Castration alters the ileum microbiota of Holstein bulls and promotes beef flavor compounds.

BACKGROUND: In the beef industry, bull calves are usually castrated to improve flavor and meat quality; however, this can reduce their growth and slaughter performance. The gut microbiota is known to exert a significant influence on growth and slaughter performance. However, there is a paucity of research investigating the impact of castration on gut microbiota composition and its subsequent effects on slaughter performance and meat flavor. RESULT: The objective of this study was to examine the processes via which castration hinders slaughter productivity and enhances meat quality. Bull and castrated calves were maintained under the same management conditions, and at slaughter, meat quality was assessed, and ileum and epithelial tissue samples were obtained. The research employed metagenomic sequencing and non-targeted metabolomics techniques to investigate the makeup of the microbiota and identify differential metabolites. The findings of this study revealed the Carcass weight and eye muscle area /carcass weight in the bull group were significantly higher than those in the steer group. There were no significant differences in the length, width, and crypt depth of the ileum villi between the two groups. A total of 53 flavor compounds were identified in the two groups of beef, of which 16 were significantly higher in the steer group than in the bull group, and 5 were significantly higher in the bull group than in the steer group. In addition, bacteria, Eukaryota, and virus species were significantly separated between the two groups. The lipid metabolism pathways of α-linolenic acid, linoleic acid, and unsaturated fatty acids were significantly enriched in the Steers group. Compared with the steer group, the organic system pathway is significantly enriched in the bull group. The study also found that five metabolites (LPC (0:0/20:3), LPC (20:3/0:0), LPE (0:0/22:5), LPE (22:5/0:0), D-Mannosamine), and three species (s_Cloning_vector_Hsp70_LexA-HP1, s_Bacteroides_Coprophilus_CAG: 333, and s_Clostridium_nexile-CAG: 348) interfere with each other and collectively have a positive impact on the flavor compounds of beef. CONCLUSIONS: These findings provide a basic understanding that under the same management conditions, castration does indeed reduce the slaughter performance of bulls and improve the flavor of beef. Microorganisms and metabolites contribute to these changes through interactions.

Effects of one-week bilateral cerebellar iTBS on resting-state functional brain network and multi-task attentional performance in healthy individuals: A randomized, sham-controlled trial.

BACKGROUND: Cerebellar intermittent theta burst stimulation (iTBS) modulates the excitability of the cerebral cortex and may enhance attentional performance. To date, few studies have conducted iTBS on healthy subjects for one week and used electroencephalography (EEG) to investigate the effect of multiple stimulation sessions on resting-state functional brain networks and the daily stimulation effect on attentional performance. METHODS: 16 healthy subjects participated in a one-week experiment, receiving bilateral cerebellar iTBS or sham stimulation and engaging in multi-task attentional training. The primary measures were the one-week attentional performance and pre- and post-experiment resting-state EEG activities. Amplitude Envelope Correlation (AEC) was used to construct the functional connectivity in the eye-open (EO) and eye-closed (EC) phases. RESULTS: At least three sessions of iTBS were required to enhance multi-task performance significantly, whereas only one or two sessions failed to elicit the improvement. Compared with the control group, iTBS induced significant changes in PSD, AEC functional connectivity, and AEC network properties during the EO phase, while it had little effect during the EC phase. During the EO phase, the network property changes of the iTBS subject were correlated with improved attentional performance. CONCLUSION: The multi-task performance requires multiple stimulations to enhance. iTBS affects the resting-state alpha band brain activities during the EO rather than the EC phase. The AEC network properties may serve as a biomarker to assess the attentional potential of healthy subjects.

Verification of Key Target Molecules for Intramuscular Fat Deposition and Screening of SNP Sites in Sheep from Small-Tail Han Sheep Breed and Its Cross with Suffolk.

