Minli Yu

Chicken flavor drives consumer preference, but mechanisms underlying flavor differences between slow-growing indigenous and fast-growing commercial broilers remain unclear. This study compares Xueshan chickens (XS) and Hubbard white broilers (HW) breast flavor via integrated sensory evaluation and multi-omics. Electronic sensory analysis showed that XS exhibited significantly higher intensities of ammonia-like and alkane aromatic odors, greater sweetness and lower flavor richness compared to HW (P < 0.05). Multi-omics analyses identified 97 differentially expressed metabolites (DEMs) and 366 differentially expressed genes (DEGs), with key enrichments in lipid metabolism (PPAR signaling pathway, fatty acid metabolism) and amino acid metabolism (lysine degradation, glycine, serine, and threonine metabolism, and sulfur metabolism). Integrated network analysis uncovered key gene-metabolite interactions: Dhcr24 was significant positively correlated with glutaric acid and palmitic acid (P < 0.05), Tnnt2, Myh1f, and Myh1b was significant negatively correlated with acetyl-CoA (P < 0.05), which collectively modulate flavor precursor synthesis. Furthermore, a Sankey diagram visually demonstrated tight molecular interactions and regulatory networks among fatty acids, DEMs and DEGs. These findings provide novel insights into the molecular basis of breed-specific flavor divergence, offering a theoretical foundation for genetic improvement and nutritional interventions to improve chicken meat quality.

The focus on selecting broilers for rapid growth rates and enhanced breast muscle yield has resulted in a decline in meat quality. The differences in carcass characteristics and meat quality between Hubbard white broilers (HWs, a commercial breed) and Xueshan chickens (XSs, an indigenous breed) at market age were analyzed to determine the potential mechanisms responsible for these differences. The results show that HWs exhibited significantly better carcass performance than XSs, including the larger weight of the carcass, the breast muscle, and the thigh muscle (p < 0.01). In addition, based on HE staining analysis, HWs’ breast muscles had a considerably larger average myofiber area and diameter than those of XSs (p < 0.01). Furthermore, the physical characteristics of the meat revealed that XSs had higher redness and yellowness and also higher lightness. HW meat had a higher pH and thermal loss, but a lower shear force and drip loss than XS meat (p < 0.01). The content of saturated fatty acids (SFAs) and polyunsaturated fatty acids (PUFAs) was, remarkably, lower in the breast muscles of HWs than of XSs (p < 0.01). In contrast, HWs had a larger concentration of monounsaturated fatty acids (MUFAs) than XSs (p < 0.01). Finally, the breast muscles of XSs had lower levels of mRNA expression for genes linked to lipid metabolism, such as fatty acid binding protein 4 (Fabp4) and peroxisome proliferator-activated receptor alpha (Pparα), and had higher levels of the phosphofructokinase muscle type (Pfkm) compared to HWs (p < 0.01). These results indicate that a lower carcass yield was observed in XSs compared with HWs, but that XSs showed better performance in terms of meat quality than HW.

Introduction: The present study aimed to evaluate the potential of antimicrobial peptide microcin J25 (MccJ25) as a feed additive for pigeons.Methods: A total of 28-day-old pigeons were allocated to four groups and fed a basal diet (CON) or a basal diet supplemented with 100, 200, or 300 mg/kg MccJ25 (ABP100, ABP200, and ABP300) for 8 weeks.Results: Dietary MccJ25 supplementation significantly improved survival rates in the ABP200 group compared to the control (p < 0.05). Serum analysis revealed that ABP200 and ABP300 groups exhibited increased levels of total protein (TP), globulin (GLB), immunoglobulin A (IgA), and immunoglobulin G (IgG), alongside reduced aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol (TC), and triglyceride (TG) concentrations (p < 0.05). Furthermore, MccJ25 supplementation enhanced duodenal maltase and trypsin activity (p < 0.05) and upregulated intestinal and hepatic antioxidant capacity, as evidenced by elevated glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activity (p < 0.05). Intestinal morphology improvements were observed in the jejunum and ileum, with increased villus height-to-crypt depth ratios (VH/CD) (p < 0.05). Additionally, ABP200 and ABP300 groups demonstrated significant upregulation of intestinal barrier-related genes occludin (OCLN), claudin 1 (CLDN1), zonula occluden protein 1 (ZO1), mucin 2 (MUC2), superoxide dismutase 1, 2 (SOD1, 2), and catalase (CAT) in duodenum (p < 0.05).Discussion: These findings indicate that MccJ25 supplementation improves systemic metabolism, enhances antioxidant defenses, strengthens intestinal barrier integrity, and ultimately promotes pigeon health and survival. This study supports the application of MccJ25 as a functional feed additive in poultry production.

