Comparative metabolome analysis of serum changes in sheep under overgrazing or light grazing conditions

Housed feeding improves rumen health by influencing the composition of the microbiota in Honghe cattle

Rumen is one of the most vital organs for the digestion of ruminants and is influenced by factors including feeding patterns and nutrition. How rumen microbiota and barrier function change are affected feeding patterns requires attention, particularly for beef cattle. In the present study, the Honghe cattle under grazing (CON group, n = 10) and housed feeding (HES group, n = 10) conditions were selected as a model of different rumen microbiota and observed for 180 days. The indicators of immunity and antioxidants in serum and rumen epithelium of cattle were measured; and the rumen microbiota were evaluated by using 16S rRNA and ITS sequencing techniques. In the present study, the concentrations of total protein, albumin and glucose in serum of Honghe cattle were significantly increased by the HES group when compared with CON group (p < 0.05). The HES group reduced the levels of complement 3, complement 4, interleukin-4, interleukin-10, interleukin-1β and tumor necrosis factor α, but increased the levels of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) (p < 0.05). We found that the HES group enhanced the levels of T-AOC and SOD in rumen epithelium (p < 0.05). Furthermore, there was a significant up-regulation of the relative mRNA expressions of ZO-1, OCC, SOD1, SOD2, Nrf2, NQO-1 and HO-1 observed in the HES group (p < 0.05). For rumen microbiota, the HES group significantly decreased alpha diversity. The core rumen bacterial communities were Bacteroidata, Firmicutes and Proteobacteria. The relative abundances of Prevotella and Ruminococcus were increased by the HES group, but norank_f_Bacteroidales_UCG-001, Rikenellaceae_RC9_gut_group and Prevotellaceae_UCG-003 were decreased (p < 0.05). Moreover, The HES group enhanced the relative abundance of Pichia, Cyllamyces, Sterigmatomyces and Wallemia (p < 0.05), but decreased Aspergillus and Candida (p < 0.05). There was a positive correlation between microorganisms such as Prevotella, Ruminococcus and Pichia and rumen epithelial barrier and antioxidant-related genes (p < 0.05). Overall, housed feeding contributed to the improvement of antioxidant capacity and rumen health in Honghe cattle, which may be related to the modulation of rumen microbiota including bacteria and fungi.

Rumenomics: Evaluation of rumen metabolites from healthy sheep identifies differentially produced metabolites across sex, age, and weight

Background

The rumen harbors a diverse and dynamic microbiome vital in digesting vegetation into metabolic byproducts for energy and general biological function. Although previous studies have reported connections between the rumen and the overall health of the sheep, the exact biological process by which this occurs is not well understood. Therefore, our study aimed to quantify sheep rumen metabolites to determine if enriched biological pathways are differentiable across phenotypic features of sex, age, and weight.

Results

We collected and quantified metabolites of rumen samples from sixteen sheep using liquid chromatography-tandem mass spectrometry. We performed a series of univariate and multivariate statistical analyses to interpret the rumen metabolomics data. To identify metabolic pathways associated with the phenotypic features of sex, weight, and age, we used MetaboAnalyst, which identified amino acid metabolism as a distinguishing factor. Among the pathways, phenylalanine metabolism emerged as a key pathway differentiating sheep based on sex and age. Additionally, phenylalanine, tyrosine, and tryptophan biosynthesis were exclusively associated with age. In univariate linear models, we also discovered that these amino acid and protein pathways were associated with weight by age-corrected effect. Finally, we identified arginine and proline biosynthesis as a pathway linked to metabolites with weight.

Conclusion

Our study identified differential pathways based on the sex, age, and weight features of sheep. Metabolites produced by the rumen may act as an indicator for sheep health and other ruminants. These findings encourage further investigation of the differentially produced metabolites to assess overall sheep health.

Morphological and physiological features in small ruminants: an adaptation strategy for survival under changing climatic conditions

Climate change due to natural human activity is a significant global phenomenon affecting the sustainability of most countries' livestock industries. Climate change factors such as ambient temperature, relative humidity, direct and indirect sun radiation, and wind have significant consequences on feed, water, pasture availability, and the re-emergence of diseases in livestock. All these variables have a considerable impact on livestock production and welfare. However, animals' ability to respond and adapt to changes in climate differs within species and breeds. Comparatively, small ruminants are more adaptive to the adverse effects of climate change than large ruminants in terms of reproduction performance, survival, production yield, and resistance to re-emerging diseases. This is mainly due to their morphological features against harsh climate effects. Tropical breeds are more adaptive to the adverse effects of climate change than small temperate ruminants. However, the difference in morphological characteristics towards adaptation to the impact of climate change will guide the development of suitable policies on the selection of breeding stock suitable for different regions in the world. The choice of breeds based on morphological features and traits is an essential strategy in mitigating and minimizing the effects of climate change on small ruminants' production and welfare. This review highlights the adaptive morphological features within and among breeds of small ruminants toward adaptation to climate change.

