Project description:The processing ability of chicken meat is highly related to its ultimate pH (pHu), which is mainly determined by the amount of glycogen in the muscle at death. The molecular mechanisms involved in variations of those traits for chicken remain to be fully described. For that purpose, two chicken lines were divergently selected on breast meat pHu, i.e. the pHu- and the pHu+ lines. In this study, Chicken Genome Arrays (60 K) were used to compare muscle gene expression profiles of chickens from both lines. The final goal of this experiment is to identify biomarkers of low and high-pHu chicken meat. This study was supported by INRA and the French Ministry of Agriculture through the RFI CASDAR #1309 OPTIVIANDE.
Project description:Improvement of feed efficiency would increase profitability of the poultry industries by decreasing the amount of feed required for production. Korat (KR) chicken is a new alternative meat-type chicken breed which its meat is recognized for its high protein, low fat and low purine content, whereas its low feed efficiency leads to high cost of production. Deeper understanding on how feed efficiency influences meat quality is poorly elucidated. To fulfill deeper understand molecular key that point the variation in feed efficiency and meat quality, the aim of this study was to investigate molecular pathways and genes involved in feed efficiency and meat quality in thigh of slow-growing KR chicken. A total of 75 males KR chicken were reared in individual cage until 10 weeks of age. Individual feed intake and body weight were collected weekly to calculate Feed Conversion Ratio (FCR) and Residual Feed Intake (RFI). Meat quality parameters were measured in thigh muscles such as ultimate pH (pHu), water-holding capacity (WHC), drip loss (DL), nucleotides content and several biomolecules (amide, …). Base on extreme values of FCR at 10 weeks of ages, 12 birds from the high FCR group (HFCR) and 9 birds from the low FCR group (LFCR) were selected for investigating their transcriptome using an 8×60K Agilent chicken microarray. In addition, a weighted gene coexpression network analysis was performed to detect the relationship between modules of co-expressed genes and feed efficiency, meat quality in thigh muscle. The result in this study indicated that selection on feed efficiency (FCR, RFI) would affect flavor precursor, lipid and protein content in thigh muscle. Based on WGCNA and functional enrichment analysis, results suggested that the key molecular pathways relate to FCR, RFI and meat quality (WHC, DL, IMP, AMP and inosine) in thigh muscle were the pathways of regulation of biological process, biological regulation and regulation of metabolic. Moreover, we revealed four genes there are assembly competence domain (ACD) gene, baculoviral IAP repeat containing 5 (BIRC5) gene, cytochrome c oxidase assembly factor 3 (COA3) gene and myosin light chain 9 (MYL9) gene that might be biomarker gene in feed efficiency and meat quality in thigh muscle. The hypothesis of the current study was alteration feed efficiency in slow-growing chicken will impact meat quality especially in term of texture and flavor.
Project description:The aim of this study was to identify genes involved in the variation of the muscle glycogen content at death (estimated through the glycolytic potential, GP), a determining factor of meat quality in chicken. Gene expression profiles of Pectoralis major muscle were established using microarrays. We compared Fat and Lean chickens issued from two lines divergently selected for abdominal fatness and also differed for muscle GP. A total of 197 genes were differentially expressed between Fat and Lean pure chickens. Several of these genes were validated by qRT-PCR. For the genes with human orthologs, annotation analyses were performed and mainly revealed pathways involved carbohydrate, fatty-acid, and protein metabolism. The relationship between gene expression and meat quality has to now be validated by further e-QTL studies on the F2 population. 8 samples from Fat chickens were compared to 8 samples from Lean chickens, 4 of these were dye-swapped.
Project description:The aim of this study was to identify genes involved in the variation of the muscle glycogen content at death (estimated through the glycolytic potential, GP), a determining factor of meat quality in chicken. Gene expression profiles of Pectoralis major muscle were established using microarrays. We compared Fat and Lean chickens issued from two lines divergently selected for abdominal fatness and also differed for muscle GP. A total of 197 genes were differentially expressed between Fat and Lean pure chickens. Several of these genes were validated by qRT-PCR. For the genes with human orthologs, annotation analyses were performed and mainly revealed pathways involved carbohydrate, fatty-acid, and protein metabolism. The relationship between gene expression and meat quality has to now be validated by further e-QTL studies on the F2 population.
Project description:This study investigates the impact of stress on muscle physiology and meat quality in broiler chickens by comparing protein expression profiles between organic and conventional farming systems using label-free quantitative (LFQ) proteomics. Muscle samples were analyzed via nanoLC-ESI-MS/MS coupled with comprehensive bioinformatics to identify differences in protein abundance associated with rearing conditions.A total of 7,221 proteins were identified, with 1,645 proteins upregulated and 1,612 downregulated in organic chickens compared to conventional ones. Functional analyses including Gene Ontology (GO) and STRING network analyses revealed that proteins upregulated in organic chickens were predominantly involved in oxygen transport, oxygen binding, and muscle structural organization, indicating enhanced oxygen metabolism and muscle development consistent with improved animal welfare. Conversely, proteins related to ribosomal function and RNA binding were enriched in conventional chickens, suggesting stress-related alterations in protein synthesis. KEGG pathway analysis showed significant enrichment of carbon metabolism, amino acid biosynthesis, nitrogen metabolism, and the tricarboxylic acid (TCA) cycle pathways in organic chickens, while glycolysis, gluconeogenesis, and ribosomal pathways were downregulated. Key differentially expressed proteins identified as potential biomarkers distinguishing organic from conventional meat include downregulated PGM1, AMPD1, LDHA, ENO3, and PKLR, and upregulated COL1A1, COL1A2, TTN, TPM2, CA3, MB, HSPB1, ACO2, ACAA2, and TF. These proteins are involved in muscle structure and energy metabolism and may serve as indicators of meat quality linked to stress and welfare conditions. Overall, this proteomic analysis provides novel insights into how stress modulates the muscle proteome in broiler chickens and supports the adoption of welfare-focused organic poultry production practices to improve meat quality.
