Abstract
Simple SummaryThis study investigated the effects of dietary andrographolide on the growth performance, antioxidant capacity, intestinal immune function and microbioma of rice field eel. This study indicated that the diets supplemented with low-dose andrographolide (75 and 150 mg/kg) significantly improved growth performance, enhanced antioxidant capacity and regulated the intestinal physical barrier and microbiota of M. albus. In addition, dietary supplementation of andrographolide upregulated of anti-inflammatory cytokines and downregulated of proinflammatory cytokines. The anti-inflammatory function of andrographolide may be related to the suppression of the toll-like receptor signaling pathway. These results can provide the valuable data for future rice field eel feeds.An eight-week feeding trial was conducted to investigate the effects of dietary andrographolide on the growth performance, antioxidant capacity in the liver, intestinal inflammatory response and microbiota of Monopterus albus. A total of 900 health fish (25.00 ± 0.15 g) were randomly divided into five groups: AD1 (the basal diet) as the control, and AD2, AD3, AD4 and AD5 groups, which were fed the basal diet supplemented with 75, 150, 225 and 300 mg/kg andrographolide, respectively. The results showed that compared with the control group, dietary andrographolide supplementation (1) significantly increased trypsin and lipase activities in the intestine, and increased the weight gain rate but not significantly; (2) significantly increased the levels of glutathione reductase (GR), glutathione (GSH) and glutathione peroxidase (GPx) and the content of in the liver; significantly decreased the contents of reactive oxygen species (ROS) and malondialdehyde (MDA); remarkably upregulated the Nrf2, SOD1, GSTK and GSTO mRNA levels in the liver; downregulated the Keap1 mRNA level; (3) significantly increased the villi length and goblet cell numbers in the intestine, remarkably upregulated the Occludin mRNA level in the intestine, downregulated the Claudin-15 mRNA level; (4) remarkably upregulated the IL-10, TGF-β1 and TGF-β3 mRNA levels in the intestine; downregulated the IL-12β and TLR-3 mRNA levels; (5) significantly decreased the richness and diversity of the intestinal microbioma, increased the percentages of Fusobacteria and Firmicutes and significantly decreased the percentages of Cyanobacteria and Proteobacteria. In conclusion, these results showed that dietary low-dose andrographolide (75 and 150 mg/kg) promoted growth and antioxidant capacity, regulated the intestinal microbioma, enhanced intestinal physical and immune barrier function in rice field eel.
Highlights
With the rapid expansion of the scale of aquaculture and the increasing degree of intensification as well as the inappropriate use of feed ingredients, the immunity and intestinal health of fish are being adversely affected [1]
feed conversion ratio (FCR), survival rate (SR), HIS, viserosomatic index (VSI) and condition factor (CF) showed no significant differences between the treatments (p > 0.05)
The final weight and weight gain rate (WGR) were higher in the AD2 group than those in the AD1 group but not significant (p > 0.05)
Summary
With the rapid expansion of the scale of aquaculture and the increasing degree of intensification as well as the inappropriate use of feed ingredients, the immunity and intestinal health of fish are being adversely affected [1]. The European Union began to restrict the use of feedstock antibiotics in 2006, and China has strengthened the management and application of antibiotics in recent years. There is an urgent need to search for alternative strategies to increase disease resistance for the development of antibiotic-free, sustainable aquaculture [3,4]. Effective components derived from plants and herbs have often been considered as an alternative eco-friendly feed additive strategy in aquaculture [5]. Andrographolide, a diterpenoid, is the main active ingredient of Andrographis paniculata, and its structural formula is C20 H30 O5 [12,13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
