Chronic heat stress inhibits glycogen synthesis through gga-miR-212-5p/GYS1 axis in the breast muscle of broilers.

Studies have demonstrated that chronic heat stress can accelerate glycolysis, decrease glycogen content in muscle, and affect muscle quality. However, the consequences of chronic heat stress on glycogen synthesis, miRNA expression in pectoralis major (PM) muscle, and its regulatory functions remain unknown. In this study, high-throughput sequencing and cell experiments were used to explore the effects of chronic heat stress on miRNA expression profiles and the regulatory mechanisms of miRNAs in glycogen synthesis under chronic heat stress. In total, 144 cocks were allocated into 3 groups: the normal control (NC) group, the heat stress (HS) group, and the pair-fed (PF) group. In total, 30 differently expressed (DE) miRNAs were screened after excluding the effect of feed intake, which were mainly related to metabolism, signal transduction, cell growth and death. Furthermore, the gga-miR-212-5p/GYS1 axis was predicted to participate in glycogen synthesis through the miRNA-mRNA analysis, and a dual-luciferase reporter test assay confirmed the target relationship. Mechanistically, chronic heat stress up-regulated gga-miR-212-5p, which could inhibit the expression of GYS1 in the PM muscle. Knocking down gga-miR-212-5p alleviates the reduction of glycogen content caused by chronic heat stress; overexpression of gga-miR-212-5p can reduce glycogen content. This study provided another important mechanism for the decreased glycogen contents within the PM muscle of broilers under heat stress, which might contribute to impaired meat quality.

Effects of guanidinoacetic acid supplementation on growth performance, hypothalamus-pituitary-adrenal axis, and immunity of broilers challenged with chronic heat stress.

Heat stress can cause systemic immune dysregulation and threaten the health of broilers. Guanidinoacetic acid (GAA) has been shown to be effective against heat stress, but whether it is beneficial for immunity is unclear. Therefore, the effects of dietary GAA supplementation on the immunity of chronic heat-stressed broilers were evaluated. A total of 192 Arbor Acres male broilers (28-day old) were randomly allocated to 4 treatments: the normal control group (NC, 22°C, ad libitum feeding), the heat stress group (HS, 32°C, ad libitum feeding), the pair-fed group (PF, kept at 22°C and received food equivalent to that consumed by the HS group on the previous day), and the GAA group (HG, 32°C, ad libitum feeding; basal diet supplemented with 0.6 g/kg GAA). Samples were collected on d 7 and 14 after treatment. Results showed that broilers exposed to heat stress exhibited a decrease (P < 0.05) in ADG, ADFI, thymus and bursa of Fabricius indexes, and an increase (P < 0.05) in feed conversion ratio and panting frequency, compared to the NC group. Levels of corticotropin-releasing factor, corticosterone (CORT), heat shock protein 70 (HSP70), IL-6, and TNF-α were elevated (P < 0.05) while lysozyme and IgG concentration was decreased (P < 0.05) in the HS group compared with the NC group after 7 d of heat exposure. The concentrations of IgG and IL-2 were decreased (P < 0.05) and CORT was increased (P < 0.05) in the HS group compared with the NC group after 14 d of heat exposure. Noticeably, GAA supplementation decreased the levels of CORT (P < 0.05) and increased the IL-2, IgG, and IgM concentrations (P < 0.05) compared with the HS group. In conclusion, chronic heat stress increased CORT release, damaged immune organs, and impaired the immunity of broilers. Dietary supplementation of 0.6 g/kg GAA can reduce the CORT level and improve the immune function of broilers under heat stress conditions.

Effect of chronic heat stress on the carbonylation of glycolytic enzymes in breast muscle and its correlation with the growth performance of broilers.

