Effects of early postnatal gastric and colonic microbiota transplantation on piglet gut health

Background Diarrhea is a major cause of reduced growth and mortality in piglets during the suckling and weaning periods and poses a major threat to the global pig industry.Diarrhea and gut dysbiosis may in part be prevented via improved early postnatal microbial colonization of the gut.To secure better postnatal gut colonization,we hypothesized that transplantation of colonic or gastric content from healthy donors to newborn recipients would prevent diarrhea in the recipients in the post-weaning period.Our objective was to examine the impact of transplanting colonic or gastric content on health and growth parameters and paraclinical parameters in recipient single-housed piglets exposed to a weaning transition and challenged with enterotoxigenic Escherichia coli(ETEC).Methods Seventy-two 1-day-old piglets were randomized to four groups:colonic microbiota transplantation(CMT,n=18),colonic content filtrate transplantation(CcFT,n=18),gastric microbiota transplantation(GMT,n=18),or saline(CON,n=18).Inoculations were given on d 2 and 3 of life,and all piglets were milk-fed until weaning(d 20)and shortly after challenged with ETEC(d 24).We assessed growth,diarrhea prevalence,ETEC concentration,organ weight,blood parameters,small intestinal morphology and histology,gut mucosal function,and microbiota composition and diversity.Results Episodes of diarrhea were seen in all groups during both the milk-and the solid-feeding phase,possibly due to stress associated with single housing.However,CcFT showed lower diarrhea prevalence on d 27,28,and 29 compared to CON(all P<0.05).CcFT also showed a lower ETEC prevalence on d 27(P<0.05).CMT showed a higher alpha diversity and a difference in beta diversity compared to CON(P<0.05).Growth and other paraclinical endpoints were similar across groups.Conclusion In conclusion,only CcFT reduced ETEC-related post-weaning diarrhea.However,the protective effect was marginal,suggesting that higher doses,more effective modalities of administration,longer treatment periods,and better donor quality should be explored by future research to optimize the protective effects of transplantation.

Dietary supplementation of zinc oxide modulates intestinal functionality during the post-weaning period in clinically healthy piglets

Background To improve our understanding of host and intestinal microbiome interaction,this research investigated the effects of a high-level zinc oxide in the diet as model intervention on the intestinal microbiome and small intestinal functionality in clinically healthy post-weaning piglets.In study 1,piglets received either a high concentration of zinc(Zn)as zinc oxide(Zn O,Zn,2,690 mg/kg)or a low Zn concentration(100 mg/kg)in the diet during the post weaning period(d 14–23).The effects on the piglet's small intestinal microbiome and functionality of intestinal tissue were investigated.In study 2,the impact of timing of the dietary zinc intervention was investigated,i.e.,between d 0–14 and/or d 14–23 post weaning,and the consecutive effects on the piglet's intestinal functionality,here referring to microbiota composition and diversity and gene expression profiles.Results Differences in the small intestinal functionality were observed during the post weaning period between piglets receiving a diet with a low or high concentration Zn O content.A shift in the microbiota composition in the small intestine was observed that could be characterized as a non-pathological change,where mainly the commensals inter-changed.In the immediate post weaning period,i.e.,d 0–14,the highest number of differentially expressed genes(DEGs)in intestinal tissue were observed between animals receiving a diet with a low or high concentration Zn O content,i.e.,23 DEGs in jejunal tissue and 11 DEGs in ileal tissue.These genes are involved in biological processes related to immunity and inflammatory responses.For example,genes CD59 and REG3G were downregulated in the animals receiving a diet with a high concentration Zn O content compared to low Zn O content in both jejunum and ileum tissue.In the second study,a similar result was obtained regarding the expression of genes in intestinal tissue related to immune pathways when comparing piglets receiving a diet with a high concentration Zn O content compared to low Zn O content.Conclusions Supplementing a diet with a pharmaceutical level of Zn as Zn O for clinically healthy post weaning piglets influences various aspects intestinal functionality,in particular in the first two weeks post-weaning.The model intervention increased both the alpha diversity of the intestinal microbiome and the expression of a limited number of genes linked to the local immune system in intestinal tissue.The effects do not seem related to a direct antimicrobial effect of Zn O.

