After weaning, calves undergo a critical transition from liquid milk to solid feed. During this period, the digestive system is not yet fully mature and the rumen microbial community is still being established, which can easily lead to stress responses, growth retardation and other problems. Nutritional management and microecological regulation at this stage are crucial for rumen development, maturation of immune function and subsequent growth performance. Probiotics are regarded as an important nutritional and microecological strategy to alleviate weaning stress and promote the maturation of rumen and intestinal function. Therefore, in the present study, sixteen 8-month-old weaned yaks were randomly allocated to two groups (n = 8 per group): a composite probiotic group (CP) and a control group (CK). In the CP group, a composite probiotic preparation (Bacillus subtilis, Lactobacillus acidophilus and Bacillus licheniformis; viable count ≥ 1 × 1010 CFU/g) was supplemented at 0.2

Hypobaric hypoxia poses a serious threat to growth and development and can induce pronounced inflammatory responses. These effects are closely associated with the gut microbiota. However, the underlying mechanisms, particularly the role of gut microbiota in regulating hepatic metabolism under chronic hypoxic conditions, remain poorly understood. In this study, SD rats were used as recipients and assigned to three groups: a hypobaric hypoxia group (H), an antibiotic-treated group (HA), and an antibiotic-treated group receiving fecal microbiota transplantation from plateau zokors (HAM). All rats were maintained in a hypobaric hypoxia chamber simulating an altitude of 6000 m for 30 days. Subsequently, growth performance, routine hematological parameters, and multi-omics profiles were evaluated. Compared with the H group, both the HAM and HA groups showed significantly increased average daily gain (ADG) (p < 0.05), while the ADG/ADFI ratio was significantly higher in the HAM group than in the H group (p < 0.05). Monocyte count (Mon#) and monocyte percentage (Mon%) were significantly higher in the HA group than in both the H and HAM groups (p < 0.05). Microbiota analysis revealed significant enrichment of Lachnospiraceae_NK4A136_group in the HAM group, whereas Desulfovibrio was significantly enriched in the HA group (p < 0.05). Fecal metabolomics showed that ursodeoxycholic acid (UDCA) was significantly increased in the HAM group (p < 0.05). In the liver metabolome, the anti-inflammatory lipid FAHFA 18:1/20:3 was significantly elevated in the HAM group, whereas pro-inflammatory factors, including uric acid and leukotriene D4, were significantly reduced (p < 0.05). Correlation analysis further demonstrated that the abundance of Lachnospiraceae was positively correlated with FAHFA 18:1/20:3 and negatively correlated with uric acid and creatinine (p < 0.05). Collectively, these findings indicate that the gut microbiota can modulate gut-liver metabolism, alleviate inflammatory responses, and enhance the adaptation of rats to hypoxic environments. This study provides valuable insights into potential strategies for promoting sustainable animal health and adaptation under hypoxic conditions.

Background This study investigated the effects of rumen fluid-fermented roughage on the rumen microbiota and the growth performance of yaks. Twenty yaks with similar body conditions were randomly divided into two groups (n = 10 per group), and fed either a basal diet (CON) or 10% rumen fluid-fermented roughage. The experiment lasted 75 d, including a 15 d adaptation period and a 60 d treatment period. At the end of the experiment, serum and rumen fluid samples were collected and analyzed. The microbial communities and metabolomic profiles in the rumen fluid were analyzed using 16S rRNA sequencing and non-targeted metabolomics, respectively. Results Results showed a significant rise in serum alanine aminotransferase levels, while serum total protein and cholesterol concentrations decreased notably. Furthermore, rumen fluid ammonia nitrogen and acetic acid concentrations decreased significantly, while concentrations of yak rumen microbial protein, isovaleric acid, and valeric acid increased significantly. Rumen microbial diversity was enhanced, with decreased abundances of Firmicutes , Cyanobacteria , Klebsiella , Spirochaetota , fungi, and Pseudomonas , alongside increased populations of Anaeroplasma , Spirochaetota , Fibrobacter , and Succiniclasticum . Furthermore, the activity of the bile secretion pathway and concentrations of its metabolites—including deoxycholic acid, chenodeoxycholic acid, glycocholic acid, and glycodeoxycholic acid—were significantly elevated. Conclusions These findings indicate that rumen fluid-fermented coarse feed not only promotes yak growth but also enhances health by modulating metabolites associated with cellular proliferation, such as dUMP, adenylosuccinate, and DL-α-tocopherol. Consequently, rumen fluid-fermented coarse feed represents a beneficial dietary supplement for improving growth performance and overall health in yaks.

