Background Caffeic acid(CA)and its derivative,chlorogenic acid(CGA),have shown promise in preventing and alleviating fatty liver disease.CA,compared to CGA,has much lower production costs and higher bioavailability,ma...Background Caffeic acid(CA)and its derivative,chlorogenic acid(CGA),have shown promise in preventing and alleviating fatty liver disease.CA,compared to CGA,has much lower production costs and higher bioavailability,making it a potentially superior feed additive.However,the efficacy,mechanistic differences,and comparative impacts of CA and CGA on fatty liver disease in laying hens remain unclear.This study aimed to evaluate and compare the effects of CA and CGA on production performance,egg quality,and fatty liver disease in laying hens.Results A total of 1,44061-week-old Hyline Brown laying hens were randomly divided into 8 groups and fed diets supplemented with basal diet,25,50,100 and 200 mg/kg of CA,and 100,200 and 400 mg/kg of CGA(CON,CA25,CA50,CA100,CA200,CGA100,CGA200 and CGA400,respectively)for 12 weeks.Both CA and CGA improved production performance and egg quality,while reducing markers of hepatic damage and lipid accumulation.CA and CGA significantly decreased TG,TC,and LDL-C levels and increased T-SOD activity.Transcriptomic and proteomic analyses revealed that CA and CGA reduced hepatic lipid accumulation through downregulation of lipid biosynthesis-related genes(ACLY,ACACA,FASN,and SCD1)and enhanced lipid transport and oxidation genes(FABPs,CD36,CPT1A,ACOX1,and SCP2).Of note,low-dose CA25 exhibited equivalent efficacy to the higher dose CGA100 group in alleviating fatty liver conditions.Mechanistically,CA and CGA alleviated lipid accumulation via activation of the ADPN-AMPK-PPARαsignaling pathway.Conclusions This study demonstrates that dietary CA and CGA effectively improve laying performance,egg quality,and hepatic lipid metabolism in laying hens,with CA potentially being more economical and efficient.Transcriptomic and proteomic evidence highlight shared mechanisms between CA25 and CGA100.These findings provide a foundation for CA and CGA as therapeutic agents for fatty liver disease and related metabolic diseases in hens,and also offer insights into the targeted modification of CGA(including the isomer of CGA)into CA,thereby providing novel strategies for the efficient utilization of CGA.Highlights(1)Dietary CA and CGA improve fatty liver,laying performance and egg quality.(2)Lower dose of CA25 achieves the equivalent improvement as CGA100 or CGA200.(3)CA and CGA mediate the ADPN-AMPK-PPARαpathway to alleviate fatty liver.展开更多
The low egg production of goose greatly limits the development of the industry.China possesses the most abundant goose breeds resources.In this study,genome resequencing data of swan goose(Anser cygnoides)and domestic...The low egg production of goose greatly limits the development of the industry.China possesses the most abundant goose breeds resources.In this study,genome resequencing data of swan goose(Anser cygnoides)and domesticated high and low laying goose breeds(Anser cygnoides domestiation)were used to identify key genes related to egg laying ability in geese and verify their functions.Selective sweep analyses revealed 416 genes that were specifically selected during the domestication process from swan geese to high laying geese.Furthermore,SNPs and Indels markers were used in GWAS analyses between high and low laying breed geese.The results showed that RTCB,BPIFC,SYN3,SYNE1,VIP,and ESR1 may be related to the differences in laying ability of geese.Notably,only ESR1 was identified simultaneously by GWAS and selective sweep analysis.The genotype of Indelchr3:54429172,located downstream of ESR1,was confirmed to affect the expression of ESR1 in the ovarian stroma and showed significant correlation with body weight at first egg and laying frequency of geese.CCK-8,EdU,and flow cytometry confirmed that ESR1 can promote the apoptosis of goose pre-hierarchical follicles ganulosa cells(phGCs)and inhibit their proliferation.Combined with transcriptome data,it was found ESR1 involved in the function of goose phGCs may be related to MAPK and TGF-beta signaling pathways.Overall,our study used genomic information from different goose breeds to identify an indel located in the downstream of ESR1 associated with goose laying ability.The main pathways and biological processes of ESR1 involved in the regulation of goose laying ability were identified by cell biology and transcriptomics methods.These results are helpful to further understand the laying ability characteristics of goose and improve the egg production of geese.展开更多
The evaluation of toxicity related to polychlorinated dibenzo-p-dioxins and furans(PCDD/Fs)and dioxin-like polychlorinated biphenyls(DL-PCBs)is crucial for a comprehensive risk assessment in real-world exposure scenar...The evaluation of toxicity related to polychlorinated dibenzo-p-dioxins and furans(PCDD/Fs)and dioxin-like polychlorinated biphenyls(DL-PCBs)is crucial for a comprehensive risk assessment in real-world exposure scenarios.This study employed a controlled feeding experiment to investigate the metabolic effects of dioxin-like compounds(DLCs)on laying hens via feed exposure.Diets enriched with two concentrations(1.17 and 5.13 pg toxic equivalents(TEQ)/g dry weight(dw))were administered over 14 days,followed by 28 days of clean feed.Metabolomics analyses of blood samples revealed significant metabolic variations between PCDD/Fs and DL-PCBs exposed groups and controls,reflecting the induced metabolic disruption.Distinct changes were observed in sphingosine,palmitoleic acid,linoleate,linolenic acid,taurocholic acid,indole acrylic acid,and dibutyl phthalate levels,implying possible connections between PCDD/Fs and DL-PCBs toxic effects and energy-neuronal imbalances,along with lipid accumulation and anomalous amino acid metabolism,impacting taurine metabolism.Moreover,we identified three differential endogenous metabolites—L-tryptophan,indole-3-acetaldehyde,and indole acrylic acid—as potential ligands for the aryl hydrocarbon receptor(AhR),suggesting their role inmediating PCDD/Fs and DL-PCBs toxicity.This comprehensive investigation provides novel insights into the metabolic alterations induced by PCDD/Fs and DL-PCBs in laying hens,thereby enhancing our ability to assess risks associated with their exposure in human populations.展开更多
Background Systemic inflammatory responses and oxidative stress occur in laying hens during the aging process,particularly during the post-peaking laying period,which generally result in multi-organ damages,leading to...Background Systemic inflammatory responses and oxidative stress occur in laying hens during the aging process,particularly during the post-peaking laying period,which generally result in multi-organ damages,leading to significant declines in egg performance and quality.Chlorogenic acid(CGA)-enriched extract from Eucommia ulmoides leaves has anti-inflammatory and antioxidant activities.However,the mechanisms underlying whether and how CGA alleviates systemic inflammatory responses and oxidative stress to improve egg performance and quality in postpeaking laying hens remain unclear.In this study,the potential regulatory mechanisms of CGA in alleviating inflammatory responses and oxidative stress along the gut-liver axis were investigated.A total of 36055-week-old Hy-line white-laying hens were randomly selected and divided into four groups.The hens in the four groups were fed a basal diet(CON)or basal diets supplemented with 200,400,and 800 mg/kg of CGA(CGA200,CGA400,and CGA800,respectively)for 10 weeks.Results The results demonstrated that CGA significantly alleviated intestinal and hepatic damages resulting from systemic inflammatory responses and oxidative stress,thereby improving the laying performance and egg quality of post-peaking laying hens.CGA reduced systemic inflammation by improving intestinal barrier function and modulating inflammation-associated microbiota(Blautia and Megamonas),thus inhibiting endotoxin translocation.CGA can also reduce oxidative stress by upregulating the NRF-2 pathway-related genes and increasing antioxidant enzyme activities in the liver.The results of transcriptome sequencing revealed that CGA promoted lipid metabolism by regulating hepatic adipocytokine pathway-related genes/protein and reduced the inflammatory responses and apoptosis in liver by regulating PI3K/AKT pathway-related genes/proteins,which was also verified by qPCR and western blotting.Conclusion CGA alleviated multi-organ damages and dysfunction by suppressing the systemic inflammatory responses and oxidative stress in post-peaking laying hens,thereby improving egg performance and quality.The optimal dose of CGA is 400 mg/kg in this experiment.These results provide a sound theoretical basis for the application of CGA as an exogenous animal feed additive for laying hens.展开更多