Association of Serum Folate and Vitamin B_(12) Concentrations with Obesity in Chinese Children and Adolescents

Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents.Methods A cross-sectional study was conducted including 3,079 Chinese children and adolescents,aged 6 to 17 years,from Jiangsu,China.Anthropometric indices,such as,children's body mass index(BMI),BMI z-scores,waist circumference,and waist-to-height ratio were utilized.Multivariable linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B12 levels with anthropometric indices and odds of obesity.Results We observed that serum vitamin B12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity[odds ratio(OR)=0.68;95%confidence interval(CI)=0.59,0.78]and abdominal obesity(OR=0.68;95%CI=0.60,0.77).When compared to participants with both serum vitamin levels in the two middle quartiles,those with both serum folate and vitamin B12 levels in the highest quartile were less prone to general(OR=0.31,95%CI=0.19,0.50)or abdominal obesity(OR=0.46,95%CI=0.31,0.67).Conversely,participants with vitamin B12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity(OR=2.06,95%CI=1.09,3.91).Conclusion Higher serum vitamin B12 concentrations,but not serum folate concentrations,were associated with lower odds of childhood obesity.Children and adolescents with high levels of vitamin B12 and folate were less likely to be obese.

Cardiovascular risk burden,dementia risk and brain structural imaging markers:a study from UK Biobank

Background Cardiovascular risk burden is associated with dementia risk and neurodegeneration-related brain structure,while the role of genetics and incident cardiovascular disease(CVD)remains unclear.Aims To examine the association of overall cardiovascular risk burden with the risk of major dementia subtypes and volumes of related brain regions in a large sample,and to explore the role of genetics and CVD onset.Methods A prospective study among 354 654 participants free of CVD and dementia(2006-2010,mean age 56.4 years)was conducted within the UK Biobank,with brain magnetic resonance imaging(MRl)measurement availablefor 15104participants since 2014.CVD risk burden was evaluated by the Framingham General Cardiovascular Risk Score(FGCRS).Dementia diagnosis was ascertained from inpatient and death register data.Results Overamedian 12.0-yearfollow-up,3998 all-cause dementia cases were identified.Higher FGCRS was associated with increasedall-cause dementia risk after adjusting for demographic,major lifestyle,clinical factors and the polygenic risk score(PRS)of Alzheimer's disease.Comparing the high versus low tertile of FGCRS,the odds ratios(ORs)and 95%confidence intervals(Cls)were 1.26(1.12 to 1.41)for all-cause dementia,1.67(1.33 to 2.09)for Alzheimer's disease and 1.53(1.07 to 2.16)for vascular dementia(all p_(treng)<0.05).Incident stroke and coronary heart disease accounted for 14%(95%Cl:9% to 21%)of the association between FGCRS and all-cause dementia.Interactions were not detected for FGCRS and PRS on the risk of any dementia subtype.We observed an 83%(95%Cl:47%to 128%)higher all-cause dementia risk comparing the high-high versus low-low FGCRS-PRS category.For brain volumes,higher FGCRS was associated with greater log-transformed white matter hyperintensities,smaller cortical volume and smaller grey matter volume.Conclusions Our findings suggest that the positive association of cardiovascular risk burden with dementia risk also applies to major dementia subtypes.The association of cardiovascular risk burden with all-cause dementia is largely independent of CVD onset and genetic predisposition to dementia.

Predicting nitrogen use efficiency,nitrogen loss and dry matter intake of individual dairy cows in late lactation by including mid‑infrared spectra of milk samples

