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High-starch diets disrupt glucose and lipid metabolism in fish, which in turn leads to impaired liver function and growth. Although quercetin has been shown to reduce blood glucose and cholesterol levels in mammals, its role in aquaculture fish remains poorly understood. To address this knowledge gap, five experimental diets were formulated: LS (8 % starch without quercetin), HS (16 % starch without quercetin), HSQ200 (16 % starch with 0.02 % quercetin), HSQ400 (16 % starch with 0.04 % quercetin), and HSQ800 (16 % starch with 0.08 % quercetin). Juvenile largemouth bass (initial weight: 10.02 ± 0.05 g) were fed respective diets for 10 weeks. Compared with the LS group, the HS group exhibited significant growth inhibition and liver damage. Notably, quercetin supplementation significantly improved weight gain (WG), specific growth rate (SGR), and protein efficiency ratios (PER); reduced blood glucose, serum triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and liver enzyme activities (AST and ALT). Mechanically, quercetin decreased liver glycogen levels by upregulating genes related to glucose metabolism (g6pc1a, pfkla, and slc2a1b). It also reduced liver TG, TC, and lipid content by downregulating lipid metabolism-related genes (fasn, acaca, cd36, and fabp4a). Furthermore, quercetin lowered reactive oxygen species (ROS) levels by upregulating antioxidant genes (cat, gpx7, sod1), enhancing antioxidant enzyme activity, and alleviating oxidative stress. These findings demonstrate that, quercetin protects against high-starch-induced liver injury through multiple pathways involving oxidative stress and metabolism. For optimal growth performance and hepatoprotection, dietary supplementation with 400 mg/kg quercetin is recommended in a high-starch diet for largemouth bass.

Hermetia illucens (HI) meal is a promising substitute for fish meal (FM) in the feeds of farmed fish. However, the impacts of dietary HI meal on largemouth bass (LMB) remain unknown. In this study, we formulated three isonitrogenous and isolipid diets with 0% (HI0, control), 20% (HI20) and 40% (HI40) of FM substituted by HI meal. A total of 270 juvenile largemouth bass with an initial body weight of 10.02 ± 0.03 g were used (30 fish per tank). After an 80-day feeding trial, the fish fed with the HI40 diet demonstrated decreased growth performance and protein efficiency ratio (PER), and increased liver oxidative indices and lipid accumulation compared to the control (P

Largemouth bass (LMB, Micropterus salmoides), a commercially important farmed fish, is vulnerable to heat stress. Breeding heat-resistant LMB is highly desirable in the face of global warming. However, we still lack an efficient method to assess the heat resistance of LMB. In this study, the critical thermal maximum (CTmax) and static exposure methods were first performed to assess the heat resistance of LMB juveniles. The CTmax values of the experimental fish (average body weight 9.87 ± 3.14 g) ranged from 39 to 40 °C but were too close together to differentiate the individual heat resistance. Static exposure experiments with varying temperatures and fish groups also did not provide a clear method for determining the heat resistance. To address these limitations, we developed a tiered exposure method, where the temperature was increased step-wise, starting from 28 to 34 °C at 2 °C increments and then at 0.5 °C increments above 34 °C, with each step lasting one day. The heat resistance of the fish was quantified as the lethal cumulative temperature (LCT), allowing for the classification of fish as sensitive or resistant to heat stress based on their LCT values. To correlate the changes in tissue structure and gene expression with the heat resistance, a new batch of LMB juveniles (average body weight 23.66 ± 6.98 g) were subjected to tiered heat exposure. Brain and liver tissues were collected from the control (without heat exposure), resistant and sensitive (still alive but demonstrated abnormal symptoms) individuals when the temperature was maintained at 35.5 °C for 24 h. The liver tissues of the heat-sensitive individuals showed significant damage and increased cell apoptosis (p < 0.05) relative to those of the resistant ones. The ddit3/chop, bax and casp3 genes demonstrated differential expressions in the liver of the sensitive and resistant fish. Additionally, the LMB juveniles (average body weight 84.06 ± 20.95 g) were found to be more heat resistant than the adults from different sources (average body weight 364.29 ± 84.43 g and 545.71 ± 184.56 g). Through the tiered exposure method, extremely heat-resistant individuals were successfully selected from the population (average body weight 22.69 ± 6.89 g). These findings provide valuable insights into the thermal biology of LMB and the potential for breeding heat-resistant LMB varieties.

