Dietary Essential Fatty Acid Requirements of Juvenile Sterlet Sturgeon (Acipenser ruthenus)

An 8-week feeding trial evaluated the dietary essential fatty acid (EFA) requirements of juvenile sterlet sturgeon (Acipenser ruthenus, 37.1 g). Nine diets (45% protein, 10% lipid) were formulated with varying levels of linoleic acid (LA) and α-linolenic acid (LNA). The 0.5% LNA diet (LNA0.50) resulted in the highest weight gain, feed efficiency, and whole-body crude protein content (P<0.05). Increasing LNA to 1.0% did not improve growth but significantly elevated body lipid deposition (P<0.05). Whole-body fatty acid profiles directly reflected dietary compositions, showing dose-dependent accumulations. In conclusion, the optimal dietary LNA requirement for juvenile sterlet sturgeon is approximately 0.5% to maximize growth and nutrient retention, providing baseline data for customized sturgeon feed formulation.