Background A deterioration in the meat quality of broilers has attracted much more attention in recent years.L-malic acid(MA)is evidenced to decrease meat drip loss in broilers,but the underlying molecular mechanisms ...Background A deterioration in the meat quality of broilers has attracted much more attention in recent years.L-malic acid(MA)is evidenced to decrease meat drip loss in broilers,but the underlying molecular mechanisms are still unclear.It’s also not sure whether the outputs obtained under experimental conditions can be obtained in a com-mercial condition.Here,we investigated the effects and mechanisms of dietary MA supplementation on chicken meat drip loss at large-scale rearing.Results Results showed that the growth performance and drip loss were improved by MA supplementation.Meat metabolome revealed that L-2-aminoadipic acid,β-aminoisobutyric acid,eicosapentaenoic acid,and nicotinamide,as well as amino acid metabolism pathways connected to the improvements of meat quality by MA addition.The transcriptome analysis further indicated that the effect of MA on drip loss was also related to the proper immune response,evidenced by the enhanced B cell receptor signaling pathway,NF-κB signaling pathway,TNF signaling pathway,and IL-17 signaling pathway.Conclusions We provided evidence that MA decreased chicken meat drip loss under commercial conditions.Metabolome and transcriptome revealed a comprehensive understanding of the underlying mechanisms.Together,MA could be used as a promising dietary supplement for enhancing the water-holding capacity of chicken meat.展开更多
Coriander(Coriandrum sativum L.)is recognized for its antioxidant property,as a kind of natural phenolic-rich ingredient.Polycyclic aromatic hydrocarbons(PAHs)present a class of heat-driven hazards in foods,especially...Coriander(Coriandrum sativum L.)is recognized for its antioxidant property,as a kind of natural phenolic-rich ingredient.Polycyclic aromatic hydrocarbons(PAHs)present a class of heat-driven hazards in foods,especially the processed meat.In this study,the effect of coriander root and leaf extract on the formation and inhibition of PAH8 in roasted duck wings was firstly investigated.Coriander root extract(CRE)and coriander leaf extract(CLE)with five concentration groups(200,400,600,800,1000 mg/L)were prepared respectively to marinate the duck wings.CRE marinade exhibited greater inhibitory effect on PAH8 formation in roasted duck wings that ranged from 65.0%-87.4%.The electron spin resonance study indicated a significantly positive correlation between PAH8 and free radical level,suggesting the participation of radicals in PAHs formation.Also,it was speculated that the inhibitory effect on PAH8 was related to the phenolic compounds identified in coriander marinades.CRE made greater inhibitory effect on the formation of PAH8 and could be considered as a kind of natural source to mitigate PAHs in heat-processed meat products.展开更多
Senecavirus A(SVA)has a positive-sense,single-stranded RNA genome.Its 5´untranslated region harbors an internal ribosome entry site(IRES),comprising 10 larger or smaller stem-loop structures(including a pseudokno...Senecavirus A(SVA)has a positive-sense,single-stranded RNA genome.Its 5´untranslated region harbors an internal ribosome entry site(IRES),comprising 10 larger or smaller stem-loop structures(including a pseudoknot)that have been demonstrated to be well conserved.However,it is still unclear whether each stem-loop subdomain,such as a single stem or loop,is also highly conserved.To clarify this issue in the present study,a set of 29 SVA cDNA clones were constructed by site-directed mutagenesis(SDM)on the IRES.The SDM-modified scenarios included:(1)stem-formed complementary sequences exchanging with each other;(2)loop transversion;(3)loop transition;and(4)point mutations.All cDNA clones were separately transfected into cells for rescuing viable viruses,whereas only four SVAs of interest could be recovered,and were genetically stable during 20 passages.One progeny grew significantly slower than the other three did.The dual-luciferase reporter assay showed that none of the SDM-modified IRESes significantly inhibited the IRES activity.Our previous study indicated that a single motif from any of the ten stem structures,if completely mutated,would cause the failure of virus recovery.Interestingly,our present study revealed three stem structures,whose individual complementary sequences could exchange with each other to rescue sequence-modifying SVAs.Moreover,one apical loop was demonstrated to have the ability to tolerate its own full-length transition,also having no impact on the recovery of sequence-modifying SVA.The present study suggested that not every stem-loop structure was strictly conserved in its conformation,while the full-length IRES itself was well conserved.This provides a new research direction on interaction between the IRES and many factors.展开更多
Background Carcass traits are crucial for broiler ducks,but carcass traits can only be measured postmortem.Genomic selection(GS)is an effective approach in animal breeding to improve selection and reduce costs.However...Background Carcass traits are crucial for broiler ducks,but carcass traits can only be measured postmortem.Genomic selection(GS)is an effective approach in animal breeding to improve selection and reduce costs.However,the performance of genomic prediction in duck carcass traits remains largely unknown.Results In this study,we estimated the genetic parameters,performed GS using different models and marker densi-ties,and compared the estimation performance between GS and conventional BLUP on 35 carcass traits in an F2 population of ducks.Most of the cut weight traits and intestine length traits were estimated to be high and moder-ate heritabilities,respectively,while the heritabilities of percentage slaughter traits were dynamic.The reliability of genome prediction using GBLUP increased by an average of 0.06 compared to the conventional BLUP method.The Permutation studies revealed that 50K markers had achieved ideal prediction reliability,while 3K markers still achieved 90.7%predictive capability would further reduce the cost for duck carcass traits.The genomic relationship matrix nor-malized by our true variance method instead of the widely used 2pi(1-pi)could achieve an increase in prediction reliability in most traits.We detected most of the bayesian models had a better performance,especially for BayesN.Compared to GBLUP,BayesN can further improve the predictive reliability with an average of 0.06 for duck carcass traits.Conclusion This study demonstrates genomic selection for duck carcass traits is promising.The genomic prediction can be further improved by modifying the genomic relationship matrix using our proposed true variance method and several Bayesian models.Permutation study provides a theoretical basis for the fact that low-density arrays can be used to reduce genotype costs in duck genome selection.展开更多
Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed t...Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed to investigate the impact of dietary supplementation of extra-Ile on lipogenesis,fatty acid profile and lipid accumulation in skeletal muscle in finishing pigs.Methods: Forty-eight barrows with initial body weight of 77.0 ± 0.1 kg were allotted to one of two groups and fed diets containing 0.39%,0.53% standardized ileal digestible(SID) Ile with six replicates per treatment and four pigs per replicate for 30 d.Results: Dietary Ile intake significantly improved the intramuscular fat(IMF) content and monounsaturated fatty acid(MUFA) concentration in the skeletal muscle(P < 0.05),and decreased the drip loss and shear force(P < 0.05) without influencing the growth performance of pigs(P > 0.05).Moreover,the phosphorylation of adenosine monophosphate activated protein kinase α(AMPKα) and acetyl coenzyme A carboxylase(ACC) proteins that monitor lipid metabolism were decreased in skeletal muscle of pigs offered extra-Ile diet(P < 0.05).The mRNA expression of adipose-specific genes adipocyte determination and differentiation factor 1(ADD1),fatty acid synthase(FAS),and stearoyl-CoA desaturase(SCD) were upregulated and the activity of SCD was increased as well(P < 0.05).Conclusions: Surplus dietary Ile intake could increase IMF accumulation and MUFA synthesis in skeletal muscle through depressing the phosphorylation of AMPKα-ACC and stimulating the expression and activity of SCD,and increasing the capability of lipogenesis in skeletal muscle.展开更多
Fasting is typically used before feeding metabolizable energy assessment in broilers.Previous studies have shown that fasting cause atrophy of the intestinal villus.Whether fasting affects intestinal permeability duri...Fasting is typically used before feeding metabolizable energy assessment in broilers.Previous studies have shown that fasting cause atrophy of the intestinal villus.Whether fasting affects intestinal permeability during refeeding by altering barrier function and nutrient absorption is of concern.Here,23-d-old broilers were randomly assigned to 5 treatments,fasted for 0,12,24,36,and 48 h,respectively,and then refed for 2 d,to study the impact of different duration of fasting on the intestinal regeneration and barrier function during refeeding.Results showed that the intestinal morphology in fasted birds was recovered in 2 d of refeeding at most.As fasting durations increased,enterocytes per intestinal villus were linearly and quadratically increased(both P<0.05),whereas goblet cells per intestinal villus was linearly decreased(both P<0.05).Besides,the mRNA level of lysozyme was linearly decreased as fasting durations increased during refeeding(both P<0.05),while quadratically increased mucin 2 was observed only after 1 d of refeeding(P<0.05).Linear increase effects were observed for claudin 2 and zonula occludens-1with increased fasting durations after 1 d of refeeding(all P<0.05),and linear and quadratical effects were observed for claudin 2 at 2 d of refeeding(both P<0.05).Besides,we found that intestinal permeability to creatinine,4 and 70 kD dextran were linearly and quadratically decreased with increased fasting durations at 6 h and 1 d of refeeding(all P<0.05).Furthermore,jejunum proteomic from birds refed for 6 h showed that birds fasted for 36 h showed increased antimicrobial peptides and upregulated retinol metabolism when compared to the nonfasted birds(P<0.05).Further study showed that retinyl ester catabolism was inhibited during fasting and enhanced during refeeding.Results of intestinal organoid culture showed that retinol benefits the cell proliferation and enterocyte differentiation.In conclusion,the intestinal permeability to small and large molecules was decreased during refeeding by strengthening the intestinal barrier function,and the activated retinol metabolism during refeeding is involved in the intestinal regeneration and strengthens the intestinal barrier.展开更多
Fluidic Catalytic Cracking(FCC)is a complex petrochemical process affected by many highly non-linear and interrelated factors.Product yield analysis,flue gas desulfurization prediction,and abnormal condition warning a...Fluidic Catalytic Cracking(FCC)is a complex petrochemical process affected by many highly non-linear and interrelated factors.Product yield analysis,flue gas desulfurization prediction,and abnormal condition warning are several key research directions in FCC.This paper will sort out the relevant research results of the existing Artificial Intelligence(AI)algorithms applied to the analysis and optimization of catalytic cracking processes,with a view to providing help for the follow-up research.Compared with the traditional mathematical mechanism method,the AI method can effectively solve the difficulties in FCC process modeling,such as high-dimensional,nonlinear,strong correlation,and large delay.AI methods applied in product yield analysis build models based on massive data.By fitting the functional relationship between operating variables and products,the excessive simplification of mechanism model can be avoided,resulting in high model accuracy.AI methods applied in flue gas desulfurization can be usually divided into two stages:modeling and optimization.In the modeling stage,data-driven methods are often used to build the system model or rule base;In the optimization stage,heuristic search or reinforcement learning methods can be applied to find the optimal operating parameters based on the constructed model or rule base.AI methods,including data-driven and knowledge-driven algorithms,are widely used in the abnormal condition warning.Knowledge-driven methods have advantages in interpretability and generalization,but disadvantages in construction difficulty and prediction recall.While the data-driven methods are just the opposite.Thus,some studies combine these two methods to obtain better results.展开更多