The aim of this study was to explain the mechanism underlying the liver injury of juvenile largemouth bass Micropterus salmoides in response to high-starch diet intake. Three diets were formulated with different starch levels, being abbreviated as treatment LS (low starch, 8.13% starch), MS (medium starch, 14.1% starch), and HS (high starch, 20.1% starch), respectively. Fish were fed with their respective diets to apparent satiation for 56 days. The results showed that growth retardation of the HS fish was associated with the reduction in feed intake rather than feed utilization. Histological evaluation of the livers showed that vacuolization was the most prevalent characteristic in the MS fish, while ballooning degeneration, apoptosis, fibrosis, and inflammation were observed in the HS fish. Transcriptome profiling suggested that liver inflammation was mediated by Tlr signal transduction, which activated the Pi3k/Akt/Nfκb signaling axis to promote the release of proinflammatory factors including Il-8 and Ip-10. Hepatocyte apoptosis was mediated by the extrinsic pathway through death receptors including Fas and Tnfr, which coordinately activated the Fadd/caspase-8 death signaling axis. An autonomous inhibition program was identified to counteract the apoptosis signal, and the PI3K/Akt signaling pathway might play an important role in this process through regulating the expression of iap and diablo. Liver fibrosis was mediated through the Tgf-β and Hh signaling pathways. Upon secretion, Tgf-β1/3 bound to TgfβrI/II complex on the liver cell membrane, which induced the phosphorylation of downstream Smad2/3. When Hh interacted with the membrane receptor Ptc, Smo was activated to initiate signaling, driving the activation of Gli. The activation of both Smad2/3 and Gli promoted their nuclear translocation thereby regulating the transcription of target genes, which resulted in the activation and proliferation of HSCs. The activated HSCs constantly expressed colla1 and ctgf, which facilitated substantial accumulation of ECM. It should be noted that the molecular mechanism of liver injury in this study was speculated from the transcriptome data thus further experimental verification is warranted for this speculation.

This study aimed to explore the effects of three medicinal plant (Perilla frutescens, Illicium verum, and Artemisia annua) extracts on growth, immune function and microflora of largemouth bass (Micropterus salmoides). Four isonitrogenous and isolipidic diets were formulated: basic feed (control, CON), 0.075% extracts of Perilla frutescens (PFE), Illicium verum (IVE), or Artemisia annua (AAE) feed. Apparently healthy fish (initial body weight of 8.20 ± 0.03 g; total number of 300) were randomly assigned into four groups in triplicate 25 fish tanks, and fish were fed with each of the four experiment feeds for 80 days. Compared with the CON group, groups IVE and AAE fish significantly improved growth performance (final weight, weight gain rate, and specific growth rates; P < 0.05) and decreased hepatic lipid content and hepatopancreas somatic index. Groups IVE and AAE significantly enhanced the hepatic antioxidant capacity (Catalase, Glutathione peroxidase dismutase, and Superoxide dismutase), and up-regulated the mRNA levels of hepatic tight junction protein (Occluding-1 and Claudin-1; P < 0.05) and anti-inflammatory cytokines (interleukin-10 and transforming growth factor-β; P < 0.05). In addition, groups IVE and AAE decreased the transaminase activity and the contents of D-lactic acid in serum (P < 0.05). Groups PFE and AAE significantly improved albumin and globulin contents in serum immunity (P < 0.05). In addition, IVE and AAE groups significantly increased the α-diversity of intestinal flora, reduced the abundance of underlying harmful bacteria (Plesiomonas and Aeromonas), and increased the abundance of probiotics bacteria (Lactobacillus and Weissella; P < 0.05). These results demonstrate that supplementation of feed with IVE and AAE can improve the immune function and change the abundance of intestinal flora, ultimately increasing growth of largemouth bass. Overall, PFE group did not perform well compare with the IVE and AAE groups.