Intramuscular fat (IMF) is vital for meat tenderness and juiciness. This study aims to explore the IMF deposition mechanism and the related molecular markers in sheep. Two populations, Small-tail Han Sheep (STH) and STH × Suffolk (SFK) F1 (SFK × STH), were used as the research object. Histological staining techniques compared the differences in the longissimus dorsi muscle among populations. A combination of transcriptome sequencing and biological information analysis screened and identified IMF-related target genes. Further, sequencing technology was employed to detect SNP loci of target genes to evaluate their potential as genetic markers. Histological staining revealed that the muscle fiber gap in the SFK × STH F1 was larger and the IMF content was higher. Transcriptome analysis revealed that PIK3R1 and PPARA were candidate genes. Histological experiments revealed that the expressions of PIK3R1 mRNA and PPARA mRNA were lower in SFK × STH F1 compared with the STH. Meanwhile, PIK3R1 and PPARA proteins were located in intramuscular adipocytes and co-located with the lipid metabolism marker molecule (FASN). SNP locus analysis revealed a mutation site in exon 7 of the PIK3R1 gene, which served as a potential genetic marker for IMF deposition. This study's findings will provide a new direction for meat quality breeding in sheep.

Photoresponse of Solution-Synthesized Graphene Nanoribbon Heterojunctions on Diamond Indicating Phototunable Photodiode Polarity.

Graphene nanoribbon heterostructures and heterojunctions have attracted interest as next-generation molecular diodes with atomic precision. Their mass production via solution methods and prototypical device integration remains to be explored. Here, the bottom-up solution synthesis and characterization of liquid-phase-processable graphene nanoribbon heterostructures (GNRHs) are demonstrated. Joint photoresponsivity measurements and simulations provide evidence of the structurally defined heterostructure motif acting as a type-I heterojunction. Real-time, time-dependent density functional tight-binding simulations further reveal that the photocurrent polarity can be tuned at different excitation wavelengths. Our results introduce liquid-phase-processable, self-assembled heterojunctions for the development of nanoscale diode circuitry and adaptive hardware.

Neutrophil-targeted engineered prodrug nanoparticles for anti-inflammation.

Inflammation response is a defense to infection induced by invading pathogen or tissue injury. However, exaggerated inflammation may cause autoimmune or inflammatory disorders, such as acute respiratory distress syndrome, sepsis, stroke and rheumatoid arthritis. Anti-inflammatory agents and anti-cytokine therapy have been developed to inhibit inflammation pathways and neutralize cytokine storm, but the off-targeting delivery and damage in immune system cause systemic severe side-effect. Selective targeting, precise intracellular drug delivery and induced programed apoptosis of neutrophils may be a potential strategy to regulate the inflammatory responses for immune homeostasis. In this commentary, we summarized that the assembled engineering prodrug nanoparticles carrying doxorubicin via pH-responsive bonds that specifically target to and efficiently induce the apoptosis of activated neutrophils for anti-inflammation with high therapeutic efficacy and no systemically toxicity could be a promising strategy for neutrophil-mediated diseases.

Comparative analysis of Longissimus dorsi tissue from two sheep groups identifies differentially expressed genes related to growth, development and meat quality.

From a genetic perspective, the advantages of crossbreeding in sheep are unclear. In the present study, a comparative transcriptomic analysis was performed using Longissimus dorsi tissues from two sheep groups in order to identify differentially expressed genes (DEGs) related to growth, development and meat quality. Compared to Small Tail Han sheep, a total of 874 DEGs were identified in the crossbred sheep. Among these DEGs, 30, 116 and 32 DEGs were related to growth, development and meat quality, respectively. Seven DEGs highlighted by functional analysis as playing crucial roles in growth, development and meat quality were validated by the gene-act-network and co-expression-network. The expression levels of DEG mRNAs and proteins were further confirmed using RT-qPCR and western blot analyses. The results were consistent with the comparative transcriptome data. The data from this transcriptomic analysis will help to understand genetic heterosis and molecular-assisted breeding in sheep.

Structural Basis for Recognition of Human Enterovirus 71 by a Bivalent Broadly Neutralizing Monoclonal Antibody.

