Dietary supplementation of  Haematococcus pluvialis  improved the immune capacity and low salinity tolerance ability of post-larval white shrimp,  Litopenaeus vannamei

Zhang

et al. 2021

Aquaculture Research

This study was conducted to evaluate the effect of Haematococcus pluvialis powder on astaxanthin content and isomer composition, antioxidant ability and immunity of Litopenaeus vannamei after short‐term feedings. Experimental diets include a commercial diet (control) and diets containing H. pluvialis powder (HP‐35 and HP‐70, 35 and 70 mg of carotenoids kg−1). After feeding for 15 days, the content of astaxanthin in the muscle, cephalothorax and shell of shrimp increased significantly with increasing addition of H. pluvialis powder (p < 0.05). Dietary addition of H. pluvialis powder significantly increased the activity of total antioxygenic capacity (T‐AOC), superoxide dismutase (SOD) and glutathione S‐transferase (GST) as well as the relative mRNA levels of immune‐related genes, Toll, MyD88, IMD, Crustin, PO and Lysozyme in hepatopancreas (p < 0.05). The proportion of astaxanthin isomers in different body parts was different, whereas it has no significant difference between same body parts of different groups. This indicated that the accumulation of astaxanthin among body parts may be accompanied with selection and isomerization. In conclusion, feeding with H. pluvialis powder diets containing 35 and 70 mg of carotenoids kg−1 can enhance the carotenoid and astaxanthin content, antioxidant and immune capacity of L. vannamei.

Section: Discussionsupporting

confidence: 92%

Section: Introductionmentioning

confidence: 99%

Dietary Haematococcus pluvialis powder supplementation affect carotenoid content, astaxanthin isomer, antioxidant capacity and immune‐related gene expression in Pacific white shrimp, Litopenaeus vannamei

Zhang

et al. 2021

Aquaculture Research

“…After drying, the diets were broken up and ground using a mortar and pestle and graded via a series of different‐sized metal sieves. The size of the diets in our experiment was under 300 μm for L. vannamei at the adaptation feeding period (lasted for 3 days) and experiment period from day 1 to day 5, and then 300–450 μm from day 6 to day 10, 450–600 μm from day 11 to day 15, 600–900 μm from day 16 to day 20, and 900–1200 μm from day 21 to day 25, and this protocol was referred to Xie et al (). All the diets were stored at −20°C until used.…”

Section: Methodsmentioning

confidence: 99%

Optimal dietary lipid requirement of postlarval white shrimp, Litopenaeus vannamei in relation to growth performance, stress tolerance and immune response

et al. 2019

Self Cite

A 25‐day experiment was conducted to evaluate the optimal lipid level for postlarval Litopenaeus vannamei. Shrimp (1.7 mg) were fed five isonitrogenous diets containing grade levels of lipid (96.6, 114.3, 128.5, 136.5 and 154.5 g/kg diet, respectively). Each diet was assigned to four tanks (500 shrimp), and shrimp were fed six times a day. Weight gain was increased with the increasing dietary lipid levels, and the highest weight gain was observed in shrimp fed diet with 154.5 g/kg lipid (p < 0.05). On the contrary, the survival was lowest in shrimp fed the L15.45 and highest in shrimp fed the L11.43. Triglyceride in hepatopancreas was increased, and cholesterol was decreased with the increasing dietary lipid. Pyruvate kinase and AMPK mRNA expression were highest in shrimp fed the L12.85. Malondialdehyde in whole body was positively correlated with the dietary lipid levels. The mRNA expression of SOD and Caspase 3 was highest in shrimp fed the L12.85. After hypoxia stress, shrimp fed the L12.85 showed highest survival. The mRNA expression of superoxide dismutase and Akirin was highest in shrimp fed the L11.43 and L15.45, respectively. Based on the survival after 25‐day feeding trail and after the hypoxia stress, the optimal dietary lipid for postlarval L. vannamei should be 118–124 g/kg.

Front. Bioeng. Biotechnol.

“…Astaxanthin can enhance the salinity stress tolerance, and salinity stress test is a widely used criterion to predict the health status of shrimp. Xie et al (2018) found that dietary supplementation of 0.33-0.67% H. pluvialis improved the survival rate of white shrimp Litopenaeus vannamei under the salinity stress. One of the lipid peroxidation products malondialdehyde (MDA) and mRNA expression of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) decreased in white shrimp larval livers after salinity stress, whereas total antioxidant capacity (T-AOC) increased.…”

Section: Haematococcus Pluvialismentioning

confidence: 93%

Evaluation of Microalgae as Immunostimulants and Recombinant Vaccines for Diseases Prevention and Control in Aquaculture

Bao

et al. 2020

Microalgae are often used as nutritional supplements for aquatic animals and are widely used in the aquaculture industry, providing direct or indirect nutrients for many aquatic animals. Microalgae are abundant in nature, of high nutritional value, and some of them are non-toxic and rich in antioxidants so that they can be explored as a medicinal carrier for human or animals. Natural wild-type microalgae can be adopted as an immunostimulant to enhance non-specific immune response and improve growth performance, among which Haematococcus pluvialis, Arthrospira (Spirulina) platensis, and Chlorella spp. are commonly used. At present, there have been some successful cases of using microalgae to develop oral vaccines in the aquaculture industry. Researchers usually develop recombinant vaccines based on Chlamydomonas reinhardtii, Dunaliella salina , and cyanobacteria. Among them, in the genetic modification of eukaryotic microalgae, many examples are expressing antigen genes in chloroplasts. They are all used for the prevention and control of single infectious diseases and most of them are resistant to shrimp virus infection. However, there is still no effective strategy targeting polymicrobial infections and few commercial vaccines are available. Although several species of microalgae are widely developed in the aquaculture industry, many of them have not yet established an effective and mature genetic manipulation system. This article systematically analyzes and discusses the above problems to provide ideas for the future development of highly effective microalgae recombinant oral vaccines.