Time-Dependent Stress Response to Force-Feeding Is Associated with Dynamic Gut Microbiota Changes in Mule Ducks

This study aimed to investigate the temporal dynamics of physiological and gut microbial responses in Mule ducks (M-D) during force-feeding (F-F), with the goal of identifying potential regulatory targets to reduce feeding stress. Male M-Ds were subjected to either F-F or ad libitum feeding. We conducted longitudinal analysis at 72, 78, and 84 days of age to assess growth performance, serum biochemical profiles, and intestinal inflammatory markers, while assessing gut microbiota composition through 16S rDNA sequencing. The F-F group exhibited superior growth performance. Initial physiological responses at day 72 included significantly reduced serum corticotropin-releasing hormone (CRH) and jejunal tumor necrosis factor-alpha (TNF−α). Conversely, F-F induced a persistent and profound alteration in the gut microbiome by day 84, characterized by reduced alpha diversity and a significant enrichment of the genus Limosilactobacillus. Correlation analysis identified Limosilactobacillus as a keystone taxon, strongly associated with intestinal metabolites. Our findings demonstrate that M-Ds undergo time-dependent metabolic and immunological adaptations in response to F-F stress, which correlates with distinct alterations in gut microbiota composition, particularly the enrichment of Limosilactobacillus. These findings provide a theoretical basis for developing microbiota-targeted strategies to alleviate F-F stress in foie gras production.