In spite of various advantages of biofloc technology in aquaculture, few studies have focused on the health status of fish in biofloc system. In this survey, the effect of cane molasses as a carbon source of biofloc system on hemato-immunological parameters, antioxidant status, and stress indicators of common carp (Cyprinus carpio) was investigated. Four hundred and twenty juvenile common carp (40.2 ± 5.76 g) were randomly divided into four equal groups in triplicates as follows: groups A, B, and C were reared in biofloc system with molasses as a carbon source with C/N ratio of 15, 20, and 25, respectively, whereas control group (D) was reared in similar intensity without biofloc system. Fish were reared for 90 days and samples were taken on days 0, 30, 60, and 90 of the experiment. Immunological parameters including serum lysozyme and bactericidal activity, serum complement and IgM level, and NBT reduction and resistance to bacterial challenge as well as hematological parameters (RBC, WBC, hematocrit, hemoglobin) were assessed in experimental groups. Meanwhile, antioxidative enzyme activity (glutathione and superoxide dismutase, catalase) and stress indicators (glucose and cortisol level) were measured and compared among the groups. Water quality parameters were evaluated in all groups. Results showed that most of the immunological parameters as well as resistance against bacterial infection increased in biofloc groups (particularly in C/N = 20 groups) (P < 0.05). Hematological parameters and antioxidative enzyme activity were not affected by biofloc systems. Stress indicators showed a significant decrease in biofloc system, particularly in C/N = 20 group compared with control (P < 0.05). The results indicated that biofloc system (particularly C/N ratio = 20 groups) could not only improve immunological parameters, antioxidative status, and water quality but it decreased stress statues of common carp.

尽管生物絮凝技术在水产养殖中具有多种优势，但很少有研究关注生物絮凝系统中鱼类的健康状况。在该调查中，甘蔗糖蜜作为生物絮凝系统对造血-免疫学参数，抗氧化状态，和鲤鱼的压力指标的碳源的作用（鲤）进行了调查。将四百二十只幼年鲤鱼（40.2±5.76 g）随机分成四个等份，一式三份：将A，B和C组以糖蜜作为碳源在生物絮凝系统中饲养，C / N比为15。分别为20、25和25，而对照组（D）在没有生物絮凝剂系统的情况下以相似的强度饲养。将鱼饲养90天，并在实验的第0、30、60和90天取样。在实验组中评估了免疫学参数，包括血清溶菌酶和杀菌活性，血清补体和IgM水平，NBT降低和对细菌攻击的抵抗力以及血液学参数（RBC，WBC，血细胞比容，血红蛋白）。同时，抗氧化酶的活性（谷胱甘肽和超氧化物歧化酶，测量并比较各组之间的过氧化氢酶和应激指标（葡萄糖和皮质醇水平）。在所有组中评估水质参数。结果表明，生物絮凝剂组（尤其是C / N = 20组）的大多数免疫学参数以及对细菌感染的抵抗力均增加（P  <0.05）。血液参数和抗氧化酶活性不受生物絮凝系统的影响。压力指标显示生物絮凝系统明显减少，特别是在C / N = 20组中，与对照组相比（P  <0.05）。结果表明，生物絮凝系统（特别是C / N比= 20组）不仅可以改善免疫学参数，抗氧化性和水质，而且可以降低鲤鱼的胁迫状态。