SEARCH · PubMed Health

Results for “Recirculating aquaculture system”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

3 recordsLinked to original sources

PubMed2026

Multi-omics integrative analysis provides insight into potential molecular responses to sustained high water flow in common carp (Cyprinus carpio) cultured in recirculating aquaculture.

To investigate the potential molecular responses by which water flow intensity affects the growth of common carp (Cyprinus carpio) in a recirculating aquaculture system (RAS), a control group (CG, actual water velocity 0.3 cm/s) and three sustained flow treatment groups were established, including a low-flow group (LF, 1 body length per second, bl/s), a medium-flow group (MF, 2 bl/s), and a high-flow group (HF, 3 bl/s). After 12 weeks of culture in the RAS, growth performance was compared among groups under different flow intensities. The best-performing group and the control group were then selected for the determination of intestinal digestive enzyme activities, as well as transcriptomic and whole-genome bisulfite sequencing analyses of muscle tissue. The results showed that the specific growth rate and feed intake of the HF group were significantly higher than those of the other groups (P < 0.05), whereas no significant difference in feed conversion ratio was observed among groups. Compared with the CG group, lipase activity was significantly higher in the HF group (P < 0.05), while α-amylase and trypsin activities showed increasing trends without significant differences. RNA-seq identified a total of 273 differentially expressed genes, including 72 upregulated genes and 201 downregulated genes in the HF group relative to the CG group. These genes were mainly enriched in glycolysis, pyruvate metabolism, ATP metabolism, the pentose phosphate pathway, the insulin signaling pathway, the PPAR signaling pathway, and the adipocytokine signaling pathway, indicating that sustained high water flow induced a muscle transcriptional response characterized by remodeling of energy metabolism and substrate utilization. Whole-genome bisulfite sequencing analysis showed that DNA methylation in common carp muscle occurred predominantly in the CpG context. Differentially methylated regions between the HF and CG groups were mainly distributed in transcription-related regulatory regions, including promoters, CpG islands, and CpG island shores. In promoter regions, the number of hypermethylated regions in the HF group relative to the CG group was markedly higher than that of hypomethylated regions. Integrated analysis further identified two candidate genes showing both promoter differential methylation and differential expression, namely LOC109094644 and bcorl1, suggesting that adaptation to high water flow may involve IGF-related growth regulation and remodeling of upstream transcriptional programs. The qPCR results were consistent with the transcriptomic data. Taken together, within the tested range, a sustained water flow of 3 bl/s was more conducive to the growth of common carp in the RAS, which may be associated with enhanced lipid digestion and utilization, remodeling of the muscle energy metabolic network, changes in promoter methylation, and the coordinated regulation of key candidate genes. This study provides a theoretical basis for clarifying the exercise adaptation mechanism of common carp in recirculating aquaculture and for optimizing flow velocity parameters.

Animals↗

PubMed2026

Antibacterial and preventive effects of Terminalia chebula Retz. aqueous extract and methyl gallate in American shad Alosa sapidissima (Wilson, 1981) against Aeromonas hydrophila YML1.

American shad, Alosa sapidissima (Wilson, 1981), is an economically important emerging species in recirculating aquaculture systems and photovoltaic aquaculture. However, Aeromonas hydrophila poses a threat to the healthy development of its aquaculture industry. This study investigated the effects of 95.5 mg·L-1 aqueous extract from Terminalia chebula Retz. and 318.3 mg·L-1 methyl gallate (Experiment I) and methyl gallate at 31.8-127.3 mg·L-1 (Experiment II) together with A. hydrophila YML1 challage groups (1.0 × 107 and 1.58 × 105 CFU·mL-1 in Experiments I and II) on liver morphology, hepatic enzyme profiles, and transcriptional responses in American shad. Results for Experiment I showed after high-dose pathogen infection, vacuolar degeneration and inflammatory cell infiltration were observed. In addition, caspase-3, tumor necrosis factor α (TNF-α), and malondialdehyde (MDA) contents increased significantly, and the steroid biosynthesis pathway was significantly enriched via the transcriptional analysis. However, inflammation and apoptosis remained evident after high-dose A. hydrophila YML1 infection. After treatment with 95.5 mg·L-1 T. chebula Retz. extract, triphosphopyridine nucleotide (NADPH), Fructose-1,6-bisphosphatase (FBP), and phospho fructo kinase 1 (PFK) levels decreased significantly. After treatment with 318.3 mg·L-1 methyl gallate, nicotinamide adenine dinucleotide (NADH), NADPH, PFK, caspase-3, TNF-α, and MDA contents decreased significantly. For Experiment II, caspase-3 and TNF-α also decreased in the 31.8 mg·L-1 group at 24-96 h and in the 127.3 mg·L-1 group at 96 h. The peroxisome proliferator-activated receptor (PPAR) signaling pathway and fatty acid metabolism were also significantly enriched after methyl gallate treatment.Different expression genes (DEGs) in the cytokine-cytokine receptor interaction pathway showed a time- and dose-dependent pattern. At 48 h, the MAPK signaling pathway and apoptosis were enriched in the 95.5 mg·L-1 group, whereas at 96 h the PPAR-MAPK (mitogen-activated protein kinase) signaling pathway was enriched, with downregulation of fabp7b, soat2, cpt1ab2, and pparg. These changes were associated with inflammatory cell infiltration and increased MDA contents. Enhanced fatty acid degradation, possibly via cpt2, together with reduced fatty acid transporter transcription, may have alleviated liver injury in shad.

American shad↗

PubMed1979

Thermal pollution consequences of the implementation of the president's energy message on increased coal utilization.

The thermal consequences of coal utilization are most meaningfully assessed in comparison with the form of power generation replaced by coal which is most likely nuclear. The different effects are influenced by siting decisions and the intrinsic thermal efficiencies of the two fuel systems. Nuclear power plants discharge 50% more waste Rheat to the atmosphere through cooling towers or to a water body than coal-fired plants. Coal-fired plants require about 2/3 as much water as nuclear power plants. Nearly every property of water is affected nonlinearly by temperature, and biological effects may amplify these changes because protein denaturation takes place more rapidly above 30 degrees C and these high temperatures affect bactericidal and viricidal activity of chlorine compounds. Usually algal populations change from a dominance of diatoms and green algae to dominance by blue-green algae. All organisms experience elevated metabolic rates at higher temperatures which may affect total energy needs, foraging ability, reproduction, migration and susceptibility to disease. Intake structures inevitably draw many organisms into the cooling system of a power plant, but the number and kind are influenced by its location, configuration, and mode of operation. Use of water recirculation systems reduces water use and with it, the number of organisms entrained. Mechanical damage in the cooling system to small organisms is generally low, but fish and their larvae and eggs may be seriously damaged. Discharge effects may also be severe but are generally local. The near field, where there are strong shear velocities and rapid temperature changes are particularly stressful to fish, and stringent limitations on the timing and strength of discharges may be required to reduce these stresses to nondamaging levels. Off-stream cooling systems may increase cloudiness, ground fog, precipitation, temperature and local winds, but these effects generally extend no further than 1000 m even in winter. There is considerable potential for using condenser cooling water for agricultural and aquacultural purposes such as irrigation, frost protection, undersoil heating, greenhouse heating and climate control. However, over the next few decades little of this waste heat is likely to be used creatively. The thermal consequences of implementing NEP are locally serious but do not pose regional problems. Creative use of the waste heat for aquaculture, agriculture, cogeneration, and power for energy intensive industries can be a powerful means of mitigating undesirable effects.

Animals↗