Porcine epidemic diarrhea(PED)caused by porcine epidemic diarrhea virus(PEDV)is one of the most devastating diseases in the global pig industry due to its high mortality rate in piglets.Maternal vaccines can effective...Porcine epidemic diarrhea(PED)caused by porcine epidemic diarrhea virus(PEDV)is one of the most devastating diseases in the global pig industry due to its high mortality rate in piglets.Maternal vaccines can effectively enhance the gut-mammary gland-secretory IgA axis to boost lactogenic immunity and passive protection of nursing piglets against PEDV challenge.From 2017 to 2021,we collected 882 diarrhea samples from 303 farms in China to investigate the epidemiology of PEDV.The result showed that about 52.15%(158/303)of the farms were positive for PEDV with an overall detection rate of 63.95%(564/882)of the samples.The S1 fragments of S gene from 104 strains were sequenced for the phylogenetic analysis.A total of 71 PEDV strains(68.27%)sequenced in this study were clustered into the predominant G2c subgroup,while the newly-defined G2d strains(9.62%)were identified in three provinces of China.The NH-TA2020 strain of G2c subgroup was isolated and cultured,and its infection to piglets caused watery diarrhea within 24 h,indicating its strong pathogenicity.Oral administration of NH-TA2020 strain to pregnant gilts stimulated high levels of IgA antibody in colostrum.The piglets fed by the gilts above were challenged with NH-TA2020 strain or CH-HeB-RY-2020 strain from G2d subgroup,and the clinical symptoms and virus shedding were significantly reduced compared to the mock group.Our findings suggest that G2c subgroup is the predominant branch circulating in China from 2017 to 2021.Oral administration of NH-TA2020 enhances maternal IgA and lactogenic immune responses,which confer protection against the homologous and emerging G2d PEDV strains challenges in neonates.展开更多
Certain hormones play important roles in modulating mammalian reproductive behaviour.Daidzein is a well-known isoflavonic phytoestrogen that possesses oestrogenic activity.This study was conducted to probe the effects...Certain hormones play important roles in modulating mammalian reproductive behaviour.Daidzein is a well-known isoflavonic phytoestrogen that possesses oestrogenic activity.This study was conducted to probe the effects of daidzein supplementation in gestation diets on the reproductive performance in sows.A total of 120 multiparous sows(Landrace x Yorkshire)were randomly assigned to 2 groups(n=60)and fed either a base diet(control)or one containing 200 mg/kg daidzein during gestation.We discovered that daidzein supplementation significantly increased the total number of piglets born per litter and number of piglets born alive per litter(P<0.05),decreased the farrowing time(P<0.05)and increased the serum oestrogen and progesterone concentrations(P<0.05)at 35 d of gestation.Moreover,serum immunoglobulin G(IgG)concentration and superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)activities were higher in the daidzein-treated group than in the control group at35 d of gestation(P<0.05).Daidzein increased the serum SOD activity and total anti-oxidative capacity(T-AOC)at 85 d of gestation(P<0.05).Interestingly,daidzein elevated the expression levels of the sodium-coupled neutral amino acid transporter 1(SLC38 A1)and insulin-like growth factor 1(IGF-1)genes in the placenta(P<0.05).These results suggest that daidzein ingestion could improve sow reproductive performance by changing serum hormones,elevating anti-oxidative capacity and upregulating critical functional genes in the placenta.展开更多
This study was conducted to evaluate the effects of feed form(mash and crumble-pellet) and feed particle size(fine, medium and coarse) on growth performance, carcass characteristics and digestive tract development of ...This study was conducted to evaluate the effects of feed form(mash and crumble-pellet) and feed particle size(fine, medium and coarse) on growth performance, carcass characteristics and digestive tract development of broilers. A total of 1,152 one day-old Ross 308 mixed-sex broilers were used in a factorial arrangement(2×3) based on a completely randomized design with six replicates of 32 birds each.Higher average daily gain(ADG) and average daily feed intake(ADFI) were observed(P < 0.01) for birds fed the crumble-pellet diets(CPD) than for those fed the mash diets(MD) during starter, grower and the entire experiment period. From d 1 to 40, birds fed CPD had a higher(P < 0.01) body weight(BW) than those fed MD. Birds fed CPD had a lower(P < 0.01) feed:gain ratio(F:G) during the starter phase than those fed MD. Medium or coarse particle size increased(P < 0.01) ADG and ADFI during the starter phase, but birds fed fine particle size diets had lower(P < 0.01) F:G during the grower phase. In MD,medium and coarse particle sizes resulted in higher(P < 0.05) BW, ADG and ADFI than fine particle size during the whole experiment. In CPD, particle size had no significant effect on growth performance, as indicated by a feed form × particle size interaction(P < 0.05). At 41 days of age, ten birds per treatment were randomly selected and killed for slaughter yields and digestive tract characteristics determination.It was shown that particle size and feed form alone had no significant effect on slaughter yields, so changes was the feed form × particle size interaction. The relative empty weight of the gizzard was greater(P < 0.01) and the relative length of the ileum was longer(P < 0.05) in birds fed MD than in those fed CPD. Overall, CPD improved growth performance during the entire period of the study with effects being less evident during the finisher phase than during the starter and grower phases, and the effect of feed particle size varied depending on feed form.展开更多