Enterovirus 71 (EV71) is the main pathogen responsible for hand, foot and mouth disease with severe neurological complications and even death in young children. We have recently identified a highly potent anti-EV71 neutralizing monoclonal antibody, termed D5. Here we investigated the structural basis for recognition of EV71 by the antibody D5. Four three-dimensional structures of EV71 particles in complex with IgG or Fab of D5 were reconstructed by cryo-electron microscopy (cryo-EM) single particle analysis all at subnanometer resolutions. The most critical EV71 mature virion-Fab structure was resolved to a resolution of 4.8 Å, which is rare in cryo-EM studies of virus-antibody complex so far. The structures reveal a bivalent binding pattern of D5 antibody across the icosahedral 2-fold axis on mature virion, suggesting that D5 binding may rigidify virions to prevent their conformational changes required for subsequent RNA release. Moreover, we also identified that the complementary determining region 3 (CDR3) of D5 heavy chain directly interacts with the extremely conserved VP1 GH-loop of EV71, which was validated by biochemical and virological assays. We further showed that D5 is indeed able to neutralize a variety of EV71 genotypes and strains. Moreover, D5 could potently confer protection in a mouse model of EV71 infection. Since the conserved VP1 GH-loop is involved in EV71 binding with its uncoating receptor, the scavenger receptor class B, member 2 (SCARB2), the broadly neutralizing ability of D5 might attribute to its inhibition of EV71 from binding SCARB2. Altogether, our results elucidate the structural basis for the binding and neutralization of EV71 by the broadly neutralizing antibody D5, thereby enhancing our understanding of antibody-based protection against EV71 infection.

Single Neutralizing Monoclonal Antibodies Targeting the VP1 GH Loop of Enterovirus 71 Inhibit both Virus Attachment and Internalization during Viral Entry.

UNLABELLED: Antibodies play a critical role in immunity against enterovirus 71 (EV71). However, how EV71-specific antibodies neutralize infections remains poorly understood. Here we report the working mechanism for a group of three monoclonal antibodies (MAbs) that potently neutralize EV71. We found that these three MAbs (termed D5, H7, and C4, respectively) recognize the same conserved neutralizing epitope within the VP1 GH loop of EV71. Single MAbs in this group, exemplified by D5, could inhibit EV71 infection in cell cultures at both the pre- and postattachment stages in a cell type-independent manner. Specifically, MAb treatment resulted in the blockade of multiple steps of EV71 entry, including virus attachment, internalization, and subsequent uncoating and RNA release. Furthermore, we show that the D5 and C4 antibodies can interfere with EV71 binding to its key receptors, including heparan sulfate, SCARB2, and PSGL-1, thus providing a possible explanation for the observed multi-inhibitory function of the MAbs. Collectively, our study unravels the mechanism of neutralization by a unique group of anti-EV71 MAbs targeting the conserved VP1 GH loop. The findings should enhance our understanding of MAb-mediated immunity against enterovirus infections and accelerate the development of MAb-based anti-EV71 therapeutic drugs. IMPORTANCE: Enterovirus 71 (EV71) is a major causative agent of hand, foot, and mouth disease (HFMD), which has caused significant morbidities and mortalities in young children. Neither a vaccine nor an antiviral drug is available. Neutralizing antibodies are major protective components in EV71 immunity. Here, we unraveled an unusual mechanism of EV71 neutralization by a group of three neutralizing monoclonal antibodies (MAbs). All of these MAbs bound the same conserved epitope located at the VP1 GH loop of EV71. Interestingly, mechanistic studies showed that single antibodies in this MAb group could block EV71 attachment and internalization during the viral entry process and interfere with EV71 binding to heparan sulfate, SCARB2, and PSGL-1 molecules, which are key receptors involved in different steps of EV71 entry. Our findings greatly enhance the understanding of the interplays among EV71, neutralizing antibodies, and host receptors, which in turn should facilitate the development of an MAb-based anti-EV71 therapy.

Chimeric virus-like particle vaccines displaying conserved enterovirus 71 epitopes elicit protective neutralizing antibodies in mice through divergent mechanisms.

