High temperatures are important environmental stressors affecting the metabolism, growth, immunity, and mortality of Chinese mitten crabs (Eriocheir sinensis). In this study, Chinese mitten crabs were divided into two groups and exposed to temperatures of 35 °C (thermal stress group) or 25 °C (control group) for 24 h, and the transcriptome of the heart was analyzed. There were 4007 differentially expressed genes (DEGs) between the thermal stress and the control groups, including 2660 upregulated and 1347 downregulated genes. Heat shock proteins (HSPs) and transcription factors (TFs) were temperature-sensitive DEGs in Chinese mitten crabs. DEGs mainly focused on protein processing in the endoplasmic reticulum, ribosome biogenesis, glycine, serine, and threonine metabolism, protein export, and insect hormone biosynthesis pathways. A total of 28,916 SSRs and 59 TF families, including 851 TFs, were detected among all unigenes of E. sinensis transcripts. The qRT-PCR results for the HSPs and apoptotic DEGs from the heart exhibited the same trends as those in the E. sinensis transcriptome data. Results of light microscopy analyzing histological sections of the heart indicated that most myocardial fibers were lysed, and the number of nuclei and the connective tissue contents between the myocardial layers were both reduced following 35 °C exposure for 24 h.

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.

Feeding inefficiencies in pond aquaculture not only elevate operational costs and environmental impact but also compromise fish growth and welfare, driving an urgent need for precision feeding technologies. However, accurate, real-time detection of feeding events in complex, cluttered pond environments remains challenging due to dense, small targets, variable lighting, and background disturbances. To address these issues, we propose PM-YOLO, an enhanced YOLOv8n framework that integrates Parallelized Patch-Aware Attention modules for multi-scale feature retention and a Minimum Point Distance IoU loss term for superior bounding-box regression of overlapping fish. We also curate FeedFishDatas, a 7,400-image dataset capturing diverse feeding scenarios, and demonstrate that PM-YOLO achieves 87.7% precision and 83.5% mAP-50—outperforming standard YOLOv8n and YOLOv11n—while maintaining real-time inference at 8.1 ms per frame. Our ablation studies isolate the contributions of each innovation, confirming their synergistic impact on detection performance. Looking ahead, we envisage lightweight PM-YOLO variants via model pruning and quantization for edge deployment, temporal smoothing for stability, and domain adaptation to extend applicability across species and water conditions, paving the way for fully automated, closed-loop feeding systems in sustainable aquaculture.

This study investigated the influence of two distinct aquaculture systems, namely, the wheat-crab model (WCM) and pond culture (PC) model, on the growth, physiological well-being, and gut microbial structure of Chinese mitten crabs (Eriocheir sinensis). A total of 120 adult crabs were randomly selected from the two systems: 60 crabs from the WCM, including 30 females and 30 males, and 60 crabs from the PC model, also including 30 females and 30 males. The gonadosomatic index of female crabs in the WCM was notably higher than that of the other groups, while the hepatopancreatic index was significantly lower. Significant variations were not observed in final weight, fullness, or muscle yield between the WCM and PC groups. Biochemical evaluations indicated no substantial differences in antioxidant capabilities between the two systems; however, female crabs demonstrated increased critical antioxidant enzyme activity, such as for catalase and superoxide dismutase, and significantly elevated cholesterol levels. Additionally, the expression of the genes IL, ProPO, and Keap1 was significantly higher in the WCM group than the PC group, whereas the expression of ALF2, Myd88, and CncC did not significantly differ between the two cultivation methods. Non-targeted metabolomics analysis revealed notable distinctions in metabolite profiles between the two systems. Moreover, the WCM facilitated an increase in beneficial Firmicutes bacteria while reducing potentially harmful microorganisms, suggesting improved immune function in crabs raised under the WCM. In summary, female crabs reared in the WCM matured earlier and exhibited slightly better health conditions compared to those grown in the PC model.