Background Nitrate leaching to groundwater and surface water and ammonia volatilization from dairy farms have negative impacts on the environment.Meanwhile,the increasing demand for dairy products will result in more pollution if N losses are not controlled.Therefore,a more efficient,and environmentally friendly production system is needed,in which nitrogen use efficiency(NUE)of dairy cows plays a key role.To genetically improve NUE,extensively recorded and cost-effective proxies are essential,which can be obtained by including mid-infrared(MIR)spectra of milk in prediction models for NUE.This study aimed to develop and validate the best prediction model of NUE,nitrogen loss(NL)and dry matter intake(DMI)for individual dairy cows in China.Results A total of 86 lactating Chinese Holstein cows were used in this study.After data editing,704 records were obtained for calibration and validation.Six prediction models with three different machine learning algorithms and three kinds of pre-processed MIR spectra were developed for each trait.Results showed that the coefficient of determination(R2)of the best model in within-herd validation was 0.66 for NUE,0.58 for NL and 0.63 for DMI.For external validation,reasonable prediction results were only observed for NUE,with R2 ranging from 0.58 to 0.63,while the R2 of the other two traits was below 0.50.The infrared waves from 973.54 to 988.46 cm−1 and daily milk yield were the most important variables for prediction.Conclusion The results showed that individual NUE can be predicted with a moderate accuracy in both within-herd and external validations.The model of NUE could be used for the datasets that are similar to the calibration dataset.The prediction models for NL and 3-day moving average of DMI(DMI_a)generated lower accuracies in within-herd validation.Results also indicated that information of MIR spectra variables increased the predictive ability of models.Additionally,pre-processed MIR spectra do not result in higher accuracy than original MIR spectra in the external validation.These models will be applied to large-scale data to further investigate the genetic architecture of N efficiency and further reduce the adverse impacts on the environment after more data is collected.

Breeding against mycorrhizal symbiosis:Modern cotton (Gossypium hirsutum L.) varieties perform more poorly than older varieties except at very high phosphorus supply levels

Cotton (Gossypium hirsutum L.) is an importantfiber cash crop,but its root traits related to phosphorus (P) acquisition,including mycorrhizal root traits,are poorly understood.Eight cotton varieties bred in northwestern China that were released between 1950 and 2013 were grown in pots with or without one arbuscular mycorrhizal fungal (AMF) species(Funneliformis mosseae) at three P supply levels (0,50 and 300 mg P as KH_(2)PO_(4)kg^(-1)).Eleven root traits were measured and calculated after 7 wk of growth.The more recent accessions had smaller root diameters,acquired less P and produced less biomass,indicating an (inadvertent) varietal selection for thinner roots that provided less cortical space for AMF,which then increased the need for a high P fertilizer level.At the two lower P levels,the mycorrhizal plants acquired more P and produced more biomass than non-mycorrhizal plants (3.2 vs.0.9 mg P per plant;1.8 vs.0.9 g biomass per plant at P_(0);14.5 vs.1.7 mg P per plant;and 4.7 vs.1.6 g biomass per plant at P_(50)).At the highest P level,the mycorrhizal plants acquired more P than non-mycorrhizal plants (18.8 vs.13.4 mg per P plant),but there was no difference in biomass (6.2 vs.6.3 g per plant).At the intermediate P level,root diameter was significantly positively correlated with shoot biomass,P concentration and the P content of mycorrhizal plants.The results of our study support the importance of the outsourcing model of P acquisition in the root economics space framework.Inadvertent varietal selection in the last decades,resulting in thinner roots and a lower benefit from AMF,has led to a lower productivity of cotton varieties at moderate P supply (i.e.,when mycorrhizal,the average biomass of older varieties 5.0 g per plant vs.biomass of newer varieties 4.4 g per plant),indicating the need to rethink cotton breeding efforts in order to achieve high yields without very high P input.One feasible way to solve the problem of inadvertent varietal selection for cotton is to be aware of the trade-offs between the root do-it-yourself strategy and the outsourcing towards AMF strategy,and to consider both morphological and mycorrhizal root traits when breeding cotton varieties.

Responses of breeding waterbird communities to environmental changes in subsidence wetlands in the North China Plain

In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative habitats.However,waterbirds are facing various threats in these artificial wetlands,due to dramatic environmental changes induced by anthropogenic activities.Exploring the effects of these changes on the temporal dynamics of the waterbird communities can help understand how waterbirds adapt to environmental changes and thus formulate effective management and conservation plans.In this study,we carried out field surveys on waterbirds and environmental factors across 20 subsidence wetlands created by underground coal mining in the Huainan coal mining area in the breeding seasons of 2016 and 2021.We predicted that the waterbird assemblages(i.e.,number of individuals,species richness,Shannon-Wiener diversity,Pielou evenness and species composition) differed between the two years,and that these differences were correlated with the temporal changes in environmental factors.Across the surveyed wetlands,we recorded 26 waterbird species in 2016 and 23 in 2021.For individual wetlands,the number of waterbird individuals and species richness increased by 71.6% and 20.1%,respectively,over the five years,with no changes in Shannon-Wiener diversity and Pielou evenness.The overall increase in the number of bird individuals was mainly caused by an increase in vegetation gleaners and gulls that adapt well to anthropogenic activities.The species composition was significantly different between the two years,which was mainly caused by changes in the number of individuals of dominant species under influence of changes in human activities.For most wetlands,the temporal pairwiseβ-diversities could be explained by species turnover rather than nestedness,probably due to high mobility of waterbird species and dramatic changes in local environments.Our study suggests that waterbird communities could respond to environmental changes in subsidence wetlands,providing important implications for waterbird conservation in human-dominated artificial wetlands.

