乳制品-酵母益生元对星斑川鲽幼鱼生长性能和抗氧化能力的影响

选取平均初始体重为15.05±0.04g的星斑川鲽幼鱼540尾，随机分成6组，每组3个重复，分别饲喂添加0、0.4%、0.8%、1.2%、1.6%和2.0%乳制品-酵母益生元的试验饲料，实验期56d。结果表明：1）饲料中添加乳制品-酵母益生元可显著提高星斑川鲽幼鱼的增重率(WGR)、特定生长率(SGR)、摄食率(DFI)、蛋白质效率(PER)及肥满度(CF)(P<0.05)，显著降低饲料系数(FCR)(P<0.05)，但对星斑川鲽幼鱼的脏体比(VSI)、肝体比(HSI)无显著影响(P>0.05)。2）饲料中添加乳制品-酵母益生元显著提高了星斑川鲽幼鱼血清过氧化氢酶(CAT)、总超氧化物歧化酶(T-SOD)、抗超氧阴离子自由基(O2-?)的活性和总抗氧化能力(T-AOC)(P<0.05)，显著提高星斑川鲽幼鱼肝脏中总超氧化物歧化酶(T-SOD)活性和总抗氧化能力(T-AOC)(P<0.05)，同时显著降低了血清和肝脏中丙二醛(MDA)的含量(P<0.05)。本研究条件下，饲料中添加乳制品-酵母益生元可提高星斑川鲽幼鱼的生长性能及抗氧化能力，以特定生长率为评价指标，二次回归分析得出星斑川鲽幼鱼饲料中乳制品-酵母益生元的适宜添加量为1.32%。

Effect of dairy-yeast prebiotic on growth performance and antioxidant capability of juvenile starry flounder Platichthys stellatus

An 8-week feeding trial was conducted to study the effect of dairy-yeast prebiotic (Grobiotic-A) on the survival rate, growth performance and antioxidant capacity of juvenile starry flounder Platichtahys stellatus. A total of 540 fish at body weight of 15.05±0.04 g were randomly allocated into six groups with three replicates and each replicate contained 30 fish. The fish were fed diets supplemented with 0, 0.4%, 0.8%, 1.2%, 1.6% and 2.0% dairy-yeast prebiotic, respectively. The results are shown as follows: 1) weight gain rate (WGR), specific growth rate (SGR), feed intake (FI), protein efficiency rate (PER) and condition factor (CF) increased whereas feed conversion ratio (FCR) decreased significantly (P<0.05) with the supplementation of dairy-yeast prebiotic in diets. However, there were no statistical differences in viscerosomatic index (VSI), hepatosomatic index (HSI) (P>0.05); 2) compared with the control, the activity of catalase (CAT) and total anti-oxidation capability (T-AOC) in serum and liver, and superoxide dismutase (SOD) and anti-superoxide anion activities (T-AOC) in serum were significantly increased (P<0.05), while the malondialdehyde (MDA) content in serum and liver of fish fed diets supplemented with dairy-yeast prebiotic was significantly decreased (P<0.05). These results indicated that dairy-yeast prebiotic positively influenced the growth performance and anti-oxidation of juvenile starry flounder in this experiment. Quadratic regression of SGR indicated that the optimal supplementation level of dairy-yeast prebiotic in juvenile starry flounder diet was 1.32%.