Chronic heat stress has detrimental effects on the growth performance of broilers, and the potential mechanism is under exploration. In this study, the protein carbonyl modification was introduced to glycolytic enzymes to evaluate its relationship with the growth performance of heat-stressed (HS) broilers. A total of 144 male 28-day-old broilers were assigned to 3 treatments: the normal control group (NC, raised at 22°C with free access to feed and water), the HS group (raised at 32°C with free access to feed and water), and the pair-fed group (PF, raised at 22°C with an amount of feed equal to that consumed by the HS group on a previous day). Results showed that heat stress decreased the average daily growth, increased the feed-to-gain ratio (F/G), decreased breast muscle rate, and increased abdominal fat rate compared with the NC and PF groups (P < 0.05). Higher cloacal temperature and serum creatine kinase activity were found in the HS group than those of the NC and PF groups (P < 0.05). Heat stress increased the contents of carbonyl, advanced glycation end-products, malonaldehyde, and the activities of catalase, glutathione peroxidase, and total antioxidant capacity compared with the NC and PF groups (P < 0.05). Heat stress increased the contents of glucose and lactate, declined the glycogen content, and lowered the relative protein expressions of pyruvate kinase muscle type, lactate dehydrogenase A type (LDHA), and citrate synthase compared to those of the NC group (P < 0.05). In contrast to the NC and PF groups, heat stress intensified the carbonylation levels of phosphoglucomutase 1, triosephosphate isomerase 1, ß-enolase, and LDHA, which were positively correlated with the F/G (P < 0.05). These findings demonstrate that heat stress depresses growth performance on account of oxidative stress and glycolysis disorders. It further increases the carbonylation of glycolytic enzymes, which potentially correlates with the F/G by disturbing the mode of energy supply of broilers.

Efficacy of creatine nitrate supplementation on redox status and mitochondrial function in pectoralis major muscle of preslaughter transported broilers.

This study was purposed to investigate the efficacy of dietary creatine nitrate (CrN) supplementation on redox status and mitochondrial function in pectoralis major (PM) muscle of broilers that experienced preslaughter transport. A total of 288 Arbor Acres broilers (28-day-old) were randomly assigned into five dietary treatments, including a basal diet or the basal diet supplemented with 600 mg/kg guanidinoacetic acid (GAA), 300, 600, or 900 mg/kg CrN for 14 days, respectively. On the transportation day, the basal diet group was divided into two groups on average, resulting in six groups. The control group was transported for 0.5 h and the other groups for 3 h (identified as Control, T3h, GAA600, CrN300, CrN600, and CrN900 group, respectively), and all crates were randomly placed on the truck travelling at an average speed of 80 km/h. Our results showed that GAA600 and CrN treatments decreased the muscle ROS level and MDA content (P < 0.05) and increased the mitochondrial membrane potential (P < 0.001), as well as a higher mRNA expression of avUCP (P < 0.001) and lower mRNA expressions of Nrf2 (P < 0.001), Nrf2 and PGC-1α (P < 0.05) compared with T3h group. Meanwhile, the mRNA and protein expressions of Nrf1, TFAM, and PGC-1α in CrN600 and CrN900 groups were lower than those in the T3h group (P < 0.05). Conclusively, dietary supplementation with GAA and CrN decreased muscle oxidative products and enhanced mitochondrial uncoupling mechanism and mtDNA copy number, which relieved muscle oxidative damage and maintained mitochondrial function.

Mitochondrial dysfunction and calcium dyshomeostasis in the pectoralis major muscle of broiler chickens with wooden breast myopathy.

The incidence of wooden breast (WB) meat of commercial broiler chicken has been increasing in recent years. Histological examination found that the occurrence of WB myopathy was accompanied by the pectoralis major (PM) muscle damage. So far, the potential mechanisms are not fully understood. This study aimed to explore the underlying mechanism of the damage of WB-affected PM muscle caused by changes in mitochondrial function, mitochondrial redox status and Ca2+ homeostasis. A total of 80 market-age Arbor Acres male broiler chickens were sampled and categorized into control (CON) and WB groups based on the evaluation of myopathic lesions. PM muscle samples were collected (n = 8 in each group) for histopathological evaluation and biochemical analyses. Ultrastructural examination and histopathological changes suggested the occurrence of PM muscle damage in broiler chickens with WB myopathy. The WB group showed an increased level of reactive oxygen species and enhanced antioxidant capacities in mitochondria of PM muscle. These changes were related to impaired mitochondria morphology and mitochondrial dysfunction. In addition, abnormal expressions of Ca2+ channels led to substantial Ca2+ loss in SR and cytoplasmic Ca2+ overload, as well as Ca2+ accumulation in mitochondria, resulting in Ca2+ dyshomeostasis in PM muscle of broiler chickens with WB myopathy. Combined, these findings indicate that WB myopathy is related to mitochondrial dysfunction, mitochondrial redox status imbalance and Ca2+ dyshomeostasis, leading to WB-affected PM muscle damage.