Pretreating feed via fermentation to enhance its nutritional value is effective for young ruminants. This study optimized fermented feed using a microbial consortium of Saccharomyces cerevisiae, Bacillus licheniformis, and Enterococcus faecalis, and explored its mechanisms on growth performance and ruminal function in goat kids. The Bacillus licheniformis is the most critical determinant of the nutritional value of FF. Optimized FF had higher levels of crude protein, calcium, phosphorus, and limiting amino acids (AA). The FF contained viable microbiota with lower diversity but greater evenness. The microbiota was enriched in AA and carbohydrate metabolism by enhancing the abundance of Leuconostoc lactis and Lactococcus lactis. A 40-day feeding trial was then conducted with 20-day-old goat kids. Compared to conventional feed, FF increased feed digestibility, body weight and carcass weight. Mechanistically, FF enhanced the interactions among rumen microbes and increased the gene abundance related to carbohydrate and AA metabolism. The FF then upregulated expression of mitochondrial respiratory chain-related genes in the rumen epithelium, thereby improving epithelial energy metabolism. Overall, this study shows that fermented feed optimized by microbial consortium improves goat kid growth and carcass quality through the fermented feed-rumen microbiota axis, offering a sustainable approach for ruminant production.

The yak is an iconic ruminant of the Qinghai-Tibet Plateau, yet segment-specific variation in its intestinal microbial functional potential and bile acid profiles under different feeding systems remains insufficiently characterized. Six healthy adult male yaks with similar body weights (320 ± 30 kg) were assigned to grazing (G) or stall-feeding (S) systems, with three animals per group, for a 90-day trial comprising a 10-day adaptation period and an 80-day formal experimental period. The individual yak was considered the experimental unit, and intestinal segments sampled from the same animal were treated as repeated observations. Liver tissue and digesta from the duodenum, ileum, cecum, and colon were analyzed using targeted bile acid metabolomics and shotgun metagenomics. Principal coordinate analysis based on Bray-Curtis dissimilarities showed segment-associated clustering of microbial communities, with PCo1 and PCo2 explaining 65.5% and 18.9% of the total variation, respectively. ANOSIM identified a significant intestinal-segment effect on microbial community composition (R = 0.2208, BH-FDR = 0.0144), whereas the overall feeding-system effect was not significant (R = 0.3747, BH-FDR = 0.1200). No statistically significant feeding-system differences were detected in Shannon, Simpson, Chao1, or ACE indices within individual intestinal segments (BH-FDR ≥ 0.800), and PERMDISP detected no significant differences in within-group dispersion (BH-FDR ≥ 0.1682). Bacillota and Bacteroidota were the dominant phyla. Descriptive functional profiling showed higher mean ileal abundances of GH2 (0.0035 vs. 0.0026), GH3 (0.0029 vs. 0.0024), and GH43 (0.0021 vs. 0.0013) in grazing yaks, whereas the starch-associated GH13 family showed its highest mean abundance in the colon of stall-fed yaks. These metagenomic patterns represent predicted genomic functional potential rather than gene expression, enzyme activity, or metabolic flux. Cecal total bile acid concentration showed a nominal between-group difference (unadjusted Welch’s p = 0.0109), but this difference did not remain significant after correction across the five anatomical sites (BH-FDR = 0.0545). In the colon, stall-fed yaks had a lower conjugated-to-unconjugated bile acid ratio and a higher secondary-to-primary bile acid ratio than grazing yaks (BH-FDR < 0.05). Feeding-system-associated descriptive patterns were observed in predicted microbial functional profiles, whereas statistically supported between-group differences were limited mainly to selected colonic bile acid ratios. Given the limited animal-level replication, these findings should be considered exploratory.