Methionine and its hydroxy analogue(MHA)have been shown to benefit mouse intestinal regeneration.The intestinal organoid is a good model that directly reflects the impact of certain nutrients or chemicals on intestina...Methionine and its hydroxy analogue(MHA)have been shown to benefit mouse intestinal regeneration.The intestinal organoid is a good model that directly reflects the impact of certain nutrients or chemicals on intestinal development.Here,we aimed to establish a chicken intestinal organoid culture method first and then use the model to explore the influence of methionine deficiency and MHA on intestinal organoid development.The results showed that 125-mm cell strainer exhibited the highest efficiency for chicken embryo crypt harvesting.We found that transforming growth factor-b inhibitor(A8301)supplementation promoted enterocyte differentiation at the expense of the proliferation of intestinal stem cells(ISC).The mitogen-activated protein kinase p38 inhibitor(SB202190)promoted intestinal organoid formation and enterocyte differentiation but suppressed the differentiation of enteroendocrine cells,goblet cells and Paneth cells.However,the suppression of enteroendocrine cell and Paneth cell differentiation by SB202190 was alleviated at the presence of A8301.The glycogen synthase kinase 3 inhibitor(CHIR99021),valproic acid(VPA)alone and their combination promoted chicken intestinal organoid formation and enterocyte differentiation at the expense of the expression of Paneth cells and goblet cells.Chicken serum significantly improved organoid formation,especially in the presence of A8301,SB202190,CHIR99021,and VPA,but inhibited the differentiation of Paneth cells and enteroendocrine cells.Chicken serum at a concentration of 0.25%meets the requirement of chicken intestinal organoid development,and the beneficial effect of chicken serum on chicken intestinal organoid culture could not be replaced by fetal bovine serum and insulin-like growth factor-1.Moreover,commercial mouse organoid culture medium supplemented with A8301,SB202190,CHIR99021,VPA,and chicken serum promotes chicken organoid budding.Based on the chicken intestinal organoid model,we found that methionine deficiency mimicked by cycloleucine suppressed organoid formation and organoid size,and this effect was reinforced with increased cycloleucine concentrations.Methionine hydroxy analogue promoted regeneration of ISC but decreased cell differentiation compared with the results obtained with L-methionine.In conclusion,our results provide a potentially excellent guideline for chicken intestinal organoid culture and insights into methionine function in crypt development.展开更多
Two experiments were conducted to investigate the effects of phytonutrients(PN)on growth performance.antioxidant status,intestinal morphology,and nutrient utilization of birds fed low energy diets.In Exp.1.a total of ...Two experiments were conducted to investigate the effects of phytonutrients(PN)on growth performance.antioxidant status,intestinal morphology,and nutrient utilization of birds fed low energy diets.In Exp.1.a total of 1.440 one-day-old Ross 308 male broiler chickens were randomly divided into 3 treatment groups,with 16 replicates per treatment(48 pens;30 birds per pen).Birds in treatment 1 were fed diets with normal energy content(NE).Birds in treatment 2 were fed NE diet but with 60 kcal removed(LE).Birds in treatment 3 were assigned to LE diet supplemented with PN(LE + PN).Results indicated that LE diet increased feed conversion ratio(FCR)compared with NE from d 1 to 38.while LE + PN diet prevented this response(P= 0.02).At d 26.birds in the LE + PN group had the highest ileal and jejunal villus height to crypt depth(VH:CD)ratio.At d 39.PN supplementation improved ileal and jejunal VH:CD ratio,compared with LE group.Moreover,birds fed PN diets received a better economic profit,In Exp.2,360 one-day-old Ross 308 male broiler chickens were used in a metabolism study.The treatments used in Exp.2 were the same as those in Exp.1,with 4 replicates(pens)and 30 birds in each replicate.Dietary apparent metabolism energy(AME),energy and protein digestibility were determined between 21 and 28 d of age.Results showed that chickens fed LE + PN diet tended to have greater AME(P= 0.02)and nictrogen-corrected apparent metabolism energy(AMEn)(P= 0.03)than birds fed LE diets.It was concluded that LE+ PN showed a potential advantage to improve feed conversion and gut health of broilers,as well as economic profits.展开更多
Some veterinary drug residues in food products and environment have been widely regarded as severe threats to human health.Rapid and simultaneous detection methods are crucial to monitor and control veterinary drug us...Some veterinary drug residues in food products and environment have been widely regarded as severe threats to human health.Rapid and simultaneous detection methods are crucial to monitor and control veterinary drug usage.Here,we propose a fluorescence biosensor utilizing immunomagnetic beads(IMBs)and quantum dots(QDs)for the rapid and simultaneous detection of 1-adamantylamine(ADA),enrofloxacin(ENR)and tilmicosin(TIL)in raw chicken meat.A pretreatment method using sodium phosphotungstate–magnesium as extraction reagent was developed to simultaneously extract ADA,ENR and TIL from chicken meat with minor interference in background or response.By adding the IMBs modified with three types of antibodies and the QD-antigens modified with three types of BSA-antigens to sample,IMBs competitively conjugated to target antigens in a sample or QD-antigens.After magnetic separation,the residual QD-antigens were adopted to collect signals using fluorescence spectroscopy.Using QDs with well separated emission peaks,the detection of one type of targets was minorly interfered by the others.Under the optimum conditions,the biosensor exhibited the limit of detection of 0.96,3.32,and 3.17 ng/mL for ADA,ENR and TIL in chicken samples,respectively,as well as good specificity.Due to the way of direct collection of signals in extracts,the tedious and complicated multiple magnetic separation and signal amplification procedures in conventional methods were avoided,thus the procedures were significantly simplified,and the reduction of the operation time of 30 min for sample pretreatment and 40 min for detection part was achieved.The biosensor might be promising in the rapid,in-field and sensitive screening of multiple veterinary drugs to ensure agriculture and food safety.展开更多
基金This study was funded by the Key Laboratory of Feed and Livestock and Poultry Products Quality&Safety Control,Ministry of Agriculture(2021202201)Reform and Development Project of BAAFS(XMS202322).
