Background: Mucosal epithelia, including those of the oviduct, secrete antimicrobial innate immune molecules (AIIMS). These have bactericidal/bacteriostatic functions against a variety of pathogens. Among the AIIMs, sheep β-defensin-1 (SBD-1) is one of the most potent. Even though the SBD-1 is an important AIIM and it is regulated closely by estrogenic hormone, the regulation mechanism of 17β-estradiol has not been clearly established. We investigated the effects of E₂and agonist or inhibitor on ovine oviduct epithelial cells in regard to SBD-1 expression using reverse transcription quantitative PCR (RT-qPCR). In addition, three different pathways were inhibited separately or simultaneously to confirm the effect of different inhibitors in the regulation mechanism.Results: 17beta-estradiol (E₂) induced release of SBD-1 in ovine oviduct epithelial cells. SBD-1 expression was mediated through G-protein-coupled receptor 30 (GPR30) and Estrogen Receptors (ERs) activation in ovine oviduct epithelial cell. Inhibition of gene expression of protein kinase A (PKA), protein kinase C (PKC), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) led to a decreased SBD-1 expression.Conclusions: Taken together, E₂-induced up-regulation of SBD-1 expressions were GPR30-dependent during prophase and ERs-dependent during later-stage in ovine oviduct epithelial cells, and we assume that the effect was completed by the PKA, PKC, and NF-κB pathways simultaneous.

In vitro maturation (IVM) of oocytes is a pivotal step in assisted reproductive technologies for livestock. However, oxidative stress (OS) and mitochondrial dysfunction during in vitro culture often lead to oocyte aging, thereby limiting the efficiency of the technologies. To address these challenges, this study investigated the regulatory effects of 1-Palmitoyl-2-Oleoyl-sn-Glycero-3-Phosphocholine (POPC) on bovine oocyte IVM, aging, and developmental competence to determine the optimal concentration and explore underlying mechanisms. Cumulus–oocyte complexes (COCs) were collected from abattoir-derived bovine ovaries and cultured in IVM medium supplemented with 0 (control), 50, 100, 150, or 200 μmol/mL of POPC (n = 300 per group) at 38.5 °C under 5% CO₂ for 22 h. The optimal concentration was determined based on the first polar body extrusion rate, followed by in vitro fertilization (IVF), fluorescence staining, Smart-seq2 transcriptome sequencing, and quantitative PCR (qPCR) analysis. The results demonstrated that 150 μmol/mL of POPC yielded the highest maturation rate, significantly exceeding the control group (p < 0.05), and enhanced 2-4-cell cleavage rates after IVF. Furthermore, POPC markedly reduced intracellular reactive oxygen species (ROS) levels, increased glutathione (GSH) content, improved mitochondrial function, and restored normal spindle morphology. Transcriptomic analysis identified 350 upregulated and 280 downregulated differentially expressed genes (DEGs), which were enriched in pathways related to OS. qPCR validation confirmed upregulation of SIRT1/2 and BCL-2, along with downregulation of BAX and Caspase-1/3. Collectively, these findings suggest that 150 μmol/mL of POPC alleviates OS and activates the “SIRT–antioxidant–antiapoptotic” signaling axis, thereby providing valuable insights for optimizing assisted reproductive technologies in livestock.