Insight on the meat quality and carbonylation profile of breast muscle of broilers in response to chronic heat stress: A proteomic research.

This study was conducted to explore the influences of carbonyl modification on proteins within the breast muscle of heat-stressed broilers and their correlations to decreased meat quality. The results showed that birds that suffered from heat stress had higher lightness, drip loss, shear force value, and hardness, and lower redness and springiness of breast meat than those under normal control and pair fed treatments. Proteomic analysis identified a total of 921 differentially carbonylated sites, which were allocated to 419 proteins. The modified sites included Lys, Pro, Arg, Trp, Cys, His, and Met. Seven motif sequences were detected, where five motifs neighbored Lys and two neighbored Pro. The differentially carbonylated proteins in heat-stressed birds mainly participated in the glycolytic process, collagen fibril organization, calcium homeostasis, and apoptosis. This study provided a unique landscape of the muscular carbonyl modification rule and unraveled the potential impact of carbonylated protein on meat quality.

ß-FeOOH/TiO2/cellulose nanocomposite aerogel as a novel heterogeneous photocatalyst for highly efficient photo-Fenton degradation.

The photo-Fenton reaction provides an effective strategy for the removal of organic pollution in water environments. However, it remains a great challenge to develop photo-Fenton catalysts with high photocatalytic activity, low catalyst losses and excellent recyclability. In this work, a ß-FeOOH/TiO2/cellulose nanocomposite aerogel was fabricated as an efficient and convenient heterogeneous catalyst in the photo-Fenton system via in situ synthesis of TiO2 and ß-FeOOH NPs on a cellulose-based aerogel. The cellulose aerogel not only acted as a microreactor to prevent aggregation of particles, but also acted as a supporting material to improve the stability and reusable performance of the catalyst. Meanwhile, the synergy between TiO2 and ß-FeOOH endowed the cellulose-based nanocomposite aerogel with highly efficient photo-Fenton degradation of dyes. As a result, the composite ß-FeOOH/TiO2/cellulose aerogel displayed high photocatalytic performance. Its removal efficiency of MB reached 97.2% under weak UV light for 65 min. There is no obvious decrease in the catalytic efficiency after 5 cycles, suggesting the stability and recyclability of the composite aerogel. This study provides a novel strategy for the preparation of efficient green heterogeneous catalysts by using renewable resources, and shows composite catalyst processes have great potential in wastewater treatment.

Comparison of biochemical characteristics and gel properties of chicken myofibrillar protein affected by heme-iron and nonheme-iron oxidizing systems.

In this study, the effect of hemin and non-heme iron on the biochemical and gelling properties of chicken myofibrillar protein (MP) was compared. Results revealed that free radicals from hemin incubated MP were significantly higher than that in FeCl3 incubated samples (P < 0.05), and had higher ability to initiate protein oxidation. The carbonyl content, surface hydrophobicity, random coil increased with oxidant concentration, whereas the total sulfhydryl and α-helix content decreased in both oxidizing systems. The turbidity and particle size were increased after oxidant treatment, indicating oxidation promoted the cross-linking and aggregation of protein, and the degree of aggregation was higher in hemin treated MP compared with that incubated with FeCl3. The biochemical changes of MP resulted in an uneven and loose gel network structure, which significantly reduced the gel strength and water holding capacity (WHC) of the gel.