川西北草原高原鼢鼠密度调查及引诱剂与D型肉毒素复合毒饵对其的灭效

目的为了掌握川西北草原高原鼢鼠Myospalax baileyi Pallas种群密度和提高D型肉毒素杀灭高原鼢鼠的效率,于2013年和2014年在位于川西北草原的红原县草原调查了高原鼢鼠的密度,并研究了不同引诱剂的引诱效果及引诱剂与D型肉毒素复合毒饵对高原鼢鼠的灭效。方法采用开洞堵洞法和连续捕净法调查高原鼢鼠密度;选用菜籽油和花生油配制引诱剂,然后用引诱剂和D型肉毒素配制复合毒饵,采用开洞堵洞法研究其灭效。结果红原县草原高原鼢鼠密度2013年为39.70只/hm2,2014年为42.14只/hm^2,平均密度为40.92只/hm^2,危害程度为Ⅳ级(严重危害)。菜籽油引诱剂取食率为72.2%,花生油引诱剂取食率为60.0%,二者间差异有高度统计学意义(P<0.01)。未添加引诱剂的D型肉毒素毒饵的灭效为77.2%,添加引诱剂的灭效为89.8%,二者间差异有高度统计学意义(P<0.01),但是复合毒饵各组内灭效差异无统计学意义(P>0.05)。结论使用浓度0.10%的D型肉毒素与引诱剂配制复合毒饵,可以显著提高D型肉毒素对高原鼢鼠的灭效。

Effects of undigested protein-rich ingredients on polarised small intestinal organoid monolayers

Here, we describe the use of monolayers of intestinal epithelial cells derived from intestinal organoids and transcriptomics to investigate the direct effects of dietary protein sources on epithelial function. Mechanically dissociated 3 D organoids of mouse duodenum were used to generate a polarized epithelium containing all cell types found in the tissue of origin. The organoid-derived cell monolayers were exposed to 4%(w/v) of ‘undigested(non-hydrolysed)-soluble' fraction of protein sources used as feed ingredients [soybean meal(SBM) and casein], or alternative protein sources(spray dried plasma protein, and yellow meal worm), or controls for 6 h prior to RNA isolation and transcriptomics. All protein sources altered expression of unique biological processes in the epithelial cells. Exposure of intestinal organoids to SBM downregulated expression of retinol and retinoid metabolic processes as well as cholesterol and lipid biosynthetic pathways, consistent with the reported hypotriglyceridaemic effect of soy protein in vivo. These findings support the use of intestinal organoids as models to evaluate complex interactions between dietary ingredients and the intestinal epithelium and highlights some unique host effects of alternative protein sources in animal feed and potentially human food.

High-density SNP-based genetic maps for the parents of an outcrossed and a selfed tetraploid garden rose cross, inferred from admixed progeny using the 68k rose SNP array