Mulberry leaf is abundant in bioactive ingredients, and their release could be affected by different treatment technologies. In this study, the mulberry leaf was treated with methods of superfine grinding (MG), wall-broken (MB), and water extraction-methanol precipitation (ME). Three processing mulberry leaves were equally added to the feed of largemouth bass (Micropterus salmoides), respectively, and the growth, liver health and intestinal microorganisms were analyzed. According to statistical analysis, the growth of the three experimental groups was remarkedly better than that of the control group fed with a basic diet. The MB group had a higher specific growth rate (SGR) and weight gain rate (WGR) than the MG and ME groups. Mulberry leaf supplementation could significantly reduced blood glucose and serum total cholesterol (TC), very low-density lipoprotein (VLDL) and triglyceride (TG) levels, improved hepatic glycogen, lipid and TG levels, and these parameter values of the MB group were superior to the other treatments. Additionally, MB treatment could up-regulate the expressions of gpx and cat in the liver compared with the control and boost the activities of antioxidant enzymes (GSH-Px and CAT). Meanwhile, MB supplementation suppressed the expressions of pro-inflammatory cytokines (TNFα and IL-8) and up-regulated anti-inflammatory cytokines (IL-10 and TGF-β) in liver compared to the control group. Accordingly, the hepatic histostructure showed an improvement in the treatment group, and mulberry leaf could also dramatically lower the apoptosis of hepatic cells, particularly in the MB group. Furthermore, MB treatment reduced gut dysbiosis by limiting the development of gram-negative and possibly dangerous bacteria. In sum, this study firstly disclosed that the biological effectiveness of mulberry leaf might be impacted by various processing techniques. Especially MB-treatment effectively ameliorates glucose, lipid metabolism and liver immunology in largemouth bass.

Cyber-physical system (CPS) is the core technology of Industry 4.0. The deterministic behaviors of the CPS require real-time deterministic guarantee. Therefore, this paper improves the ant colony optimization (ACO) into a scheduling algorithm for time-triggered flows in time-sensitive network (TSN), a standard developed by the IEEE 802.1 Working Group that fully satisfies the strict end-to-end delay requirements of industrial applications. Simulation results show that the improved ACO (IACO) can schedule the time-triggered flows in the TSN excellently, and outperform the traditional ACO in convergence speed, optimization ability and the proneness to local optimum trap. To sum up, this paper provides an effective real-time guarantee for the TSNs.

The study aimed to evaluate the effect of replacing fish meal (FM) by cottonseed protein concentrate (CPC) on growth, immune respone and health status of largemouth bass, Micropterus salmoides. Fish (initial body weight: 12.21 ± 0.15 g) were fed five isonitrogenous and isolipid diets (48% crude protein and 12% crude lipid) with CPC replacing 0 (control, CPC0), 15% (CPC15), 30% (CPC30), 45% (CPC45) or 60% (CPC60) of fishmeal for 8 weeks. The results showed that weight gain, specific growth rate and protein efficiency ratio were not appreciably reduced until more than 30% of the FM protein was replaced with CPC. Fish fed CPC60 diet had the lowest hepatic antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX) activities and genes (SOD, CAT, GSH-Px) expression, but the highest malondialdehyde (MDA) level. Moreover, CPC60 diet significantly down-regulated the expression of anti-inflammatory genes (IL-10, TGF-β) and protein metabolism genes (P13K, AKT, m-TOR, S6K1), whereas up-regulated the expression of pro-inflammatory genes (IL-8, IL-1β, TNFα). Accordingly, the liver histological investigation showed that the histopathological alterations were dramatically increased in the CPC60 group compared to control and CPC30 group. In addition, the CPC60 group decreased the villi height and goblet cell number, and increased villi width and muscular thickness in midgut and hindgut compared with the other groups, respectively. Meanwhile, plasma diamine oxidase (DAO) activity, D-lactate and endotoxin contents increased markedly as the proportion of CPC increased. Notably, the increased dietary CPC levels down-regulated the expression of ZO-1, Claudin-1 and Occludin in intestine. The lower SOD, CAT activities and mRNA levels in intestine were also observed in CPC60 group. Broken-line model analysis based on WG against dietary CPC replacement level indicated that the optimum replacement level was 18.44% when supplemented with crystalline methionine and lysine. However, including too high proportion of CPC could suppress immune and antioxidant capacity, impair both the liver and intestinal health, and finally reduced growth of Micropterus salmoides.