This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the...This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the effects.A total of 288 Hy-Line Brown layers were randomly assigned into 3 treatments and respectively offered soybean meal(SBM)-based diet,LCSM-based diet,and LCSM-based diet supplemented with 0.435%L-Ser.Dietary Ser supplementation reversed the decrease in quality indices of albumen,including the proportion of thick albumen(P<0.05),thick-to-thin ratio(P<0.05),albumen height(P<0.05),Haugh unit(P<0.05),and apparent viscosity that were caused by LCSM intake.Also,dietary Ser supplementation mitigated the LCSM-induced reduction in ovomucin content of the albumen(P<0.05).FT-IR analysis of ovomucin revealed differences in second derivative spectra at 1,200-800 cm^(-1) between birds received SBM-and LCSM-based diets,meanwhile,the α-helix of ovomucin was decreased by LCSM but increased by Ser addition(P<0.05).Furthermore,Ser addition up-regulated the mRNA expression of β-ovomucin in magnum mucosa at 2 and 7.5 h post-oviposition(P<0.05).Ser mitigated the LCSMinduced impairment of magnum epithelium,increased goblet cell counts(P<0.05),and up-regulated the expression of occludin,mucin 2,and the relevant glycosyltransferases for O-glycosylation in magnum mucosa(P<0.05).Conclusively,the alleviating effect of Ser on declining albumen quality due to dietary LCSM,could be explained by the efficacy of Ser in regulating ovomucin synthesis.This regulation occurred at the levels of transcription and posttranscriptional O-glycosylation modification ofβ-ovomucin,while positive effect on magnum morphology and barrier function could also in part account for the ovomucin content.This would provide a promising research direction on the adoption of nutritional interventions for manipulation of egg white quality from perspectives of albumen protein synthesis.展开更多
Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation a...Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation and minimal toxicity.Selenium-enriched yeast(SeY)is a well-established source,while selenium-enriched lactobacilli(SeL),a newer alternative,offers the added benefits of probiotics.This study examined the effects of SeY and SeL on egg quality,antioxidant capacity,Se deposition,and gut health in laying hens.After a two-week pre-treatment with a Sedeficient diet(SeD),450 Hy-Line Brown laying hens(30-week-old)were assigned into five dietary groups with six replicates of 15 hens each.The groups included a SeD,SeD supplemented with 1.5 mg Se/kg from SeY(SeY15),or 1.5,3.0,and 6.0 mg Se/kg from SeL(SeL15,SeL30,SeL60).The feeding trial lasted for 12 weeks.Results SeY15 and SeL15 improved the feed-to-egg ratio(P<0.05)in the latter stages.Haugh units were significantly increased(P<0.05)in the SeY15 and SeL30 groups,while darker yolk color(P<0.05)was observed in the SeY15,SeL15,and SeL60 groups.All Se-supplemented diets increased Se content in whole eggs,albumen,and yolk(P<0.05),while SeL groups showed a dose-dependent effect.Antioxidant enzyme activities increased,and MDA content decreased in the serum(P<0.05),with SeY15 showing the highest GSH-Px levels(P<0.05).SeL60 increased serum alkaline phosphatase and aspartate transaminase,and distorted the liver architecture(P<0.05).Se-diets reduced concentrations of reactive oxygen species(ROS)in the ileum and liver(P<0.05).SeL15 improved the ileal villus height-tocrypt depth ratio(P<0.05).SeY15 and/or SeL15 up-regulated TXNRD1 and SEPHS1 mRNA while down-regulating SCLY expression in the liver.SeY15 altered ileal microbiota by increasing both beneficial and pathogenic bacteria,whereas SeL15 predominantly boosted beneficial bacteria.Conclusion SeL integrates the antioxidant properties of organic Se with the probiotic benefits on gut health,resulting in a performance-enhancing effect comparable to that of SeY.However,high SeL level(6.0 mg Se/kg)compromised productivity and metabolic functions while enhancing Se deposition.展开更多
Background Uterine aging is a key factor contributing to the deterioration of egg quality and reproductive performance in laying hens.Despite its importance,the molecular mechanisms underlying uterine aging remain poo...Background Uterine aging is a key factor contributing to the deterioration of egg quality and reproductive performance in laying hens.Despite its importance,the molecular mechanisms underlying uterine aging remain poorly defined.This study aimed to characterize gene expression and regulatory changes associated with uterine aging in hens at different life stages.Results Transcriptomic Analysis of uterine tissue from hens aged 350,500,And 700 d revealed dynamic changes in gene expression patterns during aging.A significant upregulation of genes involved in cellular senescence was observed,including increased expression of the p53 signaling pathway And markers associated with inflammation And cell cycle arrest.The most notable changes occurred between 350 And 500 d of age,suggesting this as a critical window for the onset of uterine aging.MicroRNA sequencing identified miR-210a-5p as significantly reduced with age.Target prediction and experimental validation showed that miR-210a-5p directly suppresses the expression of RASL11B,a Ras-like small GTPase that activates the MAPK signaling pathway.In primary uterine epithelial cells,reduced miR-210a-5p levels led to elevated RASL11B expression,increased activation of B-Raf,MEK,and ERK proteins,and enhanced expression of aging-related genes and inflammatory factors.In contrast,overexpression of miR-210a-5p or inhibition of the MAPK pathway delayed senescence and reduced inflammatory signaling.RASL11B overexpression was sufficient to induce aging phenotypes,confirming its central role in promoting uterine cellular aging.Conclusions This study identifies a novel regulatory pathway in which miR-210a-5p modulates uterine aging through the RASL11B-MAPK signaling cascade.The findings provide mechanistic insight into age-related reproductive decline in hens and suggest that targeting this pathway may offer new strategies for maintaining uterine function and extending reproductive lifespan in poultry.展开更多
Background Despite growing concerns about the adverse effects of antibiotics in farm animals,there has been little investigation of the effects of florfenicol in laying hens.This study examined the effect of florfenic...Background Despite growing concerns about the adverse effects of antibiotics in farm animals,there has been little investigation of the effects of florfenicol in laying hens.This study examined the effect of florfenicol on the intestinal homeostasis,immune system,and pathogen susceptibility of laying hens.Results The oral administration of florfenicol at field-relevant levels for 5 d resulted in a decrease in the gut microbiota genera Lactobacillus,Bacillus,and Bacteroides,indicating the development of intestinal dysbiosis.The dysbiosis led to decreased mRNA levels of key regulators peroxisome proliferator-activated receptor gamma(PPAR-γ)and hypoxia-inducible factor-1α(HIF-1α),compromising intestinal hypoxia.Intestinal homeostasis was also disrupted,with decreased expression of Occludin and Mucin 2(Muc2)genes combined with increased gut epithelial permeability.The breakdown in intestinal homeostasis and immune function provided a favorable environment for opportunistic bacteria like avian pathogenic Escherichia coli(APEC),culminating in systemic infection.Immunologically,florfenicol treatment resulted in increased proportion and absolute number of MRC1L-B^(+)monocytes/macrophages in the spleen,indicating an exacerbated infection.Furthermore,both the proportion and absolute number ofγδT cells in the lamina propria of the cecum decreased.Treatment with florfenicol reduced butyrate levels in the cecum.However,the administration of butyrate before and during florfenicol treatment restored factors associated with intestinal homeostasis,including PPAR-γ,Occludin,and Muc2,while partially restoring HIF-1α,normalized intestinal hypoxia and gut permeability,and reversed immune cell changes,suppressing APEC systemic infection.Conclusion The uncontrolled and widespread use of florfenicol can negatively affect intestinal health in chickens.Specifically,florfenicol was found to impair intestinal homeostasis and immune function in laying hens,including by reducing butyrate levels,thereby increasing their susceptibility to systemic APEC infection.The development of strategies for mitigating the adverse effects of florfenicol on gut health and pathogen susceptibility in laying hens is therefore essential.展开更多
