Growth Performance, Immune-Related and Antioxidant Genes Expression, and Gut Bacterial Abundance of Pacific White Leg Shrimp, Litopenaeus vannamei, Dietary Supplemented With Natural Astaxanthin

Abstract

The current study examines the effect of dietary supplementation of ethanolic extract of Arthrospira platensis NIOF17/003, which is mainly natural astaxanthins (97.50%), on the growth performance, feed utilization, bacterial abundance, and immune-related and antioxidant gene expressions of the Pacific white leg shrimp, Litopenaeus vannamei. A total of 360 healthy L. vannamei postlarvae (0.19 ± 0.003 g) were divided into four groups (0, 2, 4, and 6 g natural astaxanthins/kg diet) each in three replicates, at an initial density of 30 PLs per tank (40 L capacity). The shrimp were fed the tested diets three times a day at a rate of 10% of their total body weight for 90 days. Diets supplemented with different astaxanthin levels significantly improved shrimp growth performance and feed conversion ratio compared to the control diet. No significant differences were observed in survival rates among all experimental groups. The immune-related genes (prophenoloxidase, lysozyme, beta-glucan binding protein, transglutaminase, and crustin) mRNA levels were significantly upregulated in groups fed with different concentrations of the natural astaxanthins in a dose-dependent manner. The prophenoloxidase gene is the highest immune-upregulated gene (14.71-fold change) in response to astaxanthin supplementation. The superoxide dismutase mRNA level was significantly increased with increasing dietary astaxanthin supplementation. In addition, increasing astaxanthin supplementation levels significantly reduced the count of heterotrophic bacteria and Vibrio spp. in the culture water and shrimp intestine. Overall, the current results concluded that diet supplementation with natural astaxanthin, extracted from Arthrospira platensis, enhanced the growth performance, immune response, and antioxidant status of L. vannamei.

Impact of Dietary Administration of Seaweed Polysaccharide on Growth, Microbial Abundance, and Growth and Immune-Related Genes Expression of The Pacific Whiteleg Shrimp (Litopenaeus vannamei)

“…The current work reported that, compared to SWP 0 , the THB and TVC counts were significantly ( p > 0.05) decreased with the increase in the inclusion levels of polysaccharides (SWP 1 , SWP 2 , and SWP 3 ). These results are in agreement with those reported in the study by Mansour et al [ 87 ] who found that the increasing levels of astaxanthin, extracted from the cyanobacterium strain, Arthrospira platensis NIOF17/003, in L. vannamei diet significantly ( p > 0.05) decreased the counts of THB and TVC. However, the action mechanism of how seaweed-polysaccharide affected the abundance of microbiota is still not clear and requires further studies [ 87 , 101 ].…”

“…Gut microbiota abundance rapidly responds to variations in dietary intake, composition, and components. Therefore, it has a huge impact on the health benefits of all aquatic organisms such as food consumption, digestion, nutrient utilization, absorption, and immunity responses [ 22 , 87 , 100 , 101 ]. At present, the evaluation of disease resistance is important in the aquaculture industry, the blood antioxidant and immune factor activity is a good health status indicator for investigating the immune response and disease resistance in L. vannamei such as white spot syndrome virus (WSSV) [ 49 ] and Vibrio alginolyticus [ 102 ].…”

“…In SWP 3 treatment, the up-regulatory gene expression was noticeably higher. Results showed increased expression with the treatments compared to the control (SWP 0 ), suggesting that the polysaccharide can improve the immune status of shrimp through microbial cell walls composed of peptidoglycans, lipopolysaccharides (LPS), and β-1, 3-glucans, which can activate the shrimp immune response by triggering the main non-specific defense mechanism [ 22 , 87 , 105 , 106 ].…”

“…Both experimental diets and shrimp were subjected to proximate analysis for estimating their biochemical content according to AOAC [ 86 ] guidelines prepared as detailed in the prior article [ 87 ]. To estimate the whole-body constituent (dry matter, crude fat, crude protein, and crude ash), 5 shrimp were obtained randomly from each replicate after the feeding session was completed.…”

Commercial Seaweed Liquid Extract as Strawberry Biostimulants and Bioethanol Production

“…Seaweeds are marine organisms rich in numerous phytochemical bioactive compounds that can be used for commercial applications [ 9 , 10 , 11 , 12 , 13 , 14 ]. Seaweeds have applications in fuels [ 15 , 16 , 17 ], feed [ 18 , 19 , 20 ], bioremediation [ 21 , 22 , 23 , 24 ], and food products [ 25 , 26 ]. The Egyptian coasts of the Mediterranean [ 27 , 28 , 29 ] and Red Sea [ 30 , 31 ] offer a diverse range of wild seaweed genera that may renew and be harvested all year.…”