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Superconductivity arises from the pairing of charge-eelectrons into charge-2ebosons—called Cooper pairs—and their condensation into a coherent quantum state. The exact mechanism by which electrons pair up into Cooper pairs in high-temperature superconductors is still not understood. One of the plausible candidates is that spin fluctuations can provide an attractive effective interaction that enables this1–3. Here we study the contribution of the electron–spin-fluctuation coupling to the superconducting state of the two-dimensional Hubbard model within dynamical cluster approximation4using a numerically exact continuous-time Monte Carlo solver5. We show that only about half of the superconductivity can be attributed to a pairing mechanism arising from treating spin fluctuations as a pairing boson in the standard one-loop theory. The rest of the pairing interaction must come from as-yet unidentified higher-energy processes.

Stress damage caused by early weaning and its possible mechanism have been studied mainly in young mammals, but rarely in altrices, especially in squabs. The study aimed to investigate the possible molecular mechanism of intestinal epithelial barrier damage caused by early weaning in squabs through determining the intestinal permeability, the ultrastructure of villous epithelium, the contents of ileal cytokines, and the protein relative expression of tight-junction proteins, TLRs and their mediated key factors in inflammatory signaling pathways. A total of 192 newly hatched squabs were randomly divided into 2 groups, 1 group was weaned and fed artificial pigeon milk from d 7, and the other group continued to be fed by the parent pigeons. The ileal mucosa and serum of 8 replicates were collected at 1, 4, 7, 10, and 14 d after weaning. The results indicated that early weaning could reduce the growth performance of squabs and damage the intestinal epithelial barrier, which is characterized by down-regulating the protein expression of claudin-1/3, up-regulating the protein expression of claudin-2, promoting the secretion of pro-inflammatory factors, inhibiting the secretion of anti-inflammatory factors, and increasing the permeability of the intestinal barrier. The specific mechanism of stress damage might be the activation of TLR2/4-MyD88-ERK/JNK inflammatory signaling pathway leading to the increase levels of IL-6 and TNF-α.

Selenium (i.e., Se) is a trace element that is vital in poultry nutrition, and optimal forms and levels of Se are critical for poultry productivity and health. This study aimed to compare the effects of sodium selenite (SS), yeast selenium (SY), and methionine selenium (SM) at selenium levels of 0.15 mg/kg and 0.30 mg/kg on production performance, egg quality, egg selenium content, antioxidant capacity, immunity and selenoprotein expression in laying hens. The trial was conducted in a 3 × 2 factorial arrangement, and a total of 576 forty-three-wk-old Hyland Brown laying hens were randomly assigned into 6 treatment groups, with diets supplemented with 0.15 mg Se/kg and 0.3 mg Se/kg of SS, SY and SM for 8 wk, respectively. Results revealed that SM increased the laying rate compared to SS and SY (P< 0.05), whereas different selenium levels had no effect. Organic selenium improved egg quality, preservation performance, and selenium deposition compared to SS (P< 0.05), while SY and SM had different preferences for Se deposition in the yolk and albumen. Also, organic selenium enhanced the antioxidant capacity and immune functions of laying hens at 0.15 mg Se/kg, whereas no obvious improvement was observed at 0.30 mg Se/kg. Moreover, SY and SM increased the mRNA expression of most selenoproteins compared to SS (P< 0.05), with SM exhibiting a more pronounced effect. Correlation analysis revealed a strong positive association between glutathione peroxidase 2 (GPx2), thioredoxin reductases (TrxRs), selenoprotein K (SelK), selenoprotein S (SelS), and antioxidant and immune properties. In conclusion, the use of low-dose organic selenium is recommended as a more effective alternative to inorganic selenium, and a dosage of 0.15 mg Se/kg from SM is recommended based on the trail conditions.

