Dietary daidzein improves the development of intestine subjected to soybean meal in juvenile turbot (Scophthalmus maximus L.)

A 12-week feeding trial was conducted to investigate the effects of dietary daidzein on the intestinal development and growth performance of turbot subjected to soybean meal. Three isonitrogenous and isolipidic diets with 520 g/kg crude protein and 100 g/kg crude lipid were formulated: fish meal diet (FM), FM replaced by 400 g/kg soybean meal protein diet (SBM) and SBM supplemented with 40 mg/kg daidzein diet (DAID). Compared with SBM, DAID improved the growth performance of turbot. The normal and healthy distal intestinal appearance was observed in DAID group, which is similar to FM group, while the typical enteritis was observed in SBM group. Fish fed DAID had higher intestosomatic index, relative gut length and absorptive surface than fish fed SBM. Compared with SBM, DAID significantly increased the expression ofWingless-int(Wnt)10b,beta-catenin,c-mycandcyclin D1, and decreased theglycogen synthase kinase-3 beta(GSK-3 beta) expression. The transcriptome analysis between DAID and SBM showed that daidzein tended to promote cell proliferation, up-regulate the genes enriched in pathways such as cell cycle, oocyte meiosis and progesterone-mediated oocyte maturation. Therefore, the current study showed that dietary daidzein improved intestinal development of turbot, which might be related to the activation of Wnt/beta-catenin signalling pathway.

Automated summary

The study demonstrated that dietary daidzein improved growth performance and intestinal health of turbot, increasing intestosomatic index and absorptive surface, and activating the Wnt/beta-catenin signaling pathway.