Intracellular Calcium Overload and Activation of CaMKK/AMPK Signaling Are Related to the Acceleration of Muscle Glycolysis of Broiler Chickens Subjected to Acute Stress.

The current study investigated the effect of preslaughter transport on stress response and meat quality of broilers and explored the underlying mechanisms involved in the regulation of muscle glycolysis through calcium/calmodulin-dependent protein kinase kinase (CaMKK)/AMP-activated protein kinase (AMPK) signaling. Results suggested that transport induced stress responses of broilers and caused PSE-like syndrome of pectoralis major muscle. Preslaughter transport enhanced the mRNA expressions of glycogen phosphorylase and glucose transporters, as well as the activities of glycolytic enzymes, which accelerated the breakdown of glycolytic substrates and the accumulation of lactic acid. In addition, acute stress induced abnormal intracellular calcium homeostasis by disrupting calcium channels on the cell membrane and sarcoplasmic reticulum, which led to the activation of CaMKK and promoted AMPK phosphorylation. This study provides evidence that the intracellular calcium overload and the enhancement of CaMKK/AMPK signaling are related to the accelerated muscle glycolysis of broiler chickens subjected to acute stress.

Chronic heat stress causes liver damage via endoplasmic reticulum stress-induced apoptosis in broilers.

Liver is a central metabolic organ, which is sensitive to heat stress. Liver damage affects animals' health and endangers the livestock and poultry industry. This study aimed to investigate the mechanism of chronic heat stress-induced liver damage in broiler chickens. Broilers were divided into 3 treatments: normal control group (NOR, 22°C), heat stress group (HS, 32°C) and pair-feeding group (PF, 22°C) for a 7-d and 14-d trial. The results showed that 7 d heat exposure caused microvesicular steatosis and reduced glutamine synthetase activity in broiler liver (P < 0.05). After 14 d of heat exposure, heat stress caused vacuolar degeneration and apoptosis in the liver; elevated liver relative weight and liver glutaminase activity as well as plasma ammonia level (P < 0.05). Additionally, heat stress enhanced GRP78 protein expression and the mRNA expressions of endoplasmic reticulum (ER) stress responses genes and apoptosis-related genes in broiler liver after 14 d of heat exposure (P < 0.05). In conclusion, chronic heat stress triggered ER stress-induced apoptosis and caused liver damage, which may compromise ammonia detoxification in broiler liver.

Transcriptome analysis reveals the mechanism of chronic heat stress on meat quality of broilers.

BACKGROUND: Chronic heat stress has a negative impact on poultry meat quality. Although this has been extensively investigated, previous studies have primarily focused on metabolic alterations and oxidative stress in the pectoralis major (PM) muscle under chronic heat stress, and not all of the underlying molecular mechanisms are completely understood. METHODS: A total of 144 male Arbor Acres broilers (28 d old) were randomly allocated into 3 treatment groups: (1) the normal control (NC) group, with broilers raised at 22 °C and fed a basal diet; (2) the heat stress (HS) group, with birds raised at 32 °C and fed a basal diet; and (3) the pair-fed (PF) group, with birds raised at 22 °C and fed the amount of feed equal to the feed consumed on the previous day by the HS group. The experiment lasted for 14 d. RESULTS: Chronic heat stress decreased the average daily feed intake and average daily gain, increased feed:gain ratio (P < 0.05); and increased drip loss, cooking loss, shear force, hardness, and decreased pH, redness (a*); and springiness of PM muscle (P < 0.05). Furthermore, chronic heat stress decreased muscle fiber density, increased connective tissue, and led to intracellular vacuolation. The transcriptome analyses indicated that the effect of chronic heat stress on meat quality was not only related to metabolism and oxidative stress, but also to signal transduction, immune system, transport and catabolism, cell growth and death, and muscle structure. CONCLUSIONS: Chronic heat stress has a negative impact on the growth performance, meat quality, and the PM muscle structure of broilers. Transcriptome analysis revealed a comprehensive understanding of the mechanism of the chronic heat stress-induced deterioration of broiler meat quality at the transcriptional level.

