The development of high-performance and cost-efficient catalysts holds great significance in facilitating oxygen reduction reaction(ORR),which is a pivotal process in next-generation energy storage devices,such as alu...The development of high-performance and cost-efficient catalysts holds great significance in facilitating oxygen reduction reaction(ORR),which is a pivotal process in next-generation energy storage devices,such as aluminum-air batteries.Transition metal sulfides have been proposed as promising non-noble metal ORR catalysts.However,achieving platinum(Pt)-comparable activity remains a challenge.Herein,a Co-doping-triggered electronic reconfiguration strategy is reported to tune the charge distribution and coordination state of ZnS nanoparticles anchored on N,S co-doped carbon(ZnS/NSC),thereby optimizing the intermediate adsorption kinetics and promoting ORR activity.The half-wave potential of 0.87 V as well as 100-h continuous durability are obtained by Co-doped ZnS/NSC in alkaline media.In addition,the solid-state aluminum-air battery is further assembled by using Co-doped ZnS/NSC as a cathode catalyst,achieving a maximum peak density of 100 mW·cm^(−2) and discharge duration over 55 h.Density functional theory(DFT)calculations reveal that high electronegative Co-doping is beneficial for the construct of charge-transfer avenue and optimization of intermediate adsorption procedure.This study presents an efficient approach for preparing metal sulfides with high catalytic activity toward ORR in flexible metal-air batteries.展开更多
Background Energy deficiency is a leading cause of the high pre-weaning mortality of neonatal piglets in the swine industry.Thus,optimal energy metabolism is of crucial importance for improving the survivability of ne...Background Energy deficiency is a leading cause of the high pre-weaning mortality of neonatal piglets in the swine industry.Thus,optimal energy metabolism is of crucial importance for improving the survivability of neonatal piglets.The effective utilization of milk fat as primary energy is indispensably required.Methods Pregnant sows(n=27)were randomly assigned into 3 treatments.Each treatment received a standard diet(3,265 kcal ME/kg)supplemented with either 0,0.25%or 0.5%clofibrate(w/w)from d 107 of gestation to d 7 of lacta-tion.The effects of maternal clofibrate on their milk fatty acid(FA)and performance of the piglets were evaluated.The evaluations were performed via measuring sow productive performance,milk FA composition,and hepatic FA oxida-tion of the piglets at birth and d 1,7,14 and 19 after birth.Results Maternal supplementation of clofibrate had no effect on reproductive performance of the sows at farrowing and weaning(P>0.05).However,the mortality at weaning was reduced for piglets from sows with 0.25%of clofi-brate,and the average weekly(and daily)gain was higher in piglets from sows that received clofibrate than sows without clofibrate in the first week(P<0.0001).Maternal clofibrate increased percentage of milk C12:0 and C14:0 FAs but decreased C18:2 and n-6 polyunsaturated FAs.Maternal clofibrate also increased plasma ketone body levels and hepatic FA oxidation measured at the first day of birth,but the increase was not detected in piglets on d 7,14 or 19.Clofibrate was not detected in milk collected from the clofibrate-treated sows.The percentage of FA oxidation decreased,and the percentage of FA esterification increased with increasing in postnatal age.Supplemental carni-tine increased FA oxidation regardless of succinate dehydrogenase inhibition,and the increase had no effect on FA esterification.Conclusions Maternal supplementation of clofibrate during late gestation and early lactation increases hepatic FA oxidative metabolism at birth and improves growth performance of newborn piglets.Maternal clofibrate transfer to suckling piglets via milk was not detected.Carnitine availability is critical for piglets to maintain a high FA oxidation rate during the suckling period.展开更多
Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in ...Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in the total hydrogen storage capacity due to“dead weight.”Here,we synthesize an optimized N-doped porous carbon(rN-pC)without heavy metal as supporting scaffold to confine Mg/MgH_(2) nanoparticles(Mg/MgH_(2)@rN-pC).rN-pC with 60 wt%loading capacity of Mg(denoted as 60 Mg@rN-pC)can adsorb and desorb 0.62 wt%H_(2) on the rN-pC scaffold.The nanoconfined MgH_(2) can be chemically dehydrided at 175℃,providing~3.59 wt%H_(2) with fast kinetics(fully dehydrogenated at 300℃ within 15 min).This study presents the first realization of nanoconfined Mg-based system with adsorption-active scaffolds.Besides,the nanoconfined MgH_(2) formation enthalpy is reduced to~68 kJ mol^(−1) H_(2) from~75 kJ mol^(−1) H_(2) for pure MgH_(2).The composite can be also compressed to nanostructured pellets,with volumetric H_(2) density reaching 33.4 g L^(−1) after 500 MPa compression pressure,which surpasses the 24 g L^(−1) volumetric capacity of 350 bar compressed H_(2).Our approach can be implemented to the design of hybrid H_(2) storage materials with enhanced capacity and desorption rate.展开更多
Two experiments were conducted to investigate the effect of in ovo zinc(Zn)injection on the embryonic development,tissue Zn contents,antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler...Two experiments were conducted to investigate the effect of in ovo zinc(Zn)injection on the embryonic development,tissue Zn contents,antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders.Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection.A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design.The eggs were injected with 0.1 mL sterilized water at 3,6 and 9 embryonic days of incubation(E3,E6 and E9)or non-injection(the control),respectively.The results from experiment 1 showed that E3 and E6 injections increased(P〈0.05)the embryonic mortalities,and decreased(P〈0.05)hatchabilities compared to the non-injected control,but no differences(P〉0.05)between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability.The findings suggest that the E9 is the optimal embryonic age for early in ovo injection.In experiment 2,a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design.The eggs were injected with 0(the negative control),50,100,150,200,or 250μg Zn/egg as reagent grade ZnSO4.7H20 in a 0.1-mL solution,or non-injection(the positive control),respectively at E9-10.The results from the experiment 2 demonstrated that no differences(P〉0.05)among 50 and 100μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability,however,the injection of 200μg Zn/egg increased(P〈0.05)the embryonic mortality,and injections of 150 and 200μg Zn/egg decreased(P〈0.05)hatchabilities compared with the controls.The embryonic tibia Zn contents at E20 were increased(P〈0.05)by injections of 150,200 and 250μg Zn/egg.Zinc injection did not affect(P〉0.05)malonaldehyde(MDA)contents,copper-and Zn-containing superoxide dismutase(CuZnSOD)activities and mRNA expression levels in the liver and heart of chick embryos at E15 and E20.Compared with the negative control,injections of 50,150 and 200μg Zn/egg up-regulated(P〈0.05)themetallothionein(MT)mRNA expression levels in the embryonic liver at E20.These results indicated that in ovo Zn injections increased Zn contents in the embryonic tibia and MT mRNA expression levels in the embryonic liver at E20,however,injections of 150-200μg Zn/egg were harmful to the embryonic development.展开更多
This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers....This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein.展开更多
Background： Intake of colostrum after birth is essential to stimulate intestinal growth and function, and to provide systemic immunological protection via absorption of Immunoglobulin G （IgG）. The birth order and w...Background： Intake of colostrum after birth is essential to stimulate intestinal growth and function, and to provide systemic immunological protection via absorption of Immunoglobulin G （IgG）. The birth order and weight of 745 piglets （from 75 litters） were recorded during a one-week period of farrowing. Only pigs weighing greater than 0.68 kg birth weight were chosen for the trial. Sow colostrum was collected during parturition, and piglets were bled between 48 and 72 hours post-birth. Piglet serum IgG and colostral IgG concentrations were determined by radial immunodiffusion. Results： Sow parity had a significant （P 〈 0.001） effect on sow colostral IgG concentration, being 5% higher in multiparous females. Sow colostral IgG concentration explained 6% and piglet birth order accounted for another 4% of the variation observed in piglet serum IgG concentration （P 〈 0.05）; however, birth weight had no detectable effect. Piglet serum IgG concentration had both a linear （P 〈 0.05） and quadratic