1215 COLONIZATION OF KLEBSIELLA PNEUMONIA AND KLEBSIELLA OXYTOCA CONTRIBUTES TO THE UPREGULATION OF CHOLESTEROL METABOLISM IN FORMULA-FED NEONATAL MICE

Gastrointestinal Endoscopy · 2026-05-01

1215 COLONIZATION OF KLEBSIELLA PNEUMONIA AND KLEBSIELLA OXYTOCA CONTRIBUTES TO THE UPREGULATION OF CHOLESTEROL METABOLISM IN FORMULA-FED NEONATAL MICE

Gastroenterology · 2026-05-01

Rumen–Plasma–Milk Metabolomics Profiling Revealed Metabolic Alterations Associated with Milk Fat Synthesis in Chinese Holstein Cows

Animals · 2026-04-08 · 1 citations

Milk fat synthesis in dairy cows is a complex process affected by ruminal fermentation, systemic metabolism, and mammary gland activity. To explore the metabolic interplay across these systems, a multi-tissue metabolomics approach (rumen fluid, plasma, and milk) using ultra-high-performance liquid chromatography–mass spectrometry was used to identify metabolic differences between Chinese Holstein cows with high (H-MF, 5.82 ± 0.41%) and low (L-MF, 3.60 ± 0.12%) milk fat content under the same diet. The bovine mammary epithelial cells (BMECs) were also cultured to evaluate the impact of a key metabolite, malic acid (MA), on lipid metabolism. Our findings reveal distinct metabolic profiles across rumen fluid, plasma, and milk, with 96, 109, and 79 differential metabolites, respectively, between the L-MF and H-MF groups. In rumen fluid, H-MF cows showed higher levels of lauric acid and succinic acid, linked to fatty acid biosynthesis, while the L-MF cows had elevated citraconic and orotic acids, associated with amino acid metabolism and liver stress. Plasma from the H-MF cows contained higher β-hydroxybutyric acid, methionine sulfoxide, and phosphatidylcholine, supporting lipogenesis, whereas L-MF plasma showed increased 3-hydroxy-L-proline, indicating tissue catabolism. In milk, the L-MF cows had higher MA, while the H-MF cows exhibited elevated L-carnitine, linked to fatty acid β-oxidation. Metabolite trend analysis during rumen fluid–plasma–milk showed that 211 metabolites were classified into 8 profiles. Profile 1 had the largest number of metabolites whose levels were down-regulated from rumen to plasma and enriched in lipid metabolism. Profile 3 (mainly related to amino acid metabolism) and profile 4 (mainly related to energy metabolism) exhibited opposite trends from plasma to milk. In vitro, 200 μM of MA reduced the triglyceride content in BMECs and down-regulated lipogenic genes and their protein expression levels (fatty acid synthase, stearoyl-CoA desaturase and sterol regulatory element binding protein 1). These results highlight how rumen fluid, plasma, and milk metabolites collectively influence milk fat synthesis, with MA acting as a key regulator of lipid metabolism in mammary epithelial cells.

Ruminal microbiota-derived inosine alleviates metabolic disorders in dairy cows supplemented with grape seed extract

Animal nutrition · 2025-07-15 · 2 citations

Ruminal microbiota and their metabolites can shape host metabolic responses. Grape seed extract (GSE) can modulate ruminal microbiota profiles and metabolites in vitro, thus, underscoring their potential benefits on energy metabolism in dairy cows. In this study, Chinese Holstein cows were randomly divided into two groups ( n = 10 per group) with or without dietary supplementation of GSE (15 g/d per cow) from -3 to 3 wk relative to calving. The results showed that GSE supplementation led to increased fat corrected milk yield ( P = 0.003), feed efficiency ( P = 0.045) and reduced milk somatic cell count ( P = 0.031). In addition, GSE resulted in greater overall serum glucose ( P = 0.011) and lower non-esterified fatty acids ( P < 0.001), β-hydroxybutyric acid ( P = 0.002), haptoglobin ( P = 0.003), and serum amyloid A ( P = 0.008) concentrations along with lower alanine/aspartate aminotransferase activity ( P < 0.05). Compared with the control group, GSE supplementation altered the composition and metabolic profiles of ruminal microbiota ( P < 0.05), with microbiota-derived inosine being greater both in serum ( P < 0.001) and rumen fluid ( P < 0.001). In addition, ruminal inosine correlated positively with milk production and alleviation of negative energy balance ( r > 0.5, P < 0.05). Furthermore, just as GSE in vivo, exogenous inosine treatment elicited similar effects on energy metabolism and inflammation both in vitro (1 μM, hepatocytes and adipocytes) and in dairy cows with ketosis (8 mg/kg per day, n = 5) ( P < 0.05). Overall, results underscore a beneficial effect of ruminal microbiota-derived inosine in maintaining metabolic homeostasis postcalving. Thus, dietary GSE supplementation may improve energy metabolism and inflammatory state in dairy cows by enhancing ruminal-derived inosine production. Feeding GSE and inosine can be a potential strategy to alleviate health problems and optimize productivity in dairy cows during the transition period.