High energy diet are a risk factor for intestinal barrier damage. Butyrate, a major energy source for intestinal epithelial cells, has been shown to improve barrier dysfunction and modulate the gut microbiota. In this trial, we examined the preventative effect of coated sodium butyrate (CSB) on high-energy low-protein (HELP)-induced intestinal barrier injury in laying hens, and also worked to determine the underlying mechanisms by an integrative analysis of gut microbiota and the metabolome. A total of 216 healthy 28-weeks-old Huafeng laying hens were randomly assigned to 3 groups with 6 replicates each: the CON group (normal diet), HELP group (high-energy and low-protein diet) and CH500 group (500 mg/kg CSB added to HELP diet). The duration of the trial encompassed a period of 10 weeks. The results revealed that CSB treatment improved the laying rate (P<0.05) and mitigated the detrimental effects on intestinal barrier function and the inflammatory response induced by the HELP diet in laying hens (P<0.05). Microbial profiling analysis revealed that the CSB treatment reshaped the HELP-perturbed gut microbiota, and promoted the growth of beneficial bacteria (P<0.05). Untargeted metabolomics analysis revealed that CSB reduced the metabolites associated with intestinal inflammation (P<0.05). In conclusion, CSB did not merely modulate alterations in the gut microbiota composition and microbial metabolites but also yielded increased egg production, while mitigating intestinal barrier dysfunction and inflammatory responses induced by HELP in laying hens.

Our previous study found that early weaning is associated with decreased growth performance, intestinal barrier impairment, and an imbalance in Th17/Treg in pigeon squabs. Chitosan oligosaccharides (COS) has been substantiated to regulate gut microbiota and restore Th17/Treg equilibrium in mammals, thereby ameliorating growth performance. However, the potential effects of COS in altricial birds remain unclear. 300 healthy 7-day-old American king pigeon squabs were selected with similar body weights and randomly divided into 5 groups. The 5 treatment groups were as follows: the control group (CON), fed with artificial pigeon milk; four supplementation groups, fed with artificial pigeon milk +100 (COS1), 150 (COS2), 200 (COS3), and 250 (COS4) mg/kg COS, respectively. Results showed that dietary supplementation of COS significantly enhanced the growth performance of weaned squabs. Compared to the CON group, the COS groups exhibited increased villus length and villus area in the jejunum and ileum, accompanied by improvements in morphological structure and mucosal permeability. COS was found to reduce the levels of Th17-associated cytokines and increase the levels of Treg-associated cytokines. COS downregulated the expression of retinoic acid receptor-related orphan receptor C (RORC), a key transcription factor of Th17 cells, while upregulated the expression of Forkhead box protein P3 (FOXP3), a key transcription factor of Treg cells. Dietary COS supplementation increased gut bacterial diversity, altered the relative abundance of several bacteria taxa and enhanced the concentration of short-chain fatty acids (SCFAs). Correlation analysis demonstrated a close association between gut microbiota, SCFAs, and indicators related to the Th17/Treg balance. Moreover, we found that SCFAs correlated more strongly with Th17/Treg-related indexes than gut microbiota. These results demonstrated that COS could relieve early weaning stress in pigeon squabs and the optimal dosage of dietary COS supplementation was suggested to be 200mg/kg. In addition, COS had a protective effect on maintaining intestinal immune balance by modulating microbiota and Th17/Treg related signaling pathways, in which SCFAs might play a crucial role as messengers.

