مشخصات پژوهش

This work examines the impacts of nutritional selenium nanoparticles (SeNPs) on growth, physiological and immunological parameters, antioxidant defense capacity, gene expression, and stress response of fingerling Arabian yellowfin seabream (Acanthopagrus arabicus). SeNPs were added to the basal diet at different dosages of 0 (control), 0.5 (SeNPs-0.5), 1 (SeNPs-1), and 2 (SeNPs-2) mg/Kg diet. The fish with an average weight of 5 ±0.0 g were indiscriminately distributed in 12 tanks (20 fish/ tank) to represent four experimental groups in triplicate that received the diets for 60 days. The results revealed that the SeNPs-1 and SeNPs-2 diets improved growth, feed intake, and feed conversion ratio. Supplemental SeNPs enhanced the expression levels of insulin- like growth factor I, interleukin-1β, and lysozyme genes. Although supplementing SeNPs had no significant ef- fect on superoxide dismutase activity and malondialdehyde concentration, it enhanced the catalase activity in the SeNPs-1 group and the glutathione peroxidase activity in groups supplemented with SeNPs at 0.5 and 1 mg/ Kg. The immune parameters improved in fish fed with the SeNPs-1 diet. While SeNPs had no significant impact on plasma total protein, albumin, globulin, alanine aminotransferase, and triglyceride contents in different groups, the SeNPs-1 group had the highest content of plasma high-density lipoprotein and simultaneously the lowest values of cholesterol and low-density lipoprotein. The SeNPs-0.5 and SeNPs-1 diets reduced plasma aspartate aminotransferase content, and the SeNPs-2 diet increased its value. Additionally, SeNPs significantly decreased blood cortisol and lactate levels in fish challenged with acute stress by being confined at the fish density of 200 kg/m3 for 45 min. According to these data, SeNPs at 1 mg/Kg diet is recommended to enhance growth, immunity, and stress resistance in the fish under study.