AUTHOR=Vakili Farzaneh , Roosta Zahra , Safari Roghieh , Raeisi Mojtaba , Hossain Md. Sakhawat , Guerreiro Inês , Akbarzadeh Arash , Hoseinifar Seyed Hossein 

TITLE=Effects of dietary nutmeg (Myristica fragrans) seed meals on growth, non-specific immune indices, antioxidant status, gene expression analysis, and cold stress tolerance in zebrafish (Danio rerio)

JOURNAL=Frontiers in Nutrition

VOLUME=9

YEAR=2023

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.1038748

DOI=10.3389/fnut.2022.1038748

ISSN=2296-861X

ABSTRACT=<sec><title>Introduction</title><p>A medicinal plant, <italic>Myristica fragrans</italic> seed meal (nutmeg), was utilized to evaluate its impact on the growth, immunity, and antioxidant defense of zebrafish (<italic>Danio rerio</italic>).</p></sec><sec><title>Methods</title><p>In this regard, zebrafish (0.47 ± 0.04 g) (mean ± S.D.) were fed with 0% (control), 1% (T1-nutmeg), 2% (T2-nutmeg), and 3% (T3-nutmeg) of powdered nutmeg for 70 days. At the end of the feeding trial, growth performance, survival rate of fish, and temperature-challenge effects were recorded. Immune and antioxidant parameters were also assessed through the collection of serum and skin mucus samples.</p></sec><sec><title>Results</title><p>The results indicated that nutmeg supplementation did not significantly influence the growth of zebrafish (<italic>P</italic> &gt; 0.05); however, the survival rate of fish fed with 2 and 3% of nutmeg supplementation significantly decreased (<italic>P</italic> &lt; 0.05). The skin mucus and serum total protein, total immunoglobulin (Ig), and lysozyme activity were significantly increased in T3-nutmeg treatment in comparison to the control (<italic>P</italic> &lt; 0.05). Superoxide dismutase (SOD) and catalase (CAT) activities were also enhanced in the T3-nutmeg group (<italic>P</italic> &lt; 0.05). Nutmeg supplementation significantly upregulated the mRNA expression of <italic>growth hormone (gh)</italic> and <italic>insulin growth factor-1</italic> (<italic>igf-1</italic>). Moreover, the nutmeg inclusion upregulated the expression of <italic>interleukin-1</italic>β (<italic>IL-1</italic>β), <italic>lysozyme, sod</italic>, and <italic>cat</italic>. The dietary supplementation of nutmeg significantly increased the resistance of zebrafish against cold-water shock and survivability afterward (<italic>P</italic> &lt; 0.05).</p></sec><sec><title>Discussion</title><p>In conclusion, the supplementation of 3% powdered <italic>nutmeg</italic> in zebrafish diets could be suggested as an effective immune stimulator that improves antioxidant defense and stress tolerance.</p></sec>