Fermented soybean meal (FSM) can improve protein utilization efficiency but is easily degraded in the rumen; therefore, it cannot provide sufficient metabolizable protein (MP) for dairy cows. Here, the rumen degradation characteristics of FSM combined with tannin extracts from quebracho or chestnut trees or heat-treated were investigated regarding in vitro gas production and in situ in the rumens of three fistulated cows. The results of the rumen in situ incubation showed that the dry matter (DM) degradation rate decreased in the three rumen treatments. Compared with those of the FSM, the effective degradation rate of the FSM with chestnut tannin was significantly reduced and the rumen undegradable protein was significantly increased. The MP% (DM%) and MP (DM% × DM recovery) indicators in the FSM with chestnut or quebracho tannins increased, but the difference was not significant, whereas those of the FSM decreased following heat treatment. The results concerning in vitro gas production showed that tannin could reduce the rate of biogas production of the slowly degraded part. In conclusion, chestnut tannin is more suitable for protecting FSM from rumen degradation than heat treatment. This study provides a feasible treatment solution for applying FSM to dairy cows, which improves the soybean meal protein utilization efficiency and reduces the amount of soybean meal used.

This study aimed to determine the effects of a polyherbal mixture (PM) containing 42.3% lignans and 21.2% flavonoids on the performance, ruminal fermentation, and serum biomarkers in preweaning Holstein calves. Sixty-four neonatal calves (40.6 ± 4.3 kg BW; 48 females and 16 males) were allocated to a randomized complete block design stratified by birth weight, birth date, and sex. Starter feed was provided ad libitum from d 4 until weaning. Treatments included a control (no PM supplementation in milk) and milk combined with PM supplement at 10, 20, or 40 g/d. The results revealed that feed efficiency, body length, or heart girth did not significantly differ among treatments. However, BW, DMI, ADG, wither height, and shank circumference increased linearly with increasing PM supplementation, while diarrhea frequency decreased linearly from d 4 to 15. Ruminal ammonia-nitrogen and molar proportions of individual VFA were not significantly affected by PM supplementation, while ruminal pH and total VFA showed a linear decrease and increase with increasing PM, respectively. Similarly, serum glucose, BUN, total protein, albumin, globulin, aspartate aminotransferase, alanine aminotransferase, IL-6, and IgM were not significantly affected by PM supplementation, while triglyceride concentrations showed quadratic and cubic decreases with increasing PM. The IGF-1 concentration, total antioxidant capacity, and IL-10 concentration increased linearly, while tumor necrosis factor-α concentrations increased quadratically with increasing PM supplementation. In conclusion, PM additions improved the growth performance of preweaning Holstein calves and reduced diarrhea frequency, with PM supplementation of 40 g/d exerting the most significant effect.

BACKGROUND:Metabolic disorders in peripartum ruminants affect health and productivity, with gut microbiota playing a key role in host metabolism. Therefore, our study aimed to characterize the gut microbiota of peripartum dairy cows to better understand the relationship between metabolic phenotypes and the rumen and fecal microbiomes during the peripartum period. RESULTS:In a longitudinal study of 91 peripartum cows, we analyzed rumen and fecal microbiomes via 16S rRNA and metagenomic sequencing across six time points. By using enterotype classification, ecological model, and random forest analysis, we identified distinct deterministic succession patterns in the rumen and fecal microbiomes (rumen: rapid transition-transition-stable; hindgut: stable-transition-stable). Key microbes, such as Succiniclasticum and Bifidobacterium, were found to drive microbial succession by balancing stochastic and deterministic processes. Notably, we observed that changes in gut microbiota succession patterns significantly influenced metabolic phenotypes (e.g., serum non-esterified fatty acid, glucose, and insulin levels). Mediation analysis suggested that specific gut microbes (e.g., Prevotella sp900315525 in the rumen and Alistipes sp015059845 in the hindgut) and metabolic pathways (e.g., glucose-related pathway) were associated with host metabolic phenotypes. CONCLUSIONS:Overall, utilizing a large gut microbiome dataset and enterotype- and ecological model-based microbiome analyses, we comprehensively elucidated the succession and assembly of the gut microbiota in peripartum dairy cows. We further confirmed that changes in gut microbiota succession patterns were significantly related to the metabolic phenotypes of peripartum dairy cows. These findings provide valuable insights for developing health management strategies for peripartum ruminants.

