Transcriptomic profiles of Pectoralis major muscles affected by spaghetti meat and woody breast in broiler chickens

Spaghetti meat (SM) and woody breast (WB) are breast muscle myopathies of broiler chickens, characterized by separation of myofibers and by fibrosis, respectively. This study sought to investigate the transcriptomic profiles of breast muscles affected by SM and WB. Targeted sampling was conducted on a flock to obtain 10 WB, 10 SM, and 10 Normal Pectoralis major muscle samples. Total RNA was extracted, cDNA was used for pair-end sequencing, and differentially expressed genes (DEGs) were determined by a false discovery rate of  1.5-fold change. Principal component and heatmap cluster analyses showed that SM and WB samples clustered together. No DEGs were observed between SM and WB fillets, while a total of 4,018 and 2,323 DEGs were found when comparing SM and WB, respectively, against Normal samples. In both SM and WB samples, Gene Ontology terms associated with extracellular environment and immune response were enriched. The KEGG analysis showed enrichment of cytokine–cytokine receptor interaction and extracellular matrix–receptor interaction pathways in both myopathies. Although SM and WB are macroscopically different, the similar transcriptomic profiles suggest that these conditions may share a common pathogenesis. The similarity between the two conditions may be used to find mitigation measures.