Self-Assembling Peptide Dendron Nanoparticles with High Stability and a Multimodal Antimicrobial Mechanism of Action

Self-assembling nanometer-scale structured peptide polymers and peptide dendrimers have shown promise in biomedical applications due to their versatile properties and easy availability. Herein, self-assembling peptide dendron nanoparticles (SPDNs) with potent antimicrobial activity against a range of bacteria were developed based on the nanoscale self-assembly of an arginine-proline repeat branched peptide dendron bearing a hexadecanoic acid chain. The SPDNs are biocompatible, and our most active peptide dendron nanoparticle, C₁₆-3RP, was found to have negligible toxicity after both in vitro and in vivo studies. Furthermore, the C₁₆-3RP nanoparticles showed excellent stability under physiological concentrations of salt ions and against serum and protease degradation, resulting in highly effective treatment in a mouse acute peritonitis model. Comprehensive analyses using a series of biofluorescence, microscopy, and transcriptome sequencing techniques revealed that C₁₆-3RP nanoparticles kill Gram-negative bacteria by increasing bacterial membrane permeability, inducing cytoplasmic membrane depolarization and drastic membrane disruption, inhibiting ribosome biogenesis, and influencing energy generation and other processes. Collectively, C₁₆-3RP nanoparticles show promising biocompatibility and in vivo therapeutic efficacy without apparent resistance development. These advancements may facilitate the development of peptide-based antibiotics in clinical settings.

Plasma metabolomic profiles as affected by diet and stress in Spanish goats

The effects of high-condensed tannin (CT) diet combined with preslaughter stress have not been studied at the metabolome level in goats. This study was conducted to determine the effects of feeding sericea lespedeza (SL; Lespedeza cuneata), a high-CT legume, and transportation stress on plasma metabolome in goats. Uncastrated male Spanish goats (age = 8 months; BW = 26.0 ± 0.48 kg) were either fed ground 'Serala' SL hay (SER), bermudagrass (Cynodon dactylon) hay (BG), or bermudagrass hay-dewormed goats (BG-DW; Control) at 75% of intake, with a corn-based supplementation (25%) for 8 weeks (n = 12/Diet). At the end of the trial, goats were subjected to one of two stress treatments (ST): transported for 90 min to impose stress (TS) or held in pens (NTS) before slaughtering, in two replicates. Live and carcass weights, and blood samples were collected at 0, 30, 60 and 90 min of transportation or holding time (Time). The data were analyzed using MIXED procedures in SAS and metabolomics data were analyzed using the R software. When measured after ST, SER group had the lowest body weight (P < 0.05) among the three diet groups. Carcass weights were high in the BG-DW, low in SER, and intermediate in BG group. Plasma creatine concentrations decreased over Time (P < 0.01) in the TS goats in all diet groups. Meat crude protein percentages were higher (P < 0.05) in SER (22.5 ± 0.22) and BG-DW (22.3 ± 0.22) groups compared to the BG group (21.6 ± 0.22). At the metabolome level, SER group had the lowest (P < 0.05) glycine, alanine, threonine, taurine, trans-hydroxyproline, methionine, and histidine concentrations and highest (P < 0.01) lysine and citrulline concentrations among the Diet groups. Butyric acid, concentration was higher (P < 0.05) in the SER group compared to BG group. Eight medium- and long-chained acylcarnitines were higher (P < 0.05) in the BG-DW group than SER or BG groups. In general, amino acid levels decreased and acylcarnitine increased with Time (P < 0.05) in all groups. Sericea diet can be beneficial in enhancing stress coping abilities in goats due to elevated butyrate, lysine, and citrulline levels; however, SER resulted in lower energy level in goats compared to BG or BG-DW groups. Fatty acid metabolism is the main energy pathway in all groups during prolonged stress. Inclusion of certain varieties of SL in the diet must be carefully controlled to prevent possible negative effect.

Methyl-Donor Micronutrient for Gestating Sows: Effects on Gut Microbiota and Metabolome in Offspring Piglets

This study aimed to investigate the effects of maternal methyl-donor micronutrient supplementation during gestation on gut microbiota and the fecal metabolic profile in offspring piglets. Forty-three Duroc × Erhualian gilts were assigned to two dietary groups during gestation: control diet (CON) and CON diet supplemented with MET (folic acid, methionine, choline, vitamin B6, and vitamin B12). The body weights of offspring piglets were recorded at birth and weaning. Besides this, fresh fecal samples of offspring piglets were collected at 7, 14, and 21 days. The gut microbiota composition, metabolic profile, and short-chain fatty acid (SCFA) profiles in the fecal samples were determined using 16S rDNA sequencing, liquid chromatography-mass spectrometry metabolomics, and gas chromatography methods, respectively. The results showed that maternal methyl-donor micronutrient supplementation increased the microbiota diversity and uniformity in feces of offspring piglets as indicated by increased Shannon and Simpson indices at 7 days, and greater Simpson, ACE, Chao1 and observed species indices at 21 days. Specifically, at the phylum level, the relative abundance of Firmicutes and the Firmicutes to Bacteroidetes ratio were elevated by maternal treatment. At the genus level, the relative abundance of SCFA-producing Dialister, Megasphaera, and Turicibacter, and lactate-producing Sharpea as well as Akkermansia, Weissella, and Pediococcus were increased in the MET group. The metabolic analyses show that maternal methyl-donor micronutrient addition increased the concentrations of individual and total SCFAs of 21-day piglets and increased metabolism mainly involving amino acids, pyrimidine, and purine biosynthesis. Collectively, maternal methyl-donor micronutrient addition altered gut microbiota and the fecal metabolic profile, resulting in an improved weaning weight of offspring piglets.