AbstractThe present study was conducted to investigate the effects of coated sodium butyrate (CSB) on production performance, egg quality, serum biochemistry, digestive enzyme activity, intestinal health of laying hens. 720 hens at 52 weeks were assigned in five groups including basal diet (control) and a basal diet supplemented with 250, 500, 750, and 1000 mg/kg CSB for 8 weeks. The results showed that the 500 mg/kg CSB group increased laying rate but 500 and 750 mg/kg groups decreased feed conversion ratio (p < .05). At the fourth week, dietary CSB at more than or equal to 500 mg/kg level increased the Haugh unit (p < .01); At the eighth week, 500 and 1000 mg/kg CSB groups improved the eggshell strength, Haught unit and albumen height (p < .05). Dietary CSB administration except for the 250 mg/kg group increased the serum albumin and calcium and decreased the triglyceride content (p < .05). 500 and 750 mg/kg CSB groups increased the activities of trypsin and amylase in the pancreas and duodenum (p < .05). The groups of 500 and 750 mg/kg increased the villus height and villus height to crypt depth ratio (V/C) in the jejunum and ileum (p < .05). In the jejunum, at more than or equal to 500 mg/kg CSB groups increased the expressions of ZO-1 and Occludin (p < .05); In the ileum, 500 and 750 mg/kg CSB groups increased the expressions of claudin-1 and occludin and ZO-2 (p < .05). Conclusively, dietary supplementation of CSB can improve egg production, egg quality, digestive enzyme activity and present a positive effect on improving villi and intestinal mechanical barrier function.HIGHLIGHTSA significant improvement in production performance and egg quality was observed in birds fed diet with coated sodium butyrate.Administration of coated sodium butyrate enhanced protein and mineral availability and lipid metabolism of serum.Supplementation of coated sodium butyrate presented a positive impact on regulating intestinal health.

AbstractThe effects of chitooligosaccharide (COS) supplementation in laying hen diets on egg production, egg quality, blood biochemistry, antioxidant capacity and immunity during the late laying period were investigated in this 10-week trial. A total of 3000 Fengda No.1 laying hens, 52 weeks of age, were randomly allocated to three treatment groups, each of which included five replicates of 200 hens. Treatments consisted of the basal diet only or the basal diet supplemented with COS at 75 or 125 mg/kg. Hens fed with both COS supplemented diets had improved hen-day egg production, egg mass and feed conversion ratio than control birds. The higher level of COS supplementation exerted positive effects on eggshell strength and eggshell thickness, but significantly decreased yolk colour. Addition of 125 mg/kg COS was also found to significantly increase serum albumin content and significantly decrease serum cholesterol level. Dietary supplementation with COS significantly decreased serum triglyceride level compared with birds fed the control diet. Moreover, COS significantly increased total antioxidative capacity and significantly decreased malondialdehyde level in serum, but had no significance on the activities of antioxidant enzymes. The only change in blood immune response compounds observed in this study was a significantly increased concentration of C3 when laying hens were fed COS supplemented diets. In conclusion, COS could improve laying performance and egg quality in hens during the late laying period. Inclusion of COS in the diet might be beneficial to hens’ health by lowering serum lipids, enhancing antioxidant activity and slightly enhancing immune ability.HIGHLIGHTSCOS improved laying performance and egg quality in hens during the late laying period.Inclusion of COS in the diet might be beneficial to hens’ health by lowering serum lipids, enhancing the antioxidant activity and slightly enhancing immune ability.The optimum concentration of COS is 75 mg/kg in the basal diet in order to achieve an increased egg production, egg quality and health condition.

This study was undertaken to assess the effect of various levels of intramuscular fat (IMF: <0.5%, 0.5–0.99%, 1.0–1.49%, 1.5–1.99%, 2.0–2.49%, and >2.5%) on the physical meat quality of partridge. Physical characteristics such as moisture, pH, shear force, water-holding capacity (WHC), and color, along with IMF, were measured on 414 partridges (pectoral muscle). In this study, partridge meat was described as a kind of tender and moderately juicy meat with a nice color. Additionally, tenderness was significantly different between IMF < 0.5% and IMF > 0.5% levels (P< 0.01). IMF >0.5% also obtained higher value of WHC than IMF <0.5% although the difference was statistically nonsignificant. IMF levels did not affect pH or color. The results showed that IMF content was not significantly correlated with physical meat quality. However, in terms of eating experience, the minimum IMF level for better meat quality for consumer was 0.5%.