Prepartal dietary cobalt source alters holstein calf semitendinosus muscle abundance of mTOR and insulin signaling proteins and intermediates of one-carbon metabolism

Frontiers in Animal Science · 2025-12-03 · 1 citations

Requirement for Cobalt and folic acid (FOA) in late-pregnant dairy cows is unknown, but dietary supply of one or both could impact activity of one-carbon metabolism. Holstein cows were fed the same basal diet supplemented with Cobalt glucoheptonate (CoPro, n =16) or a slow-release Cobalt polysaccharide (CoPectin, n = 14) for the last 30 days prepartum to assess impacts on calf growth and skeletal muscle metabolism. Cobalt treatments delivered 1 ppm Cobalt/kg DM and both diets supplied 50 mg ruminally-available FOA/day. Calves were weighed at birth and growth performance recorded weekly through 9-weeks of age. Prior to weaning (day 42), calves (n = 7 and 8 for CoPro and CoPectin group, respectively) were subjected to biopsy of semitendinosus muscle for Western blotting and targeted metabolomics using LC-MS-MS. Although birth measures of development did not differ ( P &amp;gt; 0.05), calves born from CoPectin cows had greater hip width (HW) at weeks 8–9 (Diet×Time, P = 0.03). Overall, withers height (WH) tended (84.6 vs. 82.4 ± 0.9 cm; P = 0.10) to be greater in CoPectin than CoPro calves. Metabolomic profiling revealed greater concentrations of betaine (5.11 ± 0.36 × 10 6 vs. 4.12 ± 0.36 × 10 6 AUC; P = 0.04) and S-adenosylmethionine (3.87 ± 0.42 × 10 6 vs. 2.61 ± 0.42 × 10 6 AUC; P = 0.02), with tendencies for greater cystathionine (1.02 ± 0.10 × 10 6 vs. 0.71 ± 0.10 × 10 6 AUC; P = 0.06) and choline (8.04 ± 1.15 × 10 6 vs. 5.83 ± 1.15 × 10 6 AUC; P = 0.10) in CoPectin compared with CoPro calves. Protein abundance (relative to GAPDH) of INSR (1.34 ± 0.07 vs. 1.12 ± 0.05; P = 0.05), p-AKT (1.22 ± 0.08 vs. 1.01 ± 0.06; P = 0.05), and p-AKT : AKT ratio (1.37 ± 0.09 vs. 1.00 ± 0.07; P = 0.001) were greater, whereas total 4EBP1 (0.81 ± 0.06 vs. 1.03 ± 0.05; P = 0.03) and MRF4 (0.75 ± 0.05 vs. 0.96 ± 0.07; P = 0.04) were lower in CoPectin calves. These results suggest that the slow-release cobalt source (CoPectin) enhanced maternal cobalt utilization and fetal one-carbon metabolism, leading to greater activation of the insulin–AKT–mTOR pathway in calf skeletal muscle. Further research could help determine the degree to which slow-release Cobalt alters ruminal synthesis of vitamin B 12 and its impact on the physiology of the neonatal calf.

Metabolomic signatures reveal mechanisms of rumen-protected glutathione in mitigating oxidative stress and regulating inflammatory networks in transition dairy cows

Animal nutrition · 2025-08-05 · 1 citations

< 0.05). Overall, this study offers scientific evidence endorsing the application of RPG as a nutritional intervention in managing transition dairy cows.

In Vitro Three-Step Technique Assessment of a Microencapsulated Phytosynbiotic from Yanang (Tiliacora triandra) Leaf Extract Fermented with P. acidilactici V202 on Nutrient Digestibility, Cecal Fermentation, and Microbial Communities of Broilers

Veterinary Sciences · 2025-10-05 · 1 citations

The poultry industry requires sustainable strategies to improve gut health and nutrient utilization while reducing antibiotic use. This study assessed the effects of dietary supplementation with a microencapsulated phytosynbiotic from Yanang (Tiliacora triandra) leaf extract fermented with Pediococcus acidilactici V202 (YEP) on broiler ileal digestibility, microbial viability, and cecal fermentation using an in vitro gastrointestinal simulation model. Six YEP inclusion levels (0–2.5%) were tested. Results revealed significant improvements in ileal dry matter and gross energy digestibility and enhanced survival and proliferation of beneficial lactic acid bacteria in the ileum. Increased gas production, lactic acid, and volatile fatty acid concentrations, including acetate, propionate, and butyrate, indicated that cecal fermentation was enhanced in a dose-dependent manner. Moderate YEP levels optimized fermentation speed and butyrate synthesis, while higher levels enhanced total gas and acetate production. YEP also shifted the cecal microbiota toward a healthier profile, enhancing Lactobacillaceae counts and the Lactobacillaceae-to-Enterobacteriaceae ratio. Overall, protective microencapsulation, synergistic phytochemical interactions, and balanced nutrient supply had positive effects at the gut level. Thus, the data highlight YEP as a promising synbiotic feed additive that can enhance nutrient utilization, microbial balance, and gut health in broilers, warranting future in vivo validation.

