We evaluated different sample preparation methods for one‐dimensional proton nuclear magnetic resonance metabolomics analysis of beef cattle ruminal fluid and serum. After collecting and pooling samples from five bulls (all of which received the same diet and were subjected to the same management conditions), we prepared the samples with the following methods: metabolite extraction using methanol and chloroform (M + C); metabolite extraction using methanol, chloroform and acetone (M + C + A); filtering with a 3‐kDa filter; and filtering with a 2‐μm filter. We evaluated the methods based on the spectral quality, reproducibility, ease of processing, speed and relative cost. The use of 2‐μm filters did not produce good‐spectra quality for serum samples, but it was a promising method for ruminal fluid. The yields of metabolites were similar for the the solvent extractions (22 metabolites for ruminal fluid and 29 for serum samples), but lower compared with the filter methods (31 metabolites for ruminal fluid and 47 for serum samples). The filters resulted in a higher concentration of metabolites and better reproducibility. In conclusion, the 2‐μm and 3‐kDa filter methods represent a suitable way to prepare biological samples from beef cattle for nuclear magnetic resonance – based metabolomics.

Objetivo: conhecer a prevalência, classes medicamentosas e principais motivos para a prática daautomedicação entre os estudantes de ensino médio.Método: estudo transversal descritivo, com 130 estudantes de uma escola estadual do municípiode São Paulo. Utilizou-se estatística descritiva, testes paramétricos e não paramétricos para análisede dados.Resultados: as estudantes apresentaram idade entre 14 e 20 anos, 91 (70%) eram do sexo femininoe 112 (86,2%) praticaram a automedicação. Destes, 75 (67%) utilizaram para alívio de dores, 18(16,1%) referiram ter tido reações adversas e a classe medicamentosa predominante foi a dosanalgésicos com 147 (59,2%) menções. O fácil acesso do produto nas farmácias foi o principalmotivo apontado por 49 (43,7%) participantes.Conclusão: destaca-se a importância da educação como meio de levar informações aos estudantese familiares, visando desestimular a prática da automedicação nesta faixa populacional.

Background: Beef tenderness is a key quality attribute that significantly influences consumer satisfaction; however, it exhibits considerable variability due to both genetic and environmental factors. While genomic selection based on Expected Progeny Differences (EPDs) has improved the accuracy of predictions, a substantial portion of tenderness variability remains unexplained. Metabolomics has emerged as a valuable approach to address this gap, as metabolites reflect gene–environment interactions and may serve as biomarkers for complex traits such as meat tenderness. Objectives: This study aimed to integrate genomic and metabolomic data to identify genetic loci associated with serum metabolites in Nellore calves, offspring of sires with contrasting EPDs for meat tenderness. Methods: Ninety-five male calves were evaluated and divided into two groups according to the sires’ genetic merit: FA-T (favorable EPD for tenderness, n = 45) and UN-T (unfavorable EPD for tenderness, n = 46). Blood serum samples were analyzed by ¹H NMR spectroscopy to quantify 40 metabolites, and genotyping was performed using a medium-density SNP panel. Metabolite quantitative trait loci (mQTL) were identified using the MatrixEQTL package, and metabolic enrichment analysis was performed in MetaboAnalyst 6.0. Results: In the FA-T group, SNPs were associated with metabolites such as phenylalanine, tyrosine, and succinate, suggesting enhanced oxidative metabolism and preservation of proteolysis. In the UN-T group, associations of pyruvate, creatinine, and glutamine with distinct SNPs indicated greater reliance on anaerobic glycolysis and early ATP consumption, potentially impairing phosphorylation and postmortem proteolytic activity. Conclusions: These findings suggest that genetic selection for tenderness may induce early divergent metabolic profiles, likely leading to persistent differences in postmortem biochemical pathways, with important implications for meat tenderness.