Mid-lactation is a key stage in dairy production characterized by high milk yields and metabolic stress in cows. Dietary potassium carbonate may enhance milk quality, but its response mechanisms, particularly the link between rumen microbiome changes and production performance, remain poorly understood. To address this knowledge gap, a total of 60 multiparous Holstein cows (parity = 2.47 ± 1.06, body weight = 601 ± 25 kg, and days in milk = 127.83 ± 31.91) were divided into four groups (n = 15 cows per group) using a randomized complete block design and fed the corresponding diets for 84 days. The feed treatments were as follows: a control group (CON, basal diet), a low dose group (LD, basal diet + 250 g/d K2CO3·1.5H2O per head), a medium dose group (MD, basal diet + 500 g/d K2CO3·1.5H2O per head), and a high dose group (HD, basal diet + 750 g/d K2CO3·1.5H2O per head). The results showed that potassium carbonate supplementation significantly influenced rumen fermentation patterns, particularly by increasing acetate (P = 0.008) and isovalerate concentrations (P < 0.001). Milk fat (P = 0.004) and protein percentage (P = 0.006) exhibited the most pronounced effects in the MD group. The rumen microbiota and metabolome revealed significant alterations in microbial community structure and function. Notably, the results indicated that in the MD group, there was an increase in the abundance of Kyoto Encyclopedia of Genes and Genomes (KEGG) genes associated with crucial metabolic pathways: amino acid biosynthesis, long-chain fatty acid biosynthesis and fatty acid elongation pathways. These findings suggest that dietary supplementation with 500 g/d of potassium carbonate optimizes milk composition by modulating the rumen microbiota and associated metabolic pathways, supporting the potential for targeted nutritional strategies in dairy management.

Approximately, one-third of dairy cows suffer from postpartum diseases. Ketosis is considered an important inducer of other postpartum diseases by disrupting energy metabolism. Although the rumen microbiome may be involved in the etiology of ketosis by supplying volatile fatty acids, the rumen environmental dynamics of ketosis cows are unclear. Using multi-omics, this study aimed to elucidate changes in the rumen microbiome during parturition of ketosis cows and the association between the rumen microbiome and host energy metabolism. The study included 810 rumen content samples and 789 serum samples from day − 21 and 21 relative to calving day from 61 ketosis cows and 84 healthy cows. In ketosis cows, the rumen bacterial composition after parturition changed dramatically and needed a longer time to restore. The molar proportions of propionate were lower in ketosis cows than those in healthy cows on days 3 and 7 and negatively correlated with the serum β-hydroxybutyrate (BHBA) levels. The fermentation sub-pathway of propionate metabolism and partial glucogenic amino acid pathways were downregulated on day 3. Prevotella, UBA1066, and microbiota diversity indices regulate serum BHBA and glucose (GLU) levels via arginine, alanine, glycine, or propionate. Propionate administration to ketosis cows potentially decreased the serum BHBA concentration. Collectively, we found rumen disruption happened after calving among ketosis cows, and insufficient glycogenic substrates, such as propionate, may be related to ketosis development. The study findings have implications for the relationship between rumen microbiome dynamics and host energy metabolism, which lays the foundation for the future rumen microbiome investigation for improving postpartum management in cows.