ABSTRACTThis study aimed to evaluate the anti-post-weaning diarrhoea effect of a low dose coated-ZnO in weaned piglets in relation to intestinal permeability. A total of 72 cross-bred piglets, weaned at 27 d, were allocated to three dietary treatments as follows: basal diet without supplemental ZnO (control group); basal diet supplemented with 2250 mg/kg ZnO (ZnO group); basal diet supplemented with 562.5 mg/kg coated-ZnO (C-ZnO group). The trial lasted 21 days. Compared with control group, supplementation with coated-ZnO reduced (P< .05) diarrhoea index, plasma D-lactate level, and improved (P< .05) jejunal villus height and the expression of occludin and zonula occludens protein-1 in jejunal mucosa. In the C-ZnO group, intestinal total antioxidant capacity was enhanced (P< .05), and levels of malondialdehyde were decreased (P< .05) compared with the control group. The apoptotic index of intestinal epithelial cell was decreased (P< .05). Furthermore, the effects of the low dose coated-ZnO were similar to the high dose ZnO on the aforementioned parameters. Our results indicated that the low dose of coated-ZnO can alleviate diarrhoea by decreasing intestinal permeability as does a pharmacological dose of ZnO.

ABSTRACTIn this study, nine non linear growth curve models were used to determine the goodness of fit by the body weight measurements of the total number of 178 partridges(Alectoris chukar), 93 females, and 85 males, respectively. The R2(coefficients of determination) values for the total partridges, females and males in Brody, Gompertz, Logistic, von Bertalanffy, asymptote regression,exponential, Monomolecular, Richards and Weibull-type were 0.985, 0.980 and 0.984, 0.997, 0.998 and 0.998, 0.996, 0.999 and 0.999, 0.995, 0.995 and 0.996, 0.985, 0.980 and 0.984, 0.891, 0.871 and 0.892, 0.985, 0.980 and 0.984, 0.997, 0.999 and 0.999, 0.997, 0.999 and 0.999, respectively. The R2values for Gompertz, Logistic, von Bertalanffy, Richards and Weibull-type were >0.99, while the exponential (<0.90) had the lowest. What’s more, the Gompertz, Logistic, Richards and Weibull-type models best described the data because of lower MSE (mean square error), AIC(Akaike’s information criteria) and BIC(Schwarz Bayesian information criterion), higher adj. R2(Adjusted coefficient of determination) and r(the correlation coefficient between measured body weight and estimated body weight) and there was not an autocorrelation between the residual values. As a result, based on goodness of fit criteria; R2, adj.R2, MSE, r, AIC, BIC values, the Weibull-type model best described live weight data of the Partridges(Alectoris chukar).

The study aimed to investigate whether linoleic acid could improve the intestinal barrier function of squabs under weaning stress conditions. Totally 320 7-d-old weaned squabs were randomly divided into four treatment groups, including control group (CON), 0.7% linoleic acid addition group (LA007), 1.4% linoleic acid addition group (LA014) and 2.1% linoleic acid addition group (LA021). At 21 d, eight squabs were randomly selected from each treatment group for sampling and determination. The results showed that adding linoleic acid could improve (P< 0.05) the body weight of weaned squabs, and LA014 had the best effect. With the increase of linoleic acid dosage, villi height and villi area increased linearly or quadratically (P< 0.05), and reached the maximum in LA021 or LA014, respectively. The linoleic acid supplementation could improve the intestinal tight junction of weaned squabs, and the LA014 was the most significant (P< 0.05). With the linoleic acid increasing, the levels of intestinal IL-6 and TNF-α decreased linearly (P< 0.05), while intestinal IL-10 increased quadratically (P< 0.05) and reached the maximum in LA014. Serum endotoxin and diamine oxidase levels decreased linearly (P< 0.05) and reached the lowest level in LA014. The ultrastructure of villi revealed that the length of ileal microvilli in LA014 was significantly increased (P< 0.05) and the microvilli became dense, and the mitochondria in epithelial cells returned to normal state. Further exploring the mechanism of linoleic acid alleviating intestinal injury caused by weaning stress in squabs, it was found that linoleic acid down-regulated (P< 0.05) the relative protein expression of TLR4, MyD88, phosphorylated JNK, and phosphorylated p38, reducing secretion of pro-inflammatory factors IL-6 and TNF-α. This study indicated that linoleic acid could alleviate intestinal barrier injury of early weaned squabs by down-regulating TLR4-MyD88-JNK/p38-IL6/TNF-α pathway.Under weaning stress conditions, linoleic acid could improve the intestinal villus development, strengthen the tight junction, decrease intestinal permeability, and promote the anti-inflammatory factor secretion.Linoleic acid supplementation could be applied as a means of nutrition regulation to alleviate the intestinal barrier damage caused by early weaning stress in pigeon squabs, reducing the occurrence of intestinal diseases in squabs.Artificial feeding of early weaned squabs can reduce the burden of breeding pigeons and shorten the breeding cycle. However, similar to early weaned mammals, early weaned squabs would also inevitably undergo severe physiological and psychological stress responses in the early stage. The growth performance and immunity of early weaned squabs were inferior to those of the parent feeding squabs. Previous studies suggest that linoleic acid played an important role in the growth and development of squabs. Therefore, the study aimed to investigate whether linoleic acid could improve the intestinal barrier function of squabs under weaning stress conditions. Totally 320 7-d-old weaned squabs were randomly divided into four treatment groups, including control group and linoleic acid addition groups with three different doses. At 21 d, eight squabs were randomly selected from each treatment group for sampling and determination. The results indicated that under weaning stress conditions, linoleic acid could weaken the inflammatory response, and alleviate the intestinal epithelial barrier damage of weaned squabs, specifically by promoting the development of intestinal villi, strengthening the tight junction, reducing intestinal permeability, and promoting the secretion of anti-inflammatory factors.