effect （P 〈 0.05） on % survival. Piglets with 1,000 mg/dl serum IgG or less （n=24） had a 67% survival; whereas, piglets with IgG concentrations between 2250 to 2500 mg/dl （n=247） had a 91% survival. Birth order had no detectable effect on survival, but birth weight had a positive linear effect （P 〈 0.05）. Piglets weighing 0.9 kg （n = 107） at birth had a 68% survival rate, and those weighing 1.6 kg （n = 158） had an 89% survival. Conclusion： We found that the combination of sow colostrum IgG concentration and birth order can account for 10% of the variation of piglet serum IgG concentration and that piglets with less than 1,000 mg/dl IgG serum concentration and weight of 0.9 kg at birth had low survival rate when compared to their larger siblings. The effective management of colostrum uptake in neonatal piglets in the first 24 hrs post-birth may potentially improve survival from birth to weaning.展开更多
Background: Respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2(supporting both inflammation and resolution) makes it a potent regulator of immune...Background: Respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2(supporting both inflammation and resolution) makes it a potent regulator of immune cell function. Therefore, the use of dietary long chain n-6 PUFA to enhance PGE2 effects merits investigation.Methods: Day-old pigs(n = 60) were allotted to one of three dietary groups for 21 d(n = 20/diet), and received either a control diet(CON, arachidonate = 0.5% of total fatty acids), an arachidonate(ARA)-enriched diet(LC n-6,ARA = 2.2%), or an eicosapentaenoic(EPA)-enriched diet(LC n-3, EPA = 3.0%). Alveolar macrophages and lung parenchymal tissue were collected for fatty acid analysis. Isolated alveolar macrophages were stimulated with LPS in situ for 24 h, and m RNA was isolated to assess markers associated with inflammation and eicosanoid production.Culture media were collected to assess PGE2 secretion. Oxidative burst in macrophages was measured by: 1)oxygen consumption and extracellular acidification(via Seahorse), 2) cytoplasmic oxidation and 3) nitric oxide production following 4, 18, and 24 h of LPS stimulation.Results: Concentration of ARA(% of fatty acids, w/w) in macrophages from pigs fed LC n-6 was 86% higher than CON and 18% lower in pigs fed LC n-3(P < 0.01). Following LPS stimulation, abundance of COX-2 and TNF-α mRNA(P < 0.0001), and PGE2 secretion(P < 0. 01) were higher in LC n-6 PAM vs. CON. However, ALOX5 abundance was1.6-fold lower than CON. Macrophages from CON and LC n-6 groups were 4-fold higher in ALOX12/15 abundance(P < 0.0001) compared to LC n-3. Oxygen consumption and extracellular acidification rates increased over 4 h following LPS stimulation(P < 0.05) regardless of treatment. Similarly, increases in cytoplasmic oxidation(P < 0.001)and nitric oxide production(P < 0.002) were observed after 18 h of LPS stimulation but were unaffected by diet.Conclusions: We infer that enriching diets with arachidonic acid may be an effective means to enhance a stronger innate immunologic response to respiratory challenges in neonatal pigs. However, further work is needed to examine long-term safety, clinical efficacy and economic viability.展开更多
Free-standing and fexible air electrodes with long-lasting bifunctional activities for both the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)are crucial to the development of wearable Zn-air rec...Free-standing and fexible air electrodes with long-lasting bifunctional activities for both the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)are crucial to the development of wearable Zn-air rechargeable batteries.In this work,we synthesize a fexible air electrode consisting of 3D nanoporous N-doped graphene with trimodal shells and Ni particles through repeated chemical vapor deposition(CVD)and acidic etching processes.Our results indicate that such trimodal graphene morphology significantly enhances the active N-dopant sites and graphene-coated Ni surface,which consequentially boosts both the ORR and OER activities,as well as catalytic durability.First-principles density functional theory(DFT)calculations reveal the synergetic effects between the Ni and the N-doped graphene;namely,the Ni nanoparticles boost the bifunctional activities of the coated N-doped graphene,and in turn the graphene-covering layers enhance the stability of Ni.Thanks to the better protection from the triple graphene shells,our trimodal N-doped graphene/Ni-based Zn-air battery can be stably discharged/recharged beyond 2500 h with low overpotentials.It is reasonable to expect that such freestanding trimodal graphene/Ni would be promising in many fexible energy conversion/storage devices.展开更多
