, microbial community composition, and potential functions were used to explore the relevance between silage quality and the characteristics of the microbial community. The contents of hemicellulose, neutral detergent fiber, pH, and the activities of endoglucanase and exoglucanase were significantly affected by mixing ratios and silage quality grade. There were higher crude protein content, lignocellulose degrading enzyme activity, and lower pH, lignin, and acid detergent fiber in the mixing of 65:35 (BP65%) samples. The PERMANOVA results showed that mixing ratios had significant impacts on microbial community composition and bacterial fermentation functions. There was a higher bacterial diversity, lower fungal diversity, and better functional potentials for fermentation and lignocellulose degradation in BP65% high-quality silage. The dominant genera were Lactobacillus, Cladosporium, and Wallemia in all samples. The relative abundance of Clostridium, Rhodococcus, Turicibacter, Ralstonia, and Burkholderia was significantly higher in BP65% high-quality samples. There was a higher abundance of Wallemia in the BP65% samples than in other mixing ratios samples. Notably, silage quality showed a close relationship with Lactobacillus, Turicibacter, Romboutsia, Wallemia, and Pichia. In summary, 65:35 was a suitable mixing ratio for B. papyrifera and wheat bran silage, but high-quality silage still required the participation of multiple specific rare microbial taxa. The higher bacterial diversity and specific microbial taxa abundance could be critical for improving B. papyrifera silage quality. We expect that our findings will provide new insights into silage quality driven by the characteristics of the microbial community.

Metabolic Characteristics of Gut Microbiota and Insomnia: Evidence from a Mendelian Randomization Analysis

Insomnia is a common sleep disorder that significantly impacts individuals' sleep quality and daily life. Recent studies have suggested that gut microbiota may influence sleep through various metabolic pathways. This study aims to explore the causal relationships between the abundance of gut microbiota metabolic pathways and insomnia using Mendelian randomization (MR) analysis. This two-sample MR study used genetic data from the OpenGWAS database (205 gut bacterial pathway abundance) and the FinnGen database (insomnia-related data). We identified single nucleotide polymorphisms (SNPs) associated with gut bacterial pathway abundance as instrumental variables (IVs) and ensured their validity through stringent selection criteria and quality control measures. The primary analysis employed the inverse variance-weighted (IVW) method, supplemented by other MR methods, to estimate causal effects. The MR analysis revealed significant positive causal effects of specific carbohydrate, amino acid, and nucleotide metabolism pathways on insomnia. Key pathways, such as gluconeogenesis pathway (GLUCONEO.PWY) and TCA cycle VII acetate producers (PWY.7254), showed positive associations with insomnia (B > 0, p < 0.05). Conversely, pathways like hexitol fermentation to lactate, formate, ethanol and acetate pathway (P461.PWY) exhibited negative causal effects (B < 0, p < 0.05). Multivariable MR analysis confirmed the independent causal effects of these pathways (p < 0.05). Sensitivity analyses indicated no significant pleiotropy or heterogeneity, ensuring the robustness of the results. This study identifies specific gut microbiota metabolic pathways that play critical roles in the development of insomnia. These findings provide new insights into the biological mechanisms underlying insomnia and suggest potential targets for therapeutic interventions. Future research should further validate these causal relationships and explore how modulating gut microbiota or its metabolic products can effectively improve insomnia symptoms, leading to more personalized and precise treatment strategies.

Fermented total mixed ration enhances nutrient digestibility and modulates the milk components and fecal microbial community in lactating Holstein dairy cows