Dietary creatine nitrate enhances muscle creatine loading and delays postmortem glycolysis of broilers that experienced preslaughter transport.

This study investigated the attenuating effects of dietary creatine nitrate (CrN), a novel form of creatine, on energy expenditure and rapid glycolysis in pectoralis major (PM) muscle of broiler induced by preslaughter transport. A total of 288 Arbor Acres broilers (28 day old) were randomly assigned into five dietary treatments, including a basal diet or the basal diet supplemented with 600 mg/kg guanidinoacetic acid (GAA), 300, 600, or 900 mg/kg CrN for 14 d, respectively. On the day of transportation, the broilers from basal diet group were divided into two equal groups: one group was transported for 0.5 h (Control group) and the other group was transported for 3 h (T3h group). Meanwhile, the birds from GAA and CrN supplementation groups were transported for 3 h (identified as GAA600, CrN300, CrN600, and CrN900 group, respectively). The results demonstrated that dietary supplementation of GAA or CrN from 28 to 42 d of age did not significantly affect the growth performance, carcass traits, and textural characteristics (P > 0.05) in PM muscle of transported broilers. Compared with T3h group, GAA600, CrN600, and CrN900 groups increased the pH45min (P < 0.01), and CrN600, CrN900 groups decreased the cooking loss (P < 0.05) of PM muscle. Meanwhile, the muscle of GAA600, CrN600, and CrN900 groups showed a higher glycogen content (P < 0.01) and a lower lactic acid content (P < 0.01). GAA600 and all CrN treatments enhanced muscle Cr content and reduced AMP/ATP ratio (P < 0.01). In addition, GAA600 and all CrN treatments downregulated the relative mRNA expression levels of LKB1 and AMPKα2 (P < 0.001) and the protein expression of p-AMPKαThr172 compared with the T3h group (P < 0.01). All CrN treatments showed lower protein expression levels of LKB1 and p-LKB1Thr189 than those of the T3h group (P < 0.05). In summary, dietary supplementation with GAA and CrN enhanced the content of muscle creatine, and inhibited transport-induced activation of LKB1/AMPK pathway, which is beneficial for delaying rapid muscle glycolysis and improving meat quality.

Preslaughter transport has been reported to accelerate energy expenditure and induce rapid muscle glycolysis of broilers, resulting in inferior meat quality. This study investigates the attenuating effects of dietary creatine nitrate (CrN), a novel form of creatine, on energy expenditure and rapid glycolysis in pectoralis major (PM) muscle of broilers induced by preslaughter transport. The results revealed that dietary supplementation of 600 mg/kg guanidinoacetic acid (GAA), 300, 600, or 900 mg/kg CrN for 14 d prior to slaughter had no significant effect on the growth performance and carcass traits of transported broilers. However, dietary supplementation with 600 mg/kg GAA, 600, or 900 mg/kg CrN elevated creatine and phosphocreatine loading and inhibited transport-induced activation of LKB1/AMPK pathway in PM muscle, which is beneficial for delaying muscle glycolysis and improving meat quality.

Acute stress deteriorates breast meat quality of Ross 308 broiler chickens by inducing redox imbalance and mitochondrial dysfunction.

