The study goal was to determine the effects of sodium propionate (NaPr) during the postpartum period on lactation performance, milk fatty acid (FA) profile, blood metabolites, and fat mobilization.  This study selected 24 cows with the same parity (3), similar due date, and physical condition in the postpartum period and randomly allocated them into two groups.  The constituents of the two treatments were (1) a normal diet for the Control group and (2) a normal diet containing 246 g d^–1 of NaPr for the NaPr group.  This study demonstrated that supplementation of NaPr to dairy cows in the postpartum period had no significant impact on dry matter intake (DMI) and milk composition.  The milk proportions of 4:0, 8:0, 10:0, 13:0, 16:0, cis-10 15:1, cis-13, cis-16 22:2, total odd-chain FA, and de novo FA increased, and those of all remaining individual saturated fatty acids (SFA) and preformed FA decreased in cows fed NaPr vs. the Control diet.  Supplementing with NaPr significantly increased the concentrations of triglycerides (TG), glucose, and insulin in the plasma of cows.  This indicates that NaPr supplementation in the postpartum period provides energy for cows, which is beneficial for the body’s glucose and lipid balance.  The TG content, Perilipin-1 (PLIN1) protein expression, and orange-red lipid droplet deposition in adipose tissue were increased in cows fed NaPr vs. the Control diet.  The mRNA expression of ACCα and ACSS2 in adipose tissue was up-regulated, and the expression of CPT1A and CPT2 genes was down-regulated.  This indicates that dietary NaPr supplementation promotes the generation of acetyl CoA, thereby up-regulating the FA synthesis pathway and reducing FA oxidation.  In conclusion, dietary supplementation with NaPr promotes energy deposition, improves milk quality and fat accumulation, and alleviates negative energy balance (NEB) in postpartum dairy cattle.

Streptococcus suis has garnered increasing attention due to its implication in severe infections in both swine and humans, as well as its development of multidrug resistance.  The phenomenon of collateral sensitivity, whereby resistance to one antibiotic leads to increased sensitivity to another, provides new opportunities for mitigating the evolution of resistance.  In this study, we evolved resistance in S. suis to 11 clinically used antibiotics and characterized the resulting collateral sensitivity profiles, revealing a complex network of interactions.  Based on our findings, we identified dozens of such drug pairs and demonstrated collateral sensitivity to gamithromycin in ciprofloxacin-resistant S. suis both in vitro and in vivo.  Gamithromycin effectively limits the evolution of resistance and reduces the mutant selection window for ciprofloxacin-resistant S. suis strains.  Mechanistic studies indicated that the heightened sensitivity of ciprofloxacin-resistant S. suis to gamithromycin was associated with increased intracellular gamithromycin accumulation due to membrane potential alterations and reduced functions of proton motive force (PMF)-dependent efflux pumps.  Furthermore, collateral sensitivity-based treatments significantly resensitized ciprofloxacin-resistant S. suis strains to gamithromycin, resulting in superior efficacy, lower pharmacodynamic targets, and higher treatment success rates in a murine thigh infection model.  Our results indicate that gamithromycin sensitivity in S. suis is a collateral consequence of resistance to ciprofloxacin, providing valuable insight for the strategic design of collateral sensitivity-based antibiotic therapies for S. suis infections.

The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway plays a crucial role in innate immunity by inducing antiviral proteins in response to interferon signals.  Marek’s disease virus (MDV), a member of the alphaherpesvirus family, exerts potent tumorigenic and immunosuppressive effects.  Recent studies have primarily focused on the tumorigenic mechanisms of MDV, and the mechanism of immune evasion has not been fully understood.  In this study, we showed that MDV reduced the production of interferon-stimulated genes (ISGs) by inhibiting the phosphorylation and nuclear translocation of STAT1.  Using a dual-luciferase reporter system, we screened for viral proteins that significantly suppress interferon-stimulated response element (ISRE) promoter activity.  Meq overexpression markedly reduced ISRE promoter activity and ISG expression, whereas infection with Meq-deficient MDV induced higher ISG production in vitro and in vivo than infection with wild-type MDV.  Meq also inhibited the phosphorylation and nuclear translocation of STAT1.  Further experiments showed that Meq interacted with JAK1 and tyrosine kinase 2 (TYK2) and thereby inhibited JAK1–STAT1 interactions.  Meq degraded TYK2 via a caspase-mediated pathway.  The Meq-deficient MDV mutant replicated less efficiently than the wild-type MDV, both in vitro and in vivo.  Collectively, these findings demonstrate that Meq played an immunosuppressive role in MDV by attenuating the JAK–STAT signaling pathway, which facilitated escape from innate immune surveillance mechanisms.