The effects of diets supplement Foeniculum vulgare extract (FE) and Artemisia annua extract (AE), single or combined, on the growth, liver antioxidant capacity and intestinal flora immunity of Micropterus salmoides were investigated. Largemouth bass juvenile (10.77 ± 0.02 g) were divided into 4 groups and each group was fed with diets supplemented with or without the medicinal herb extracts (additive quantity: 0.05%) for 8 weeks. The results showed that the largemouth bass fed with diets supplemented with AE or a combination of the FE and AE (FAE) significantly enhanced the specific growth rate (SGR) and feed intake (FI). Furthermore, the largemouth bass fed with two medicinal herbs alone or in combination significantly increased the antioxidant enzyme activities (SOD and CAT) and their gene expression levels, and decreased the malondialdehyde (MDA) content in the liver (P

This study investigated the effects of yellow mealworm meal (TM) on growth performance, hepatic health and digestibility in juvenile largemouth bass (Micropterus salmoides). The fish were fed with the basic feed and the test feed (70% basic feed and 30% raw materials) containing Cr2O3, and feces were collected for digestibility determination. The fish were fed with five isonitrogenous (47% crude protein) and isolipidic (13% crude lipid) diets, in which fishmeal (FM) was replaced with 0% (TM0), 12% (TM12), 24% (TM24), 36% (TM36) and 48% (TM48) TM. The fish were reared in cylindrical plastic tanks in a recirculating aquaculture system for 11 weeks. The apparent digestibility coefficients (ADC), of dry matter, crude protein and crude lipid, in largemouth bass of TM were 74.66%, 91.03% and 90.91%, respectively. The ADC of total amino acid (TAA) of TM in largemouth bass was 92.89%, and the ADC of essential amino acid (EAA) in TM in largemouth bass was 93.86%. The final body weight (FBW), weight gain rate (WGR) and specific growth rate (SGR) in the TM24 group were significantly higher than those in other groups. Similarly, the highest mRNA expression levels of hepatic protein metabolism genes (pi3k, mtor, 4ebp2 and got) and antioxidant enzyme (glutathione peroxidase, Gpx; catalase, Cat) activities were observed in the TM24 group. Moreover, the expression levels of anti-inflammatory factors (il-10 and tgf) in liver were up-regulated and the expression levels of pro-inflammatory factors (il-8 and il-1β) in liver were down-regulated. Quadratic regression model analysis, based on weight gain rate (WGR) against dietary TM level, indicated that the optimum level of dietary TM replacing FM in largemouth bass diet was 19.52%. Appropriate replacement levels (less than 36%) of FM by TM in the diets can enhance the antioxidant capacity and immunity of largemouth bass. However, high levels of FM substitution with TM (more than 48%) in the feeds can damage the liver health and inhibit the growth of largemouth bass. Notably, largemouth bass has high ADC and high utilization of TM, which indicates that it is feasible to use TM as feed protein source for largemouth bass.