Enterovirus 71 (EV71) is a major causative agent of hand, food, and mouth disease, which frequently occurs in young children. Since there are 11 subgenotypes (A, B1 to B5, and C1 to C5) within EV71, an EV71 vaccine capable of protecting against all of these subgenotypes is desirable. We report here the vaccine potential and protective mechanism of two chimeric virus-like particles (VLPs) presenting conserved neutralizing epitopes of EV71. We show that fusions of hepatitis B core antigen (HBc) with the SP55 or SP70 epitope of EV71, designated HBcSP55 and HBcSP70, respectively, can be rapidly generated and self-assembled into VLPs with the epitopes displayed on the surface. Immunization with the chimeric VLPs induced carrier- and epitope-specific antibody responses in mice. Anti-HBcSP55 and anti-HBcSP70 sera, but not anti-HBc sera, were able to neutralize in vitro multiple genotypes and strains of EV71. Importantly, passive immunization with anti-HBcSP55 or anti-HBcSP70 sera protected neonatal mice against lethal EV71 infections. Interestingly, anti-HBcSP70 sera could inhibit EV71 attachment to susceptible cells, whereas anti-HBcSP55 sera could not. However, both antisera were able to neutralize EV71 infection in vitro at the postattachment stage. The divergent mechanism of neutralization and protection conferred by anti-SP70 and anti-SP55 sera is in part attributed to their respective ability to bind authentic viral particles. Collectively, our study not only demonstrates that chimeric VLPs displaying the SP55 and SP70 epitopes are promising candidates for a broad-spectrum EV71 vaccine but also reveals distinct mechanisms of neutralization by the SP55- and SP70-targeted antibodies.

Non-extended cryoablation could be a new strategy in lung cancer management: An experiment on green fluorescent protein-labeled Lewis lung cancer-bearing mice.

Modern cryoablation has been performed in solid tumor management for more than two decades. Following the surgical spirits, it seems natural to pursue radical procedures in clinical practice, which results in unnecessary adverse effects. The attempt to use non-extended procedure made some marked achievements in practice but was criticized severely, because it was supposed to induce residual tumors, which would trigger the rapid development of cancer. Oncologists favored this procedure, however, claiming that non-extended cryoablation let lung cancer patients have higher quality of lives and longer survivals, in light of clinical observations. Therefore, this study was conducted trying to solve this controversy. In this study, fifty female C57BL/6J mice were grafted green fluorescent protein (GFP)-labeled Lewis lung cancer and randomized into two groups. The bidirectional diameters and fluorescence intensity of tumors, and the body weight of mice were recorded. Two weeks after the intervention, tumor volumes increased 20.95% in the cryoablation group, significantly different from that in the control group; the fluorescence intensity decreased 49.85% in the cryoablation group but increased 125.07% in the control group. Lung metastases could be observed in only 20% of mice in the cryosurgery group, contrasted to 64% in the control group. The non-extended lung cancer cryoablation does induce marginal tumor residuals, but will not trigger rapid tumor development. Inversely, the residual tumor cells are severely struck and the metastases are suppressed after the intervention. It could be a new strategy in lung cancer management, even for patients not in early stage.

GLB-13 is associated with oxidative stress resistance in Caenorhabditis elegans.

Globins constitute a superfamily of heme-binding proteins that is widely present in many species. There are 33 putative globins in the genome of Caenorhabditis elegans, where glb-13 is a homolog of neuroglobin (Ngb) based on sequence analysis and specific expression in neurons. Here we examined whether glb-13 as well as Ngb is also associated with resistance to reactive oxygen species (ROS) induced by paraquat. Our results showed that the mRNA level of glb-13 was significantly upregulated after paraquat exposure. Expression of a green fluorescent protein (GFP) reporter gene directed by the glb-13 promoter was increased by paraquat exposure. The mutant C. elegans strain glb-13(tm2825) was sensitive to paraquat-induced oxidative stress. Overexpression of human Ngb (hNgb) in C. elegans neuronal cells can rescue the paraquat sensitive phenotype of the mutant strain. glb-13 mutation or hNgb overexpression did not affect the expression of antioxidant enzymes such as superoxide dismutase (SOD). To examine the ROS-scavenging capabilities of hNgb and glb-13, we further examined the level of ROS in glb-13 mutant and hNgb transgenic (hNgb-Tg) worms. There was no statistical difference in ROS levels in the untreated controls; however in paraquat-treated worms, the ROS level was statistically repressed in the hNgb-Tg relative to enhanced green fluorescent protein (EGFP)-Tg worms or wildtype animals. Additionally, the ROS level of glb-13 mutant was statistically higher than the wildtype animals. Furthermore, hNgb overexpression diminished the ROS level of glb-13 mutant. In conclusion, hNgb can rescue the ROS sensitive phenotype of the glb-13 mutant strain. The protein GLB-13 seems to have an hNgb-like function, suggesting the importance of the globin protein family in maintaining the homeostasis of ROS signals. Our data provided evidence for the first time that glb-13 is associated with the resistance against oxidative stress-induced toxicity.