Project description:In the modern chicken industry, fast-growing broilers have undergone strong artificial selection for muscle growth, which has led to remarkable phenotypic variations compared with slow-growing chickens. However, the molecular mechanism underlying these phenotypes differences remains unknown. In this study, a systematic identification of candidate genes and new pathways related to myofiber development and composition in chicken Soleus muscle has been made using gene expression profiles of two distinct breeds: Qingyuan partridge (QY), a slow-growing Chinese breed possessing high meat quality and Cobb 500 (CB), a commercial fast-growing broiler line. Agilent cDNA microarray analyses were conducted to determine gene expression profiles of soleus and extensor digitorum longus muscle sampled at sexual maturity age of QY (112 d) and CB (42 d).
Project description:This project aimed to compare the proteomic profiles between conventional chicken meat and cultured chicken meat produced through cell culture techniques. Proteins were extracted, separated using SDS-PAGE and two-dimensional gel electrophoresis (2-DE), and identified through mass spectrometry. KEGG pathway enrichment and STRING-based protein-protein interaction network analyses were performed to evaluate metabolic characteristics and structural differences between the groups. Conventional meat exhibited a high abundance of glycolytic and muscle contraction-associated proteins, while cultured meat showed elevated expression of proteins involved in stress response and redox regulation. These datasets provide fundamental insights for improving the quality and ensuring the safety of cultured meat products.
Project description:Carnosine is a bioactive food component with several potential health benefits for humans due to its physiological functions. Dietary supplementation with β-alanine or L-histidine can increase the carnosine content of skeletal muscles in chickens. Dietary supplementation with β-alanine or L-histidine has produced a slow-growing chicken variety with high carnosine content in the breast meat; however, the supplementation with L-histidine alone softens the meat toughness, which may affect consumers’ willingness to buy the meat. Gene expression is a key factor that influences meat quality. Understanding the molecular mechanisms that affect carnosine content and meat toughness would allow the production of more value-added slow-growing chickens. We compared global gene expression in chicken breast muscles with differing carnosine contents and meat toughness produced through dietary supplementation with β-alanine or L-histidine. We identified differentially expressed genes involved in regulating myosin, collagen, intramuscular fat, and calpain—factors that may affect meat tenderness. Pathway enrichment analysis indicated that the insulin-related and adipocytokine signaling pathways were altered by dietary supplementation with β-alanine or L-histidine. These data will be useful for future studies on carnosine content and meat toughness in slow-growing chickens.
Project description:Chronological age is one of the important factors influencing muscle development and meat quality in chickens. To evaluate the protein expression profiles during skeletal muscle development, we performed a tandem mass tag (TMT)-based quantitative proteomic strategy in pectoralis major (breast muscle) of Beijing-You chicken (BYC) at the age of 90, 120 and 150 days. A total of 1,413 proteins in chicken breast muscle and 197 of them were differentially expressed (fold change ≥ 1.2 or ≤ 0.8333 and p < 0.05). There were 110 up- and 71 down-regulated proteins in 120 d vs. 90 d group, 13 up- and 10 down-regulated proteins in 150 d vs. 120 d group. The proteomic profiles of BYC at 120 d were very similar to those at 150 d and highly different from those at 90 d, suggesting that 120 d might be an important chronological age for BYC. Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that these differentially expressed proteins were mainly involved in the pathway of glycolysis/gluconeogenesis, adrenergic signaling in cardiomyocytes, focal adhesion, oocyte meiosis and phagosome. Protein expression analysis indicated that the differences in muscle growth rate between ages were regulated by proteins such as LDHA and ENO3, whereas ATP2A1 and HSP70 were associated with water-holding capacity (WHC), and PPP1CB and COL1A2 were suggested to lie in the role of intramuscular fat (IMF) deposition. In addition, RACK1 was thought to be crucial for the sexual maturation during chicken development. Furthermore, some DEPs were quantified using parallel reaction monitoring (PRM) to validate the results from TMT analysis. Overall, the present work could strengthen our view of the temporal expression profile during development and identify novel biomarkers for genetic breeding of chickens.
Project description:Relative expression levels of mRNAs in chicken cecal epithelia experimentally infected with Eimeria tenella were measured at 4.5 days post-infection. Two weeks old chickens were uninfected (negative control) or were orally inoculated with sporulated oocysts of Eimeria tenella. Cecal epithelia samples were collected from >12 birds in infected or uninfected group at 4.5 d following infections, in which samples from 4 birds were pooled together to form a total 3 biological replicates in each group. Parasite merozoites were also collected from four infected chickens at 5 d after infections. Uninfected control samples, merozoites and infection group samples were selected for RNA extraction and hybridization on Affymetrix microarrays. We used Affymetrix GeneChip chicken genome arrays to detail the chicken cecal epithelia gene expression in the control and E. tenella-infected birds.