As consumer demand for quality fish products continues to rise, quality has become a key factor in market competition. Ecological aquaculture research is exploring various farming methods to balance high-quality demand with environmental protection. This study compared three aquaculture models—cage culture (CG), recirculating aquaculture (RAG), and rice–fish co-culture (RG)—by analyzing muscle quality (AOAC, GC-MS), intestinal microbiota (16S rRNA), and liver metabolism (LC-MS) to assess their effects on M. albus. In terms of muscle quality, the RG group showed increased levels of EPA and DHA, reduced muscle moisture and crude lipid content, and enhanced crude protein accumulation. The crude protein content was significantly higher in the RAG group than in the CG group (p < 0.05). The RG group also had the highest levels of total, essential, and umami amino acids, followed by the RAG and CG groups. In terms of intestinal microbiota, the RG group had the highest microbial diversity and stability, with increased abundance of Firmicutes and Bacteroidetes and decreased levels of Proteobacteria. Compared to the CG, the RAG group also showed increased microbial diversity and a reduction in pathogenic genera. Liver metabolomics analysis demonstrated that the RG group had significant advantages over the CG group in amino acid, lipid, and energy metabolism. The RAG group exhibited upregulation of glycerophospholipid metabolism and a decrease in oxidative stress marker levels. Overall, the RG group enhanced muscle quality and optimized intestinal and liver metabolism in M. albus.

This study aimed to evaluate the impact of substituting a portion of feed with Tenebrio molitor (TM) and Elodea nuttallii (EN) on crayfish culture. A total of 270 crayfish (5.1 ± 0.4 g) were fed three different diet combinations (A: 100% feed; B: 80% feed + 10% TM + 10% EN; C: 75% feed + 15% TM + 10% EN) for 12 weeks. The findings demonstrated that group C had an important beneficial impact on the growth performance of crayfish. This was evidenced by a rise in digestive enzyme activity (trypsin, lipase, and cellulase) in the intestinal and hepatopancreas, as well as an upregulation in the expression of growth-related genes (ghsr, igfbp7, mhc, mlc1, mef2, and pax7) in the muscle. Furthermore, the assessment of the flesh quality of crayfish muscle in group C was conducted. The findings indicated a significant increase (p < 0.05) in the energy value (moisture, crude protein, and crude lipid) within the muscle. The levels of delicious amino acids (Glu, Ala, Ser, Gly, and Tyr) and polyunsaturated fatty acids (ARA, DHA) were enhanced, resulting in an improved nutritional profile and flavor of the muscle while maintaining the Σn-3/Σn-6 ratio. The remodeling of the intestinal microbiota (abundance of Proteobacteria and ratio of Firmicutes/Bacteroidota bacteria) also revealed improved growth performance. Additional research is necessary to ascertain whether excessive use of TM or EN feed substitution can have negative effects on crayfish culture.

Intensive aquaculture of rice field eel (Monopterus albus) is constrained by oxidative stress induced by high-density culture resulting in growth inhibition, while prophylactic antibiotics pose escalating risks of drug resistance and food safety hazards. This study addresses the critical need for developing efficient, environmentally friendly functional feed additives as sustainable growth promoters in intensive aquaculture. To investigate the dietary berberine (BBR) effect on promoting growth performance, hepatic antioxidant capacity and metabolism in M. albus, four experimental groups were established: control (CON, 0 mg/kg) and berberine-supplemented groups (BBR25, 25 mg/kg; BBR50, 50 mg/kg; BBR100, 100 mg/kg). Growth performance, serum biochemical parameters, hepatic antioxidant capacity, and liver metabolomics (LC-MS) were evaluated after the 8-week feeding trial. BBR50 and BBR100 had significantly increased final weight, weight gain rate (WG), and survival rate (SR), while reducing feed conversion ratio (FCR) (p < 0.05). Serum glucose (Glc), total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were decreased (p < 0.05), while high-density lipoprotein cholesterol (HDL-C) and phosphofructokinase (PFK) activity were increased (p < 0.05). Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were significantly reduced (p < 0.05). Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were upregulated (p < 0.05), whereas malondialdehyde (MDA) was downregulated (p < 0.05). Metabolomics identified 98 differential metabolites, with significant enrichment of metabolites associated with arachidonic acid metabolism, histidine metabolism, arginine/proline metabolism, tryptophan metabolism, and pathways related to mTOR signaling. Overall, dietary supplementation with 50 mg/kg BBR emerged as a practically favorable dose among the tested concentrations for promoting growth performance and feed utilization efficiency, whereas 100 mg/kg BBR was associated with lipid and amino acid metabolic alterations suggestive of metabolic reprogramming and antioxidant-related shifts, without conferring additional growth benefits.