AUTHOR=Zhang Ming , Liang Huifen , Lei Yifan , Zhang Yiwen , Tan Zhigang , Chen Wenzhen , Li Shengkang , Peng Xianfeng , Tran Ngoc Tuan 

TITLE=Aspergillus niger confers health benefits and modulates the gut microbiota of juvenile Pacific white shrimp (Penaeus vannamei) under farming conditions

JOURNAL=Frontiers in Marine Science

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1211993

DOI=10.3389/fmars.2023.1211993

ISSN=2296-7745

ABSTRACT=<sec><title>Introduction</title><p>The fungus <italic>Aspergillus niger</italic> is found to be predominant in the body of Pacific white shrimp (<italic>Penaeus vannamei</italic>); however, its role in shrimp’s health has not been explored. This study aimed to evaluate the influences of A. niger on growth, antioxidative activity, immune response, and gut microbiota of juvenile Pacific white shrimps under farming conditions.</p></sec><sec><title>Methods</title><p>Shrimps (2.30±1.05 g) were fed diets supplemented with 0 (control), 1.5 (A1.5), or 3.0 g/kg diet of <italic>A. niger</italic> (A3.0) for one month. At the end of the study, the growth, antioxidant enzyme activity and immune parameters, and gut microbiota in shrimps fed with different experimental diets were analyzed.</p></sec><sec><title>Results</title><p>The results showed a significant increase in weight gain, specific growth rate, and length gain of shrimps in A1.5, compared with other groups (<italic>P</italic>&lt;0.05). With the exception of lysozyme in both A1.5 and A3.0, which were lower than in the control, the activity of superoxide dismutase (SOD), catalase, acid phosphatase, alkaline phosphatase, and phenol oxidase was higher than those in the control. Gene expressions of SOD, anti-lipopolysaccharide factor-ALF1, and ALF2 (in A1.5 and A3.0) and nitric oxide synthase, penaeidin-PEN2 (in A1.5) and PEN3 and PEN4 (in A3.0) were significantly up-regulated compared to the control (<italic>P</italic>&lt;0.05). The addition of <italic>A. niger</italic> increased diversity and separated the microbial community in the gut of shrimps. At the phylum level, Firmicutes and Bacteroidota were dominant, and Proteobacteria was less abundant in the A1.5 and A3.0, as compared to the control. At the genus level, the relative abundance of <italic>Vibrio, Marivita</italic>, and <italic>Roseobacter</italic> was increased but <italic>Ruegeria</italic> was decreased in A1.5 and A3.0 when compared to the control. The genera <italic>Edwardsiella, Clostridium sensu stricto 1</italic>, and <italic>Shimia</italic> in the A1.5 were higher than in the control.</p></sec><sec><title>Discussion</title><p>These findings demonstrated the beneficial effects of <italic>A. niger</italic> on growth, health, and changes in the gut microbiota in shrimps under farming conditions. The recommended concentration of <italic>A. niger</italic> in the diet for shrimps is 1.5 g/kg diet.</p></sec>