Effects of dietary lipid sources on the survival, growth, body composition, antioxidant capacity and expression of antioxidant and pro‐inflammatory genes in juvenile Chinese mitten crab ( Eriocheir sinensis ) reared under three salinities

Abstract

A 60‐day feeding experiment was performed to investigate the survival, growth, body composition, antioxidant capacity and related gene expression of Eriocheir sinensis which were fed diets with different lipid sources under three salinities. Five feeds were formulated with one of the candidate oils (fish oil, soybean oil, linseed oil, colza oil or palm oil) and were named FO, SO, LO, CO or PO respectively. Results showed that the survival rate (SR) of E. sinensis showed a decreasing tendency as the salinity increased. But SR was not significantly affected by dietary lipid sources at each salinity. Weight gain rate (WGR) were highest in the treatment of FO/PO at a salinity of 0.5‰, CO/FO/SO at a salinity of 2‰ and LO at a salinity of 6‰ respectively. At salinities of 0.5‰ and 2‰, the transcription of pro‐inflammatory and antioxidant genes in LO was significantly higher than that in FO or PO. While at a salinity of 6‰, the transcription of detected genes in FO was markedly increased compared to that in the vegetable oil treatments. At each salinity, the eicosapentaenoic acid (EPA) contents showed comparable values among different dietary treatments. However, the docosahexaenoic acid (DHA) contents in E. sinensis fed the diets with FO were still significantly higher than those with vegetable oils. These results showed that increasing salinity decreased the antioxidant capacity and therefore negatively affected the survival and growth rates of experimental animals. The beneficial effects of FO on survival and growth performance were eliminated by increasing the salinity to 6‰, which could be due to the increased lipid peroxidation and inflammatory response caused by salinity stress. It was concluded that at the salinity of 0.5‰ and 2‰, the recommended lipid sources were FO/PO and CO/FO/SO respectively. While at the salinity of 6‰, LO was the most ideal lipid source for juvenile E. sinensis.

Growth, biochemical indices and transcriptomic profile of Chinese mitten crab (Eriocheir sinensis) respond to different ratios of dietary carbohydrates to lipids

“…(Ma et al, 2019) and C. quadricarinatus (Zhu et al, 2013). In this study, the lipid level in the C/L9.42 was only 3.92%, which was lower than the estimated requirement for E. sinensis (Li et al, 2013;Zhang et al, 2016;Wen et al, 2021). In this study, hepatic glycogen contents in the hepatopancreas significantly increased, while triglyceride (TG) contents decreased with increasing dietary C/L.…”

“…The present study showed that, post the 58-day feeding trial, the SR of E. sinensis was above 90% and was hardly affected by dietary C/L. Carbohydrates and lipids can be effectively used to achieve ideal growth performance by most crustaceans, such as Jasus edwardsii, Cherax quadricarinatus (Zhu et al, 2013), E. sinensis (Bao et al, 2020;Wen et al, 2021). In the present study, the optimal dietary C/L for juvenile E. sinensis was estimated to be 3.59 based on WGR.…”

“…Therefore, the steady state of carbohydrates and lipids metabolism is particularly important. It was previously found that the supplementation of carbohydrates or lipids can improve the growth performance and disease resistance of E. sinensis (Chen et al, 2016;Wen et al, 2021). Molting is an important biological process closely related to the growth of crustaceans.…”

An investigation on the optimal lipid level for juvenile Chinese mitten crab ( Eriocheir sinensis ) reared under three salinities: Survival, growth, digestive enzyme activities, antioxidant capacity and body composition

“…This indicated that lipid peroxidation reaction inside the E. sinensis could be accelerated by high lipid level and salinity. Recently, a study of our research team found that fish oil was more prone to be oxidized than the other lipid sources under salinity stress (Wen et al, 2021). This could be due to the abundant n‐3 LC‐PUFA in the fish oil, which was easily oxidized (Du et al, 2010; Huang et al, 1998).…”

“…It is well known that the larvae of E. sinensis complete metamorphosis in estuarine and coastal waters, while the larval Macrophthalmus must adapt to declining salinity during their migrating to inland waters (Cheng et al, 2008). Due to salinity stress, high mortality and low growth rate of E. sinensis often occur in some of the Liaohe River Basin areas (Wen et al, 2021). Salinity stress has a significant impact on the growth and development, physiological status and nutritional composition of crustaceans (Chen et al, 2014;Long et al, 2017Long et al, , 2018.…”