In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos wa...In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.展开更多
Background： To induce peroxisomal proliferator-activated receptor α（PPARα） expression and increase milk fat utilization in pigs at birth, the effect of maternal feeding of the PPARα agonist, clofibrate（2-（4-ch...Background： To induce peroxisomal proliferator-activated receptor α（PPARα） expression and increase milk fat utilization in pigs at birth, the effect of maternal feeding of the PPARα agonist, clofibrate（2-（4-chlorophenoxy）-2-methyl-propanoic acid, ethyl ester）, on fatty acid oxidation was examined at ful-term delivery（0 h） and 24 h after delivery in this study.Each group of pigs（n = 10） was delivered from pregnant sows fed a commercial diet with or without 0.8% clofibrate for the last 7 d of gestation. Blood samples were col ected from the utero-ovarian artery of the sows and the umbilical cords of the pigs as they were removed from the sows by C-section on day 113 of gestation.Results： HPLC analysis identified that clofibric acid was present in the plasma of the clofibrate-fed sow（~4.2 μg/m L）and its offspring（~1.5 μg/m L）. Furthermore, the maternal-fed clofibrate had no impact on the liver weight of the pigs at 0 h and 24 h, but hepatic fatty acid oxidation examined in fresh homogenates showed that clofibrate increased（P 〈 0.01）^14C-accumulation in CO2 and acid soluble products 2.9-fold from [1-^14C]-oleic acid and 1.6-fold from[1-^14C]-lignoceric acid respectively. Correspondingly, clofibrate increased fetal hepatic carnitine palmitoyltransferase（CPT）and acyl-Co A oxidase（ACO） activities by 36% and 42% over controls（P 〈 0.036）. The m RNA abundance of CPT I was 20-fold higher in pigs exposed to clofibrate（P 〈 0.0001） but no differences were detected for ACO and PPARα m RNA between the two groups.Conclusion： These data demonstrate that dietary clofibrate is absorbed by the sow, crosses the placental membrane, and enters fetal circulation to induce hepatic fatty acid oxidation by increasing the CPT and ACO activities of the newborn.展开更多
基金financially sponsored by the National Natural Science Foundation of China(Nos.52302039 and 52301043)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515110676)+2 种基金Shenzhen Science and Technology Program(Nos.JCYJ20220531095404009,RCBS20221008093057027 and GXWD20231129113217001)the Postdoctoral Research Startup Expenses of Shenzhen(No.NA25501001)Shenzhen Introduce High-level Talents and Scientific Research Startup Founds(No.NA11409005).
文摘The development of high-performance and cost-efficient catalysts holds great significance in facilitating oxygen reduction reaction(ORR),which is a pivotal process in next-generation energy storage devices,such as aluminum-air batteries.Transition metal sulfides have been proposed as promising non-noble metal ORR catalysts.However,achieving platinum(Pt)-comparable activity remains a challenge.Herein,a Co-doping-triggered electronic reconfiguration strategy is reported to tune the charge distribution and coordination state of ZnS nanoparticles anchored on N,S co-doped carbon(ZnS/NSC),thereby optimizing the intermediate adsorption kinetics and promoting ORR activity.The half-wave potential of 0.87 V as well as 100-h continuous durability are obtained by Co-doped ZnS/NSC in alkaline media.In addition,the solid-state aluminum-air battery is further assembled by using Co-doped ZnS/NSC as a cathode catalyst,achieving a maximum peak density of 100 mW·cm^(−2) and discharge duration over 55 h.Density functional theory(DFT)calculations reveal that high electronegative Co-doping is beneficial for the construct of charge-transfer avenue and optimization of intermediate adsorption procedure.This study presents an efficient approach for preparing metal sulfides with high catalytic activity toward ORR in flexible metal-air batteries.
基金Animal Nutrition,Growth and Lactation(grant no.2015–67015-23245/project accession no.1005855)Animal Health and Production and Animal Products(grant no.2023–67015-39663/1030033)from the USDA National Institute of Food and AgricultureNorth Carolina Agricultural Research Hatch projects 1016618 and 02780.