Long-term fertilization shapes the size and community composition of the soil food web by altering resource quantity and quality.  Previous studies have examined specific components; however, comprehensive effects on the entire food web and underlying mechanisms remain unclear.  In this study, a 30-year experiment in a rice–wheat cropping system was conducted to assess the effects of chemical fertilizer (NPK), manure (M), and their combination (NPKM), with unfertilized soil as the control.  Biomass or abundance across key taxonomic and functional groups - including microorganisms, protozoa, nematodes, mites, collembolans, enchytraeids, and earthworms - was measured, and nematode ecological indices were calculated to evaluate bottom-up and top-down regulatory influences.  Results showed that long-term fertilization increased resource inputs, thereby enhancing most functional groups.  M and NPKM outperformed NPK across most groups, with relative increases compared to NPK ranging from 20.69 to 972.52% under M (average: 241.62%) and from 26.55 to 792.30% under NPKM (average: 189.02%).  However, differences between M and NPKM were not significant, as high soil fertility diminished the divergence in their effects.  Strong evidence for bottom-up control was observed, supported by positive correlations among functional groups and by increases in the enrichment index (51.27 and 28.49%) and enrichment footprint (11.80 and 47.17%) under M and NPKM relative to NPK.  Partial least squares path modeling further confirmed that bottom-up forces predominantly determined food web structure and biomass.  These findings indicate that sustained organic inputs, particularly when integrated with mineral fertilizers, effectively enhance soil food web complexity and size primarily through bottom-up regulatory mechanisms.

The temperature sensitivity (Q₁₀) of soil organic carbon (SOC) is a critical parameter in SOC response models concerning climate warming, which governs both the direction and magnitude of soil carbon-climate feedback.  However, the relative importance of soil organic compounds in the regulation of the Q₁₀ remains unclear, partly due to the relative stability of SOC compounds.  Long-term different fertilization could change the quantity and quality of soil organic compounds.  Here, a 38-year fertilization experiment combined with pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) was used to identify the effect of key soil organic compounds on the Q₁₀.  Five treatments were chosen: no fertilization (CK), nitrogen fertilization (N), N combined with phosphorus and potassium fertilization (NPK), manure (M), and NPK combined with manure (NPKM).  The results revealed that the Q₁₀ under M and NPKM were 1.59 and 1.66, respectively, which were significantly higher than those under CK (1.35), N (1.29), and NPK (1.36).  There was a positive linear relationship between the Q₁₀ and SOC (R²=0.76, P<0.01), whereby manure-enriched SOC is more vulnerable to decomposition under future warming.  Among the soil organic compounds, esters and phenols predominated, representing 30.30% and 18.83% of the composition, respectively.  Manure increased soil stable organic compounds relative to CK and chemical fertilizer.  The increased stable organic compounds under manure led to a high Q₁₀.  In addition to the positive effect of soil Alphaproteobacteria and pH on the Q₁₀, manure increased the Q₁₀ by increasing phenols and decreasing esters, whereas chemical fertilization did the opposite.  These findings first provide substantial evidence that soil organic compounds play an important role in the magnitude and mechanism of SOC response to climate change.  Manure-induced SOC, when compared to chemical fertilizers, conferred a heightened sensitivity to climate warming within agroecosystems.