With the rapid development of electrification, both productivity and human civilization have made rapid progress and electrification has led to more and more fires. Therefore, it is of great significance to strengthen the investigation and prevention of fires, especially the confirmation of the origin of fire. Considering the post-combustion residual characteristics of common flammable production raw materials (carbon dioxide and dust) at the scene of the fire, this paper designs a detection system based on odor sensor for rapid detection, data analysis and recognition. The system designs a multi-function sensor array for detecting dangerous production raw materials (carbon dioxide and dust), and develop a good method for spot sampling. It introduces embedded technology and uses it together with chromatographic technology and sensor array, achieving the accurate detection of the combustion residues of dangerous production raw materials (carbon dioxide and dust) is realized. The detection signals are post-processed by feature extraction technology and pattern recognition algorithm. The research results are helpful for rapid analysis and recognition of residues, providing certain technical support for the recognition for the cause of fire.

Four isonitrogenous (gross protein content 30%) and isoenergetic (gross energy content 15 kJ/g) diets were formulated to investigate the effects of inclusion of plant proteins on the hybrid tilapia ( Oreochromis niloticus× Oreochromis aureus). The plant proteins tested were soybean meal (SBM), rapeseed meal (RSM), cottonseed meal (CSM), and peanut meal (PNM). In each diet, 30% of the protein was supplied by fish meal, and the rest of protein was supplied by the plant protein tested. Each diet was randomly fed to three groups of hybrid tilapia for 8 wk in a recirculating freshwater system. The results showed that the best performance in terms of final weight, specific growth rate, feed efficiency ratio, and protein efficiency ratio were shown in diets SBM and CSM. Four parameters were significantly affected by dietary RSM ( P < 0.05). The lowest feed intake was recorded in the group fed RSM, followed by groups CSM and SBM, and was highest in the group fed PNM. Whole-body moisture content in group PNM was significantly lower than that of other three groups ( P < 0.05). The liver lipid content in group RSM was significantly higher than that of other three groups ( P < 0.05). And viscera ratio, hepatosomatic index, condition factor, and the liver glycogen contents were not significantly different among ditary treatments ( P < 0.05). Protease activities of intestine in diets SBM and CSM are significantly higher than that of other two groups ( P < 0.05), and the lowest protease activities of intestine and hepatopancreas were found in group RSM. No significant differences were observed in amylase activities of intestine and hepatopancreas among four diet groups ( P > 0.05). The highest activities of glutamate-pyruvate transaminase, glutamate-oxaloacetate transaminase, and superoxide dismutase in the liver were observed in group SBM and the poorest in group RSM. The results show that 39% CSM may be included in the practical diets without inhibiting fish performance. Although the inclusion of 50% RSM resulted in significantly lower growth performance, it produced histopathological damage in the liver. [ABSTRACT FROM AUTHOR]

A 12-week feeding trial was conducted to investigate the effects of supplemental exogenous enzyme on growth performance in juvenile hybrid tilapia Oreochromis niloticus× O. aureus (18 g, average initial weight). A commercial enzyme complex (neutral protease, β-glucanase and xylanase) was included at the level of 0.0 (control group), 1.0 and 1.5 g kg−1 diet in three test diets. Each diet was fed to triplicate tanks of the juvenile three times a day at 4–6% of wet body weight, and each tank was stocked with 50 fish. The results showed that specific growth rate and feed efficiency ratio significantly increased ( P<0.05) with increasing dietary enzyme levels. The highest feed intake was recorded in the group fed the control diet ( P<0.05). The highest apparent protein retention was observed in fish fed the diet containing the 1.5 g kg−1diet ( P<0.05). No significant differences were observed in the apparent digestibilities (ADC) of protein, lipid and gross energy among dietary treatments ( P>0.05). However, the ADC of dry matter in fish fed high supplementation (1.5 g kg−1) was significantly higher than the control and low supplementation ( P<0.05). There were no significant differences in condition factor, whole body moisture, protein, lipid and ash among dietary treatments. Viscera ratio, hepatosomatic index and the liver lipid decreased significantly with increasing enzyme ( P<0.05). Both protease and amylase activities in the intestine and the hepatopancreas of juvenile hybrid tilapia significantly increased ( P<0.05) with increasing dietary enzyme levels. The results suggested that enzyme supplementation can significantly improve growth performance and feed utilization in juvenile hybrid tilapia. [ABSTRACT FROM AUTHOR]