Multi-material 3D sand printing has gained significant attention;however,research has mainly focused on materials and mechanisms,with limited exploration of optimizing the sand-laying process through numerical simulat...Multi-material 3D sand printing has gained significant attention;however,research has mainly focused on materials and mechanisms,with limited exploration of optimizing the sand-laying process through numerical simulations.In this study,we investigated the dynamic behavior of sand particles during a vibratory sand-laying process for multi-material additive manufacturing using discrete element simulations.The objective is to enable precise control over the amount and distribution of sand for multi-material printing.In this study,we combined experiments and simulations to calibrate the contact parameters of different sands and establish a relationship between the curing agent content and surface energy of sand particles.A model for the vibratory fall of multimaterial sand was developed to study the motion characteristics of sand particles.This allows for macro-control over the sand spreading flow and high-quality multi-material sand laying.The results show that the flow rate of falling sand increases with decreasing surface energy of the particles,wider spreader openings,and higher vibration frequencies.For silica and chromite sands,when their surface energy ranged from 0.15 to 25 J·m^(2)and0.01-0.03 J·m^(2),respectively,and the sand spreader opening was 6 mm with a vibration frequency of 500 Hz,the sand flow rates of both materials became nearly identical.However,a higher sand paving speed and height increased the scattering of sand particles outside the target area,thereby decreasing the paving quality.The results accomplished in this study enable precise and uniform sand particle deposition and offers guidelines for optimizing sand speed and height,thus expanding the application of multi-material sand 3D printing in complex and high-performance manufacturing.展开更多
Background:This study aimed to investigate whether the combination of Macleaya cordata extract(MCE)and Bacil-lus could improve the laying performance and health of laying hens better.Methods:A total of 36029-week-old ...Background:This study aimed to investigate whether the combination of Macleaya cordata extract(MCE)and Bacil-lus could improve the laying performance and health of laying hens better.Methods:A total of 36029-week-old Jingbai laying hens were randomly divided into 4 treatments:control group(basal diet),MCE group(basal diet+MCE),Probiotics Bacillus Compound(PBC)group(basal diet+compound Bacil-lus),MCE+PBC group(basal diet+MCE+compound Bacillus).The feeding experiment lasted for 42 d.Results:The results showed that the laying rate and the average daily egg mass in the MCE+PBC group were significantly higher than those in the control group(P<0.05)and better than the MCE and PBC group.Combina-tion of MCE and Bacillus significantly increased the content of follicle-stimulating hormone(FSH)in the serum and up-regulated the expression of related hormone receptor gene(estrogen receptor-β,FSHR and luteinizing hormone/choriogonadotropin receptor)in the ovary of laying hens(P<0.05).In the MCE+PBC group,the mRNA expressions of zonula occluden-1,Occludin and mucin-2 in jejunum was increased and the intestinal epithelial barrier detected by transmission electron microscopy was enhanced compared with the control group(P<0.05).In addition,compared with the control group,combination of MCE and Bacillus significantly increased the total antioxidant capacity and catalase activity(P<0.05),and down-regulated the mRNA expressions of inflammation-related genes(interleukin-1βand tumor necrosis factor-α)as well as apoptosis-related genes(Caspase 3,Caspase 8 and P53)(P<0.05).The concen-tration of acetic acid and butyric acid in the cecum content of laying hens in the MCE+PBC group was significantly increased compared with the control group(P<0.05).Conclusions:Collectively,dietary supplementation of 600μg/kg MCE and 5×108 CFU/kg compound Bacillus can improve laying performance by improving microbiota to enhance antioxidant capacity and intestinal barrier,regulate reproductive hormones and the concentration of cecal short-chain fatty acids of laying hens,and the combined effect of MCE and Bacillus is better than that of single supplementation.展开更多
Background:Soya saponin(SS),an active compound in soybean meals,has been widely studied in the medical field.However,it was considered as an anti-nutritional factor in poultry diets.The objective of this experiment wa...Background:Soya saponin(SS),an active compound in soybean meals,has been widely studied in the medical field.However,it was considered as an anti-nutritional factor in poultry diets.The objective of this experiment was to measure the effects of dietary SS using three dietary treatments on egg-laying performance and immune function of laying hens.Birds were fed a low soybean meal basal diet(CON),a low-SS diet(50 SS)containing 50mg/kg SS,or a high-SS diet(500 SS)containing 500 mg/kg SS for 10 weeks.At the end of the 5th and 10th week of the trial,samples were collected for analysis.Results:Results showed that with 50 mg/kg SS supplementation,the egg production rate,feed conversion ratio(FCR),and eggshell quality tended to be improved.Serum follicle stimulating hormone(FSH)and Interleukin-4(IL-4)levels were also elevated as well as the peripheral blood LPS stimulation index,the proportion of B lymphocytes,and antibody titer of bovine serum albumin(BSA).We also found that mRNA levels of follicle stimulating hormone receptor(FSHR)in ovarian,nuclear transcription factor kappa B(NF-κB),Transforming growth factor(TGF-β)and interferonγ(IFN-γ)in spleen were up-regulated at the end of the trial.Additionally,dietary 50 mg/kg SS improved the ileal flora via up-regulating the relative abundance of Lactobacillus,Romboutsia and Lactobacillus delbrueckii.Although the immune related indicators were improved with 500 mg/kg SS supplemented,it seemed to have a negative influence on the laying-performance.Specifically,serum alanine aminotransferase(ALT),alkaline phosphatase(ALP),and the ratio of IFN-γto IL-4 were increased in the 500 SS group at the end of the trial.The m RNA levels of gonadotropin releasing hormone 1(GnRH1)in Hypothalamus,the estrogen related receptor(ERR)in ovaries were downregulated as well as the egg production rate during the trial with 500 mg/kg SS supplemented.Conclusions:The egg production performance was improved by dietary supplemented with 50 mg/kg SS via increasing ovarian FSHR transcription level and serum estrogen level.A beneficial shift in intestinal microflora was recorded,and the immune function of laying hens was also improved with 50 mg/kg SS supplementation.Surprisingly,the long-term supplementation of 500 mg/kg SS exerted a negative impact on the laying performance and physiological functions of the liver of laying hens.展开更多
Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian la...Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian laying hens were investigated and the possibility of quercetin to decrease cholesterol in eggs and Low Density Lipoprotein cholesterol（LDL-cholesterol） in laying hens were explored. A total of 240 laying hens at 29-week-old were randomly assigned to four treatments, with six replicates of 10 birds per replicate. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g · kg-1 quercetin for 8 weeks. Layer performance, lipid concentration in livers, yolks and serum were measured at the end of the experiment. The results showed that laying rate had a quadratic correlation with the level of quercetin（p=0.056） and was maximized by the supplement level of 0.2 g · kg-1 diet. When the level of dietary quercetin increased, feed-egg ratio decreased. Crude fat and the total cholesterol of livers decreased by supplementation of quercetin. The total cholesterols of yolks also decreased and had a quadratic correlation with the levels of quercetin（p=0.019）. Insulin increased by supplement of quercetin. In conclusion, quercetin improved the performance and reduced egg yolk cholesterol by affecting serum hormone levels.展开更多
Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying...Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying birds that were randomly allotted to dietary treatments. The four experimental diets had five replicates each and three birds per repli-cate. Diet 1 contained 14% crude protein (CP), while diet 2 contained 15% CP, diets 3 and 4 contained 16% and 17% CP respectively. The experimental birds were fed for 10 weeks and the data collected were statistically analysed. Apparent variations recorded for all the performance characteristics such as Egg number, Hen-day production, Feed Conversion Ratio (FCR) and weight gain were significantly different (p < 0.05). The best FCR value were recorded by birds fed 17% CP (3.45), while the highest weight gain mean value were also recorded by birds fed 17% CP value. Findings indicated a direct relationship between dietary crude protein values and performance.展开更多
[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1&...[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.展开更多
[ Objective] To study the effects of yeast chromium combined with probiotics on laying performance, intestinal microflora and digestive enzyme activities of laying hens. [ Method] A total of 432 healthy 40-week-old Ro...[ Objective] To study the effects of yeast chromium combined with probiotics on laying performance, intestinal microflora and digestive enzyme activities of laying hens. [ Method] A total of 432 healthy 40-week-old Roman brown laying hens were randomly divided into nine groups. Laying hens in control group were fed with basal diet, laying hens in test groups were fed with basal diet combining with different levels of yeast chromium （0,400,600 μg/kg） or probiotics （0,400,800 mg/kg）. [ Result] Yeast chromium, probiotics or yeast chromium combined with probiotics adding into feeds could significantly increased the laying rate （ P 〈 0.05 ） and significantly reduced feed-egg rate （ P 〈 0.05 ）. Joint use of yeast chromium and probiotics had significant interaction effects on laying rate and feed conversion rate（P 〈 0. 05）. Adding of yeast chromium combined with probiotics in diets could significantly increased the amount of Lactobacillus and Bifidobacterium （P 〈0.05 ） in ileum and cecum of laying hens, and significantly reduced the amount of Escherichia coli and Salmonella （P 〈0.05 ） , in addition, the activity of total protease, lipase and amylase in duodenal contents were significantly increased （ P 〈 0.05 ）. Joint use of yeast chromium and probioties had sig- nificant interaction effects on the activity of total protease, lipase and amylase in laying hens duodenal contents （ P 〈 0.05 ）. [ Conclusion ] Joint adding of 600μg/kg yeast chromium and 800 mg/kg probiotics in diets in summer had best effects on laying performance, intestinal microflora and digestive enzyme activities of laying hens.展开更多
[ Objective] The paper presents the polymorphism of neuropeptide Y gene （NPY） and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenc...[ Objective] The paper presents the polymorphism of neuropeptide Y gene （NPY） and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenchang chicken. [Method] The polymorphism of NPYgene at Dra I site was detected by PCR-RFLP, and the genotypes and the genetic stability were determined. The correlation between the polymorphism and traits at first laying （age, body weight and egg weight） was also analyzed. [Result] There were three kinds of genotype of NPYgene at Dra I site in Wenchang chicken, designated as AA, AB and BB; the distribution of these genotypes was consistent with the Hardy -Weinberg law; age and egg weight were not significantly different among the three genotypes （ P 〉0.05）, and body weight was extremely significantly different （ P 〈0.01 ）. [ Conclusion] The NPYgene of Wenchang chicken is in Hardy -Weinberg equilibrium at Dra I site, and its genetic polymorphism affects body weight at first laying.展开更多
Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on w...Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on wire rod kinematics and dynamics analyses are not reported before. In order to design and manufacture the laying pipe, the motion and force process of the wire rod in the laying pipe should be studied. In this paper, a novel approach is proposed to investigate the force modeling for hot-rolled wire rod in laying pipe. An idea of limited element method is used to analysis and calculates the forces between laying pipe inner surface and wire rod. The design requirements of laying pipe curve for manufacturing are discussed. The kinematics and dynamics modeling for numerical calculation are built. A laying pipe curve equation is proposed by discussing design boundary conditions. Numerical results with di erent laying pipe curves design parameters are plotted and compared. The proposed approach performs good result which can be applied for laying pipe curve design and analysis for engineering application.展开更多
基金supported by National Key R&D Program of China(2023YFD1301200)China Agriculture Research Systems(CARS-40-K11)+2 种基金Beijing Agriculture Innovation Consortium(BAIC06-2024-G05)Strategic Priority Research Program of the National Center of Technology Innovation for Pigs(NCTIP-XD/C08)The Chinese Academy of Agricultural Science and Technology Innovation Project(ASTIP-IAS-12)。
文摘Background Caffeic acid(CA)and its derivative,chlorogenic acid(CGA),have shown promise in preventing and alleviating fatty liver disease.CA,compared to CGA,has much lower production costs and higher bioavailability,making it a potentially superior feed additive.However,the efficacy,mechanistic differences,and comparative impacts of CA and CGA on fatty liver disease in laying hens remain unclear.This study aimed to evaluate and compare the effects of CA and CGA on production performance,egg quality,and fatty liver disease in laying hens.Results A total of 1,44061-week-old Hyline Brown laying hens were randomly divided into 8 groups and fed diets supplemented with basal diet,25,50,100 and 200 mg/kg of CA,and 100,200 and 400 mg/kg of CGA(CON,CA25,CA50,CA100,CA200,CGA100,CGA200 and CGA400,respectively)for 12 weeks.Both CA and CGA improved production performance and egg quality,while reducing markers of hepatic damage and lipid accumulation.CA and CGA significantly decreased TG,TC,and LDL-C levels and increased T-SOD activity.Transcriptomic and proteomic analyses revealed that CA and CGA reduced hepatic lipid accumulation through downregulation of lipid biosynthesis-related genes(ACLY,ACACA,FASN,and SCD1)and enhanced lipid transport and oxidation genes(FABPs,CD36,CPT1A,ACOX1,and SCP2).Of note,low-dose CA25 exhibited equivalent efficacy to the higher dose CGA100 group in alleviating fatty liver conditions.Mechanistically,CA and CGA alleviated lipid accumulation via activation of the ADPN-AMPK-PPARαsignaling pathway.Conclusions This study demonstrates that dietary CA and CGA effectively improve laying performance,egg quality,and hepatic lipid metabolism in laying hens,with CA potentially being more economical and efficient.Transcriptomic and proteomic evidence highlight shared mechanisms between CA25 and CGA100.These findings provide a foundation for CA and CGA as therapeutic agents for fatty liver disease and related metabolic diseases in hens,and also offer insights into the targeted modification of CGA(including the isomer of CGA)into CA,thereby providing novel strategies for the efficient utilization of CGA.Highlights(1)Dietary CA and CGA improve fatty liver,laying performance and egg quality.(2)Lower dose of CA25 achieves the equivalent improvement as CGA100 or CGA200.(3)CA and CGA mediate the ADPN-AMPK-PPARαpathway to alleviate fatty liver.
