The objective of this study was to assess the effect of fermented onion (FO) on the growth performance of Liangshan black sheep (LBS) and to elucidate its potential molecular mechanisms from a multi-omics perspective. A total of 20 LBS were randomly assigned to one of four groups and fed diets containing 0, 10, 20%, or 30% fermented onions, respectively. The initial and final body weights were recorded. Following the termination of the experiment, the control group and the group exhibiting the most significant increase in average daily gain (ADG) were selected for slaughter. Rumen epithelial tissue was then collected for transcriptome sequencing, while fermented and unfermented onions were collected for untargeted metabolomics. The study revealed that the supplementation of 20% FO led to a notable enhancement in the ADG of LBS, whereas the addition of 30% resulted in a growth-inhibitory effect. Metabolomic analysis revealed that the fermentation process markedly elevated the concentration of bioactive compounds in the onion, including quercetin, rutin, luteolin, myricetin, 4′-methoxyflavone and other flavonoids, as well as linoleic acid, γ-linolenic acid and diverse amino acids. Transcriptome analysis revealed 34 differentially expressed genes (DEGs), which were primarily enriched in protein-related signaling pathways, glycerolipid metabolism, and digestion and absorption-related pathways. The appropriate addition of FO has been demonstrated to promote the growth performance of LBS by increasing the concentration of bioactive substances and regulating metabolic processes and gene expression. The findings of this study provide a scientific basis for improving the growth performance of LBS and making more effective use of onion resources, and contribute new insights to the development and utilization of feeds.

Porcine proliferative enteropathy (PPE) is an infectious disease in pigs, caused by Lawsonia intracellularis (LI), affecting their intestines during growth and finishing stages, leading to higher production costs. Current detection methods for LI face two main challenges, delayed results and high costs, making them impractical for large-scale pig farming epidemiological surveys. This study developed a TaqMan-qPCR method using specific probes and primers based on the LI aspartate ammonia lyase genes from GenBank, completing detection in just 45 min. After optimizing reaction conditions, sensitivity analysis revealed that the detection limit of this method was 4.6 copies/μL targeting standard plasmids. The results of the specificity analysis showed no cross-reactivity with other common porcine pathogens, highlighting its specificity. The inter- and intra-group coefficients of variation were both <1%, indicating high reproducibility. Furthermore, the TaqMan-qPCR demonstrated 100% relative sensitivity, and a 92.50% compliance rate compared to conventional PCR, suggesting it could be a complement to the conventional PCR method. In summary, the TaqMan-qPCR method established in this study is not only suitable for epidemiological investigations and early qualitative and quantitative diagnosis of proliferative enteropathy in pigs, but it is also valuable for studying the biological characteristics of LI.

The HADHB gene encodes the beta-subunit of 3-hydroxy acyl-CoA dehydrogenase, closely related to energy metabolism, fatty acid synthesis, and catabolism. This study aimed to investigate the effect of the HADHB gene on the proliferation and differentiation of bovine preadipocytes and to gain new insights into the mechanisms of adipocyte regulation. RNA was extracted from adipose tissue of yellow cattle and the HADHB gene CDS region was cloned. Meanwhile, isolation and cultivation of preadipocytes were used for siRNA and adenovirus overexpression, quantitative real-time PCR, transcriptome sequencing, and cell proliferation and cell cycle were measured by oil red staining, CCK8 assay, and flow cytometry. Subsequently, the transcriptome data were analyzed using bioinformatics. The results showed that the HADHB gene modulates significantly the expression of critical genes involved in proliferation (CDK2 and PCNA) and differentiation (PPARγ and CEBPα), influencing preadipocyte proliferation and differentiation and altering cell cycle progression. The results of transcriptome sequencing demonstrated that the overexpression of the HADHB gene markedly altered the transcriptional profile of preadipocytes, with 170 genes exhibiting a significant increase in expression and 113 genes displaying a decrease. The HADHB gene exerts a regulatory influence on the differentiation process of precursor adipocytes by modulating the expression of key genes involved in proliferation and differentiation.These findings highlight the central role of the HADHB gene in adipocyte regulation and provide new insights into the regulatory mechanisms governing adipocyte biology.

Viral diseases that cause swine reproductive disorders pose severe threats to the global pig industry and result in enormous economic losses worldwide. The high similarity of clinical symptoms, widespread co-infections, and continuous emergence of novel pathogens urgently require rapid and accurate diagnostic strategies to support efficient disease prevention and control. This narrative review summarizes and analyzes the latest advances in diagnostic technologies for major swine reproductive viral pathogens, including Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), Classical Swine Fever Virus (CSFV), Porcine Circovirus (PCV), Pseudorabies Virus (PRV), and Porcine Parvovirus (PPV). We mainly focus on state-of-the-art diagnostic approaches centered on nucleic acid detection and serological identification. In terms of nucleic acid detection, this review elaborates on the technological evolution from conventional Polymerase Chain Reaction (PCR) to real-time quantitative PCR (qPCR) and digital PCR (dPCR), highlighting the critical value of multiplex PCR (mPCR) in differential diagnosis of swine viral diseases. Meanwhile, we summarize widely applicable isothermal amplification techniques, including Loop-Mediated Isothermal Amplification (LAMP) and Recombinase Polymerase Amplification (RPA)/Recombinase-Aided Amplification (RAA), which are highly suitable for point-of-care testing (POCT). Emerging CRISPR-Cas-based diagnostic systems for swine viral detection are also comprehensively discussed. Regarding serological detection, this article systematically reviews diverse Enzyme-Linked Immunosorbent Assay (ELISA) methods and their practical applications in serological antibody monitoring and the Differentiating Infected from Vaccinated Animals (DIVA) strategy. Furthermore, the potential application of Lateral Flow Immunoassay (LFIA) in rapid on-site screening is evaluated. This review aims to provide a comprehensive and up-to-date theoretical reference for the precise prevention and targeted control of swine reproductive viral diseases.

This study investigated the fatty acid profile of Muli yak (Bos grunniens) milk and its relationship with compositional parameters across different parities. Milk samples from second-, third-, and fourth-parity yaks were analysed for protein, fat, vitamins, minerals, and 37 fatty acids using gas chromatography. Statistical analyses included ANOVA, correlation analysis, principal component analysis (PCA), machine learning algorithms, and molecular docking. Parity significantly affected 15 components (p < 0.05), with third-parity milk showing the highest eicosapentaenoic acid (EPA, C20:5n3) and arachidonic acid (ARA, C20:4n6) concentrations. Among 134 significant correlations, calcium-ARA and ARA-EPA exhibited strong positive associations (|r| > 0.67). PCA explained 54.2% of the variance through three principal components, differentiating samples by parity. The optimal prediction models were ARA-XGBoost, EPA-Random Forest, ALA-GAM, and LA-SVM, with calcium and protein serving as key predictors. Molecular docking revealed that EPA-FABP2 had the lowest binding energy. These parity-related shifts in functional long-chain polyunsaturated fatty acids are meaningful for the nutritional value of yak milk (e.g., omega-3/omega-6 profile) and may also influence technological properties associated with milk fat composition (e.g., oxidative stability and processing behaviour), supporting parity-oriented quality evaluation and targeted utilisation of yak milk.