Nano-selenium (nano-Se) removes the detrimental impacts of plant-based diets on the production performance and well-being of common carp (Cyprinus carpio)

Abstract

Fishmeal (FM) is not a sustainable source of nutrients due to the over-exploitation of fisheries resources and increasing aquafeed costs. Plant protein (PP) sources have been utilized as FM alternatives in diets. A 60-day nutritional experiment was conducted to study the effects of the complete replacement of FM with PP ingredients in diets supplemented with nano-Se on growth performance, plasma physiological and immunological parameters, and liver antioxidant capacity of common carp (Cyprinus carpio). Five experimental diets were prepared, where FM-Control contained 35 % FM, PP-Control contained complete PP ingredients, and NSe1, NSe2, and Nse3 contained complete PP ingredients supplemented with 1, 2, and 3 mg/kg nano-Se, respectively. The growth performance of fish fed the FM-Control and NSe3 diets was higher than in the PP-Control group (P 0.05). While the highest levels of antioxidant parameters, including reduced glutathione, superoxide dismutase, catalase, and glutathione peroxidase, were detected in the liver of fish fed with the FM-Control diet, the lowest malondialdehyde concentration was measured in the NSe3 group (P < 0.05). Plasma levels of lysozyme activity, alternative complement activity, and total immunoglobulin of the FM-Control and NSe3 groups were significantly higher than in other groups (P < 0.05). The best plasma physiological parameters including the lowest levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, cholesterol, triglycerides, and low-density lipoprotein, and the highest levels of total protein, triiodothyronine (T3), and high-density lipoprotein were observed in fish fed with the FM-Control and NSe3 diets (P < 0.05). These results suggest that FM can be entirely substituted by PP in diets containing nano-Se at 3 mg/kg without harmful impacts on the performance and immunity of common carp.

Keywords

• Cyprinus carpio
• Fishmeal
• Nano-selenium
• Performance
• Plant protein