基金supported by the China Agriculture Research System of MOF and MARA(CARS-42-4)School Cooperation Project of Ya’an(21SXHZ0028)the Key Technology Support Program of Sichuan Province,China(2021YFYZ0014),for the financial support。
文摘The low egg production of goose greatly limits the development of the industry.China possesses the most abundant goose breeds resources.In this study,genome resequencing data of swan goose(Anser cygnoides)and domesticated high and low laying goose breeds(Anser cygnoides domestiation)were used to identify key genes related to egg laying ability in geese and verify their functions.Selective sweep analyses revealed 416 genes that were specifically selected during the domestication process from swan geese to high laying geese.Furthermore,SNPs and Indels markers were used in GWAS analyses between high and low laying breed geese.The results showed that RTCB,BPIFC,SYN3,SYNE1,VIP,and ESR1 may be related to the differences in laying ability of geese.Notably,only ESR1 was identified simultaneously by GWAS and selective sweep analysis.The genotype of Indelchr3:54429172,located downstream of ESR1,was confirmed to affect the expression of ESR1 in the ovarian stroma and showed significant correlation with body weight at first egg and laying frequency of geese.CCK-8,EdU,and flow cytometry confirmed that ESR1 can promote the apoptosis of goose pre-hierarchical follicles ganulosa cells(phGCs)and inhibit their proliferation.Combined with transcriptome data,it was found ESR1 involved in the function of goose phGCs may be related to MAPK and TGF-beta signaling pathways.Overall,our study used genomic information from different goose breeds to identify an indel located in the downstream of ESR1 associated with goose laying ability.The main pathways and biological processes of ESR1 involved in the regulation of goose laying ability were identified by cell biology and transcriptomics methods.These results are helpful to further understand the laying ability characteristics of goose and improve the egg production of geese.
基金supported by the National Key Research and Development Program of China (Nos.2018YFA0901101,2018YFA0901103,and 2017YFC1600301)the National Natural Science Foundation of China (Nos.22076216,21976201,and 21836004).
文摘The evaluation of toxicity related to polychlorinated dibenzo-p-dioxins and furans(PCDD/Fs)and dioxin-like polychlorinated biphenyls(DL-PCBs)is crucial for a comprehensive risk assessment in real-world exposure scenarios.This study employed a controlled feeding experiment to investigate the metabolic effects of dioxin-like compounds(DLCs)on laying hens via feed exposure.Diets enriched with two concentrations(1.17 and 5.13 pg toxic equivalents(TEQ)/g dry weight(dw))were administered over 14 days,followed by 28 days of clean feed.Metabolomics analyses of blood samples revealed significant metabolic variations between PCDD/Fs and DL-PCBs exposed groups and controls,reflecting the induced metabolic disruption.Distinct changes were observed in sphingosine,palmitoleic acid,linoleate,linolenic acid,taurocholic acid,indole acrylic acid,and dibutyl phthalate levels,implying possible connections between PCDD/Fs and DL-PCBs toxic effects and energy-neuronal imbalances,along with lipid accumulation and anomalous amino acid metabolism,impacting taurine metabolism.Moreover,we identified three differential endogenous metabolites—L-tryptophan,indole-3-acetaldehyde,and indole acrylic acid—as potential ligands for the aryl hydrocarbon receptor(AhR),suggesting their role inmediating PCDD/Fs and DL-PCBs toxicity.This comprehensive investigation provides novel insights into the metabolic alterations induced by PCDD/Fs and DL-PCBs in laying hens,thereby enhancing our ability to assess risks associated with their exposure in human populations.
基金financially supported by the Collaborative Extension Program for Advancements in Agricultural Technologies of Zhejiang Province(Grant no:2023ZDXT15)the Key Research&Development Program of Zhejiang Province(Grant no:2024C02004)Bureau of Science and Technology of Xinchang County Foundation.
文摘Background Systemic inflammatory responses and oxidative stress occur in laying hens during the aging process,particularly during the post-peaking laying period,which generally result in multi-organ damages,leading to significant declines in egg performance and quality.Chlorogenic acid(CGA)-enriched extract from Eucommia ulmoides leaves has anti-inflammatory and antioxidant activities.However,the mechanisms underlying whether and how CGA alleviates systemic inflammatory responses and oxidative stress to improve egg performance and quality in postpeaking laying hens remain unclear.In this study,the potential regulatory mechanisms of CGA in alleviating inflammatory responses and oxidative stress along the gut-liver axis were investigated.A total of 36055-week-old Hy-line white-laying hens were randomly selected and divided into four groups.The hens in the four groups were fed a basal diet(CON)or basal diets supplemented with 200,400,and 800 mg/kg of CGA(CGA200,CGA400,and CGA800,respectively)for 10 weeks.Results The results demonstrated that CGA significantly alleviated intestinal and hepatic damages resulting from systemic inflammatory responses and oxidative stress,thereby improving the laying performance and egg quality of post-peaking laying hens.CGA reduced systemic inflammation by improving intestinal barrier function and modulating inflammation-associated microbiota(Blautia and Megamonas),thus inhibiting endotoxin translocation.CGA can also reduce oxidative stress by upregulating the NRF-2 pathway-related genes and increasing antioxidant enzyme activities in the liver.The results of transcriptome sequencing revealed that CGA promoted lipid metabolism by regulating hepatic adipocytokine pathway-related genes/protein and reduced the inflammatory responses and apoptosis in liver by regulating PI3K/AKT pathway-related genes/proteins,which was also verified by qPCR and western blotting.Conclusion CGA alleviated multi-organ damages and dysfunction by suppressing the systemic inflammatory responses and oxidative stress in post-peaking laying hens,thereby improving egg performance and quality.The optimal dose of CGA is 400 mg/kg in this experiment.These results provide a sound theoretical basis for the application of CGA as an exogenous animal feed additive for laying hens.