Genome-wide single-nucleotide polymorphism data and mitochondrial hypervariable region 1 nucleotide sequence reveal the origin of the Akhal-Teke horse.

OBJECTIVE: The study investigated the origin of the Akhal-Teke horse using genome-wide single-nucleotide polymorphism (SNP) data and mitochondrial hypervariable region 1 (HVR-1) nucleotide sequences. METHODS: Genome-wide SNP data from 22 breeds (481 horses) and mitochondrial HVR-1 sequences from 24 breeds (544 sequences) worldwide to examine the origin of the Akhal- Teke horse. The data were analyzed using principal component analysis, linkage disequilibrium analysis, neighbor-joining dendrograms, and ancestry inference to determine the population relationships, ancestral source, genetic structure, and relationships with other varieties. RESULTS: A close genetic relationship between the Akhal-Teke horse and horses from the Middle East was found. Analysis of mitochondrial HVR-1 sequences showed that there were no shared haplotypes between the Akhal-Teke and Tarpan horses, and the mitochondrial data indicated that the Akhal-Teke horse has not historically expanded its group. Ancestral inference suggested that Arabian and Caspian horses were the likely ancestors of the Akhal- Teke horse. CONCLUSION: The Akhal-Teke horse originated in the Middle East.

Unraveling the Impact of Cerebellar Stimulation on Attentional Performance: A Behavioral Study.

Attentional processes play a crucial role in our ability to perceive and respond to relevant stimuli. The cerebellum, traditionally associated with motor control, has recently garnered attention as a potential contributor to attention modulation. This study aimed to investigate the effects of cerebellar intermittent theta-burst stimulation (iTBS) on attentional performance using three behavioral tasks: dot counting, target selection, and multi-tasking. Seventeen healthy participants underwent either real or sham iTBS stimulation over seven days, and their performance on the tasks was assessed. Results revealed that dot counting performance did not significantly differ between the real and sham stimulation groups. However, notable improvements were observed over time, suggesting a learning effect. In contrast, significant effects of iTBS stimulation were found in the target selection task, with participants receiving real stimulation demonstrating enhanced discrimination between targets and distractors. Additionally, the multi-tasking task exhibited significant main effects of both iTBS stimulation and time, indicating improved performance with stimulation and progressive enhancements over the study period. These findings highlight the potential of cerebellar iTBS stimulation to enhance attentional performance in specific task domains. The significant effects observed in the target selection and multi-tasking tasks provide promising evidence for the modulatory role of the cerebellum in attention. Further investigations into the underlying mechanisms and optimal stimulation parameters are warranted to refine our understanding of how cerebellar iTBS stimulation influences attentional processes.

A retrospective analysis of the clinical efficacy of pancreatic duct stent implantation in the management of acute biliary pancreatitis requiring ERCP.