Effect of substituting steam winged bean tuber for cassava chips in the diet of Holstein Friesian dairy cows

Tropical Animal Health and Production · 2025-10-13 · 1 citations

The hepatic expression status of hepatocyte nuclear factor 4α in subclinical and clinical ketotic dairy cows and its impact on lipid metabolism in hepatocytes

Journal of Dairy Science · 2025-07-18 · 2 citations

Due to sustained lipolysis, excessive nonesterified fatty acid (NEFA) concentrations are a common pathological factor of ketosis in peripartal cows. The NEFA provide an energy source to the liver during the transition period, but when in excess they can induce hepatic steatosis and liver dysfunction. In nonruminants, hepatocyte nuclear factor 4α (HNF4α) is involved in lipid metabolism processes in the liver. However, it is unclear whether HNF4α regulates hepatic lipid metabolism and function in cows with subclinical (SCK) and clinical ketosis (CK). Thus, the objective of this study was to investigate the expression status of the HNF4α in the liver of SCK and CK cows and its effects on lipid metabolism and cell function in hepatocytes. Liver and blood samples were collected from control cows (n = 15), cows with SCK (n = 15) and cows with CK (n = 15). To determine the effects of NEFA on lipid metabolism and cell function in vitro, hepatocytes isolated from calves were (1) treated with 0, 0.3, 0.6, or 1.2 mM NEFA for 12 h; (2) transfected with small interfering RNA for control (si-control) or si-HNF4A, or pCMV-EGFP or pCMV-EGFP-HNF4A for 48 h; (3) transfected with si-control or si-HNF4A, or pCMV-EGFP or pCMV-EGFP-HNF4A for 36 h, and then treated with 1.2 mM NEFA for 12 h. Results revealed that CK cows had hepatic steatosis and liver dysfunction. The protein abundance of HNF4α and its downstream targets carboxylesterase 1 (CES1) and CES2 as well as the mRNA abundance of CES1 and CES2 were upregulated in the liver of cows with SCK, but downregulated in CK cows. A dose of 1.2 mM NEFA decreased protein abundance of HNF4α, CES1, and CES2, and induced lipid accumulation and hepatocyte dysfunction. Knockdown of HNF4A decreased protein abundance of HNF4α, CES1, and CES2 and increased activities of glutamate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase in supernatant as well as decreased cell viability. The mRNA abundance of HNF4A, CES1, and CES2 was downregulated by si-HNF4A. Genes involved in fatty acid oxidation (FAO), including peroxisome proliferator-activated receptor-α (PPARA), carnitine palmitoyltransferase 1A (CPT1A), and pyruvate dehydrogenase kinase 4 (PDK4), were also downregulated due to transfection with si-HNF4A, while lipid accumulation increased. Overexpression of HNF4A increased protein abundance of HNF4α, CES1, and CES2 and upregulated mRNA abundance of HNF4A, CES1, CES2, PPARA, CPT1A, and PDK4 in hepatocytes while reducing lipid accumulation. In the presence of 1.2 mM NEFA, knockdown of HNF4A decreased whereas overexpression of HNF4A increased protein abundance of HNF4α, CES1, and CES2. Knockdown of HNF4A downregulated whereas overexpression of HNF4A upregulated mRNA abundance of CES1, CES2, PPARA, CPT1A, and PDK4. Furthermore, knockdown of HNF4A aggravated but overexpression of HNF4A alleviated NEFA-induced lipid accumulation and hepatocyte dysfunction. Overall, HNF4α accelerates the metabolism of NEFA by activating FAO, thereby alleviating steatosis, improving hepatocyte function, and inhibiting the occurrence and development of ketosis.

Extracellular vesicles in dairy cattle: research progress and prospects for practical applications

Journal of Animal Science and Biotechnology/Journal of animal science and biotechnology · 2025-08-03 · 4 citations

Intensive dairying has diminished infectious disease resistance in dairy cattle and increased the risk of disorders affecting milk quality and productive life. Development of novel health monitoring technologies, optimization of disease treatment protocols using novel biomarkers, and development of antibiotic substitutes are necessary to further enhance the productivity of dairy cattle. Extracellular vesicles (EVs) are key mediators of cellular communication and are essential for maintaining intracellular homeostasis and regulating various physiological and pathological processes. Establishing a network of mechanisms by which EVs regulate physiological processes in dairy cattle will contribute to the development of new technologies for early disease diagnosis and disease treatment. This review summarizes the molecular characterization and advances in the study of EVs in dairy cattle and focuses on the reported mechanisms of action. Prospects and limitations for the application of EVs in monitoring health status, disease treatment and assisted reproduction are discussed.