Requirement of vitamin E of growing sea cucumberApostichopus japonicusSelenka

Abstract

This feeding trial was conducted to determine the vitamin E requirement of growing sea cucumber Apostichopus japonicus Selenka. Six isonitrogenous and isoenergetic experimental diets were formulated to contain graded levels of vitamin E (6.7, 81.2, 159.3, 237.8, 314.6, 395.9 mg/kg diet). Each diet was assigned randomly to 30 growing sea cucumber with initial body weight 15.43 g in triplicates for 8 weeks. Survival rate was not affected by dietary vitamin E; meanwhile, both the weight gain (WG) and specific growth rate were presented the trend of increasing first and then kept stable. With the increasing of dietary vitamin E, crude lipid content of body wall was evaluated firstly and dropped afterwards. When dietary vitamin E contents were lower than 159.3 mg/kg, vitamin E contents of body wall were increased by dietary vitamin E levels, but there were no more differences when dietary vitamin E higher than 159.3 mg/kg. There were minor effects on digestive enzymes of intestine by dietary vitamin E. Contents of malondialdehyde were decreased, while the total superoxide dismutase activity was increased first and then decreased with the increasing of dietary vitamin E. Activities of intestinal alkaline phosphatase were increased, and glutamic oxaloacetic transaminase were decreased first and then increased with the increasing of dietary vitamin E. In conclusion, analysis by a linear regression equation of WG or vitamin E contents in body wall indicated that the optimum requirement of vitamin E for growing sea cucumber (initial body weight 15.43 g) was 165.2-187.2 mg/kg diet.

An Investigation on the Effects of Dietary Vitamin E on Juvenile Sea Urchin (Strongylocentrotus intermedius): Growth, Intestinal Microbiota, Immune Response, and Related Gene Expression

“…In this study, the WGR of sea urchins fed kelp was significantly higher than that in the dry feed groups. This was in accordance with the findings on this and other sea urchin species [9,14,44]. Kelp is rich in cellulose and mucus, which may be beneficial for protecting the fragile intestine and improving the digestibility of juvenile sea urchins [9,44].…”

“…The primer information can be found in Table 3. The relative expression was calculated by using the method of 2 −∆∆CT [9].…”

“…Since then, a series of studies was conducted on this species, including larval and juvenile production, farming technology, feed manufacture, and disease prevention and control [4][5][6][7][8]. Nowadays, S. intermedius has become one of the most important farming species, especially in the coastal areas of northern China [9,10]. Sea urchin seeds are the foundation of massive culture.…”

“…However, there are several defects of macroalgae, such as unstable supply, low feed conversion efficiency, and incomplete nutrition. Thus, it is essential to formulate feeds suitable for producing sea urchin seeds with higher efficiency [9,11,12].…”

Optimal dietary methionine requirement for juvenile sea cucumber Apostichopus japonicus selenka

“…It was higher than most fish species (Chu,et al., 2014; Elmada et al., 2016; Mai et al., 2006) and soft turtle (Huang & Lin, 2002), but close to the tiger shrimp (Millamena et al., 1996), calculated by % dietary protein. Numerous reports have illustrated that nutrients requirement were affected by animal species, size, age (Ko et al., 2009; Li et al., 2020; Wang et al., 2015) and nutrients form (Niu et al., 2018; Powell et al., 2017). But more importantly, the ingest rate of sea cucumber and tiger shrimp was much slower than that of fish, some of methionine was lost into water, so the data obtained from this trial may be higher than it is actually need.…”