Exploring the effects of feeding methods on the growth and meat flavor of Wenchang chicken

Wenchang chicken, renowned for its high-quality meat, is the economic meat breed in Hainan Province, China. This study compared cage-rearing (CR) and free-range (FR) groups in terms of growth performance, slaughter performance, meat quality, IMP (inosine monophosphate) content, AAs, FAs, serum lipid metabolites, and transcriptomic and metabolomic analyses. The CR group showed increased body weight, live weight, and abdominal fat but lower leg muscle percentage and breast muscle redness, suggesting flavor differences. CR chickens had higher IMP, threonine (Thr), and pentadecanoic, oleic, and linoleic acids, while glutamate (Glu) and alpha-linolenic acid were lower compared to FR. Glycine was elevated, but histidine, myristic, and tricosanoic acids were lower in CR leg muscle. Serum analysis revealed higher total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), lipoprotein lipase (LPL), hormone-sensitive lipase (HSL), fatty acid synthase (FAS), thyroid-stimulating hormone (TSH), leptin (LEP), and adiponectin (ADP) in the CR group. Transcriptomic and metabolomic studies identified 252 differentially expressed genes and 34 metabolites linked to metabolic pathways. In summary, CR system can improve production performance, FR system is considered more flavorful. The results can act as a theoretical basis for selecting a suitable rearing method for this unique breed.