Microbial necromass carbon (MNC) serves a crucial function in the formation and stabilization of soil organic carbon (SOC).  Although biochar amendment is recognized as a promising approach for enhancing SOC sequestration, its impact on MNC accumulation across the paddy soil profile remains uncertain.  Through a 4-year field experiment, this study examined the effect of biochar amendment on MNC accumulation across three soil layers (0–15, 15–30, and 30–45 cm) in a paddy soil profile by combining vertical soil profiling, microbial community dynamics, and biomarker analysis.  The results showed that biochar amendment reduced MNC by 10.5% (0–15 cm), 7.5% (15–30 cm), and 9.6% (30–45 cm), respectively, compared to the unamended control.  In the topsoil (0–15 cm), the reduction in MNC under biochar amendment was attributed to decreases in both fungal and bacterial necromass carbon (C), whereas in the subsoil (15–45 cm), it primarily resulted from the decrease in bacterial necromass C.  Biochar amendment reduced MNC content by decreasing microbial biomass and increasing nitrogen (N) acquisition enzyme activities, mainly due to a shift in the microbial community toward K-strategists and intensified microbial N limitation.  This study provides novel insights into the microbially-mediated SOC dynamics in response to biochar amendment.

Intercropping with leguminous green manure represents a sustainable approach to enhance agroecosystem resilience through improved soil fertility and resource-use efficiency.  However, the synergistic mechanisms between leguminous green manure intercropping and regulated deficit irrigation in maintaining maize yield stability and enhancing kernel profiles under arid conditions remain inadequately understood.  A three-year (2021–2023) split-plot field experiment incorporated main plots consisting of three green manure incorporation practices: full green manure incorporation (M||V-P), green manure stubble retention (M||V-R), and maize without green manure (maize sole cropping, SM); while split plots comprised three irrigation regimes: conventional (I3; 400 mm), 15% deficit (I2; 340 mm), and 30% deficit (I1; 280 mm).  The study examined maize grain yield, kernel quality (protein, fat, starch, and essential amino acid content), net photosynthetic rate (Pn) of maize, and soil nitrate-ammonium nitrogen content.  M||V-P and M||V-R increased maize grain yield compared to SM, with M||V-P producing 5.7% higher yields than M||V-R.  Notably, M||V-PI2 achieved comparable yield to M||V-PI3 while reducing irrigation by 15%, demonstrating an 18.3% yield increase over SMI3.  M||V-P and M||V-R enhanced kernel quality compared to SM, exhibiting higher protein, fat, starch, and essential amino acid content.  Decreased irrigation led to increased kernel protein content but reduced fat and starch contents.  The kernel protein content under M||V-PI2 showed no significant difference from M||V-PI1, while maintaining fat, starch, and essential amino acid content similar to M||V-PI3.  M||V-PI2 improved all kernel quality parameters relative to SMI3.  These enhancements primarily resulted from maize intercropped with leguminous green manure in combination with 15% deficit irrigation, which increased maize Pn by 14.3%, and elevated soil nitrate-ammonium nitrogen by 12.5 and 5.2%, respectively.  These findings demonstrate a scalable approach for sustainable maize production though the integration of leguminous green manure intercropping in water-limited regions.

Soil microbial response to warming may potentially contribute to the positive priming effect, i.e., accelerating the decomposition of native soil organic carbon (SOC) under the outsourced carbon (C) input.  Investigating microbiota that metabolize the outsourced C is essential to deciphering the mechanism of priming effect in response to warming and thus mitigating the SOC loss under warming climate.  In this work, we monitored the priming effect at 25°C, 35°C and 45°C over four weeks with weekly addition of 13C-glucose, and subsequently revealed microbial assemblage metabolizing glucose with the DNA stable-isotope probing (DNA-SIP) method.  Warming initially inhibited the priming effect, and decreased bacterial α-diversity, K/r-strategists ratio (K/r) and recalcitrant C/labile C gene ratio (R/L) in week 1, suggesting that at the onset of the outsourced C input, the increased proportion of r-strategists preferentially utilize the added glucose over SOC to meet their C and energy demands.  Yet, in week 4, positive priming effects were intensified by warming with up to 3.8-fold increase at 45°C.  Additionally, the primed C was positively correlated with K/r, R/L, and the abundances of chitin degradation genes in week 4.  These functions concurred with an increase in the abundance of resource-acquisition strategists such as Streptomyces affiliated to Actinobacteria under warming conditions over time.  From week 1 to 4, warming induced a distinctive change in glucose-assimilating bacterial community compositions with a particular decrease in the relative abundance of Actinobacteria while an enriched abundance of Chloroflexi.  Taken together, warming-triggered change of priming effect depended on alternation of microbiota and metabolic function over time.  These findings provide important insights of how warming mediates microbial metabolic use of fresh C and subsequent SOC mineralization, reflecting the positive feedback between soil C emission and climate warming.