Objective: The objective of this study was to identify candidate genes that play important roles in skeletal muscle development in ducks.Methods: In this study, we investigated the transcriptional sequencing of embryonic pectoral muscles from two specialized lines: Liancheng white ducks (female) and Cherry valley ducks (male) hybrid Line A (LCA) and Line C (LCC) ducks. In addition, prediction of target genes for the differentially expressed mRNAs was conducted and the enriched gene ontology (GO) terms and Kyoto encyclopedia of genes and genomes signaling pathways were further analyzed. Finally, a protein-to-protein interaction network was analyzed by using the target genes to gain insights into their potential functional association.Results: A total of 1,428 differentially expressed genes (DEGs) with 762 being up-regulated genes and 666 being down-regulated genes in pectoral muscle of LCA and LCC ducks identified by RNA-seq (p<0.05). Meanwhile, 23 GO terms in the down-regulated genes and 75 GO terms in up-regulated genes were significantly enriched (p<0.05). Furthermore, the top 5 most enriched pathways were ECM-receptor interaction, fatty acid degradation, pyruvate degradation, PPAR signaling pathway, and glycolysis/gluconeogenesis. Finally, the candidate genes including integrin b3 (Itgb3), pyruvate kinase M1/2 (Pkm), insulinlike growth factor 1 (Igf1), glucose-6-phosphate isomerase (Gpi), GABA type A receptorassociated protein-like 1 (Gabarapl1), and thyroid hormone receptor beta (Thrb) showed the most expression difference, and then were selected to verification by quantitative realtime polymerase chain reaction (qRT-PCR). The result of qRT-PCR was consistent with that of transcriptome sequencing.Conclusion: This study provided information of molecular mechanisms underlying the developmental differences in skeletal muscles between specialized duck lines.

Green eggs are mainly caused by inserting an avian endogenous retrovirus (EVA-HP) fragment into the SLCO1B3 gene. Although the genotypes for this insertion allele are consistent, eggshell color (ESC) may vary after a peak laying period; light-colored eggs are undesired by consumers and farmers and result in financial loss, so it is necessary to resolve this problem. miRNAs are small non-coding RNAs that exert essential functions in animal development and diseases. However, the regulatory miRNAs and detailed molecular mechanisms regulating eggshell greenness remain unclear. In the present study, we determined the genotype of green-eggshell hens through the detection of a homozygous allele insertion in the SLCO1B3 gene. The shell gland epithelium was obtained from green-eggshell hens that produced white and green shell eggs to perform transcriptome sequencing and investigate the important regulatory mechanisms that influence the ESC. Approximately 921 miRNAs were expressed in these two groups, which included 587 known miRNAs and 334 novel miRNAs, among which 44 were differentially expressed. There were 22 miRNAs that were significantly upregulated in the green and white groups, respectively, which targeted hundreds of genes, including KIT, HMOX2, and several solute carrier family genes. A Gene Ontology enrichment analysis of the target genes showed that the differentially expressed miRNA-targeted genes mainly belonged to the functional categories of homophilic cell adhesion, gland development, the Wnt signaling pathway, and epithelial tube morphogenesis. A KEGG enrichment analysis showed that the Hedgehog signaling pathway was significantly transformed in this study. The current study provides an overview of the miRNA expression profiles and the interaction between the miRNAs and their target genes. It provides valuable insights into the molecular mechanisms underlying green eggshell pigmentation, screening more effective hens to produce stable green eggs and obtaining higher economic benefits.