文摘Background Energy deficiency is a leading cause of the high pre-weaning mortality of neonatal piglets in the swine industry.Thus,optimal energy metabolism is of crucial importance for improving the survivability of neonatal piglets.The effective utilization of milk fat as primary energy is indispensably required.Methods Pregnant sows(n=27)were randomly assigned into 3 treatments.Each treatment received a standard diet(3,265 kcal ME/kg)supplemented with either 0,0.25%or 0.5%clofibrate(w/w)from d 107 of gestation to d 7 of lacta-tion.The effects of maternal clofibrate on their milk fatty acid(FA)and performance of the piglets were evaluated.The evaluations were performed via measuring sow productive performance,milk FA composition,and hepatic FA oxida-tion of the piglets at birth and d 1,7,14 and 19 after birth.Results Maternal supplementation of clofibrate had no effect on reproductive performance of the sows at farrowing and weaning(P>0.05).However,the mortality at weaning was reduced for piglets from sows with 0.25%of clofi-brate,and the average weekly(and daily)gain was higher in piglets from sows that received clofibrate than sows without clofibrate in the first week(P<0.0001).Maternal clofibrate increased percentage of milk C12:0 and C14:0 FAs but decreased C18:2 and n-6 polyunsaturated FAs.Maternal clofibrate also increased plasma ketone body levels and hepatic FA oxidation measured at the first day of birth,but the increase was not detected in piglets on d 7,14 or 19.Clofibrate was not detected in milk collected from the clofibrate-treated sows.The percentage of FA oxidation decreased,and the percentage of FA esterification increased with increasing in postnatal age.Supplemental carni-tine increased FA oxidation regardless of succinate dehydrogenase inhibition,and the increase had no effect on FA esterification.Conclusions Maternal supplementation of clofibrate during late gestation and early lactation increases hepatic FA oxidative metabolism at birth and improves growth performance of newborn piglets.Maternal clofibrate transfer to suckling piglets via milk was not detected.Carnitine availability is critical for piglets to maintain a high FA oxidation rate during the suckling period.
基金supported by the National Key R&D Program of China(2022YFB3803700)National Natural Science Foundation of China(52171186)+1 种基金Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)support from“Zhiyuan Honor Program”for doctoral students,Shanghai Jiao Tong University.
文摘Nanoconfinement is a promising approach to simultaneously enhance the thermodynamics,kinetics,and cycling stability of hydrogen storage materials.The introduction of supporting scaffolds usually causes a reduction in the total hydrogen storage capacity due to“dead weight.”Here,we synthesize an optimized N-doped porous carbon(rN-pC)without heavy metal as supporting scaffold to confine Mg/MgH_(2) nanoparticles(Mg/MgH_(2)@rN-pC).rN-pC with 60 wt%loading capacity of Mg(denoted as 60 Mg@rN-pC)can adsorb and desorb 0.62 wt%H_(2) on the rN-pC scaffold.The nanoconfined MgH_(2) can be chemically dehydrided at 175℃,providing~3.59 wt%H_(2) with fast kinetics(fully dehydrogenated at 300℃ within 15 min).This study presents the first realization of nanoconfined Mg-based system with adsorption-active scaffolds.Besides,the nanoconfined MgH_(2) formation enthalpy is reduced to~68 kJ mol^(−1) H_(2) from~75 kJ mol^(−1) H_(2) for pure MgH_(2).The composite can be also compressed to nanostructured pellets,with volumetric H_(2) density reaching 33.4 g L^(−1) after 500 MPa compression pressure,which surpasses the 24 g L^(−1) volumetric capacity of 350 bar compressed H_(2).Our approach can be implemented to the design of hybrid H_(2) storage materials with enhanced capacity and desorption rate.
基金supported by the Key International Cooperation Program of the National Natural Science Foundation of China(31110103916)the Agricultural Science and Technology Innovation Program,China(ASTIPIAS08)the earmaked fund for the China Agriculture Research System(CARS-42)
文摘Two experiments were conducted to investigate the effect of in ovo zinc(Zn)injection on the embryonic development,tissue Zn contents,antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders.Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection.A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design.The eggs were injected with 0.1 mL sterilized water at 3,6 and 9 embryonic days of incubation(E3,E6 and E9)or non-injection(the control),respectively.The results from experiment 1 showed that E3 and E6 injections increased(P〈0.05)the embryonic mortalities,and decreased(P〈0.05)hatchabilities compared to the non-injected control,but no differences(P〉0.05)between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability.The findings suggest that the E9 is the optimal embryonic age for early in ovo injection.In experiment 2,a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design.The eggs were injected with 0(the negative control),50,100,150,200,or 250μg Zn/egg as reagent grade ZnSO4.7H20 in a 0.1-mL solution,or non-injection(the positive control),respectively at E9-10.The results from the experiment 2 demonstrated that no differences(P〉0.05)among 50 and 100μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability,however,the injection of 200μg Zn/egg increased(P〈0.05)the embryonic mortality,and injections of 150 and 200μg Zn/egg decreased(P〈0.05)hatchabilities compared with the controls.The embryonic tibia Zn contents at E20 were increased(P〈0.05)by injections of 150,200 and 250μg Zn/egg.Zinc injection did not affect(P〉0.05)malonaldehyde(MDA)contents,copper-and Zn-containing superoxide dismutase(CuZnSOD)activities and mRNA expression levels in the liver and heart of chick embryos at E15 and E20.Compared with the negative control,injections of 50,150 and 200μg Zn/egg up-regulated(P〈0.05)themetallothionein(MT)mRNA expression levels in the embryonic liver at E20.These results indicated that in ovo Zn injections increased Zn contents in the embryonic tibia and MT mRNA expression levels in the embryonic liver at E20,however,injections of 150-200μg Zn/egg were harmful to the embryonic development.
