UNASSIGNED: Specific pathogen-free shrimp with a body weight of 8.22 ± 0.03 g were randomly assigned to two groups with four replicates at a density of 15 shrimps per tank. Shrimp were cultivated in recirculating tanks containing 50 L of 15 ppt seawater in each replicate. Oxygen was supplied at 5 mg/L to the control tanks using an air microbubble generator and at 15 mg/L to the treatment tanks using a pure oxygen microbubble generator. Shrimp were fed commercial feed pellets containing 39% protein at 4% of their body weight per day for 30 days. Average daily growth (ADG) and feed conversion ratio (FCR) were determined on days 15 and 30. Shrimp molting was measured every day. Individual hemolymph samples were obtained and analyzed for total hemocyte count, differential hemocyte count, and expression of growth- and immune-related genes at the end of the experiment.
UNASSIGNED: Long-term exposure to supersaturated DO significantly affected shrimp growth. After 30 days of supersaturated DO treatment, the final weight and ADG were 14.73 ± 0.16 g and 0.22 ± 0.04, respectively. Shrimp treated with normal aeration showed significantly lower weight (12.13 ± 0.13 g) and ADG (0.13 ± 0.00) compared with the control group. FCR was 1.55 ± 0.04 in the treatment group and 2.51 ± 0.09 in the control group. Notably, the shrimp molting count was 1.55-fold higher in the supersaturated DO treatment than in the supersaturated DO treatment. The expression of growth-related genes, such as alpha-amylase, cathepsin L, and chitotriosidase, was 1.40-, 1.48-, and 1.35-fold higher, respectively, after supersaturated DO treatment. Moreover, the treatment increased the expression of anti-lipopolysaccharide factor, crustin, penaeidin3, and heat shock protein 70 genes by 1.23-, 2.07-, 4.20-, and 679.04-fold, respectively, compared to the controls.
UNASSIGNED: Supersaturated DO increased growth and ADG production and decreased FCR. Furthermore, enhanced immune-related gene expression by supersaturated DO may improve shrimp health and reduce disease risk during cultivation.
■将体重为8.22±0.03g的无特定病原体的虾随机分配到两组中,以每罐15只虾的密度进行四次重复。在每个重复中在含有50升15ppt海水的再循环罐中培养虾。使用空气微泡发生器向对照罐提供5mg/L的氧气,使用纯氧微泡发生器向处理罐提供15mg/L的氧气。每天以其体重的4%饲喂虾含有39%蛋白质的商业饲料颗粒30天。在第15天和第30天测定平均日生长(ADG)和饲料转化率(FCR)。每天测量虾蜕皮。获得单个血淋巴样本并分析总血细胞计数,血细胞分类计数,以及在实验结束时生长和免疫相关基因的表达。
■长期暴露于过饱和DO会显著影响虾的生长。经过30天的过饱和DO处理,最终体重和ADG分别为14.73±0.16g和0.22±0.04。与对照组相比,正常通气处理的虾体重(12.13±0.13g)和ADG(0.13±0.00)明显降低。治疗组FCR为1.55±0.04,对照组FCR为2.51±0.09。值得注意的是,过饱和DO处理的虾蜕皮计数比过饱和DO处理的虾蜕皮计数高1.55倍。生长相关基因的表达,比如α-淀粉酶,组织蛋白酶L,和壳三糖苷酶,是1.40-,1.48-,高出1.35倍,分别,过饱和DO处理后。此外,治疗增加了抗脂多糖因子的表达,Crustin,penaeidin3和热休克蛋白70基因由1.23-,2.07-,4.20-,679.04倍,分别,与对照组相比。
■过饱和DO增加了生长和ADG产量,并降低了FCR。此外,过饱和DO增强的免疫相关基因表达可能会改善虾的健康并降低养殖期间的疾病风险。