This study investigated the effects of acute stress on breast meat quality, redox status, and mitochondrial function in pectoralis major (PM) muscle of broilers. A total of 168 broiler chickens (42-d-old, Ross 308) were randomly divided into control (CON) and preslaughter transport (T) treatments. A broiler was an experimental unit. Each treatment consisted of 84 broilers, and they were put in 12 crates with 7 broilers each. Broilers in the T group were transported according to a designed protocol, and the CON broilers were kept in crates under normal living conditions before slaughtering. Based on the meat quality traits assessed at postmortem 24 h, all PM muscles of the transported broilers were further classified into normal (T-NOR) and pale, soft, and exudative (PSE)-like (T-PSE) groups for the determination of redox status in PM muscle and isolated mitochondria, energy metabolites, mitochondrial electron transport chain complexes activities, as well as mitochondrial function-modulating genes expression. Compared with CON, the extent of lipid peroxidation as well as protein oxidation were significantly increased in both PM muscles and mitochondria in T-PSE (P < 0.05), whereas not in T-NOR. Higher activities of glutathione peroxidase, total superoxide dismutase, and Cu-Zn superoxide dismutase were observed in PM muscle of T-NOR broilers when compared with CON (P < 0.05). Preslaughter transport increased the generation of reactive oxygen species, as well as enhanced antioxidant capacity in PM mitochondria of broilers (P < 0.05). Compared with CON, the ATP content, activities of complexes I and III, as well as relative mitochondrial membrane potential and swelling were significantly decreased in T-PSE (P < 0.05), whereas no significant changes in either ATP content or complex I activity were observed in T-NOR. Preslaughter transport enhanced the mRNA expression of regulators involved in the glutathione system, thioredoxin 2 system, and mitochondrial biosynthesis in PM muscle of broilers (P < 0.05). Moreover, we noticed a more evident enhancement effect in T-NOR than in T-PSE (P < 0.05). Overall, this work indicates that acute stress-induced redox imbalance and mitochondrial dysfunction have significant implications for the development of PSE-like meat.

Preslaughter acute stress can cause physiological and metabolic disorders of broilers and lead to deterioration of meat quality and high incidence of pale, soft, and exudative (PSE)-like meat, which block the development of broiler industry. Acute stress-induced imbalance of redox status and insufficient energy supply are important reasons for meat quality reduction. Mitochondria provide the overall cellular energy production through oxidative phosphorylation and play a key role in maintaining energy homeostasis. Investigating the effects of acute stress on mitochondrial function and exploring the possible mechanisms involved in mitochondrial function regulation can promote an understanding of how acute stress affects broiler meat quality. Our results indicate that pre-slaughter transport under high environmental temperature reduces energy status and induces oxidative stress in pectoralis major muscle of broilers, which contribute to the deterioration of meat quality and the increased occurrence of PSE-like meat. The oxidative damage of mitochondria and the dysregulation of mitochondrial function are responsible for the energy deficiency and redox imbalance. Although broilers improve the antioxidant capacity and enhance the biosynthesis as well as the decoupling of respiratory chain for maintaining mitochondrial function in response to acute stress, these adaptive responses are insufficient to restore mitochondrial homeostasis and redox status.

Oxidative stress impairs the meat quality of broiler by damaging mitochondrial function, affecting calcium metabolism and leading to ferroptosis.

OBJECTIVE: This work was conducted to investigate the effects of oxidative stress on meat quality, mitochondrial function, calcium metabolism and ferroptosis of broilers. METHODS: In this study, a total of 144 one-day-old male Ross 308 chicks were divided into 3 groups (control group, saline group, and hydrogen peroxide [H2O2] group) with 6 replicates of 8 broilers each. The study lasted for 42 d. The broilers in the saline and H2O2 groups were intraperitoneally injected with 0.75% saline and 10.0% H2O2 on the 16th and 37th day of the experimental period respectively, the injection volumes were 1.0 mL/kg of broiler body weight. On the 42nd day of the experimental period, two chicks were randomly selected from each cage, a total of thirty-six chicks were stunned by electric shock and slaughtered to collect breast muscle samples. RESULTS: The H2O2 exposure reduced pH value, increased drip loss and shear force of breast meat (p<0.05), impaired the ultrastructure and function of mitochondria. The H2O2 exposure damaged the antioxidant system in mitochondria, excessive reactive oxygen species carbonylation modified calcium channels on mitochondria, which impaired the activities of key enzymes on calcium channel, resulted in the increased calcium concentration in cytoplasm and mitochondria (p<0.05). In addition, the H2O2 exposure increased the iron content and lipid peroxidation (p<0.05), which induced ferroptosis. CONCLUSION: Oxidative stress could impair meat quality by causing mitochondrial dysfunction, resulting in calcium metabolism disorder and ferroptosis.

E-Commerce Fraud Detection Model by Computer Artificial Intelligence Data Mining.