基金supported by the National Natural Science Foundation of China(31501977)the Sichuan Provincial Key R&D Project China(22ZDYF0194)the Double World-Class Project of Southwest Minzu University China(XM2023010)。
文摘This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein.
文摘Background： Intake of colostrum after birth is essential to stimulate intestinal growth and function, and to provide systemic immunological protection via absorption of Immunoglobulin G （IgG）. The birth order and weight of 745 piglets （from 75 litters） were recorded during a one-week period of farrowing. Only pigs weighing greater than 0.68 kg birth weight were chosen for the trial. Sow colostrum was collected during parturition, and piglets were bled between 48 and 72 hours post-birth. Piglet serum IgG and colostral IgG concentrations were determined by radial immunodiffusion. Results： Sow parity had a significant （P 〈 0.001） effect on sow colostral IgG concentration, being 5% higher in multiparous females. Sow colostral IgG concentration explained 6% and piglet birth order accounted for another 4% of the variation observed in piglet serum IgG concentration （P 〈 0.05）; however, birth weight had no detectable effect. Piglet serum IgG concentration had both a linear （P 〈 0.05） and quadratic effect （P 〈 0.05） on % survival. Piglets with 1,000 mg/dl serum IgG or less （n=24） had a 67% survival; whereas, piglets with IgG concentrations between 2250 to 2500 mg/dl （n=247） had a 91% survival. Birth order had no detectable effect on survival, but birth weight had a positive linear effect （P 〈 0.05）. Piglets weighing 0.9 kg （n = 107） at birth had a 68% survival rate, and those weighing 1.6 kg （n = 158） had an 89% survival. Conclusion： We found that the combination of sow colostrum IgG concentration and birth order can account for 10% of the variation of piglet serum IgG concentration and that piglets with less than 1,000 mg/dl IgG serum concentration and weight of 0.9 kg at birth had low survival rate when compared to their larger siblings. The effective management of colostrum uptake in neonatal piglets in the first 24 hrs post-birth may potentially improve survival from birth to weaning.
基金funded in part by the North Carolina State University Agricultural Foundation,USDA-NIFA Animal Health Program
文摘Background: Respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2(supporting both inflammation and resolution) makes it a potent regulator of immune cell function. Therefore, the use of dietary long chain n-6 PUFA to enhance PGE2 effects merits investigation.Methods: Day-old pigs(n = 60) were allotted to one of three dietary groups for 21 d(n = 20/diet), and received either a control diet(CON, arachidonate = 0.5% of total fatty acids), an arachidonate(ARA)-enriched diet(LC n-6,ARA = 2.2%), or an eicosapentaenoic(EPA)-enriched diet(LC n-3, EPA = 3.0%). Alveolar macrophages and lung parenchymal tissue were collected for fatty acid analysis. Isolated alveolar macrophages were stimulated with LPS in situ for 24 h, and m RNA was isolated to assess markers associated with inflammation and eicosanoid production.Culture media were collected to assess PGE2 secretion. Oxidative burst in macrophages was measured by: 1)oxygen consumption and extracellular acidification(via Seahorse), 2) cytoplasmic oxidation and 3) nitric oxide production following 4, 18, and 24 h of LPS stimulation.Results: Concentration of ARA(% of fatty acids, w/w) in macrophages from pigs fed LC n-6 was 86% higher than CON and 18% lower in pigs fed LC n-3(P < 0.01). Following LPS stimulation, abundance of COX-2 and TNF-α mRNA(P < 0.0001), and PGE2 secretion(P < 0. 01) were higher in LC n-6 PAM vs. CON. However, ALOX5 abundance was1.6-fold lower than CON. Macrophages from CON and LC n-6 groups were 4-fold higher in ALOX12/15 abundance(P < 0.0001) compared to LC n-3. Oxygen consumption and extracellular acidification rates increased over 4 h following LPS stimulation(P < 0.05) regardless of treatment. Similarly, increases in cytoplasmic oxidation(P < 0.001)and nitric oxide production(P < 0.002) were observed after 18 h of LPS stimulation but were unaffected by diet.Conclusions: We infer that enriching diets with arachidonic acid may be an effective means to enhance a stronger innate immunologic response to respiratory challenges in neonatal pigs. However, further work is needed to examine long-term safety, clinical efficacy and economic viability.
