Ru Jia

Cadmium (Cd) is a harmful pollutant commonly found in rivers near mining areas, which can interfere with the immune system of freshwater organisms. Furthermore, its combined exposure with pathogens exhibits synergistic toxic effects. To explore the immunotoxic mechanism of Cd and Aeromonas hydrophila on the freshwater crab Sinopotamon henanense, this study constructed a dual stress model to investigate the regulatory role of prophenoloxidase activation system (proPO-AS) and Toll pathways in Cd-mediated immunotoxicity. The results showed that Cd disrupts the Toll pathway by inhibiting ShDorsal expression and nuclear translocation, promoting ShCactus expression, and damaging the proPO-AS by affecting ShPPAE function, thereby reducing the host's sensitivity to pathogens. This study proposes for the first time the ShPPAE-ShDorsal-ShCactus axis as a functional hub connecting proPO-AS and Toll pathways, enabling a dual protection mechanism of "immediate killing + sustained defense". Under normal or low stress conditions, it is synergistically activated, while under high Cd concentrations or dual stress conditions, it transitions to dual inhibition. This provides a theoretical basis for elucidating the immune regulatory rules of aquatic organisms under combined heavy metal-pathogen stress and enriching the research on heavy metal immunotoxicity.

The high acidity, alcohol, and mycotoxin levels in distiller’s grains (DGs) limit its application in practical production. To address these issues, a new DG fermentation technique was developed in this research. Firstly, four strains were selected and the fermentation conditions were optimized to ferment the fresh DGs. When the inoculum was set at 8%, the fermentation temperature was maintained at 35 °C, the fermentation time lasted for 48 h, the bacterial mixture ratio (Bacillus subtilis ASAG 216: Lactobacillus acidophilus G1: Saccharomyces cerevisiae ANP 101: Streptococcus thermophilus EFR 046) was 1:1:2:1, and the contents of crude protein in fermented DGs (FDGs) were the highest, so we chose these fermentation conditions to ferment the DGs. In addition, under these fermentation conditions, the amino acids were significantly (p < 0.05) increased while the concentrations of crude fiber and mycotoxins contents were significantly (p < 0.05) decreased in FDGs than in DGs. Subsequently, the nutritional value of DGs and FDGs were evaluated using a two-step in vitro digestion method. The digestibility of dry matter, protein, and crude fiber increased by 16.23%, 13.54%, and 64.09%, respectively, in FDGs compared to that in DGs. Finally, laying hens were treated by adding 0%, 1%, 2%, and 4% FDG to the basal diet for 4 weeks. The results demonstrated that addition of 2% FDG in the diet could significantly (p < 0.05) increase the laying rate of hens compared to that fed the control diet, while addition of 4% FDG in the diet could remarkably (p < 0.05) reduce the rate of broken eggs compared to the other groups. There were no significant (p > 0.05) differences in other indices. These indicates that FDG has potential as a functional feed additive to enhance animal productivity.