The study was aimed to evaluate the morphology and immune function development of the jejunum and ileum in squab pigeons (Columba livia), by determining the villus ultrastructure, secretory IgA, and cytokines. Eight squabs were randomly selected and sampled on the day of hatch (DOH), d 7 (D 7), 14 (D 14), and 21 (D 21) post-hatch, respectively. The results showed that under transmission electron microscope, the enterocyte circumference in jejunum and ileum decreased with age. The tight junction involved in enterocyte circumference of jejunal villi plateaued from D 7, whereas that of ileal villi changed irregularly. The microvilli of jejunal and ileal villi was maximum at D 14. Under scanning electron microscope, the villus morphology of jejunum and ileum appeared finger-shaped at DOH. After D 7, the jejunal villi were still finger-shaped whereas the ileal villi were leaflike. The secretory IgA in jejunum was significantly increased at D 21. The TGF-β decreased linearly in jejunum and ileum. The anti-inflammatory cytokines increased linearly and proinflammatory cytokines decreased linearly in jejunum and ileum with age. In conclusion, the morphological changes of jejunal epithelium were concentrated at DOH–D 7 and ileal epithelium at DOH–D 14 mainly. The changes in mucus layer and immune-related factors of jejunum and ileum persisted for almost the entire period.

Practical methods for preventing embryotoxicity in chickens that are caused by aflatoxin-B1 (AFB1) are currently rare. Binding absorbers are commonly used in feeding stuff to reduce laying hens' exposure to off-contaminated diets, thus reducing residue exposure to fertilized eggs. Nonetheless, several adsorbents have been shown to affect the use of nutrients and the absorption of minerals in poultry. Thus, seeking an effective strategy to counter or control embryotoxicity in broiler chicks caused by AFB1 is a problem. A total of 180 embryonated eggs were injected with 36 ng AFB1 with or without 5.90 mg L-methionine (Met) 30 embryonated eggs each, followed by incubation in an incubator until hatching time. The in ovo injection of Met significantly reduced toxicity caused by AFB1 in broiler embryos by enhancing the liver and kidney functions, lipid profiles, and alleviated oxidative stress during the incubation period. Furthermore, the relative gene expressions (SSTR5, TSH-β, Bcl-2, GSH-Px, GST-a, and SOD in the liver) were up-regulated with in ovo injection of AFB1+Met compared to AFB1 alone. Moreover, there was a dowin-regulated trend in Bax, Caspases-3, Caspases-7, Caspases-9, CYP1A1, CYP2H1, and P53 gene expression with in ovo injection of AFB1+Met compared to AFB1 alone. The in ovo injection of Met led to less apoptotic cells in liver tissues. Such results might be necessary for the poultry industry as it is focused on managing the embryotoxicity of AFB1, which affecting poultry production and welfare. Results from this study demonstrated that in ovo Met injection could alleviate AF-induced toxicity in chicken embryos.

