Effect of Astragalus membranaceus on Transcriptome and Survival of Hybrid Yellow Catfish (Pseudobagrus vachellii ♂ × Tachysurus fulvidraco ♀) in Response to Aeromonas hydrophila Challenge

Abstract

Intensive culturing of hybrid yellow catfish (Pseudobagrus vachellii ♂ × Tachysurus fulvidraco ♀) has increased their mortality. Astragalus membranaceus has been used as an immune stimulant and antioxidant in fish for several years. A. membranaceus was decocted and mixed with the diet. After feeding for 28 d, the hybrid yellow catfish were challenged with Aeromonas hydrophila. To better understand the function of A. membranaceus in the defense of hybrid yellow catfish against A. hydrophila, we analyzed the spleen transcriptome data and relative percentage survival (RPS). There were 396 differentially expressed genes (DEGs) between the A. membranaceus and control groups at 24 h after A. hydrophila stimulation, including 263 upregulated and 133 downregulated DEGs. A significant enrichment of DEGs was found in the A. membranaceus group when the GO enrichment terms in the spleen were analyzed. The qRTPCRresults for the five upregulated and two downregulated DEGs from the spleen, intestine, and liver were consistent with the transcriptome data. The relative percentage survival of A. membranaceus was 85.71% after the fish were challenged with A. hydrophila.