This is an early access version, the complete PDF, HTML, and XML versions will be available soon.
Dynamic Structural Adaptation and Molecular Response of the Digestive Organs During Feed Domestication in Coilia nasus
1
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture/Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China
2
Hubei Hongshan Laboratory, Wuhan 430070, China
*
Authors to whom correspondence should be addressed.
Animals 2026, 16(10), 1518; https://doi.org/10.3390/ani16101518
Submission received: 31 March 2026
/
Revised: 5 May 2026
/
Accepted: 12 May 2026
/
Published: 15 May 2026
(This article belongs to the Section Animal Nutrition)
Simple Summary
The Coilia nasus is a valuable fish species native to the Yangtze River in China, but its wild populations have declined sharply due to overfishing and habitat loss. Artificial farming has become essential for protecting this species and meeting market demand. However, farmers currently rely on natural bait such as small shrimp and fish to feed these anchovies, which is expensive, unstable in supply, and can introduce diseases. This study explored whether C. nasus could be trained to eat formulated feed instead. We examined how its digestive organs, gut microbiota, and metabolic processes changed during the transition from natural bait to formulated feed. The results showed that the fish successfully adapted to formulated feed through structural changes in their stomach and intestines, adjustments in digestive enzymes, and shifts in gut microbiota communities. Importantly, C. nasus grew just as well on formulated feed as on natural bait, and their meat even showed improved nutritional quality. These findings provide a scientific basis for farmers to replace natural bait with formulated feed, making anchovy farming more sustainable, cost-effective, and environmentally friendly.
Abstract
Coilia nasus, a nutritionally and economically valuable migratory fish, has long relied on natural bait for its cultivation. However, the inherent instability of natural bait supplies poses a major bottleneck for large-scale aquaculture, necessitating a transition to formulated diets. To elucidate the adaptive response mechanisms underlying this dietary transition, we conducted sampling at three critical stages of feed domestication. This research revealed that while dietary shifts led to moderate alterations in muscle lipid and protein content, overall growth performance remained largely unaffected. During domestication, we observed significant structural remodeling of the stomach, intestine, and liver, along with increased activities of trypsin and lipase. The intestinal microbiota shifted, with Firmicutes abundance increasing notably during the domestication process, although the natural bait group exhibited even higher Firmicutes abundance than the formulated-feed group. Multi-omics analysis of intestinal samples from key domestication stages revealed significant enrichment of lipid metabolism pathways. It suggests that changes in genes and metabolites may be associated with the adaptive response to formulated-feed, including alterations in membrane stability, lipid metabolism and inflammatory state. This study provides the first comprehensive characterization of the structural and molecular adaptations of the digestive system of C. nasus during formulated-feed domestication. These findings offer a theoretical foundation for optimizing feeding protocols and supporting the sustainable aquaculture of this species.