文摘Background A deterioration in the meat quality of broilers has attracted much more attention in recent years.L-malic acid(MA)is evidenced to decrease meat drip loss in broilers,but the underlying molecular mechanisms are still unclear.It’s also not sure whether the outputs obtained under experimental conditions can be obtained in a com-mercial condition.Here,we investigated the effects and mechanisms of dietary MA supplementation on chicken meat drip loss at large-scale rearing.Results Results showed that the growth performance and drip loss were improved by MA supplementation.Meat metabolome revealed that L-2-aminoadipic acid,β-aminoisobutyric acid,eicosapentaenoic acid,and nicotinamide,as well as amino acid metabolism pathways connected to the improvements of meat quality by MA addition.The transcriptome analysis further indicated that the effect of MA on drip loss was also related to the proper immune response,evidenced by the enhanced B cell receptor signaling pathway,NF-κB signaling pathway,TNF signaling pathway,and IL-17 signaling pathway.Conclusions We provided evidence that MA decreased chicken meat drip loss under commercial conditions.Metabolome and transcriptome revealed a comprehensive understanding of the underlying mechanisms.Together,MA could be used as a promising dietary supplement for enhancing the water-holding capacity of chicken meat.
基金funded by the National Key R&D Program of China(2016YFD040040303).
文摘Coriander(Coriandrum sativum L.)is recognized for its antioxidant property,as a kind of natural phenolic-rich ingredient.Polycyclic aromatic hydrocarbons(PAHs)present a class of heat-driven hazards in foods,especially the processed meat.In this study,the effect of coriander root and leaf extract on the formation and inhibition of PAH8 in roasted duck wings was firstly investigated.Coriander root extract(CRE)and coriander leaf extract(CLE)with five concentration groups(200,400,600,800,1000 mg/L)were prepared respectively to marinate the duck wings.CRE marinade exhibited greater inhibitory effect on PAH8 formation in roasted duck wings that ranged from 65.0%-87.4%.The electron spin resonance study indicated a significantly positive correlation between PAH8 and free radical level,suggesting the participation of radicals in PAHs formation.Also,it was speculated that the inhibitory effect on PAH8 was related to the phenolic compounds identified in coriander marinades.CRE made greater inhibitory effect on the formation of PAH8 and could be considered as a kind of natural source to mitigate PAHs in heat-processed meat products.
基金This work was supported by the National Natural Science Found ation of China(32273000)the Qingdao Demonstration Project for People-benefit from Science and Techniques,China(23-2-8-xdny-14nsh and 24-2-8-xdny-4-nsh)+1 种基金the National Program of Undergraduate Innovation and Entrepreneurship,China(202310435039)the Open Project Fund of State Key Laboratory of Microbial Technology,China(M2023-03)。
文摘Senecavirus A(SVA)has a positive-sense,single-stranded RNA genome.Its 5´untranslated region harbors an internal ribosome entry site(IRES),comprising 10 larger or smaller stem-loop structures(including a pseudoknot)that have been demonstrated to be well conserved.However,it is still unclear whether each stem-loop subdomain,such as a single stem or loop,is also highly conserved.To clarify this issue in the present study,a set of 29 SVA cDNA clones were constructed by site-directed mutagenesis(SDM)on the IRES.The SDM-modified scenarios included:(1)stem-formed complementary sequences exchanging with each other;(2)loop transversion;(3)loop transition;and(4)point mutations.All cDNA clones were separately transfected into cells for rescuing viable viruses,whereas only four SVAs of interest could be recovered,and were genetically stable during 20 passages.One progeny grew significantly slower than the other three did.The dual-luciferase reporter assay showed that none of the SDM-modified IRESes significantly inhibited the IRES activity.Our previous study indicated that a single motif from any of the ten stem structures,if completely mutated,would cause the failure of virus recovery.Interestingly,our present study revealed three stem structures,whose individual complementary sequences could exchange with each other to rescue sequence-modifying SVAs.Moreover,one apical loop was demonstrated to have the ability to tolerate its own full-length transition,also having no impact on the recovery of sequence-modifying SVA.The present study suggested that not every stem-loop structure was strictly conserved in its conformation,while the full-length IRES itself was well conserved.This provides a new research direction on interaction between the IRES and many factors.
基金supported by grants from the Key Technologies Research on New Breed of Broiler Poultry by Integration of Breeding,Reproduction and Promotion(2021CXGC010805-02)Taishan Industry Leadership Talent Project of Shandong province in China(TSCY20190108)+1 种基金China Agriculture Research System of MOF and MARA(CARS-42)the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CXGC-IAS-09).
文摘Background Carcass traits are crucial for broiler ducks,but carcass traits can only be measured postmortem.Genomic selection(GS)is an effective approach in animal breeding to improve selection and reduce costs.However,the performance of genomic prediction in duck carcass traits remains largely unknown.Results In this study,we estimated the genetic parameters,performed GS using different models and marker densi-ties,and compared the estimation performance between GS and conventional BLUP on 35 carcass traits in an F2 population of ducks.Most of the cut weight traits and intestine length traits were estimated to be high and moder-ate heritabilities,respectively,while the heritabilities of percentage slaughter traits were dynamic.The reliability of genome prediction using GBLUP increased by an average of 0.06 compared to the conventional BLUP method.The Permutation studies revealed that 50K markers had achieved ideal prediction reliability,while 3K markers still achieved 90.7%predictive capability would further reduce the cost for duck carcass traits.The genomic relationship matrix nor-malized by our true variance method instead of the widely used 2pi(1-pi)could achieve an increase in prediction reliability in most traits.We detected most of the bayesian models had a better performance,especially for BayesN.Compared to GBLUP,BayesN can further improve the predictive reliability with an average of 0.06 for duck carcass traits.Conclusion This study demonstrates genomic selection for duck carcass traits is promising.The genomic prediction can be further improved by modifying the genomic relationship matrix using our proposed true variance method and several Bayesian models.Permutation study provides a theoretical basis for the fact that low-density arrays can be used to reduce genotype costs in duck genome selection.
