Dietary semen cuscuta improves laying performance by stabilizing mitochondria-associated membranes (MAMs) and inhibiting granulosa cell apoptosis in laying hens

The decline in laying performance during late-phase production of hens, primarily due to ovarian aging, poses significant economic challenges to the poultry industry. We have previously identified that Semen Cuscuta (SC), a traditional Chinese herbal medicine, could alleviate reproductive damage in mice, however, the therapeutic potential of SC in aging hens remains largely unexplored. In this study, different doses of SC (1%, 1.5%, or 2%) were dietary supplemented for 4 weeks, and serum, Ileum, ovarian tissues were collected for further detection/examination. Results showed that 1.5% and 2% SC significantly improved laying performance, enhanced systemic antioxidant capacity (increased serum SOD, decreased MDA), and elevated FSH levels. SC also reinforced intestinal barrier integrity, as indicated by improved villus morphology, upregulation of tight junction proteins (Occludin, ZO-1), and reduced serum endotoxin markers (D-LA, LPS). Moreover, SC modulated gut microbiota composition, increased cecal short-chain fatty acids (acetic and butyric acid), and upregulated intestinal specifically short-chain fatty acids (SCFA) receptors (GPR41, GPR43). In the ovary, SC suppressed granulosa cell apoptosis by modulating Bcl-2, Bax, Cleaved Caspase-3, and Cyt c expression. Notably, transmission electron microscopy revealed that SC preserved mitochondrial associated membrane (MAM) structural integrity and normalized the expression of MAM tethering proteins (IP3R, GRP75, VDAC1) in ovary. These findings demonstrate that SC ameliorates ovarian aging and restores laying performance through a dual mechanism: directly stabilizing ovarian MAMs to inhibit apoptosis, and indirectly remodeling gut microbiota to enhance intestinal barrier function and reduce systemic inflammation. This study provides a mechanistic basis for SC as a promising feed additive to improve sustainability in the production of aging hens.