To investigate the effect of dietary folic acid (FA) on growth performance, proximate composition, blood parameters, antioxidant status, and immune response of Siberian sturgeon, Acipenser baerii, six isonitrogenous and isolipidic experimental diets were formulated to contain graded levels of FA (0.60, 1.63, 2.71, 3.59, 4.82, and 5.68 mg kg⁻¹). Each diet was fed to triplicate groups of fish (4.36 ± 0.18 g) in a flow through water system for 8 weeks. Weight gain ratio (WGR) and specific growth rate (SGR) were thrived with increasing FA level up to 2.71 mg kg⁻¹ and decreased gradually thereafter (P < 0.05). The whole-body crude protein content was also highest in fish fed with 2.71 mg FA kg⁻¹ diet followed by those fed 3.59 and 1.63 mg FA kg⁻¹ diet. The muscle and liver FA concentrations were enhanced with increasing dietary FA supplementation with the values significantly higher in fish fed diets supplemented by equal to or more than 3.59 and 4.82 mg FA kg⁻¹, respectively. Red blood cells (RBCs), white blood cells (WBCs), hemoglobin (Hb), hematocrit (Hct), and lymphocyte count showed significant positive correlation with dietary FA level, whereas the neutrophil count was significantly declined by enhancing dietary FA supplementation (P < 0.05). Serum superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were also intensified by increasing dietary FA concentration. Fish fed diets supplemented with more than 1.63 and 2.71 mg FA kg⁻¹ had significantly higher lysozyme activity and immunoglobulin M (IgM) compared to those fed the basal diet. The dietary FA requirement of fingerling Siberian sturgeon was estimated by subjecting the SGR, crude protein content, liver FA content, and WBC count against varying levels of dietary FA which revealed the FA requirement in the range of 1.82–4.41 mg kg⁻¹.

为了研究生长性能，近似组成，血液参数，抗氧化状态，和西伯利亚鲟，的免疫应答膳食叶酸（FA）的效果西伯利亚鲟，六个氮和isolipidic实验饮食配制为包含FA的分级级别（0.60 ，1.63、2.71、3.59、4.82和5.68 mg kg ^-1）。每种饮食通过流水系统喂入三组鱼类（4.36±0.18 g），持续8周。随着FA含量增加至2.71 mg kg ^-1，体重增加率（WGR）和比生长率（SGR）迅速增加，此后逐渐降低（P  <0.05）。饲喂2.71 mg FA kg ^-1的鱼的全身粗蛋白含量也最高饮食，然后喂食3.59和1.63 mg FA kg ^-1饮食的人。肌肉和肝脏的FA浓度随着日粮中FA含量的增加而增加，在补充了等于或大于3.59和4.82 mg FA kg ^-1的鱼饲料中，其值明显更高。红血球（RBCs），白血球（WBCs），血红蛋白（Hb），血细胞比容（Hct）和淋巴细胞计数与饮食中FA水平呈显着正相关，而中性粒细胞计数则通过增加饮食中FA显着下降（P <0.05）。饮食中FA浓度的增加也增强了血清超氧化物歧化酶（SOD），过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GPx）的活性。与基础饮食相比，补充了1.63和2.71 mg FA kg ^-1以上的鱼类饮食具有较高的溶菌酶活性和免疫球蛋白M（IgM）。通过将SGR，粗蛋白含量，肝脏FA含量和WBC计数与不同水平的膳食FA进行比较，可以估算出幼鱼西伯利亚st的膳食FA需求量，这表明FA需求量在1.82–4.41 mg kg ^-1的范围内。