Polyphenol‐based feed additives have been increasingly used in feedlot diets due to their potential to modulate rumen fermentation and systemic redox and inflammatory responses; however, mechanistic evidence at the systemic level in finishing cattle remains limited. This study evaluated the effects of a polyphenol on the serum metabolites profile of finishing beef cattle. Twenty‐four ½ Angus × ½ Nellore steers fed a high‐concentrate diet were assigned to a control diet or polyphenol mixture at 2 g/animal/day. Blood was collected on days 0 (1 day before the polyphenols supplementation), 20 and 40 after the product was added to the diet, and serum metabolites were quantified by ¹ H NMR spectroscopy. Multivariate analyses indicated no clear separation of serum metabolite profiles between treatments at either sampling time. Nevertheless, polyphenol supplementation was associated with higher glycine ( p = 0.005) and lower butyrate ( p < 0.001), with tendencies for lower 3‐hydroxybutyrate, betaine, and O‐phosphocholine ( p ≤ 0.091). From days 20 to 40, 2‐hydroxybutyrate, citrate, methylmalonate, and O‐phosphocholine decreased, whereas glycine increased ( p ≤ 0.047), and a treatment × time interaction was detected for glutamine ( p = 0.023). Pathway enrichment suggested modulation of butyrate metabolism, branched‐chain fatty acid oxidation, ketone body metabolism, mitochondrial electron transport chain, peroxisomal oxidation of phytanic acid, purine metabolism, and ammonia recycling. Supplementation did not significantly affect BW, average daily gain, or fecal consistency. Overall, polyphenol mixture induced discrete but biologically coherent serum metabolome shifts consistent with changes in energy and nitrogen handling and pathways commonly linked to oxidative and inflammatory homeostasis, despite minimal effects on growth performance.

The global seafood industry faces persistent challenges related to product quality, safety, and authenticity, driven by complex supply chains, increasing demand, and the perishable nature of aquatic products. Traditional analytical methods often fall short in providing rapid, comprehensive, and non-destructive insights into the intricate biochemical changes occurring in seafood. ¹H Nuclear Magnetic Resonance (¹H NMR) spectroscopy has emerged as a powerful and versatile tool for metabolomics, offering a holistic view of the low-molecular-mass compounds (metabolites) present in biological samples. The present study applied ¹H NMR for chemical fingerprint identification in mullets (Mugil liza) from Brazil. Dorsal muscle samples were taken from the fish during summer, autumn, and winter. The procedure involved freeze-drying the muscle tissue, thereafter extracting polar metabolites using designated solvents (methanol, water, and chloroform), and analyzing them using a 600 MHz spectrometer. As a result, 23 metabolites related to degradation biomarkers, essential metabolites, energy expenditure, and muscle structure were identified. The statistical analysis demonstrated a distinct separation between the geographical origins (RJ vs. SC), mostly influenced by variations in the concentrations of lactate, histidine, threonine, phenylalanine, and ornithine. Factors like fish size and seasonal variations did not markedly affect the overall metabolic profile, underscoring the reliability of these chemicals as stable origin indicators. The Principal Component Analysis identified two distinct groups of metabolites, establishing a profile for each geographical origin. The developed protocol can be applied to the processes of geographical identification. Thus, the ¹H NMR tool was efficient in determining metabolites that can be considered biomarkers in analyses for seafood traceability.

Background: Phytogenic feed additives are being explored as alternatives to conventional rumen modulators, yet their effects on the ruminal ecosystem remain insufficiently characterized when assessed only through conventional fermentation parameters. This study evaluated the effects of ethanolic and hydroalcoholic extracts of Urochloa brizantha on ruminal fermentation, methanogenic archaeal diversity, and the ruminal metabolome of sheep. Methods: Eight rumen-cannulated wethers were assigned to a replicated 4 × 4 Latin square design with four 28-day periods. Treatments consisted of no additive (CTL), ethanolic extract of U. brizantha (EE; 50 mL/day), hydroalcoholic extract (HE; 80 mL/day), and monensin (MON; 25 mg/day). Ruminal fluid was evaluated for fermentation traits, archaeal 16S rRNA gene diversity, and untargeted metabolomic profiles. Results: Conventional fermentation parameters and dry matter intake were largely unaffected by treatment, with only marginal shifts detected by orthogonal contrasts. Archaeal alpha diversity remained stable, although Methanimicrococcus was selectively enriched in the EE group (P = 0.012). Untargeted metabolomics revealed the clearest response: despite substantial overlap in global PCA profiles, PLS-DA showed significant temporal separation between day 0 and day 21 only in EE-treated sheep (P = 0.027). This EE-specific response was characterized by lower levels of aspartate, succinate, glutamate, phenylalanine, leucine, and choline, with an increased relative contribution of carboxylic acids. No comparable temporal discrimination was observed in CTL, HE, or MON. Conclusions: Urochloa brizantha extracts produced limited effects on conventional ruminal fermentation and methanogenic archaeal diversity. However, the ethanolic extract induced a distinct temporal metabolomic shift, suggesting a selective metabolic response that warrants further investigation.