基金financially supported by the National Natural Science Foundation of China(32072774)the China Postdoctoral Science Foundation(2023M733822)+2 种基金the Beijing Innovation Consortium of Agriculture Research System(BAIC04),Chinathe earmarked fund for CARS National System for Layer Production Technology,China(CARS-40)the Agricultural Science and Technology Innovation Program(ASTIP)of the Chinese Academy of Agricultural Sciences。
文摘This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the effects.A total of 288 Hy-Line Brown layers were randomly assigned into 3 treatments and respectively offered soybean meal(SBM)-based diet,LCSM-based diet,and LCSM-based diet supplemented with 0.435%L-Ser.Dietary Ser supplementation reversed the decrease in quality indices of albumen,including the proportion of thick albumen(P<0.05),thick-to-thin ratio(P<0.05),albumen height(P<0.05),Haugh unit(P<0.05),and apparent viscosity that were caused by LCSM intake.Also,dietary Ser supplementation mitigated the LCSM-induced reduction in ovomucin content of the albumen(P<0.05).FT-IR analysis of ovomucin revealed differences in second derivative spectra at 1,200-800 cm^(-1) between birds received SBM-and LCSM-based diets,meanwhile,the α-helix of ovomucin was decreased by LCSM but increased by Ser addition(P<0.05).Furthermore,Ser addition up-regulated the mRNA expression of β-ovomucin in magnum mucosa at 2 and 7.5 h post-oviposition(P<0.05).Ser mitigated the LCSMinduced impairment of magnum epithelium,increased goblet cell counts(P<0.05),and up-regulated the expression of occludin,mucin 2,and the relevant glycosyltransferases for O-glycosylation in magnum mucosa(P<0.05).Conclusively,the alleviating effect of Ser on declining albumen quality due to dietary LCSM,could be explained by the efficacy of Ser in regulating ovomucin synthesis.This regulation occurred at the levels of transcription and posttranscriptional O-glycosylation modification ofβ-ovomucin,while positive effect on magnum morphology and barrier function could also in part account for the ovomucin content.This would provide a promising research direction on the adoption of nutritional interventions for manipulation of egg white quality from perspectives of albumen protein synthesis.
基金supported by the National Natural Science Foundation of China(32302774)Beijing Innovation Consortium of Agriculture Research System(BAIC04)+1 种基金China Agriculture Research System(CARS-40)the Agricultural Science and Technology Innovation Program of the Feed Research Institute of the Chinese Academy of Agricultural Sciences(CAASIFR-ZDRW202402).
文摘Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation and minimal toxicity.Selenium-enriched yeast(SeY)is a well-established source,while selenium-enriched lactobacilli(SeL),a newer alternative,offers the added benefits of probiotics.This study examined the effects of SeY and SeL on egg quality,antioxidant capacity,Se deposition,and gut health in laying hens.After a two-week pre-treatment with a Sedeficient diet(SeD),450 Hy-Line Brown laying hens(30-week-old)were assigned into five dietary groups with six replicates of 15 hens each.The groups included a SeD,SeD supplemented with 1.5 mg Se/kg from SeY(SeY15),or 1.5,3.0,and 6.0 mg Se/kg from SeL(SeL15,SeL30,SeL60).The feeding trial lasted for 12 weeks.Results SeY15 and SeL15 improved the feed-to-egg ratio(P<0.05)in the latter stages.Haugh units were significantly increased(P<0.05)in the SeY15 and SeL30 groups,while darker yolk color(P<0.05)was observed in the SeY15,SeL15,and SeL60 groups.All Se-supplemented diets increased Se content in whole eggs,albumen,and yolk(P<0.05),while SeL groups showed a dose-dependent effect.Antioxidant enzyme activities increased,and MDA content decreased in the serum(P<0.05),with SeY15 showing the highest GSH-Px levels(P<0.05).SeL60 increased serum alkaline phosphatase and aspartate transaminase,and distorted the liver architecture(P<0.05).Se-diets reduced concentrations of reactive oxygen species(ROS)in the ileum and liver(P<0.05).SeL15 improved the ileal villus height-tocrypt depth ratio(P<0.05).SeY15 and/or SeL15 up-regulated TXNRD1 and SEPHS1 mRNA while down-regulating SCLY expression in the liver.SeY15 altered ileal microbiota by increasing both beneficial and pathogenic bacteria,whereas SeL15 predominantly boosted beneficial bacteria.Conclusion SeL integrates the antioxidant properties of organic Se with the probiotic benefits on gut health,resulting in a performance-enhancing effect comparable to that of SeY.However,high SeL level(6.0 mg Se/kg)compromised productivity and metabolic functions while enhancing Se deposition.
基金funded by the National Key Research and Development Program of China,grant number 2021YFD1300600Sichuan Science and Technology Program(2024YFNH0025,2022YFYZ0005,2021YFYZ0031)China Agriculture Research System of MOF and MARA(CARS-40).
文摘Background Uterine aging is a key factor contributing to the deterioration of egg quality and reproductive performance in laying hens.Despite its importance,the molecular mechanisms underlying uterine aging remain poorly defined.This study aimed to characterize gene expression and regulatory changes associated with uterine aging in hens at different life stages.Results Transcriptomic Analysis of uterine tissue from hens aged 350,500,And 700 d revealed dynamic changes in gene expression patterns during aging.A significant upregulation of genes involved in cellular senescence was observed,including increased expression of the p53 signaling pathway And markers associated with inflammation And cell cycle arrest.The most notable changes occurred between 350 And 500 d of age,suggesting this as a critical window for the onset of uterine aging.MicroRNA sequencing identified miR-210a-5p as significantly reduced with age.Target prediction and experimental validation showed that miR-210a-5p directly suppresses the expression of RASL11B,a Ras-like small GTPase that activates the MAPK signaling pathway.In primary uterine epithelial cells,reduced miR-210a-5p levels led to elevated RASL11B expression,increased activation of B-Raf,MEK,and ERK proteins,and enhanced expression of aging-related genes and inflammatory factors.In contrast,overexpression of miR-210a-5p or inhibition of the MAPK pathway delayed senescence and reduced inflammatory signaling.RASL11B overexpression was sufficient to induce aging phenotypes,confirming its central role in promoting uterine cellular aging.Conclusions This study identifies a novel regulatory pathway in which miR-210a-5p modulates uterine aging through the RASL11B-MAPK signaling cascade.The findings provide mechanistic insight into age-related reproductive decline in hens and suggest that targeting this pathway may offer new strategies for maintaining uterine function and extending reproductive lifespan in poultry.