Fermented total mixed ration (FTMR) is an effective method of preserving high-moisture byproducts with higher aerobic stability after fermentation. FTMR has the potential to fulfill the daily nutritional requirements of cattle and enhance their production performance. The objective of this research was to examine the influence of FTMR on lactation performance, total tract apparent digestibility, fecal microbiota communities, and fermentation profiles in lactating dairy cows. A total of 12 cows were randomly assigned into two groups: the TMR group and the FTMR group. The TMR group was fed a total mixed ration (TMR) diet, and the FTMR group was fed an FTMR diet. The FTMR did not impact milk yield in dairy cows despite a decrease in dry matter intake, which increased the efficiency of the feed. In contrast to that in the TMR group, the milk fat content in the FTMR group was greater. The FTMR group showed greater digestibility of neutral detergent fiber (NDF), organic matter (OM), dry matter (DM), crude protein (CP), and acid detergent fiber (ADF) in the total digestive tract than did the TMR group. The FTMR increased the concentration of butyrate in the fecal matter and reduced the pH of the feces. The Chao1, ACE, and Shannon indices of the archaeal community in dairy cow feces were significantly higher in cow fed the FTMR compared to those fed the TMR. LefSe analysis revealed higher levels of Oscillospira, Lactobacillus, Prevotella, and Dehalobacterium in the feces of dairy cows fed the FTMR than in those fed the TMR. However, the abundances of Roseburia, rc4-4, Bulleidia and Sharpea exhibited the opposite trend. The abundances of Halobacteria, Halobacteriales, and Halobacteriaceae, which are biomarkers for distinguishing fecal archaea in the TMR from the FTMR, were substantially greater in the feces of dairy cows that consumed the TMR than in those that consumed the FTMR. Therefore, FTMR can improve the milk fat content, total tract apparent feed digestibility efficiency, and diversity of archaea in the feces. Additionally, this work provides a theoretical basis for the feasibility of FTMR feeding for dairy cows.

Temporal and geographic distribution of gut microbial enterotypes associated with host thermogenesis characteristics in plateau pikas

IMPORTANCE

The gut microbiotas of small mammals play an important role in host energy homeostasis. However, it is still unknown whether small mammals with different enterotypes show differences in thermogenesis characteristics. Our study confirmed that plateau pikas with different bacterial enterotypes harbored distinct thermogenesis capabilities and employed various strategies against cold environments. Additionally, we also found that pikas with different fungal enterotypes may display differences in coprophagy.

Effects of Heated Drinking Water during the Cold Season on Serum Biochemistry, Ruminal Fermentation, Bacterial Community, and Metabolome of Beef Cattle

This study explored the effects of drinking heated water in the cold seasons on the serum metabolism, rumen microbial fermentation, and metabolome of beef cattle. Twelve fattening cattle (642 ± 14.6 kg) aged 21 to 22 months were randomly and equally divided into two groups based on body weight: one receiving room-temperature water (RTW; average 4.39 ± 2.55 °C) and the other heated water (HW; average 26.3 ± 1.70 °C). The HW group displayed a significant decrease in serum glucose (p < 0.01) and non-esterified fatty acid (p < 0.01), but increases in insulin (p = 0.04) and high-density lipoprotein (p = 0.03). The rumen fermentation parameters of the HW group showed substantial elevations in acetate (p = 0.04), propionate (p < 0.01), isobutyrate (p = 0.02), and total volatile fatty acids (p < 0.01). Distinct bacterial composition differences were found between RTW and HW at the operational taxonomic unit (OTU) level (R = 0.20, p = 0.01). Compared to RTW, the HW mainly had a higher relative abundance of Firmicutes (p = 0.07) at the phylum level and had a lower abundance of Prevotella (p < 0.01), norank_f_p-215-o5 (p = 0.03), and a higher abundance of NK4A214_group (p = 0.01) and Lachnospiraceae_NK3A20_group (p = 0.05) at the genus level. In addition, NK4A214_group and Lachnospiraceae_NK3A20_group were significantly positively correlated with the rumen propionate and isovalerate (r > 0.63, p < 0.05). Prevotella was negatively correlated with rumen propionate and total volatile fatty acids (r = -0.61, p < 0.05). In terms of the main differential metabolites, compared to the RTW group, the expression of Cynaroside A, N-acetyl-L-glutamic acid, N-acetyl-L-glutamate-5-semialdehyde, and Pantothenic acid was significantly upregulated in HW. The differentially regulated metabolic pathways were primarily enriched in nitrogen metabolism, arginine biosynthesis, and linoleic acid metabolism. Prevotella was significantly positively correlated with suberic acid and [6]-Gingerdiol 3,5-diacetate (r > 0.59, p < 0.05) and was negatively correlated with Pantothenic acid and isoleucyl-aspartate (r < -0.65, p < 0.05). NK4A214_group was positively correlated with L-Methionine and glycylproline (r > 0.57, p < 0.05). Overall, our research demonstrates the important relationship between drinking water temperature and metabolic and physiological responses in beef cattle. Heating drinking water during cold seasons plays a pivotal role in modulating internal energy processes. These findings underscore the potential benefits of using heated water as a strategic approach to optimize energy utilization in beef cattle during the cold seasons.