基金supported by the National Key Research and Development Program of China(2018YFD0500402)the National Natural Science Foundation of China(No.31672431)the National Key Research and Development Program(2016YFD0700201)
文摘Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed to investigate the impact of dietary supplementation of extra-Ile on lipogenesis,fatty acid profile and lipid accumulation in skeletal muscle in finishing pigs.Methods: Forty-eight barrows with initial body weight of 77.0 ± 0.1 kg were allotted to one of two groups and fed diets containing 0.39%,0.53% standardized ileal digestible(SID) Ile with six replicates per treatment and four pigs per replicate for 30 d.Results: Dietary Ile intake significantly improved the intramuscular fat(IMF) content and monounsaturated fatty acid(MUFA) concentration in the skeletal muscle(P < 0.05),and decreased the drip loss and shear force(P < 0.05) without influencing the growth performance of pigs(P > 0.05).Moreover,the phosphorylation of adenosine monophosphate activated protein kinase α(AMPKα) and acetyl coenzyme A carboxylase(ACC) proteins that monitor lipid metabolism were decreased in skeletal muscle of pigs offered extra-Ile diet(P < 0.05).The mRNA expression of adipose-specific genes adipocyte determination and differentiation factor 1(ADD1),fatty acid synthase(FAS),and stearoyl-CoA desaturase(SCD) were upregulated and the activity of SCD was increased as well(P < 0.05).Conclusions: Surplus dietary Ile intake could increase IMF accumulation and MUFA synthesis in skeletal muscle through depressing the phosphorylation of AMPKα-ACC and stimulating the expression and activity of SCD,and increasing the capability of lipogenesis in skeletal muscle.
基金supported by the funding of the National Natural Science Foundation of China(32072752)the Southwest Minzu University Double World-Class Project,China(XM2023011)。
文摘Fasting is typically used before feeding metabolizable energy assessment in broilers.Previous studies have shown that fasting cause atrophy of the intestinal villus.Whether fasting affects intestinal permeability during refeeding by altering barrier function and nutrient absorption is of concern.Here,23-d-old broilers were randomly assigned to 5 treatments,fasted for 0,12,24,36,and 48 h,respectively,and then refed for 2 d,to study the impact of different duration of fasting on the intestinal regeneration and barrier function during refeeding.Results showed that the intestinal morphology in fasted birds was recovered in 2 d of refeeding at most.As fasting durations increased,enterocytes per intestinal villus were linearly and quadratically increased(both P<0.05),whereas goblet cells per intestinal villus was linearly decreased(both P<0.05).Besides,the mRNA level of lysozyme was linearly decreased as fasting durations increased during refeeding(both P<0.05),while quadratically increased mucin 2 was observed only after 1 d of refeeding(P<0.05).Linear increase effects were observed for claudin 2 and zonula occludens-1with increased fasting durations after 1 d of refeeding(all P<0.05),and linear and quadratical effects were observed for claudin 2 at 2 d of refeeding(both P<0.05).Besides,we found that intestinal permeability to creatinine,4 and 70 kD dextran were linearly and quadratically decreased with increased fasting durations at 6 h and 1 d of refeeding(all P<0.05).Furthermore,jejunum proteomic from birds refed for 6 h showed that birds fasted for 36 h showed increased antimicrobial peptides and upregulated retinol metabolism when compared to the nonfasted birds(P<0.05).Further study showed that retinyl ester catabolism was inhibited during fasting and enhanced during refeeding.Results of intestinal organoid culture showed that retinol benefits the cell proliferation and enterocyte differentiation.In conclusion,the intestinal permeability to small and large molecules was decreased during refeeding by strengthening the intestinal barrier function,and the activated retinol metabolism during refeeding is involved in the intestinal regeneration and strengthens the intestinal barrier.
基金the State Key Program of National Science Foundation of China(No.61836006)the National Natural Science Fund for Distinguished Young Scholar(No.61625204)+1 种基金the National Natural Science Foundation of China(Nos.62106161 and 61602328)the Key Research and Development Project of Sichuan(No.2019YFG0494).
文摘Fluidic Catalytic Cracking(FCC)is a complex petrochemical process affected by many highly non-linear and interrelated factors.Product yield analysis,flue gas desulfurization prediction,and abnormal condition warning are several key research directions in FCC.This paper will sort out the relevant research results of the existing Artificial Intelligence(AI)algorithms applied to the analysis and optimization of catalytic cracking processes,with a view to providing help for the follow-up research.Compared with the traditional mathematical mechanism method,the AI method can effectively solve the difficulties in FCC process modeling,such as high-dimensional,nonlinear,strong correlation,and large delay.AI methods applied in product yield analysis build models based on massive data.By fitting the functional relationship between operating variables and products,the excessive simplification of mechanism model can be avoided,resulting in high model accuracy.AI methods applied in flue gas desulfurization can be usually divided into two stages:modeling and optimization.In the modeling stage,data-driven methods are often used to build the system model or rule base;In the optimization stage,heuristic search or reinforcement learning methods can be applied to find the optimal operating parameters based on the constructed model or rule base.AI methods,including data-driven and knowledge-driven algorithms,are widely used in the abnormal condition warning.Knowledge-driven methods have advantages in interpretability and generalization,but disadvantages in construction difficulty and prediction recall.While the data-driven methods are just the opposite.Thus,some studies combine these two methods to obtain better results.