Donkeys, as single-stomach herbivores, have a complex and diverse microbial community in their digestive tracts. The intestinal bacterial community is crucial for maintaining intestinal homeostasis, as well as the host’s overall nutrition and health. However, research on donkey gut microbes is relatively limited, particularly regarding the microbial colonization patterns in different intestinal segments of adult donkeys. Therefore, this study examined the abundance and function of microbiota across various sites of the intestinal tract (duodenum, jejunum, ileum, cecum, colon) and feces of healthy adult Dezhou male donkeys using 16S rRNA gene sequencing and PICRUSt analysis. The results indicate that donkeys have a rich gut microbial diversity and a large microbial population. No significant differences in the indices of alpha diversity were observed among the donkey’s duodenum, jejunum, ileum, cecum, colon, and feces. A Venn diagram analysis revealed the presence of both unique (Duodenum: 4645; Jejunum: 3586; Ileum: 4904; Cecum: 4253; Colon: 6135; Feces: 4885) and shared (339) ASVs among the different sections. A principal coordinate analysis (PCoA) revealed significant differences (R² = 0.2076, p < 0.007) across the six intestinal segments of the donkeys. At the phylum level, Firmicutes (63.64%), Bacteroidetes (20.72%), Verrucomicrobiota (9.16%), Patescibacteria (1.95%), Spirochaetota (1.87%), Actinobacteriota (1.13%), and Proteobacteria (0.42%) were the dominant bacteria in all samples. The Wilcoxon rank-sum test revealed significant differences in the proportions of genera among different intestinal segments. Specific genera were significantly enriched in various segments: Lachnospiraceae_UCG-008 and Sphaerochaeta in the duodenum; Christensenellaceae_R-7_group and Bacillus in the jejunum; NK4A214_group and Alloprevotella in the ileum; UCG-005 and Lactobacillus in the cecum; Clostridium_sensu_stricto_1 and Chlamydia in the colon; and Rikenellaceae_RC9_gut_group and Prevotellaceae_UCG-004 in the feces. A PICRUSt2 functional prediction analysis indicated that carbohydrate metabolism, prokaryotic cellular communities, antimicrobial drug resistance, immune diseases, membrane transport, signal transduction, and transcription exhibited significant differences among the different intestinal segments. This study provided critical primary data on the differences in donkey gut microbiota and the synergistic effects between gut microbiota and host functions. These findings can be used to assess donkey health status, improve breeding, and develop microbial additives.

BACKGROUND: This study aims to explore both the toxic effects of aflatoxins (AFs) and the protective effects of degrading enzymes (DE) on broilers exposed to AFs.RESULTS: The findings reveal that a diet contaminated with 69.15 μg kg⁻¹ of aflatoxin B₁ had significant adverse effects on broilers. Specifically, it led to a reduction in average daily gain, dressed yield percentage, half‐eviscerated yield with giblet yield percentage, eviscerated yield percentage, as well as serum superoxide dismutase (SOD), glutathione peroxidase activity and liver SOD activity (P < 0.05). Conversely, the diet increased the feed conversion ratio, liver index, serum glutamic oxaloacetic transaminase levels and malondialdehyde levels in both serum and liver (P < 0.05). Additionally, AFs disrupted the intestinal microflora significantly (P < 0.05), altering the relative abundance of Enterococcus, Lactobacillus and Escherichia in broiler jejunum. The addition of DE to AF‐contaminated feed mitigated these negative effects and reduced the residues of aflatoxin B₁, aflatoxin B₂ and aflatoxin M₁ in the liver and duodenum (P < 0.05). We also observed that broilers fed the diet pelleted at 80 °C exhibited improved dressing percentage and water holding capacity compared to those on the 75 °C diet.CONCLUSION: In summary, DE serves as an effective feed additive for mitigating AF contamination in poultry production. © 2024 Society of Chemical Industry.

Under extreme conditions, professional rally drivers will intentionally slip the wheels and use the special driving technique of "drifting" to control the vehicle and improve its safety of the vehicle. However, tire force has strong nonlinear characteristics under extreme drift conditions, and traditional tire models cannot accurately describe its characteristics. For this reason, this paper proposes a drift control algorithm based on the Neural Network (NN) tire model to improve the accuracy of vehicle drift. First, the 3-state-single-track vehicle model with the Magic formula is adopted to design the basic drift controller of the linear quadratic regulator (LQR) based on the solution of the drift equilibrium state. The controller is used to realize the drift of the vehicle and collect data to train the NN tire model. By using the NN tire model, more accurate lateral tire forces and corresponding drift equilibria states could be obtained. At the same time, the NN tire model updates the tire parameters of the LQR controller in real-time according to the vehicle state. Finally, the drift controller is verified by co-simulation with MATLAB/Simulink and CarSim, and the results show that the proposed method can significantly improve the accuracy of drift motion control.

In our previous work, a recombinant aflatoxin-degrading enzyme derived from Myxococcus fulvus (MADE) was reported. However, the low thermal stability of th