基金financially supported by the Development and Reform Commission of Shenzhen Municipalitythe National Natural Science Foundation of China(Grant Nos.51702031,51871077)+1 种基金the Shenzhen Fundamental Research Program(Grant Nos.JCYJ20180306171644942,JCYJ20180507184623297,KQJSCX20180328165656256)the Innovation Project from Harbin Institute of Technology。
文摘Free-standing and fexible air electrodes with long-lasting bifunctional activities for both the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)are crucial to the development of wearable Zn-air rechargeable batteries.In this work,we synthesize a fexible air electrode consisting of 3D nanoporous N-doped graphene with trimodal shells and Ni particles through repeated chemical vapor deposition(CVD)and acidic etching processes.Our results indicate that such trimodal graphene morphology significantly enhances the active N-dopant sites and graphene-coated Ni surface,which consequentially boosts both the ORR and OER activities,as well as catalytic durability.First-principles density functional theory(DFT)calculations reveal the synergetic effects between the Ni and the N-doped graphene;namely,the Ni nanoparticles boost the bifunctional activities of the coated N-doped graphene,and in turn the graphene-covering layers enhance the stability of Ni.Thanks to the better protection from the triple graphene shells,our trimodal N-doped graphene/Ni-based Zn-air battery can be stably discharged/recharged beyond 2500 h with low overpotentials.It is reasonable to expect that such freestanding trimodal graphene/Ni would be promising in many fexible energy conversion/storage devices.
基金supported by the Key International Cooperation Program of the National Natural Science Foundation of China (31110103916)the National Natural Science Foundation of China (31272465)+1 种基金the Agricultural Science and Technology Innovation Program,China (ASTIP-IAS08)the China Agriculture Research System (CARS-42)
文摘In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.
文摘Background： To induce peroxisomal proliferator-activated receptor α（PPARα） expression and increase milk fat utilization in pigs at birth, the effect of maternal feeding of the PPARα agonist, clofibrate（2-（4-chlorophenoxy）-2-methyl-propanoic acid, ethyl ester）, on fatty acid oxidation was examined at ful-term delivery（0 h） and 24 h after delivery in this study.Each group of pigs（n = 10） was delivered from pregnant sows fed a commercial diet with or without 0.8% clofibrate for the last 7 d of gestation. Blood samples were col ected from the utero-ovarian artery of the sows and the umbilical cords of the pigs as they were removed from the sows by C-section on day 113 of gestation.Results： HPLC analysis identified that clofibric acid was present in the plasma of the clofibrate-fed sow（~4.2 μg/m L）and its offspring（~1.5 μg/m L）. Furthermore, the maternal-fed clofibrate had no impact on the liver weight of the pigs at 0 h and 24 h, but hepatic fatty acid oxidation examined in fresh homogenates showed that clofibrate increased（P 〈 0.01）^14C-accumulation in CO2 and acid soluble products 2.9-fold from [1-^14C]-oleic acid and 1.6-fold from[1-^14C]-lignoceric acid respectively. Correspondingly, clofibrate increased fetal hepatic carnitine palmitoyltransferase（CPT）and acyl-Co A oxidase（ACO） activities by 36% and 42% over controls（P 〈 0.036）. The m RNA abundance of CPT I was 20-fold higher in pigs exposed to clofibrate（P 〈 0.0001） but no differences were detected for ACO and PPARα m RNA between the two groups.Conclusion： These data demonstrate that dietary clofibrate is absorbed by the sow, crosses the placental membrane, and enters fetal circulation to induce hepatic fatty acid oxidation by increasing the CPT and ACO activities of the newborn.