The mineralization dynamics of soil organic carbon (SOC) in grasslands are crucial to terrestrial biogeochemical cycles.  However, the regulatory mechanisms underlying extracellular enzyme metabolism and microbial community structure during SOC mineralization across different carbon pools remain poorly understood.  In this study, a 553-day incubation experiment was conducted to examine temporal changes in CO₂ emissions, extracellular enzyme activities, microbial biomass, and microbial community composition in soils from both enclosed and grazed grasslands.  Using a three-pool model, SOC dynamics were quantified within active, slow, and passive carbon pools, revealing a shift in the dominance of mineralization from the active carbon pool to the passive carbon pool during the long-term carbon turnover, with differences observed across grassland management strategies.  Compared to grazed grasslands, enclosed grasslands exhibited an approximately 110% larger active carbon pool and higher initial SOC mineralization rates (significantly higher during the first 113 days), yet long-term microbial and enzymatic regulatory mechanisms - particularly shifts in microbial strategies, enzyme activity patterns, and their interactions with carbon pools - were similar across both management regimes.  The observed shifts in carbon pool dynamics were driven by enhanced microbial capacity to decompose passive carbon, associated with substantially increased oxidative enzyme production (e.g., mass-specific oxidase activity increased by 190.6% in enclosed soil and by 256.1% in grazed soil) and elevated nitrogen and phosphorus demands.  Notably, microbial communities shifted from fast-growing copiotrophic taxa (e.g., Proteobacteria, Bacteroidetes, Ascomycota) to slower-growing oligotrophic taxa (e.g., Acidobacteria, Actinobacteria, Planctomycetes, Basidiomycota), with the oligotroph-to-copiotroph ratio increasing by 55.5–62.6% for bacteria and 96.9–247.5% for fungi.  These changes were closely linked to shifts in enzyme activity profiles and stoichiometric ratios.  Overall, this study provides mechanistic insights into how microbial ecological strategies and enzyme activities interact to regulate SOC mineralization across different pools under contrasting grassland management regimes.  These findings advance our understanding of SOC turnover and improve predictive capabilities for carbon cycling, with broader implications for global climate change feedbacks.

Cropland abandonment substantially affects food security and agricultural sustainability, yet comprehensive analyses of its dynamics in rapidly developing regions remain limited.  This study examines the spatiotemporal patterns, labor migration influences, and food security implications of cropland abandonment in China from 1992 to 2022.  The results show that abandonment progressed through four phases: slow growth, rapid increase, high-level fluctuation peaking at 3.98% in 2016, and gradual decline.  The research identified three primary abandonment patterns - single long-term (≥10 years), progressive degradation, and occasional (3–9 years) - with distinct spatial distributions.  Long-term abandonment concentrates in the marginal agricultural areas of southwestern mountainous regions, while occasional abandonment predominates in the more economically developed eastern coastal areas, and progressive degradation patterns appear in transitional zones between plains and mountains.  Labor migration influenced abandonment non-linearly with distinct regional thresholds.  Short-distance (within-county) migration reduced abandonment rates, while medium-distance (within-province) migration significantly increased them.  Although 57.50% of abandonment occurred on low-suitability land, 42.50% affected high-suitability cropland, resulting in peak potential grain losses of 15.0 and 8.8 million tonnes for low and high suitability land respectively in 2010.  These findings support regionally differentiated land management strategies that integrate land suitability assessments, labor migration patterns, and local socioeconomic conditions to ensure agricultural sustainability.