Sönmez, Adem YavuzBi Len, SonerTaştan, YiğitNezih Kenanoğlu, OsmanTerzi, Ertugrul2023-04-062023-04-062022-03-011095-9947https://hdl.handle.net/20.500.12597/3335The potential dietary utilization of Astragalus caudiculosus (AC) in rainbow trout (Oncorhynchus mykiss) was investigated. Four different fish groups (control, AC1, AC2.5, and AC5) were assigned and received the AC-containing diet for 90 days at the rates of 0, 1, 2.5, and 5%, respectively. Results indicated that the growth performance of the AC supplemented fish improved significantly (P < 0.05). Among non-specific immune parameters examined, while lysozyme activity of the AC supplemented fish increased (P < 0.05), oxidative radical production decreased in AC1 and AC2.5 fish groups (P < 0.05) but did not differ in the AC5 group (P > 0.05) compared to the control. Moreover, myeloperoxidase activity was not affected by the AC supplementation (P > 0.05). All pro-inflammatory and anti-inflammatory cytokine gene expressions, except IL-1β, were up-regulated, especially in the fish groups fed with 2.5 and 5% AC supplemented feed (P < 0.05). AC administration caused an elevation in GPx and G6PDH activities, and a decrease in SOD, CAT, and lipid peroxidation (P < 0.05). Overall, AC extract was found to improve the growth, antioxidant status, and immune response of the fish.enAstragalusCytokine gene expressionFeed additiveGrowth performanceImmune responseRainbow troutJournal Article10.1016/j.fsi.2022.02.03135183741