BACKGROUND: This study aimed to investigate the feasibility, effectiveness, and safety of pancreatic duct stenting in managing acute biliary pancreatitis (ABP) necessitating endoscopic retrograde cholangiopancreatography (ERCP). It further aimed to provide valuable insights for subsequent clinical diagnosis and treatment. METHODS: This research employs an observational retrospective case-control study design, encompassing patients with ABP who underwent ERCP at the hepatobiliary surgery department of the General Hospital of Ningxia Medical University between August 1, 2018, and December 31, 2020. A total of 229 cases were screened based on inclusion and exclusion criteria. Regardless of ABP severity, patients were categorized into the stent group (141) and the non-stent group (88). Changes in blood amylase (Amy), lipase (LIP), leukocyte count (WBC), total bilirubin (TBIL), alanine aminotransferase (ALT), hematocrit (HCT), and creatinine (CR) were compared between the two groups. Moreover, variables such as recovery time for oral feeding, hospitalization duration, hospitalization costs, local complications, systemic complications, and new organ failure were recorded to assess the therapeutic effect of pancreatic duct stenting. RESULTS: No significant differences were observed in gender, age, Acute Physiology and Chronic Health Evaluation (APACHE) II score, ABP severity grade, organ failure (OF), cholangitis, or biliary obstruction between the pancreatic stent and non-stent groups (P > 0.05). There was no significant difference in the incidence of complications related to acute pancreatitis between the two groups (P > 0.05). The median fasting and hospitalization times of patients in the stent group were significantly shorter than those in the non-stent group (P < 0.05). No significant differences between the groups were observed in hospitalization costs and in-hospital mortality (P > 0.05). There were no significant variations in white blood cell (WBC) count, TBIL, ALT, and creatinine (Cr) at admission, 72 h, and in the differences between the two groups (P > 0.05). The levels of Amy at admission and 72 h in the stent group were significantly higher than those in the non-stent group (P < 0.05). The differences in LIP and HCT in the stent group were considerably higher than in the non-stent group (P < 0.05). Although no significant differences were observed in mean Amy and LIP between the two groups (P > 0.05), the mean 72-h HCT in the stent group was 38.39% (95% confidence interval [CI] 37.82%-38.96%) was lower than that in the non-stent group (39.44%, 95% CI 38.70-40.17%) (P < 0.05). CONCLUSION: In the stent group, feeding time and hospital stay were significantly shorter than those in the non-stent group. No significant differences were observed between the two groups in the incidence of complications and mortality. The HCT value decreased more rapidly in the stent group. Early pancreatic stent implantation demonstrated the potential to shorten the eating and hospitalization duration of patients with ABP, facilitating their prompt recovery. TRIAL REGISTRATION: This study was registered as a single-center, retrospective case series (ChiCTR1800019734) at chictr.org.cn.

Effects of Oregano Essential Oil on IgA+, IgG+, and IgM+ Cells in the Jejunum of Castrated Holstein Bulls.

The aim of this study was to investigate the effect of oregano essential oil on IgA+, IgG+, and IgM+ cells in the jejunum of castrated Holstein bulls. Twelve castrated Holstein bulls were randomly divided into control (YCK) and oregano essential oil (YEO) groups. Pathological changes in the jejunum were observed by HE staining, and the expression levels of IgA, IgG, and IgM in the jejunum were detected by ELISA. The distributions of IgA+, IgG+, and IgM+ cells in the jejunum were analysed by multiplex immunofluorescence and immunohistochemistry. The results showed that the jejunal villi were detached in the YCK group, which may have been related to inflammation, while the intestinal epithelium was clear and intact in the YEO group. The expressions of IgA, IgG, and IgM were significantly reduced by 40.75%, 30.76%, and 50.87%. The IgA+, IgG+, and IgM+ cells were diffusely distributed in the lamina propria of the jejunum, and were reduced by 17.07%, 6.44%, and 6.15%, respectively. Oregano essential oil did not alter the distribution characteristics of IgA+, IgG+, or IgM+ cells in the jejunum, but it suppressed inflammatory response, decreased immunoglobulin content, and significantly enhanced the formation of an immune barrier in the gastrointestinal mucosa.

Oregano essential oil modulates colonic homeostasis and intestinal barrier function in fattening bulls.