基金supported by the National Key R&D Program of China(2021ZD0113803)the"Pioneer"and"Leading Goose"R&D Program of Zhejiang (2022C02031)the National Natural Science Foundation of China (No. 31701424)
文摘Porcine epidemic diarrhea(PED)caused by porcine epidemic diarrhea virus(PEDV)is one of the most devastating diseases in the global pig industry due to its high mortality rate in piglets.Maternal vaccines can effectively enhance the gut-mammary gland-secretory IgA axis to boost lactogenic immunity and passive protection of nursing piglets against PEDV challenge.From 2017 to 2021,we collected 882 diarrhea samples from 303 farms in China to investigate the epidemiology of PEDV.The result showed that about 52.15%(158/303)of the farms were positive for PEDV with an overall detection rate of 63.95%(564/882)of the samples.The S1 fragments of S gene from 104 strains were sequenced for the phylogenetic analysis.A total of 71 PEDV strains(68.27%)sequenced in this study were clustered into the predominant G2c subgroup,while the newly-defined G2d strains(9.62%)were identified in three provinces of China.The NH-TA2020 strain of G2c subgroup was isolated and cultured,and its infection to piglets caused watery diarrhea within 24 h,indicating its strong pathogenicity.Oral administration of NH-TA2020 strain to pregnant gilts stimulated high levels of IgA antibody in colostrum.The piglets fed by the gilts above were challenged with NH-TA2020 strain or CH-HeB-RY-2020 strain from G2d subgroup,and the clinical symptoms and virus shedding were significantly reduced compared to the mock group.Our findings suggest that G2c subgroup is the predominant branch circulating in China from 2017 to 2021.Oral administration of NH-TA2020 enhances maternal IgA and lactogenic immune responses,which confer protection against the homologous and emerging G2d PEDV strains challenges in neonates.
基金supported by National Natural Science Foundation of China(no.31972599)the Key Research and Development Program of Sichuan Province(no.2018NZDZX0005)。
文摘Certain hormones play important roles in modulating mammalian reproductive behaviour.Daidzein is a well-known isoflavonic phytoestrogen that possesses oestrogenic activity.This study was conducted to probe the effects of daidzein supplementation in gestation diets on the reproductive performance in sows.A total of 120 multiparous sows(Landrace x Yorkshire)were randomly assigned to 2 groups(n=60)and fed either a base diet(control)or one containing 200 mg/kg daidzein during gestation.We discovered that daidzein supplementation significantly increased the total number of piglets born per litter and number of piglets born alive per litter(P<0.05),decreased the farrowing time(P<0.05)and increased the serum oestrogen and progesterone concentrations(P<0.05)at 35 d of gestation.Moreover,serum immunoglobulin G(IgG)concentration and superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)activities were higher in the daidzein-treated group than in the control group at35 d of gestation(P<0.05).Daidzein increased the serum SOD activity and total anti-oxidative capacity(T-AOC)at 85 d of gestation(P<0.05).Interestingly,daidzein elevated the expression levels of the sodium-coupled neutral amino acid transporter 1(SLC38 A1)and insulin-like growth factor 1(IGF-1)genes in the placenta(P<0.05).These results suggest that daidzein ingestion could improve sow reproductive performance by changing serum hormones,elevating anti-oxidative capacity and upregulating critical functional genes in the placenta.
文摘This study was conducted to evaluate the effects of feed form(mash and crumble-pellet) and feed particle size(fine, medium and coarse) on growth performance, carcass characteristics and digestive tract development of broilers. A total of 1,152 one day-old Ross 308 mixed-sex broilers were used in a factorial arrangement(2×3) based on a completely randomized design with six replicates of 32 birds each.Higher average daily gain(ADG) and average daily feed intake(ADFI) were observed(P < 0.01) for birds fed the crumble-pellet diets(CPD) than for those fed the mash diets(MD) during starter, grower and the entire experiment period. From d 1 to 40, birds fed CPD had a higher(P < 0.01) body weight(BW) than those fed MD. Birds fed CPD had a lower(P < 0.01) feed:gain ratio(F:G) during the starter phase than those fed MD. Medium or coarse particle size increased(P < 0.01) ADG and ADFI during the starter phase, but birds fed fine particle size diets had lower(P < 0.01) F:G during the grower phase. In MD,medium and coarse particle sizes resulted in higher(P < 0.05) BW, ADG and ADFI than fine particle size during the whole experiment. In CPD, particle size had no significant effect on growth performance, as indicated by a feed form × particle size interaction(P < 0.05). At 41 days of age, ten birds per treatment were randomly selected and killed for slaughter yields and digestive tract characteristics determination.It was shown that particle size and feed form alone had no significant effect on slaughter yields, so changes was the feed form × particle size interaction. The relative empty weight of the gizzard was greater(P < 0.01) and the relative length of the ileum was longer(P < 0.05) in birds fed MD than in those fed CPD. Overall, CPD improved growth performance during the entire period of the study with effects being less evident during the finisher phase than during the starter and grower phases, and the effect of feed particle size varied depending on feed form.
基金This work was supported by the founding of the National Natural Science Foundation of China(No.32072752,No.31772620,No.31970814)the System for Poultry Production Technology,Beijing Agriculture Innovation Consortium(Project Number:BAIC04-2020)Natural Key R&D Project of China(2020YFA0113200).
