Investigation into the effects of acute heat stress on stress level, meat quality, myofibrillar proteins properties and serum metabolites release of Muscovy ducks (Cairina moschata)

Abstract

This study systematically investigated the effects of acute heat stress (AHS) on Muscovy ducks, focusing on plasma stress indicators, meat quality, myofibrillar proteins (MPs) properties, and serum metabolite profiles. AHS significantly elevated stress level, impairing meat quality, as evidenced by higher L* value, shear force, drip loss, and cooking loss (P < 0.05). It also induced MPs oxidation and aggregation, reflected by elevated carbonyl content, turbidity, zeta potential, and particle size. MPs structural alterations were confirmed by fluorescence quenching and increased exposure of hydrophobic groups. Correlation analysis revealed strong associations between physicochemical changes and MPs oxidation. Metabolomic analysis identified 161 and 105 differential metabolites in the CON vs. LS and CON vs. SS comparisons, respectively, involving 25 metabolic pathways related to energy, amino acids, and fatty acids. These findings provide novel insights into the molecular pathways of AHS-induced meat quality deterioration and reveal potential intervention timing for the poultry industry.