基金supported by a the National Research Foundation(NRF),funded by the Ministry of Science and ICT(RS-2023-00218476,RS-2024-00454619)the Cooperative Research Program for Agriculture Science and Technology Development(RS-2022-RD010165)+1 种基金the Ministry of Health&Welfare,Republic of Korea(RS-2022-KH128577)the BK21 FOUR Program of the Department of Agricultural Biotechnology,Seoul National University,Seoul,Korea.
文摘Background Despite growing concerns about the adverse effects of antibiotics in farm animals,there has been little investigation of the effects of florfenicol in laying hens.This study examined the effect of florfenicol on the intestinal homeostasis,immune system,and pathogen susceptibility of laying hens.Results The oral administration of florfenicol at field-relevant levels for 5 d resulted in a decrease in the gut microbiota genera Lactobacillus,Bacillus,and Bacteroides,indicating the development of intestinal dysbiosis.The dysbiosis led to decreased mRNA levels of key regulators peroxisome proliferator-activated receptor gamma(PPAR-γ)and hypoxia-inducible factor-1α(HIF-1α),compromising intestinal hypoxia.Intestinal homeostasis was also disrupted,with decreased expression of Occludin and Mucin 2(Muc2)genes combined with increased gut epithelial permeability.The breakdown in intestinal homeostasis and immune function provided a favorable environment for opportunistic bacteria like avian pathogenic Escherichia coli(APEC),culminating in systemic infection.Immunologically,florfenicol treatment resulted in increased proportion and absolute number of MRC1L-B^(+)monocytes/macrophages in the spleen,indicating an exacerbated infection.Furthermore,both the proportion and absolute number ofγδT cells in the lamina propria of the cecum decreased.Treatment with florfenicol reduced butyrate levels in the cecum.However,the administration of butyrate before and during florfenicol treatment restored factors associated with intestinal homeostasis,including PPAR-γ,Occludin,and Muc2,while partially restoring HIF-1α,normalized intestinal hypoxia and gut permeability,and reversed immune cell changes,suppressing APEC systemic infection.Conclusion The uncontrolled and widespread use of florfenicol can negatively affect intestinal health in chickens.Specifically,florfenicol was found to impair intestinal homeostasis and immune function in laying hens,including by reducing butyrate levels,thereby increasing their susceptibility to systemic APEC infection.The development of strategies for mitigating the adverse effects of florfenicol on gut health and pathogen susceptibility in laying hens is therefore essential.
基金supported by the Jiangsu Provincial Basic Research Program(Natural Science Foundation)Youth Fund(Grant No.BK20230885)the International Joint Laboratory of Sustainable Manufacturing,Ministry of Education and Fundamental Research Funds for Central Universities(Grant No.NG2024012)Major Project on Fundamental Research of Aero-Engines and Gas Turbines,Ministry of Industry and Information Technology Special Project on High-Quality Development(Grant No.J2022-Ⅶ-0006-0048)。
文摘Multi-material 3D sand printing has gained significant attention;however,research has mainly focused on materials and mechanisms,with limited exploration of optimizing the sand-laying process through numerical simulations.In this study,we investigated the dynamic behavior of sand particles during a vibratory sand-laying process for multi-material additive manufacturing using discrete element simulations.The objective is to enable precise control over the amount and distribution of sand for multi-material printing.In this study,we combined experiments and simulations to calibrate the contact parameters of different sands and establish a relationship between the curing agent content and surface energy of sand particles.A model for the vibratory fall of multimaterial sand was developed to study the motion characteristics of sand particles.This allows for macro-control over the sand spreading flow and high-quality multi-material sand laying.The results show that the flow rate of falling sand increases with decreasing surface energy of the particles,wider spreader openings,and higher vibration frequencies.For silica and chromite sands,when their surface energy ranged from 0.15 to 25 J·m^(2)and0.01-0.03 J·m^(2),respectively,and the sand spreader opening was 6 mm with a vibration frequency of 500 Hz,the sand flow rates of both materials became nearly identical.However,a higher sand paving speed and height increased the scattering of sand particles outside the target area,thereby decreasing the paving quality.The results accomplished in this study enable precise and uniform sand particle deposition and offers guidelines for optimizing sand speed and height,thus expanding the application of multi-material sand 3D printing in complex and high-performance manufacturing.
基金supported by the National Natural Science Foundation of China(No.32072766,31672460,31472128)Natural Science Foundation of Zhejiang province(No.LZ20C170002)the National High-Tech R&D Program Project(863)of China(NO.2013AA102803D).
文摘Background:This study aimed to investigate whether the combination of Macleaya cordata extract(MCE)and Bacil-lus could improve the laying performance and health of laying hens better.Methods:A total of 36029-week-old Jingbai laying hens were randomly divided into 4 treatments:control group(basal diet),MCE group(basal diet+MCE),Probiotics Bacillus Compound(PBC)group(basal diet+compound Bacil-lus),MCE+PBC group(basal diet+MCE+compound Bacillus).The feeding experiment lasted for 42 d.Results:The results showed that the laying rate and the average daily egg mass in the MCE+PBC group were significantly higher than those in the control group(P<0.05)and better than the MCE and PBC group.Combina-tion of MCE and Bacillus significantly increased the content of follicle-stimulating hormone(FSH)in the serum and up-regulated the expression of related hormone receptor gene(estrogen receptor-β,FSHR and luteinizing hormone/choriogonadotropin receptor)in the ovary of laying hens(P<0.05).In the MCE+PBC group,the mRNA expressions of zonula occluden-1,Occludin and mucin-2 in jejunum was increased and the intestinal epithelial barrier detected by transmission electron microscopy was enhanced compared with the control group(P<0.05).In addition,compared with the control group,combination of MCE and Bacillus significantly increased the total antioxidant capacity and catalase activity(P<0.05),and down-regulated the mRNA expressions of inflammation-related genes(interleukin-1βand tumor necrosis factor-α)as well as apoptosis-related genes(Caspase 3,Caspase 8 and P53)(P<0.05).The concen-tration of acetic acid and butyric acid in the cecum content of laying hens in the MCE+PBC group was significantly increased compared with the control group(P<0.05).Conclusions:Collectively,dietary supplementation of 600μg/kg MCE and 5×108 CFU/kg compound Bacillus can improve laying performance by improving microbiota to enhance antioxidant capacity and intestinal barrier,regulate reproductive hormones and the concentration of cecal short-chain fatty acids of laying hens,and the combined effect of MCE and Bacillus is better than that of single supplementation.
