Effect of dietary levels of folic acid on growth performance, blood biochemistry, antioxidant capacity, and immunity of juvenile largemouth bass, <i>Micropterus salmoides</i>

To obtain the optimal requirement of dietary folic acid (FA) in feed juvenile largemouth bass, Micropterus salmoides, five experimental diets were prepared with 0, 0.5, 1.5, 4.5, and 13.5 mg/kg supplemental FA basal practical diet (measured value <0.18 diet) fed to bass an initial body weight (14.49 ± 0.06) g for 7 weeks. The results showed that gain rate specific growth fish each supplementation group higher than those control varying degrees reached maximum values at 1.5 group, which significantly FA-free group; increase addition reduced visceral ratio (visceral somatic index), liver ratio, relative intestine weight. ≥0.5 increased whole protein content. hemoglobin content hematocrit blood cells supplemented 0.5–1.5 FA, 0.5 number red cells. Plasma total albumin levels then decreased reaching a mg/kg, differed from group. more plasma alanine transaminase (GPT) activity improved GPT activity, serum malonaldehyde hepatic antioxidant capacity, catalase head kidney lysozyme activity. above glycogen In conclusion, performance, hematopoiesis, metabolism carbohydrate, capacity liver, protected health bass. Regression analysis based on performance amount was 1.42–1.46 mg/kg.