Antibiotic resistance genes (ARGs) and virulence factor genes (VFGs) have become a global public health threat. As one of the main types of livestock, dairy cows under intensive farming practices pose a greater risk as the gastrointestinal tract of subclinically diseased cows serves as a "silent" gene reservoir. However, the distribution, transmission, and impacts of ARGs and VFGs in the gastrointestinal tract of subclinically diseased cows on human health and their own metabolism remain unclear. In this study, a nested case-control study was conducted within a prospective cohort of 211 periparturient dairy cows, collecting a total of 58 samples of rumen fluid, feces, and blood from subclinical ketosis and healthy cows. The results demonstrated that compared to healthy cows, the gastrointestinal microbiome of diseased cows contained a greater number of ARGs and VFGs exhibiting significantly increased abundance (ARGs in rumen: 30 vs 10, ARGs in feces: 66 vs 42; VFGs in rumen: 6 vs 1, VFGs in feces: 30 vs 10). Meanwhile, analysis of mobile genetic elements (MGEs) and MetaCompare2 database further indicated that the gastrointestinal microbiome of diseased cows poses a greater potential risk to human health. Additionally, specific ARGs/VFGs (e.g., FosM1) were found to be involved in the pathological process of ketosis of cow and were significantly associated with endogenous pathways such as bile acid metabolism. This highlights the important role of the ARGs-VFGs-CAZymes (Carbohydrate-active enzymes) co-occurrence network in host metabolic diseases. Our study highlights the human health risks of subclinically diseased cows as a reservoir of resistance genes, providing a theoretical basis and practical direction for improving the "One Health" prevention and control strategy.

Peripartum dairy cows commonly experience energy metabolism disorders, which lead to passive culling of postpartum cows and a decrease in milk quality. By using ketosis peripartum dairy cows as a model, this study aims to elucidate the metabolic mechanism of peripartum cows and provide a novel way for managing energy metabolic disorders. From a cohort of 211 cows, we integrated multi-omics data (metagenomics, metabolomics, and transcriptomics) to identify key microbes and then utilized an in vitro rumen fermentation simulation system and ketogenic hepatic cells to validate the potential mechanisms and the effects of postbiotics derived from key microbes. Postpartum cows with metabolic disorders compensate for glucose deficiency through mobilizing muscle proteins, which leads to marked decreases in milk protein content. Concurrently, these cows experience rumen microbiota disturbance, with marked decreases in the concentrations of volatile fatty acids and microbial protein, and the deficiency of alanine (Ala) in microbial protein is correlated with the metabolic disorder phenotype. Metagenomic binning and in vitro fermentation assays reveal that Ruminococcus_E bovis (MAG 189) is enriched in amino acid biosynthesis functions and responsible for Ala synthesis. Furthermore, transcriptomic and metabolomic analyses of the liver in metabolic disorder cows also show impaired amino acid metabolism. Supplementation with Ala can alleviate ketogenesis in liver cell models by activating the gluconeogenesis pathway. This study reveals that Ruminococcus_E bovis is associated with host energy metabolism homeostasis by supplying glucogenic precursors to the liver and suggests the use of Ala as a method for the treatment of energy metabolism disorders in peripartum cows.

Postpartum energy metabolism disorders pose a significant challenge to the health and productivity of dairy ruminants, yet their underlying pathogenesis remains poorly understood. The critical role of the gut microbiota in regulating host metabolic processes via the “gut-liver axis” has garnered increasing attention, but its specific mechanisms in dairy ruminant energy metabolism disorders are still unclear. This study uses dairy cows as a model and employs a large-scale case–control analysis to systematically investigate the pathophysiological basis of postpartum energy metabolism disorders through the lens of the “gut-liver axis.” Postpartum energy metabolism disorders in dairy cows are characterized by elevated blood β-hydroxybutyrate (BHB) and aspartate aminotransferase (AST) levels, and hepatic steatosis. A random forest model based on gut microbiota effectively predicts disease occurrence (AUC = 0.74). Multi-omics (metagenomics, metabolomics, and transcriptomics) analysis further identified key microbes, including Faecousia species (sp017465625 and sp017380435), Methanosphaera species (sp016282985), and Bifidobacterium globosum. These microbes regulate acetate concentration in the gut, which is significantly correlated with key genes in the hepatic PPAR and PI3K-AKT pathways, as well as with blood BHB levels. Primary hepatocyte culture experiments further confirmed that sodium acetate effectively inhibits hepatic fat deposition induced by mixed fatty acids through the hepatic AMPK-PPARA axis and reduces the production of BHB in the culture medium. This study demonstrates that key gut microbes and their metabolic product (acetate) inhibit the occurrence of metabolic disorders through the hepatic AMPK-PPARA axis. These findings provide new insights and potential therapeutic targets for understanding and mitigating postpartum metabolic disorders in dairy ruminants.