Oregano essential oil (OEO) primarily contains phenolic compounds and can serve as a dietary supplement for fattening bulls. However, the precise molecular mechanism underlying this phenomenon remains largely elusive. Therefore, this study investigated the impact of adding OEO to diet on the integrity of the intestinal barrier, composition of the colonic microbiome, and production of microbial metabolites in fattening bulls. Our goal was to provide insights into the utilization of plant essential oil products in promoting gastrointestinal health and welfare in animals. We employed amplicon sequencing and metabolome sequencing techniques to investigate how dietary supplementation with OEO impacted the intestinal barrier function in bulls. The inclusion of OEO in the diet resulted in several notable effects on the colon of fattening bulls. These effects included an increase in the muscle thickness of the colon, goblet cell number, short-chain fatty acid concentrations, digestive enzyme activity, relative mRNA expression of intestinal barrier-related genes, and relative expression of the anti-inflammatory factor IL-10. Additionally, α-amylase activity and the relative mRNA expression of proinflammatory cytokines decreased. Moreover, dietary OEO supplementation increased the abundance of intestinal Bacteroides, Coprobacillus, Lachnospiraceae_UCG_001, and Faecalitalea. Metabolomic analysis indicated that OEO primarily increased the levels of 5-aminovaleric acid, 3-methoxysalicylic acid, and creatinine. In contrast, the levels of maltose, lactulose, lactose, and D-trehalose decreased. Correlation analysis showed that altered colonic microbes and metabolites affected intestinal barrier function. Taken together, these results demonstrate that OEO facilitates internal intestinal environmental homeostasis by promoting the growth of beneficial bacteria while inhibiting harmful ones.

Antimicrobial peptides act on the rumen microbiome and metabolome affecting the performance of castrated bulls.

BACKGROUND: Many countries have already banned the use of antibiotics in animal husbandry, making it extremely difficult to maintain animal health in livestock breeding. In the livestock industry, there is an urgent need to develop alternatives to antibiotics which will not lead to drug resistance on prolonged use. In this study, eighteen castrated bulls were randomly divided into two groups. The control group (CK) was fed the basal diet, while the antimicrobial peptide group (AP) was fed the basal diet supplemented with 8 g of antimicrobial peptides in the basal diet for the experimental period of 270 d. They were then slaughtered to measure production performance, and the ruminal contents were isolated for metagenomic and metabolome sequencing analysis. RESULT: The results showed that antimicrobial peptides could improve the daily weight, carcass weight, and net meat weight of the experimental animals. Additionally, the rumen papillae diameter and the micropapillary density in the AP were significantly greater than those in the CK. Furthermore, the determination of digestive enzymes and fermentation parameters showed that the contents of protease, xylanase, and ß-glucoside in the AP were greater than those in the CK. However, lipase content in the CK was greater than that in the AP. Moreover, the content of acetate, propionate, butyrate, and valerate was found to be greater in AP than those in CK. The metagenomic analysis annotated 1993 differential microorganisms at the species level. The KEGG enrichment of these microorganisms revealed that the enrichment of drug resistance-related pathways was dramatically decreased in the AP, whereas the enrichment of immune-related pathways was significantly increased. There was also a significant reduction in the types of viruses in the AP. 187 probiotics with significant differences were found, 135 of which were higher in AP than in CK. It was also found that the antimicrobial mechanism of the antimicrobial peptides was quite specific. Seven low-abundance microorganisms (Acinetobacter_sp._Ac_1271, Aequorivita soesokkakensis, Bacillus lacisalsi, Haloferax larsenii, Lysinibacillus_sp._3DF0063, Parabacteroides_sp._2_1_7, Streptomyces_sp._So13.3) were found to regulate growth performance of the bull negatively. Metabolome analysis identified 45 differentially differential metabolites that significantly different between the CK and the AP groups. Seven upregulated metabolites (4-pyridoxic acid, Ala-Phe, 3-ureidopropionate, hippuric acid, terephthalic acid, L-alanine, uridine 5-monophosphate) improve the growth performance of the experimental animals. To detect the interactions between the rumen microbiome and metabolism, we associated the rumen microbiome with the metabolome and found that negative regulation between the above 7 microorganisms and 7 metabolites. CONCLUSIONS: This study shows that antimicrobial peptides can improve the growth performance of animals while resisting viruses and harmful bacteria and are expected to become healthy alternatives to antibiotics. We demonstrated a new antimicrobial peptides pharmacological model. We demonstrated low-abundance microorganisms may play a role by regulating the content of metabolites.

