Effects of dietary selenium on growth performance and oxidative stress in juvenile grass carpCtenopharyngodon idellus

Abstract

An 8‐week feeding trial was conducted to investigate the effect of dietary selenium (Se) on feed intake, weight gain and antioxidant activity in juvenile grass carp (11.2 ± 0.03 g). Six Se levels (0.13, 0.41, 0.56, 1.12, 2.18 and 4.31 mg/kg) of semi‐purified diets were assayed in triplicate. The maximum weight gain, specific growth rate and feed intake were obtained in fish fed with 1.12 mg Se/kg diet. Hepatic glutathione peroxidase activity was markedly increased when dietary Se ≤1.12 mg/kg diet and reached a plateau when dietary Se ≥1.12 mg/kg diet. Hepatic superoxide dismutase and serum catalase activities in juvenile grass carp fed with 0.56, 1.12 and 2.18 mg Se/kg diets were all significantly higher than those in the other groups. The malondialdehyde content in liver and serum was firstly decreased and then increased with increasing dietary Se content, and the lowest content was observed in fish fed with 1.12 mg Se/kg diet. With the increase in Se level, the activities of serum alanine aminotransferase and aspartate aminotransferase were reduced. In addition, serum alkaline phosphatase activity and albumin content were highest in fish fed with 1.12 mg Se/kg diet. This study indicated that both the Se deficiency and excess of Se caused negative effect on the oxidative stress in juvenile grass carp and suggested that the health‐giving concentration of dietary inorganic Se was 1.12 mg/kg diet. Moreover, based on the broken‐line regression analysis of weight gain, the optimal concentration of dietary inorganic Se was 0.83 mg/kg for juvenile grass carp.

Dietary nano‐selenium enhances antioxidant capacity and hypoxia tolerance of grass carp Ctenopharyngodon idella fed with high‐fat diet

“…The growth parameters (final average weight, WG and SGR) of the loach Paramisgurnus dabryanus (Sauvage) were not significantly affected by diet Se‐chitosan (Victor et al, ), and the growth performance of pacu ( Piaractus mesopotamicus ) was not significantly affected by different levels of Se‐yeast in diet (Takahashi et al, ). And the decreased growth rate in fish fed diet with 0.3 mg/kg Nano‐Se can be explained by the significantly reduced intraperitoneal fat and lipid content in hepatopancreas (not shown data), and this effect of Se on lipid accumulation has been reported by previous study (Liu et al, ). The survival rate of the fishes significantly increased compared to the control group when dietary Nano‐Se levels reached 0.6 mg/kg, and the improved antioxidant capacity of fishes (see details in section 3.3) might partially account for this positive effect.…”

“…Some studies have found that optimal Se in diets improved the growth performance of fish. About 0.83 mg/kg of dietary sodium selenite can significantly improve the growth of juvenile grass carp (Liu et al, ). Also, 1 mg/kg of dietary Nano‐Se can improve fish growth and antioxidant defence of common carp ( Cyprinus carpio ) (Ashouri et al, ).…”

“…Se as an essential nutrient for fish has been researched in many fish species, including grass carp (Liu et al, , ; Saffari, Keyvanshokooh, Zakeri, Johari, & Pasha‐Zanoosi, ; Xia et al, ; Zhou, Wang, Gu, & Li, ). Se nanoparticle (Nano‐Se) is the novel Se form and has attracted remarkable attention, as it exhibits higher bioavailability, lower toxicity and strong bioactivity in comparison with inorganic and organic Se (Saffari et al, , ; Zhou et al, ).…”

Optimum selenium requirement of juvenile Nile tilapia, Oreochromis niloticus

“…Nevertheless, a recent metabolomics study on Atlantic salmon implied that dietary Se may affect the abundance of pathway alteration in lipid metabolism (Berntssen et al, ). A previous study also showed that the whole body crude fat content was decreased and then increased with the increasing dietary Se in juvenile grass carp (Liu et al, ). The specific mechanism of Se on fish lipid metabolism deserves further investigations.…”

“…However, hepatopancreatic MDA content did not decrease at Se level of 0.57 mg/kg, while which owns the highest hepatopancreatic and serum GPx activity. In previous studies, MDA was negatively correlated with increasing GPx activity in common carp and gibel carp with Se supplement (Liu et al, ; Saffari, Keyvanshokooh, Zakeri, Johari, & Pasha‐Zanoosi, ). The increased hepatopancreatic SOD at dietary Se levels of 0.79 and 1.00 mg/kg may compensate for the lack of greater expression of GPx in this study, as SOD was reported to combat oxidative stress in conjunction with GPx in the antioxidant systems (Zee, Patterson, Wiseman, & Hecker, ).…”