Effects of dietary Astragalus caudiculosus (Boiss & Huet, 1856) supplementation on growth, hematology, antioxidant enzyme activities, and immune responses in rainbow trout (Oncorhynchus mykiss Walbaum, 1792). Issue 122 (March 2022)

• Record Type: Journal Article
• Authors: Sönmez, Adem Yavuz; Bi̇len, Soner; Taştan, Yiğit; Nezih Kenanoğlu, Osman; Terzi, Ertugrul
• Is Part Of: Fish & shellfish immunology. Issue 122(2022)
• Page Start: 366
• Page End: 375
• Publication Date: 2022-03
• Subjects: Astragalus -- Feed additive -- Growth performance -- Immune response -- Cytokine gene expression -- Rainbow trout; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2022.02.031
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: The 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. Highlights: Astragalus caudiculosus (AC) was harnessed as a feed additive for rainbow trout. AC caused a significant improvement in growth parameters. It led to a partial improvement in the non-specific immunity and antioxidant enzymes. All cytokine gene expressions were up-regulated except IL-1β. 5% AC may be added into the feed to improve growth and immunity of the fish.