Dietary oregano essential oil supplementation alters meat quality, oxidative stability, and fatty acid profiles of beef cattle.

This study was conducted to elucidate the effects of oregano essential oil (OEO) supplementation on the meat quality, antioxidant capacity, and nutritional value of the longissimus thoracis muscle in steers. Steers were divided into three groups (n = 9) and fed either a basal diet, or a basal diet supplemented with 130 mg/d OEO, or 230 mg/d OEO for 390 days. The results demonstrated that dietary OEO supplementation increased the total antioxidant capacity and activity of catalase, glutathione peroxidase, and superoxide dismutase, and decreased pH30min, pH24h, cooking loss, and malondialdehyde content. OEO increased the concentrations of polyunsaturated fatty acids and conjugated linoleic acid. In contrast, saturated fatty acids decreased, accompanied by increased essential amino acids, flavor amino acids, and total amino acids in the longissimus thoracis muscle. In summary, dietary OEO supplementation promotes the nutritional and meat quality of beef by maintaining its water-holding capacity and meat color, enhancing its antioxidative capacity, and preventing lipid oxidation.

Research on Price Influencing Factors of Third-Party Payment Platforms: An Empirical Study From China.

In this article, we use the two-sided market theory as a support and take the operating data of eight Chinese third-party payment platform companies as samples, based on pricing models and multiple regression analysis, to build a price feature model for a third-party payment platform. The results show that under the two-sided market environment, the scale of consumer and the same-side network externality of the merchant have a negative significant effect on the pricing of the third-party payment platform to the seller; The market share of the platform and the bank fee cost of the platform have a positive significant effect on the pricing of a third-party payment platform to the merchant. At the same time, the same-side network externality of the seller, the scale of a merchant, and the selection of the business model of the platform have no significant effect on the pricing of the third-party payment platform to the merchant. These conclusions provide a scientific basis for a third-party payment platform enterprise to develop an appropriate pricing strategy and operating model.

Screening of Genes Related to Growth, Development and Meat Quality of Sahan Crossbred F1 Sheep Based on RNA-Seq Technology.

This study aimed to identify genes related to sheep growth, development and meat quality. Small-tailed Han sheep (STH), and small-tailed Han sheep and Suffolk crossbred F1 (STH×SFK), were selected to determine the growth performance, slaughter performance, and meat quality. The longissimus dorsi muscle was selected for transcriptome sequencing, and the target gene was screened based on bioinformatics analysis; real-time fluorescent quantitative PCR (RT-PCR) and western blotting (WB) were conducted to verify the target gene. Locations of genes in tissues were confirmed via immunofluorescence. The results showed that the pre-slaughter live weight, bust circumference, slaughter performance, and marbling score of the STH×SFK population were significantly higher than those of the STH population (P < 0.01). Sequencing results showed that 560 differentially expressed genes (DEGs) were identified in the STH×SFK population, of which 377 exhibited up-regulated and 183 exhibited down-regulated expression levels. GO annotation revealed that DEGs could be classified into 13 cell components, 10 molecular functions, and 22 biological processes. The KEGG enrichment analysis showed that DEGs were mainly enriched in the Rap1 signaling pathway, Ras signaling pathway, and other pathways related to growth and meat quality. Based on the GO and KEGG analyses, four candidate genes related to sheep growth and meat quality, namely myostain (MSTN), interferon-related developmental regulator 1 (IFRD1), peroxisome proliferator activator receptor delta (PPARD), and myosin light chain 2 (MLC2 or MYL2), were screened. The expression levels of genes and proteins were verified via RT-PCR and WB, and the results were consistent with the trend of transcriptome sequencing. Immunofluorescence results showed that IFRD1 was expressed in the cytoplasm and nucleus, and MYL2 was expressed in the cytoplasm. This study revealed the mechanism of gene regulation of sheep growth and development at the molecular level and provided a theoretical basis for studying sheep genetics and breeding.