Scutellariae radix flavonoid extract (SFE) has been acknowledged for its antioxidant, anti-inflammatory and antimicrobial properties in enhancing gastrointestinal microbial communities and improving the host’s immunity. Nevertheless, the impacts of dietary supplementation with SFE on the gastrointestinal microbes and host metabolism in dairy cows remain uncertain. Therefore, the aim of this study was to assess the effects of dietary supplementation with SFE on the lactation performance, gastrointestinal microbes, and plasma biochemical parameters of dairy cows. Six ruminally and duodenally cannulated multiparous dairy cows were used in a crossover design over 28-d periods that included a 21-d adaptation and a 7-d sample collection period. Cows were fed a basal diet (CON group) or a basal diet supplemented with SFE at 25 g/d (SFE group). SFE supplementation tended to increase milk yield (P = 0.067) and milk urea N concentration (P = 0.079), and decreased the milk somatic cell counts (SCC, P = 0.036). Cows in the SFE group had lower plasma aspartate aminotransferase (AST), malondialdehyde (MDA), tumor necrosis factor (TNF-α), and interleukin-1β concentrations compared with the CON (P < 0.05). Meanwhile, SFE supplementation increased butyrate concentration in the rumen (P = 0.044). The microbial structure of rumen and duodenum were affected by SFE supplementation (P = 0.009 and P = 0.031; respectively), resulting in enrichment of Butyrivibrio in both parts of the SFE cows (P = 0.034 and P = 0.029; respectively). However, microbial structure and composition of feces were not affected by SFE supplementation. Overall, our study indicated that dietary supplementation with SFE could enhance lactation performance and milk quality in dairy cows by improving the gastrointestinal inner environment and health status.

ABSTRACT Hypoxia has long posed a serious threat to the health of both animals and humans, causing respiratory acidosis, metabolic disorders, systemic inflammation, oxidative stress damage, and other issues, thereby endangering life and limiting development in high-altitude areas. Gut microbiota plays a crucial role in life activities and hypoxia adaptation. We transplanted the gut microbiota from small mammals, plateau zokors (Myospalax baileyi), from the Qinghai–Tibetan plateau (3,500 m) to Sprague–Dawley (SD) rats housed in a hypobaric chamber (equivalent to 6,000 m altitude) for 30 days. The results showed that microbiota transplantation significantly reshaped the gut microbiota structure of the rats, notably increasing the abundance of short-chain fatty acid-producing bacteria Lachnospiraceae and Prevotellaceae, alleviating hypoxia and acidosis, reducing pulmonary hypertension and right ventricular hypertrophy, increasing the production of anti-inflammatory substances like indole-3-lactic acid, and reducing the generation of pro-inflammatory substances, such as histamine and uric acid. It also decreased the expression of inflammatory genes like lgE, TNFα, and IFN-γ in the lung. Fecal microbiota transplantation from plateau-specific species to low-altitude SD rats effectively altered metabolism, changed gene expression, decreased pulmonary artery pressure, and enhanced plateau adaptability. This study demonstrates the potential effectiveness of treating hypoxic pulmonary hypertension through microbiota transplantation and offers insights into improving hypoxia adaptation.IMPORTANCEWe report the beneficial effects of FMT on respiratory capacity, lung metabolism, and lung gene expression in SD rats under hypoxic conditions. We revealed the inhibitory effects of gut microbiota on lung mast cells and histamine expression under hypoxic conditions. The study demonstrated the potential effectiveness of treating HPH through FMT and offers insights into improving hypoxia adaptation.