文摘Methionine and its hydroxy analogue(MHA)have been shown to benefit mouse intestinal regeneration.The intestinal organoid is a good model that directly reflects the impact of certain nutrients or chemicals on intestinal development.Here,we aimed to establish a chicken intestinal organoid culture method first and then use the model to explore the influence of methionine deficiency and MHA on intestinal organoid development.The results showed that 125-mm cell strainer exhibited the highest efficiency for chicken embryo crypt harvesting.We found that transforming growth factor-b inhibitor(A8301)supplementation promoted enterocyte differentiation at the expense of the proliferation of intestinal stem cells(ISC).The mitogen-activated protein kinase p38 inhibitor(SB202190)promoted intestinal organoid formation and enterocyte differentiation but suppressed the differentiation of enteroendocrine cells,goblet cells and Paneth cells.However,the suppression of enteroendocrine cell and Paneth cell differentiation by SB202190 was alleviated at the presence of A8301.The glycogen synthase kinase 3 inhibitor(CHIR99021),valproic acid(VPA)alone and their combination promoted chicken intestinal organoid formation and enterocyte differentiation at the expense of the expression of Paneth cells and goblet cells.Chicken serum significantly improved organoid formation,especially in the presence of A8301,SB202190,CHIR99021,and VPA,but inhibited the differentiation of Paneth cells and enteroendocrine cells.Chicken serum at a concentration of 0.25%meets the requirement of chicken intestinal organoid development,and the beneficial effect of chicken serum on chicken intestinal organoid culture could not be replaced by fetal bovine serum and insulin-like growth factor-1.Moreover,commercial mouse organoid culture medium supplemented with A8301,SB202190,CHIR99021,VPA,and chicken serum promotes chicken organoid budding.Based on the chicken intestinal organoid model,we found that methionine deficiency mimicked by cycloleucine suppressed organoid formation and organoid size,and this effect was reinforced with increased cycloleucine concentrations.Methionine hydroxy analogue promoted regeneration of ISC but decreased cell differentiation compared with the results obtained with L-methionine.In conclusion,our results provide a potentially excellent guideline for chicken intestinal organoid culture and insights into methionine function in crypt development.
基金financially supported by Shandong Taishan Industry Leading Talent Project(LJNY2015006)Major Special Science and Technology Project of Sichuan Province(2018NZDX0005)
文摘Two experiments were conducted to investigate the effects of phytonutrients(PN)on growth performance.antioxidant status,intestinal morphology,and nutrient utilization of birds fed low energy diets.In Exp.1.a total of 1.440 one-day-old Ross 308 male broiler chickens were randomly divided into 3 treatment groups,with 16 replicates per treatment(48 pens;30 birds per pen).Birds in treatment 1 were fed diets with normal energy content(NE).Birds in treatment 2 were fed NE diet but with 60 kcal removed(LE).Birds in treatment 3 were assigned to LE diet supplemented with PN(LE + PN).Results indicated that LE diet increased feed conversion ratio(FCR)compared with NE from d 1 to 38.while LE + PN diet prevented this response(P= 0.02).At d 26.birds in the LE + PN group had the highest ileal and jejunal villus height to crypt depth(VH:CD)ratio.At d 39.PN supplementation improved ileal and jejunal VH:CD ratio,compared with LE group.Moreover,birds fed PN diets received a better economic profit,In Exp.2,360 one-day-old Ross 308 male broiler chickens were used in a metabolism study.The treatments used in Exp.2 were the same as those in Exp.1,with 4 replicates(pens)and 30 birds in each replicate.Dietary apparent metabolism energy(AME),energy and protein digestibility were determined between 21 and 28 d of age.Results showed that chickens fed LE + PN diet tended to have greater AME(P= 0.02)and nictrogen-corrected apparent metabolism energy(AMEn)(P= 0.03)than birds fed LE diets.It was concluded that LE+ PN showed a potential advantage to improve feed conversion and gut health of broilers,as well as economic profits.
基金funded by the Walmart Foundation(0402-70013-21-0000)supported by the Walmart Food Safety Collaboration Center
文摘Some veterinary drug residues in food products and environment have been widely regarded as severe threats to human health.Rapid and simultaneous detection methods are crucial to monitor and control veterinary drug usage.Here,we propose a fluorescence biosensor utilizing immunomagnetic beads(IMBs)and quantum dots(QDs)for the rapid and simultaneous detection of 1-adamantylamine(ADA),enrofloxacin(ENR)and tilmicosin(TIL)in raw chicken meat.A pretreatment method using sodium phosphotungstate–magnesium as extraction reagent was developed to simultaneously extract ADA,ENR and TIL from chicken meat with minor interference in background or response.By adding the IMBs modified with three types of antibodies and the QD-antigens modified with three types of BSA-antigens to sample,IMBs competitively conjugated to target antigens in a sample or QD-antigens.After magnetic separation,the residual QD-antigens were adopted to collect signals using fluorescence spectroscopy.Using QDs with well separated emission peaks,the detection of one type of targets was minorly interfered by the others.Under the optimum conditions,the biosensor exhibited the limit of detection of 0.96,3.32,and 3.17 ng/mL for ADA,ENR and TIL in chicken samples,respectively,as well as good specificity.Due to the way of direct collection of signals in extracts,the tedious and complicated multiple magnetic separation and signal amplification procedures in conventional methods were avoided,thus the procedures were significantly simplified,and the reduction of the operation time of 30 min for sample pretreatment and 40 min for detection part was achieved.The biosensor might be promising in the rapid,in-field and sensitive screening of multiple veterinary drugs to ensure agriculture and food safety.