In vitro maturation (IVM) is a critical step affecting the efficiency of bovine in vitro embryo production; however, oxidative stress during in vitro culture can impair oocyte quality and subsequent developmental competence. This study investigated the effects of cysteine supplementation on bovine oocyte IVM, redox homeostasis, mitochondrial status, and transcriptomic changes. Bovine cumulus-oocyte complexes were cultured in IVM medium supplemented with 0, 25, 50, 75, 100, or 125 μM cysteine, and 75 μM was identified as the optimal concentration. Compared with the control group, 75 μM cysteine increased the first polar body extrusion rate from approximately 78% to 81% and improved the fertilization/cleavage rate from approximately 74% to 82%. It also significantly increased the proportions of 2-cell, 4-cell, and 8-cell embryos, whereas morula and blastocyst rates were not significantly affected. At the cellular level, 75 μM cysteine significantly reduced ROS levels and increased GSH content, as indicated by changes in relative fluorescence intensity. JC-1 staining showed that the JC-1 monomer signal decreased from approximately 16.0 to 13.5, whereas the JC-1 aggregate signal increased from approximately 13.2 to 14.8, indicating improved mitochondrial membrane potential status. In addition, lipid droplet fluorescence intensity increased from approximately 11.8 to 13.4, mitochondrial fluorescence intensity increased from approximately 6.0 to 7.0, and cytoskeletal fluorescence intensity showed no significant difference between groups. Smart-seq2 transcriptomic analysis identified 1935 differentially expressed genes, including 1778 upregulated and 157 downregulated genes, which were mainly enriched in translation, ribosomal structural components, RNA binding, oxidative phosphorylation, and metabolism-related pathways. qRT-PCR further confirmed the upregulation of key genes, including NDUFS2, VDAC3, ANXA2, MTHFD1L, and SCD. Overall, 75 μM cysteine improves bovine oocyte IVM quality by enhancing antioxidant capacity, improving mitochondrial membrane potential, increasing lipid-derived energy substrate storage, and regulating genes related to energy metabolism and developmental competence.

Infectious bovine rhinotracheitis (IBR) is an acute, febrile, and contact infectious disease. Bovine infectious rhinotracheitis is endemic in China and even the world, which not only restricts the development of the cattle industry but also brings significant economic losses to farms. Infectious bovine rhinotracheitis virus (IBRV) contains 25 - 33 structural proteins, of which glycoproteins gB, gC, gD, gE, gG, gH, gI, gK, gL, and gM are the major structural glycoproteins of bovine rhinotracheitis virus, and all of these glycoproteins are interconnected with the assembly, invasion, release, and replication of the virus, and the only glycoproteins that are known to have been identified are gB, gC, gD, and gE. Therefore, this paper focuses on an overview of the four glycoproteins, gB, gC, gD, and gE, of bovine infectious rhinotracheitis virus (IBRV), with a view to providing a theoretical basis and reference for the differential diagnosis of IBR and the in-depth study of IBRV.

Polysaccharides from edible fungi are increasingly recognized as bioactive macromolecules with potential relevance to animal nutrition, intestinal health, and stress resilience. Lyophyllum decastes polysaccharides (LDPs) have recently attracted attention because of their reported immunomodulatory, antioxidant, anti-inflammatory, microbiota-modulating, and intestinal barrier-related activities. Available studies indicate that LDPs are structurally heterogeneous preparations whose biological properties are influenced by raw material source, extraction method, purification level, molecular weight distribution, monosaccharide composition, glycosidic linkage pattern, branching architecture, and associated non-polysaccharide components. Evidence from in vitro assays and rodent models suggests that selected LDP preparations may interact with innate immune signaling pathways, regulate oxidative and inflammatory responses, resist complete upper gastrointestinal digestion, undergo microbial fermentation, promote short-chain fatty acid production, alter gut microbiota composition, and improve intestinal barrier-related indices. These properties provide a biologically plausible basis for poultry-oriented investigation, particularly in broilers and laying hens exposed to heat stress, enteric challenge, intestinal dysbiosis, oxidative burden, or antibiotic-reduced production systems. However, the current evidence base remains largely pre-translational. Most findings are derived from chemical assays, macrophage models, simulated digestion, fecal fermentation, or murine disease models rather than controlled poultry trials. Therefore, LDPs should not yet be regarded as established feed additives for poultry. This review summarizes current knowledge on the extraction, structural features, biological activities, safety considerations, and translational prospects of LDPs, with emphasis on poultry nutrition. Key research priorities include standardized preparation and reporting, structure–function mapping, endotoxin and contaminant control, chicken-relevant mechanistic validation, target-animal safety assessment, dose–response feeding trials, challenge models, and evaluation of feed-scale feasibility. Overall, LDPs represent promising candidate functional materials for poultry nutrition, but their practical application requires rigorous poultry-specific validation.