This study investigated the effects of rumen-degradable starch (RDS) on lactation performance, gastrointestinal fermentation, and plasma metabolomics in dairy cows. Six mid-lactation cows, fitted with rumen, duodenum, and ileum cannulas, were used in a duplicated 3 × 3 Latin square design with 28-day periods. The cows were fed a low RDS (LRDS; 62.18 %), medium-RDS (MRDS; 71.25 %), or high-RDS (HRDS; 80.32 %) diet. The results showed that cows fed HRDS had diet a lower milk fat content by 14.77 % (LRDS) and 11.73 % (MRDS), while increased somatic cell count compared to the LRDS and MRDS groups (34.42 and 29.38 %, respectively). Additionally, rumen fluid pH was decreased in the HRDS group than in the MRDS and LRDS groups (7.81 and 7.08 %, respectively), while microbial protein (MCP) concentration was higher in the MRDS group. The HRDS group had lower concentrations of total volatile fatty acids (TVFA) and acetate in the ileal digesta than the LRDS group. The HRDS diet decreased neutral detergent fibre (NDF) digestibility compared with LRDS and MRDS groups (7.68 and 8.50 %, respectively), and reduced plasma concentrations of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), while increasing plasma lipopolysaccharide (LPS) and serum amyloid-A (SAA) levels. Pathway analysis revealed that starch and sucrose metabolism, galactose metabolism, and carbohydrate digestion and absorption were upregulated in the MRDS and HRDS groups. The HRDS diet had a tendency to negatively affect linoleic acid metabolism, glycerophospholipid metabolism, and alpha-linolenic acid metabolism. These findings provide insights into optimising feed efficiency and milk quality by regulating RDS levels in dairy cow diets.

Schizochytrium sp., a feed additive, positively affects the quality of animal meat. In this study, the molecular mechanisms through which dietary Schizochytrium sp. affects the meat quality characteristics of Tan lambs were investigated using transcriptomic techniques. The findings demonstrate that the lambs supplemented with Schizochytrium sp. had a larger loin eye area and a higher average daily gain and intramuscular fat content (P < 0.05). They also had lower drip loss (at 24 and 48 h) and shear force (P < 0.05). Further, 745 genes were differentially expressed between lambs supplemented with Schizochytrium and the control group. Moreover, KEGG pathway analysis showed that the ECM-receptor interaction pathway, which is related to muscle generation and intramuscular fat deposition, was significantly enriched in the lambs administered a diet containing Schizochytrium sp. Herein, we identified some pivotal genes linked to muscular system development and lipid metabolism. Thus, using Schizochytrium sp. may boost the meat quality of Tan lambs by modifying the expression of genes related to hub pathways. The results supply a new basis to determine the molecular mechanisms through which Schizochytrium sp. supplementation regulates the meat quality characteristics of sheep.

