A four-week feeding trial on large yellow croaker, China’s top farmed marine fish, shows that Eucommia ulmoides in aquaculture feed at 0.3 percent lifted weight gain nearly twofold and halved the feed conversion ratio. Integrated transcriptomic and lipidomic data point to remodeled lipid pathways rather than a simple growth bump. Quick answer Eucommia ulmoides in aquaculture feed changed the growth and metabolism of large yellow croaker in four weeks. At 0.3 percent of diet, weight gain rose from 56.05 to 109.34 grams and the feed conversion ratio dropped from 2.68 to 1.38. Plasma triglycerides and a lipid-peroxidation marker fell while antioxidant markers rose. Multi-omics flagged glycerolipid and glycerophospholipid metabolism as…