Abstract：
5-aminolevulinic acid (5-ALA) is an endogenous non-protein amino acid that is frequently used in modern agriculture. This study set out to determine how dietary 5-ALA affected the nonspecific immunity and growth performance of Litopenaeus vannamei. The shrimp were supplemented with dietary 5-ALA at 0, 15, 30, 45, and 60 mg/kg for three months. Transcriptome data of the control group and the group supplemented with 45 mg/kg dietary 5-ALA were obtained using transcriptome sequencing. 592 DEGs were identified, of which 426 were up-regulated and 166 were down-regulated. The pathways and genes associated with growth performance and nonspecific immunity were confirmed using qRT-PCR. The highest survival rate, body length growth rate, and weight gain values were observed in shrimp fed diets containing 45 mg/kg 5-ALA. L. vannamei in this group had a significantly higher total hemocyte count, phagocytosis rate and respiratory burst value than those in the control group. High doses of dietary 5-ALA (45 mg/kg, 60 mg/kg) significantly increased the activities of catalase, superoxide dismutase, oxidized glutathione, glutathione-peroxidase, phenoloxidase, lysozyme, acid phosphatase, and alkaline phosphatase. At the transcriptional level, dietary 5-ALA significantly up-regulated the expression levels of antioxidant immune-related genes. The optimal concentration of 5-ALA supplementation was 39.43 mg/kg, as indicated by a broken line regression. Our study suggested that dietary 5-ALA positively impacts the growth and nonspecific immunity of L. vannamei, providing a novel theoretical basis for further research into 5-ALA as a dietary supplement.
摘要：
5-氨基乙酰丙酸(5-ALA)是在现代农业中经常使用的内源性非蛋白质氨基酸。这项研究旨在确定饮食5-ALA如何影响凡纳滨对虾的非特异性免疫力和生长性能。虾补充了0mg/kg的饮食5-ALA，15mg/kg,30mg/kg,45mg/kg,和60mg/kg持续三个月。使用转录组测序获得对照组和补充45mg/kg膳食5-ALA的组的转录组数据。确定了592个DEG,其中上调426人，下调166人。使用qRT-PCR确认与生长性能和非特异性免疫相关的途径和基因。存活率最高,体长增长率，在含有45mg/kg5-ALA的虾饲粮中观察到增重值。南美白对虾的总血细胞计数明显较高，吞噬率和呼吸爆发值优于对照组。高剂量的饮食5-ALA（45mg/kg，60mg/kg)显著提高过氧化氢酶活性，超氧化物歧化酶,氧化型谷胱甘肽,谷胱甘肽过氧化物酶,酚氧化酶,溶菌酶,酸性磷酸酶,和碱性磷酸酶。在转录水平，膳食5-ALA显著上调抗氧化免疫相关基因的表达水平。补充5-ALA的最佳浓度为39.43mg/kg,如虚线回归所示。我们的研究表明，饮食5-ALA积极影响凡纳滨对虾的生长和非特异性免疫，为进一步研究5-ALA作为膳食补充剂提供了新的理论基础。