基金funded by the China Agriculture Research System program(CARS-41-G11)。
文摘Background:Soya saponin(SS),an active compound in soybean meals,has been widely studied in the medical field.However,it was considered as an anti-nutritional factor in poultry diets.The objective of this experiment was to measure the effects of dietary SS using three dietary treatments on egg-laying performance and immune function of laying hens.Birds were fed a low soybean meal basal diet(CON),a low-SS diet(50 SS)containing 50mg/kg SS,or a high-SS diet(500 SS)containing 500 mg/kg SS for 10 weeks.At the end of the 5th and 10th week of the trial,samples were collected for analysis.Results:Results showed that with 50 mg/kg SS supplementation,the egg production rate,feed conversion ratio(FCR),and eggshell quality tended to be improved.Serum follicle stimulating hormone(FSH)and Interleukin-4(IL-4)levels were also elevated as well as the peripheral blood LPS stimulation index,the proportion of B lymphocytes,and antibody titer of bovine serum albumin(BSA).We also found that mRNA levels of follicle stimulating hormone receptor(FSHR)in ovarian,nuclear transcription factor kappa B(NF-κB),Transforming growth factor(TGF-β)and interferonγ(IFN-γ)in spleen were up-regulated at the end of the trial.Additionally,dietary 50 mg/kg SS improved the ileal flora via up-regulating the relative abundance of Lactobacillus,Romboutsia and Lactobacillus delbrueckii.Although the immune related indicators were improved with 500 mg/kg SS supplemented,it seemed to have a negative influence on the laying-performance.Specifically,serum alanine aminotransferase(ALT),alkaline phosphatase(ALP),and the ratio of IFN-γto IL-4 were increased in the 500 SS group at the end of the trial.The m RNA levels of gonadotropin releasing hormone 1(GnRH1)in Hypothalamus,the estrogen related receptor(ERR)in ovaries were downregulated as well as the egg production rate during the trial with 500 mg/kg SS supplemented.Conclusions:The egg production performance was improved by dietary supplemented with 50 mg/kg SS via increasing ovarian FSHR transcription level and serum estrogen level.A beneficial shift in intestinal microflora was recorded,and the immune function of laying hens was also improved with 50 mg/kg SS supplementation.Surprisingly,the long-term supplementation of 500 mg/kg SS exerted a negative impact on the laying performance and physiological functions of the liver of laying hens.
基金Supported by Heilongjiang Provincial Government(C2016017)Harbin Science and Technology Bureau(2015RQXXJ014)
文摘Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian laying hens were investigated and the possibility of quercetin to decrease cholesterol in eggs and Low Density Lipoprotein cholesterol（LDL-cholesterol） in laying hens were explored. A total of 240 laying hens at 29-week-old were randomly assigned to four treatments, with six replicates of 10 birds per replicate. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g · kg-1 quercetin for 8 weeks. Layer performance, lipid concentration in livers, yolks and serum were measured at the end of the experiment. The results showed that laying rate had a quadratic correlation with the level of quercetin（p=0.056） and was maximized by the supplement level of 0.2 g · kg-1 diet. When the level of dietary quercetin increased, feed-egg ratio decreased. Crude fat and the total cholesterol of livers decreased by supplementation of quercetin. The total cholesterols of yolks also decreased and had a quadratic correlation with the levels of quercetin（p=0.019）. Insulin increased by supplement of quercetin. In conclusion, quercetin improved the performance and reduced egg yolk cholesterol by affecting serum hormone levels.
文摘Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying birds that were randomly allotted to dietary treatments. The four experimental diets had five replicates each and three birds per repli-cate. Diet 1 contained 14% crude protein (CP), while diet 2 contained 15% CP, diets 3 and 4 contained 16% and 17% CP respectively. The experimental birds were fed for 10 weeks and the data collected were statistically analysed. Apparent variations recorded for all the performance characteristics such as Egg number, Hen-day production, Feed Conversion Ratio (FCR) and weight gain were significantly different (p < 0.05). The best FCR value were recorded by birds fed 17% CP (3.45), while the highest weight gain mean value were also recorded by birds fed 17% CP value. Findings indicated a direct relationship between dietary crude protein values and performance.
文摘[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.
基金Supported by Beijing Agricultural Vocational College Project(XY-BS-12-03)Beijing Agricultural Science and Technology Project(20120108)Beijing Agricultural Vocational College Technology R&D and Demonstration Fund(XY-YF-13-18)
文摘[ Objective] To study the effects of yeast chromium combined with probiotics on laying performance, intestinal microflora and digestive enzyme activities of laying hens. [ Method] A total of 432 healthy 40-week-old Roman brown laying hens were randomly divided into nine groups. Laying hens in control group were fed with basal diet, laying hens in test groups were fed with basal diet combining with different levels of yeast chromium （0,400,600 μg/kg） or probiotics （0,400,800 mg/kg）. [ Result] Yeast chromium, probiotics or yeast chromium combined with probiotics adding into feeds could significantly increased the laying rate （ P 〈 0.05 ） and significantly reduced feed-egg rate （ P 〈 0.05 ）. Joint use of yeast chromium and probiotics had significant interaction effects on laying rate and feed conversion rate（P 〈 0. 05）. Adding of yeast chromium combined with probiotics in diets could significantly increased the amount of Lactobacillus and Bifidobacterium （P 〈0.05 ） in ileum and cecum of laying hens, and significantly reduced the amount of Escherichia coli and Salmonella （P 〈0.05 ） , in addition, the activity of total protease, lipase and amylase in duodenal contents were significantly increased （ P 〈 0.05 ）. Joint use of yeast chromium and probioties had sig- nificant interaction effects on the activity of total protease, lipase and amylase in laying hens duodenal contents （ P 〈 0.05 ）. [ Conclusion ] Joint adding of 600μg/kg yeast chromium and 800 mg/kg probiotics in diets in summer had best effects on laying performance, intestinal microflora and digestive enzyme activities of laying hens.
文摘[ Objective] The paper presents the polymorphism of neuropeptide Y gene （NPY） and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenchang chicken. [Method] The polymorphism of NPYgene at Dra I site was detected by PCR-RFLP, and the genotypes and the genetic stability were determined. The correlation between the polymorphism and traits at first laying （age, body weight and egg weight） was also analyzed. [Result] There were three kinds of genotype of NPYgene at Dra I site in Wenchang chicken, designated as AA, AB and BB; the distribution of these genotypes was consistent with the Hardy -Weinberg law; age and egg weight were not significantly different among the three genotypes （ P 〉0.05）, and body weight was extremely significantly different （ P 〈0.01 ）. [ Conclusion] The NPYgene of Wenchang chicken is in Hardy -Weinberg equilibrium at Dra I site, and its genetic polymorphism affects body weight at first laying.
基金China Postdoctoral Science Foundation Project(Grant No.2017M611184)
文摘Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on wire rod kinematics and dynamics analyses are not reported before. In order to design and manufacture the laying pipe, the motion and force process of the wire rod in the laying pipe should be studied. In this paper, a novel approach is proposed to investigate the force modeling for hot-rolled wire rod in laying pipe. An idea of limited element method is used to analysis and calculates the forces between laying pipe inner surface and wire rod. The design requirements of laying pipe curve for manufacturing are discussed. The kinematics and dynamics modeling for numerical calculation are built. A laying pipe curve equation is proposed by discussing design boundary conditions. Numerical results with di erent laying pipe curves design parameters are plotted and compared. The proposed approach performs good result which can be applied for laying pipe curve design and analysis for engineering application.