Reasonable construction of sulfur host with high conductivity, large sulfur storage gap, strong chemical adsorption, and fast oxidation-reduction kinetics of polysulfide is very significant for its practical use in lithium-sulfur batteries (LSBs). In this paper, the surface modification of MIL-88A(Fe) is carried out by Dawson-type polyoxometalate (POM), and a hollow capsule shell material with P2W18, Fe3O4, and C components is synthesized by the subsequent carbonization process. When applied as the sulfur host, the hollow capsule shell material can efficiently improve the conductivity of sulfur electrode and restrain the volumetric change of active sulfur while charging and discharging. On this foundation, electrochemical analysis and density functional theory (DFT) calculation show that the P2W18on the outer layer of the capsule shell have effective electrocatalytic activity and potent chemical bond on the lithium polysulfides (LiPSs), which is helpful to block the shuttle effect. Therefore, the as-assembled LSBs display the outstanding specific capacity and prominent cycle stability. Specifically, it delivers an excellent reversible capacity of 1063 mAh/g after 100 cycles of charge–discharge at a rate of 0.5 C, accounting for a preservation by 96% in comparison to that of the initial cycle. Moreover, even after 2000 cycles at 1 C, the reversible specific capacity of 585 mAh/g can still be maintained with an average decay rate of only 0.021%.

In this study, we identified cadmium (Cd) as a potential endocrine disruptor that impairs laying performance, egg quality, and eggshell deposition and induces oxidative stress and inflammation in the eggshell glands of laying hens. A total of 480 38-wk-old laying hens were randomly assigned into 5 groups that were fed a basal diet (control) or a basal diet supplemented with Cd (provided as CdCl2·2.5 H2O) at 7.5, 15, 30, and 60 mg Cd per kg feed for 9 wk. The results showed that, when compared with the control group, a low dose of dietary Cd (7.5 mg/kg) had positive effects on egg quality by improving albumen height, Haugh unit, yolk color, and shell thickness at the third or ninth week. However, with the increase in the dose and duration of Cd exposure, the laying performance, egg quality, and activities of eggshell gland antioxidant enzymes (catalase [CAT], glutathione peroxide [GSH-Px]), and ATPase (Na+/K+-ATPase, Ca2+-ATPase, and Mg2+-ATPase) deteriorated, and the activity of total nitric oxide synthase (T-NOS) and the level of malondialdehyde (MDA) increased significantly (P < 0.05). The histopathology and real-time quantitative PCR results showed that Cd induced endometrial epithelial cell proliferation accompanied by upregulation of the mRNA levels of progesterone receptor (PgR) and epidermal growth factor receptor (EGFR), downregulation of the mRNA levels of estrogen receptor a (ERa) and interleukin 6 (IL6), and inflammation of the eggshell gland accompanied by significantly increased expression of complement C3 and pro-in?ammatory cytokine tumor necrosis factor a (TNFa) (P < 0.05). In addition, the ultrastructure of the eggshell showed that dietary supplementation with 7.5 mg/kg Cd increased the palisade layer and total thickness of the shell, but with the increase in dietary Cd supplementation (30 and 60 mg/kg) the thickness of the palisade layer and mammillary layer decreased significantly (P < 0.05), and the outer surface of the eggshell became rougher. Correspondingly, the expression of calbindin 1 (CALB1), ovocalyxin-32 (OCX-32), ovocalyxin-36 (OCX-36), osteopontin (SPP1), and ovocledidin-17 (OC-17) decreased significantly (P < 0.05) with increasing dietary Cd supplementation. Conclusively, the present study demonstrates that dietary supplementation with Cd negatively affects laying performance, egg quality, and eggshell deposition by disturbing the metabolism of eggshell glands in laying hens but has a positive effect on egg quality at low doses.