This study aimed to evaluate the effects of dietary supplementation with different types of Saccharomyces cerevisiae fermentation products (SCFP) on lactational performance, metabolism, acute phase protein response, and antioxidant capacities in dairy cows from −21 to 56 d in milk (DIM). One hundred and 80 multiparous Holstein dairy cows were blocked by parity, expected calving date, pre-trial body condition score, and previous 305-d ME yield, and then randomly assigned to 1 of 3 dietary treatments: basal diet (CON; n = 60), basal diet supplemented with 40 g/d of SCFP1 (XPC; n = 60; XPC, Diamond V, Cedar Rapids, IA), and basal diet supplemented with 19 g/d of SCFP2 (NTK; n = 60, NutriTek®, Diamond V, Cedar Rapids, IA). Blood (n = 15, 13 and 12 in the CON, XPC and NTK groups, respectively) was sampled at −7 ± 3, + 3, + 7, + 21, and + 28 d, and milk samples (n = 19, 18 and 15 in the CON, XPC and NTK groups, respectively) was sampled during 1–8 wk from a subset of cows from −21 to 56 d relative to calving. Data were analyzed using the MIXED procedure in SAS (SAS Institute Inc.). All data were subjected to repeated measures ANOVA. Dietary treatment (TRT), time, and their interaction (TRT × time) were considered as fixed effects and cow as the random effect. Cows fed XPC and NTK had greater energy-corrected milk (ECM). Supplementing NTK increased milk fat content and yield, and 3.5% fat-corrected milk (FCM) yield compared with CON. Milk urea nitrogen (MUN) was lower in XPC cows than CON. SCFP supplementation decreased plasma β-hydroxybutyrate (BHB), ceruloplasmin (CER), haptoglobin (HPT), and interleukin-1β (IL-1β) concentrations, whereas increased plasma phosphorus (P) concentrations. In addition, cows fed NTK showed lower creatinine (CR) and cortisol (COR) concentrations but increased plasma calcium (Ca) and myeloperoxidase (MPO) concentrations than those in the CON cows. In addition, cows fed NTK and XPC both had reduced plasma concentrations of serum amyloid-A (SAA) at 3 DIM of lactation compared with CON fed cows. Furthermore, SCFP cows had greater concentrations of plasma glucose (GLU) and calcium (Ca) than CON cows at 7 DIM, and greater concentrations of plasma phosphorus (P) at 21 DIM. Between different SCFP type fed groups, plasma concentrations of nonesterified fatty acids (NEFA), MDA, creatinine (CR), SAA, and HPT were lower in cows fed NTK compared with cows fed XPC at 7 DIM. Overall, our results indicate the potential benefits of supplementing SCFP in transition dairy cows by modulating immunity, liver metabolic function and supporting ECM yield. The results also suggest that NutriTek at 19 g/d appears to support the performance and health of dairy cows better compared with XPC at 40 g/d, based on improved metabolic and inflammatory status during the transition period.

Calf diarrhea causes huge economic losses to livestock due to its high incidence and mortality rates. Alkaline mineral complex water is an alkaline solution containing silicon, sodium, potassium, zinc, and germanium, and has biological benefits and therapeutic effects. This study aimed to evaluate the impact of alkaline mineral complex water supplementation on the health of calves and to investigate the effect of Alkaline mineral complex water supplementation on neonatal calf serum variables and the liver transcriptome. Sixty Holstein calves (age 1.88 ± 0.85 days, weight 36.63 ± 3.34 kg) were selected and randomly divided into two groups: the T group (treatment group with alkaline mineral complex water supplemented during the experiment) and C group (control group without alkaline mineral complex water supplementation). Alkaline mineral complex water supplementation significantly increased the body weight for calves aged 60 d and average daily gain during the experimental period (1–60 d). In addition, Alkaline mineral complex water supplementation could significantly decrease the diarrhea rate for calves aged 16–30 d, enhance the T-AOC, IgG, IGF-1, and IGFBP-2 in concentrations. The results of KEGG enrichment analysis in transcriptomics indicate that Alkaline mineral complex water supplementation inhibited the target IL-1B gene of the NF-kappa B signaling pathway of liver. Alkaline mineral complex water supplementation decreased calf diarrhea and improved partial immune function, anti-inflammatory activity, antioxidant capacity, and health of calves. Alkaline mineral complex is a candidate to replace medicated feed additives. Alkaline mineral complex waterAlkaline mineral complex waterAlkaline mineral complex waterAlkaline mineral complex waterAlkaline mineral complex waterAlkaline mineral complex waterAlkaline mineral complex water.

现代集约化养殖中为满足高产奶牛产奶的需求,通常饲喂大量高精料饲粮.然而,这些高精料饲粮的快速发酵会降低瘤胃pH,诱发亚急性瘤胃酸中毒(SARA)和肠道炎症,并会对胃肠道中微生物的分类组成和种群功能产生负面影响,进而对奶牛的生产、健康和福利产生负面影响.本文主要从SARA对奶牛胃肠道内环境和上皮细胞的影响进行介绍,详细阐述了SARA状态下奶牛瘤胃和后肠发酵模式、胃肠道微生物区系和上皮细胞屏障功能的变化,旨在为更好指导奶牛饲养提供理论依据.