This study aims to identify e-commerce fraud, solve the financial risks of e-commerce enterprises through big data mining (BDM), further explore more effective solutions through Information fusion technology (IFT), and create an e-commerce fraud detection model (FDM) based on IFT (namely, computer technology (CT), artificial intelligence (AI), and data mining (DM). Meanwhile, BDM technology, support vector machine (SVM), logistic regression model (LRM), and the proposed IFT-based FDM are comparatively employed to study e-commerce fraud risks deeply. Specifically, the LRM can effectively solve data classification problems. The proposed IFT-based FDM fuses different information sources. The experimental findings corroborate that the proposed Business-to-Business (B2B) e-commerce enterprises-oriented IFT-based FDM presents significantly higher fraud identification accuracy than SVM and LRM. Therefore, the IFT-based FDM is superior to SVM and LRM; it can process and calculate e-commerce enterprises' financial risk data from different sources and obtain higher accuracy. BDM technology provides an important research method for e-commerce fraud identification. The proposed e-commerce enterprise-oriented FDM based on IFT can correctly analyze enterprises' financial status and credit status, obtaining the probability of fraudulent behaviors. The results are of great significance to B2B e-commerce fraud identification and provide good technical support for promoting the healthy development of e-commerce.

Role of dietary resistant starch in the regulation of broiler immunological characteristics.

Resistant starch (RS) has received increased attention due to its potential health benefits. This study was aimed to investigate the effects of dietary corn RS on immunological characteristics of broilers. A total of 320 broiler chicks were randomly allocated to five dietary treatments: normal corn-soyabean (NC) diet group, corn starch diet group, 4 %, 8 % and 12 % RS diet groups. This trial lasted for 42 d. The relative weights of spleen, thymus and bursa, the concentrations of nitric oxide (NO) and IL-4 in plasma at 21 d of age, as well as the activities of total nitric oxide synthase (TNOS) and inducible nitric oxide synthase (iNOS) in plasma at 21 and 42 d of age showed positive linear responses (P < 0·05) to the increasing dietary RS level. Meanwhile, compared with the birds from the NC group at 21 d of age, birds fed 4 % RS, 8 % RS and 12 % RS diets exhibited higher (P < 0·05) relative weight of bursa and concentrations of NO and interferon-γ in plasma. Birds fed 4 % RS and 8 % RS diets showed higher (P < 0·05) number of IgA-producing cells in the jejunum. While compared with birds from the NC group at 42 d of age, birds fed 12 % RS diet showed higher (P < 0·05) relative weight of spleen and activities of TNOS and iNOS in plasma. These findings suggested that dietary corn RS supplementation can improve immune function in broilers.

Evaluation of cultivated land quality using attention mechanism-back propagation neural network.

Cultivated land quality is related to the quality and safety of agricultural products and to ecological safety. Therefore, reasonably evaluating the quality of land, which is helpful in identifying its benefits, is crucial. However, most studies have used traditional methods to estimate cultivated land quality, and there is little research on using deep learning for this purpose. Using Ya'an cultivated land as the research object, this study constructs an evaluation system for cultivated land quality based on seven aspects, including soil organic matter and soil texture. An attention mechanism (AM) is introduced into a back propagation (BP) neural network model. Therefore, an AM-BP neural network that is suitable for Ya'an cultivated land is designed. The sample is divided into training and test sets by a ratio of 7:3. We can output the evaluation results of cultivated land quality through experiments. Furthermore, they can be visualized through a pie chart. The experimental results indicate that the model effect of the AM-BP neural network is better than that of the BP neural network. That is, the mean square error is reduced by approximately 0.0019 and the determination coefficient is increased by approximately 0.005. In addition, this study obtains better results via the ensemble model. The quality of cultivated land in Yucheng District is generally good, i.e.,mostly third and fourth grades. It conforms to the normal distribution. Lastly, the method has certain to evaluate cultivated land quality, providing a reference for future cultivated land quality evaluation.

Risk Analysis of Textile Industry Foreign Investment Based on Deep Learning.