Heating Drinking Water in Cold Season Improves Growth Performance via Enhancing Antioxidant Capacity and Rumen Fermentation Function of Beef Cattle

The research aimed to investigate the suitable drinking water temperature in winter and its effect on the growth performance, antioxidant capacity, and rumen fermentation function of beef cattle. A total of 40 beef cattle (640 ± 19.2 kg) were randomly divided into five treatments with eight cattle in each treatment raised in one pen according to initial body weight. Each treatment differed only in the temperature of drinking water, including the room-temperature water and four different heat water groups named RTW, HW_1, HW_2, HW_3, and HW_4. The measured water temperatures were 4.39 ± 2.546 °C, 10.6 ± 1.29 °C, 18.6 ± 1.52 °C, 26.3 ± 1.70 °C, and 32.5 ± 2.62 °C, respectively. The average daily gain (ADG) showed a significant linear increase during d 0 to 60 and a quadratic increase during d 31 to 60 with rising water temperature (p < 0.05), and the highest ADG of 1.1911 kg/d was calculated at a water temperature of 23.98 °C (R2 = 0.898). The average rectal temperature on d 30 (p = 0.01) and neutral detergent fiber digestibility (p < 0.01) increased linearly with increasing water temperature. Additionally, HW_2 reduced serum triiodothyronine, thyroxine, and malondialdehyde (p < 0.05), and increased serum total antioxidant capacity (p < 0.05) compared with RTW. Compared with HW_2, RTW had unfavorable effects on ruminal propionate, total volatile fatty acids, and cellulase concentrations (p < 0.05), and lower relative mRNA expression levels of claudin-4 (p < 0.01), occludin (p = 0.02), and zonula occludens-1 (p = 0.01) in the ruminal epithelium. Furthermore, RTW had a higher abundance of Prevotella (p = 0.04), Succinivibrionaceae_UCG-002 (p = 0.03), and Lachnospiraceae_UCG-004 (p = 0.03), and a lower abundance of Bifidobacteriaceae (p < 0.01) and Marinilabiliaceae (p = 0.05) in rumen compared to HW_2. Taken together, heated drinking water in cold climates could positively impact the growth performance, nutrient digestibility, antioxidant capacity, and rumen fermentation function of beef cattle. The optimal water temperature for maximizing ADG was calculated to be 23.98 °C under our conditions. Ruminal propionate and its producing bacteria including Prevotella, Succinivibrionaceae, and Lachnospiraceae might be important regulators of rumen fermentation of beef cattle drinking RTW under cold conditions.

The Effect of Indigo (Indigofera tinctoria L.) Waste on Growth Performance, Digestibility, Rumen Fermentation, Hematology and Immune Response in Growing Beef Cattle

This experiment was conducted to assess the effect of indigo waste on the feed intake, digestibility, rumen fermentation, hematology, immune response and growth performance in growing beef cattle. Twenty crossbred beef cattle with an initial body weight (BW) of 145 ± 11 kg were fed four levels of indigo waste for 90 days in a trial. Additions of indigo waste at 0%, 10%, 20% and 30% in a concentrate diet using a completely randomized design (CRD). Cattle were fed concentrate at 1.8% BW, with rice straw fed ad libitum. The concentrate intake decreased linearly (p = 0.01) with the addition of indigo waste. The supplementation with indigo waste reduced dry matter (DM) and organic matter (OM) digestibility cubically (p = 0.03 and p = 0.02, respectively), while increasing neutral detergent fiber (NDF) digestibility cubically (p = 0.02). The final BW of beef cattle decreased linearly (p = 0.03) with the addition of indigo waste. The inclusion of indigo waste decreased the average daily gain (ADG) and gain-to-feed ratio (G:F) linearly (p < 0.01) from 0 to 90 days. The nutrient digestibility, ADG and G:F of beef cattle fed 10% indigo waste in the diet was similar when compared with the control (0% indigo waste). The ruminal pH, ammonia-nitrogen (NH3-N) and total volatile fatty acid (VFA) concentrations were similar among treatments (p > 0.05). The proportion of acetate increased linearly (p < 0.01) but propionate decreased linearly (p < 0.01), resulting in an increase in the acetate to propionate ratio (p < 0.01) when cattle were fed with indigo waste supplementation. Increasing indigo waste levels did not influence blood urea nitrogen (BUN) levels, hematological parameters or immune responses (IgA, IgM and IgG) (p > 0.05). In conclusion, the inclusion of indigo waste at 10% in a concentrate diet did not have a negative effect on feed intake, nutrient digestibility, rumen fermentation, hematology, immune function or growth performance in growing beef cattle.