Monier Mohamed N, Abd El-Naby Asmaa S, Fawzy Reham M, Samir Fatma, Shady Sherien H H, Grana Youssif Shehata, Albaqami Najah M, Abdel-Tawwab Mohsen
Department of Fish Biology and Ecology, Central Laboratory for Aquaculture Research, Agricultural Research Center, Abbassa, Abo-Hammad, 44662, Sharqia, Egypt.
Department of Fish Nutrition, Central Laboratory for Aquaculture Research, Agricultural Research Center, Abbassa, Abo-Hammad, 44662, Sharqia, Egypt.
Fish Physiol Biochem. 2025 Jan 9;51(1):6. doi: 10.1007/s10695-024-01426-2.
The current investigation assessed the beneficial impacts of dietary sodium chloride (NaCl) on the growth performance, oxidant/antioxidant, and immune responses of Nile tilapia (Oreochromis niloticus) and its adaptability to different salinity levels. After acclimating the fish to the laboratory conditions for 2 weeks, the acclimated fish (10.5 ± 0.16 g) were randomly distributed into 25 110-L rectangular glass tanks (15 fish/tank) to represent five groups in five replicates. The fish were fed with experimental feeds fortified with 0.0 (control), 5, 10, 15, and 20 g NaCl/kg feed for 60 days. Following the nutritional experiment, fish of all groups were adapted to different salinity levels from 0 to 32 g /L for a further 3 weeks, during which fish mortality was recorded. Blood samples were taken after the feeding trial and at a salinity level of 24 g/L. Growth performance and hematological parameters (WBCs, RBCs, hemoglobin, and hematocrit), total protein, albumin, globulin, digestive enzymes, antioxidant activity, and immunity status were markedly improved with increased NaCl rates in the fish diets up to 10 g/kg feed, after which all previous parameters were declined. On the other hand, feeding fish on a diet containing 10 g NaCl/kg feed showed substantially lower levels of cortisol, glucose, cholesterol, triglycerides, aspartate transaminase (AST), alanine transaminase (ALT), and malondialdehyde (MDA). Exposing the control fish group to salinity stress (32 g/L) for 3 weeks markedly decreased their digestive enzyme activity, immunity status, and antioxidant response, along with significant increases in cortisol, glucose, cholesterol, triglycerides, AST, ALT, and MDA levels. Conversely, feeding fish on a diet containing 10 g NaCl/kg feed alleviated the negative impacts of salinity stress and helped fish to tolerate salinity stress up to 24 g/L.
当前的研究评估了日粮氯化钠（NaCl）对尼罗罗非鱼（Oreochromis niloticus）生长性能、氧化/抗氧化和免疫反应的有益影响及其对不同盐度水平的适应性。在将鱼适应实验室条件2周后，将适应后的鱼（10.5±0.16克）随机分配到25个110升的长方形玻璃水箱中（每个水箱15条鱼），以代表五个组，每组重复五次。给鱼投喂添加了0.0（对照）、5、10、15和20克NaCl/千克饲料的实验饲料，持续60天。营养实验结束后，所有组的鱼再适应0至32克/升的不同盐度水平3周，在此期间记录鱼的死亡率。在投喂试验后以及盐度为24克/升时采集血样。随着鱼日粮中NaCl添加量增加至10克/千克饲料，生长性能和血液学参数（白细胞、红细胞、血红蛋白和血细胞比容）、总蛋白、白蛋白、球蛋白、消化酶、抗氧化活性和免疫状态均显著改善，之后所有先前参数均下降。另一方面，给鱼投喂含10克NaCl/千克饲料的日粮，其皮质醇、葡萄糖、胆固醇、甘油三酯、天冬氨酸转氨酶（AST）、丙氨酸转氨酶（ALT）和丙二醛（MDA）水平显著降低。将对照鱼组暴露于盐度应激（32克/升）3周，显著降低了它们的消化酶活性、免疫状态和抗氧化反应，同时皮质醇、葡萄糖、胆固醇、甘油三酯、AST、ALT和MDA水平显著升高。相反，给鱼投喂含10克NaCl/千克饲料的日粮减轻了盐度应激的负面影响，并帮助鱼耐受高达24克/升的盐度应激。