With the decline of China's economic growth rate and the uproar of antiglobalization, the textile industry, one of the business cards of China's globalization, is facing a huge impact. When the economic model is undergoing transformation, it is more important to prevent enterprises from falling into financial distress. So, the financial risk early warning is one of the important means to prevent enterprises from falling into financial distress. Aiming at the risk analysis of the textile industry's foreign investment, this paper proposes an analysis method based on deep learning. This method combines residual network (ResNet) and long short-term memory (LSTM) risk prediction model. This method first establishes a risk indicator system for the textile industry and then uses ResNet to complete deep feature extraction, which are further used for LSTM training and testing. The performance of the proposed method is tested based on part of the measured data, and the results show the effectiveness of the proposed method.

Oxidative stress induced by hydrogen peroxide promotes glycolysis by activating CaMKK/LKB1/AMPK pathway in broiler breast muscle.

Oxidative stress is common in the whole process of broiler production, and breast muscle is one of the target organs most vulnerable to oxidative attack. When broilers are subjected to oxidative stress, the regulation of adenosine 5-monophosphate activated protein kinase (AMPK) is a critical path to maintain the dynamic balance of intracellular energy. However, whether calcium/calmodulin-dependent protein kinase (CaMKK) and liver kinase B1 (LKB1) are involved in the regulation of AMPK activation in broiler breast muscle under oxidative stress has not been elucidated. In this study, a total of 144 one-day-old male Ross 308 chicks were selected, with an average body weight of 43.44 ± 0.04 g. The broilers were divided into 3 groups with 6 replicates of 8 broilers each (control group, intraperitoneal injection of physiological saline group, and intraperitoneal injection of hydrogen peroxide [H2O2] group), the injection time was selected on the 16th and 37th day of the experimental period, the injection volumes were 1.0 mL/kg broiler body weight. The results of this experiment showed that H2O2 exposure reduced the average daily gain (ADG) and increased the feed to gain ratio (F/G), the level of corticosterone (CORT) and the activity of lactate dehydrogenase (LDH) in serum were increased after H2O2 exposure. H2O2 exposure also increased the contents of reactive oxygen species (ROS) and protein carbonyl, but decreased the activities of catalase (CAT), total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) in breast muscle. After H2O2 exposure, the activity of pyruvate dehydrogenase (PDH) was decreased, the content of glycogen was reduced, and the contents of adenosine monophosphate (AMP) and lactate were increased in breast muscle. In addition, H2O2 exposure increased the content of Ca2+, upregulated the protein expression levels of CaMKK1 and p-AMPK, and increased the activities of hexokinase (HK) and LDH in breast muscle. These findings suggested that the activation of CaMKK/LKB1/AMPK signaling pathway would be associated with the accelerated glycolysis of broiler breast muscle under oxidative stress.

Preparation and characterization of gelatin/zein nanofiber films loaded with perillaldehyde, thymol, or ɛ-polylysine and evaluation of their effects on the preservation of chilled chicken breast.

Three edible food packaging films loaded with perillaldehyde (P), thymol (T), or ɛ-polylysine (ɛ-PL) in gelatin/zein (G/Z) nanofibers were prepared and characterized. Their effects on the preservation of chilled chicken breast were evaluated. Results showed that the addition of perillaldehyde, thymol, and ɛ-polylysine improved the morphology and diameter of the G/Z. Loading with perillaldehyde improved the elongation and tensile strength of the G/Z/P by 18% and 55%, respectively. The water vapor permeability and oxygen permeability of the G/Z/P were lower than those of the G/Z/T and G/Z/ɛ-PL. X-ray diffraction, differential scanning calorimetry suggested that perillaldehyde enhanced the thermal stability of the G/Z/P. Measurements of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), total volatile basic nitrogen, and total viable bacterial counts demonstrated that the G/Z/P had good bio-compatibility and effectively prolonged the shelf life of chilled chicken breasts by over 6 days. Therefore, the G/Z/P developed herein has potential application in chilled meat packaging.