Dietary phospholipid promotes growth, intestinal health, and muscle and ovarian development in largemouth bronze gudgeon (Coreius guichenoti)

The largemouth bronze gudgeon (Coreius guichenoti), an endemic and ecologically significant fish in the Yangtze River, has faced drastic population declines due to hydropower dam construction, necessitating artificial breeding for conservation. Despite the critical role of broodstock nutrition in reproductive success, species-specific dietary requirements remain unclear. This study evaluated the effects of dietary phospholipid (PLs) supplementation on ovarian development, intestinal health, and muscle growth in C. guichenoti through an 8-week feeding trial. Histological analyses demonstrated that PLs significantly increased oocyte diameter and gonadosomatic index (GSI), indicating enhanced ovarian maturation, without altering lipid deposition. Furthermore, PLs improved intestinal villus integrity and myofiber growth, suggesting superior nutrient absorption and muscle development. Transcriptomic profiling revealed three key pathways—amino acid/lipid metabolism, oxidative phosphorylation, and cell cycle regulation—as pivotal in PLs-improved ovarian development. Upregulation of cyclin-dependent kinases (CDKs) and oxidative phosphorylation genes implied elevated oocyte proliferation and energy provision, while arachidonic acid and glutathione metabolism pathways indicated roles in hormonal synthesis and antioxidant defense. Our results demonstrate that dietary PLs not only directly promote ovarian maturation but also enhance systemic physiological functions, thereby optimizing broodstock reproductive performance. These findings unraveled the effects of PL supplementation on C. guichenoti breeding efficiency, contributing to conservation and sustainable aquaculture practices in the Yangtze River ecosystem.