Proteomic responses to the effect of coprophagy prevention on meat quality in New Zealand white rabbits

Coprophagy is an innate behavior of rabbits, and rabbit meat is favored by consumers for its distinctive nutritional characteristics. However, the relationship between coprophagy and meat quality in rabbits remains unclear. Therefore, this study investigated the effects of coprophagy prevention on growth performance and meat quality using a coprophagy-prevention model. The results showed that coprophagy prevention reduced growth performance and several meat quality parameters while increasing muscle fiber density. In addition, coprophagy prevention altered the nutritional composition of skeletal muscle by reducing unsaturated fatty acids (UFAs) and essential amino acids (EAAs), while increasing total lipid content and the proportion of saturated fatty acids (SFAs). Tandem mass tag (TMT)-based quantitative proteomic analysis identified 267 differentially expressed proteins (DEPs) in skeletal muscle following coprophagy prevention, which were mainly enriched in pathways related to muscle development, energy metabolism, fatty acid transport, and lipid metabolism. Further analyses suggested that alterations in lipid deposition and fatty acid composition may be associated with changes in mitochondrial oxidative phosphorylation and ATP production; however, these mechanistic relationships require further validation. Although several cognition-related pathways and reduced serum dopamine (DA) and 5-hydroxytryptamine (5-HT) levels were observed, the functional significance of these findings remains unclear due to the lack of behavioural assessments. Overall, the present study suggests that coprophagy prevention is associated with impaired growth performance and altered meat quality in rabbits. These findings provide preliminary insights into the potential metabolic changes associated with coprophagy prevention and highlight the biological importance of coprophagy in rabbit production.