Dense genetic maps create a base for QTL analysis of important traits and future implementation of marker-assisted breeding.In tetraploid rose,the existing linkage maps include<300 markers to cover 28 linkage groups(4 homologous sets of 7 chromosomes).Here we used the 68k WagRhSNP Axiom single-nucleotide polymorphism(SNP)array for rose,in combination with SNP dosage calling at the tetraploid level,to genotype offspring from the garden rose cultivar‘Red New Dawn’.The offspring proved to be not from a single bi-parental cross.In rose breeding,crosses with unintended parents occur regularly.We developed a strategy to separate progeny into putative populations,even while one of the parents was unknown,using principle component analysis on pairwise genetic distances based on sets of selected SNP markers that were homozygous,and therefore uninformative for one parent.One of the inferred populations was consistent with self-fertilization of‘Red New Dawn’.Subsequently,linkage maps were generated for a bi-parental and a self-pollinated population with‘Red New Dawn’as the common maternal parent.The densest map,for the selfed parent,had 1929 SNP markers on 25 linkage groups,covering 1765.5 cM at an average marker distance of 0.9 cM.Synteny with the strawberry(Fragaria vesca)genome was extensive.Rose ICM1 corresponded to F.vesca pseudochromosome 7(Fv7),ICM4 to Fv4,ICM5 to Fv3,ICM6 to Fv2 and ICM7 to Fv5.Rose ICM2 corresponded to parts of F.vesca pseudochromosomes 1 and 6,whereas ICM3 is syntenic to the remainder of Fv6.

Breeding melon(Cucumis melo)with resistance to powdery mildew and downy mildew

Melon(Cucumis melo L.)production is often restricted by a plethora of pests and diseases,including powdery mildew and downy mildew caused respectively by the fungal species Podosphaera xanthii/Golovinomyces orontii and oomycete species Pseudoperonospora cubensis.Many efforts have been directed on identification of resistant sources by screening(wild)melon germplasm.In the current review,we summarized such efforts from various publications of the last 50 plus years.Resistance to powdery mildew has been identified in 239 melon accessions and downy mildew resistance in 452 accessions of both C.melo and the wild relative species C.figarei.Among the resistance sources,C.melo var.cantalupensis accessions PMR 45,PMR 5,PMR 6,and WMR 29 as well as C.melo var.momordica accessions PI 124111,PI 124112,and PI 414723 have been considered as the most valuable germplasm because multiple resistance genes have been identified from these accessions and are widely used in melon resistance breeding.Further genetic mapping in a number of resistant sources has enabled identification of 25 dominant genes,two recessive genes and seven QTLs conferring powdery mildew resistance,as well as eight dominant genes and 11 QTLs for downy mildew resistances.Based on the reported sequences of associated markers,we anchored physically(many of)these genes and QTLs to chromosomes of the melon cv.DHL92 genome.In addition to presenting a comprehensive overview on powdery mildew and downy mildew resistance in(wild)melon germplasm,we suggest strategies aiming at breeding melon with durable and broad-spectrum resistance to pathogens and pests.

Responses of Lowland, Upland and Aerobic Rice Genotypes to Water Limitation During Different Phases

Rice yield reduction due to water limitation depends on its severity and duration and on the phenological stage of its occurrence.We exposed three contrasting rice genotypes,IR64,UPLRi7 and Apo(adapted to lowland,upland and aerobic conditions,respectively),to three water regimes(puddle,100%and 60%field capacity)in pots during the vegetative(GSI),flowering(GSII)and grain filling(GSIII)stages.Stress at all the three stages significantly reduced yield especially in lowland genotype IR64.Effect of water limitation was more severe at GSII than at the other two stages.Stress at GSI stage reduced both source activity(leaf area and photosynthetic rate)and sink capacity(tiller number or panicle number per pot).When stress was imposed at GSII,spikelet fertility was most affected in all the three genotypes.In both GSII and GSIII,although leaf area was constant in all the three water regimes,estimated relative whole-plant photosynthesis was strongly associated with yield reduction.Reduced photosynthesis due to stress at any given stage was found to have direct impact on yield.Compared to the other genotypes,Apo had deeper roots and maintained a better water relation,thus,higher carbon gain and spikelet viability,and ultimately,higher biomass and productivity under water-limited conditions.Therefore,screening for these stage-dependent adaptive mechanisms is crucial in breeding for sustained rice production under water limitation.

Common bean SNP alleles and candidate genes affecting photosynthesis under contrasting water regimes

Water deficit is a major worldwide constraint to common bean(Phaseolus vulgaris L.)production,being photosynthesis one of the most affected physiological processes.To gain insights into the genetic basis of the photosynthetic response of common bean under water-limited conditions,a collection of 158 Portuguese accessions was grown under both well-watered and water-deficit regimes.Leaf gas-exchange parameters were measured and photosynthetic pigments quantified.The same collection was genotyped using SNP arrays,and SNP-trait associations tested considering a linear mixed model accounting for the genetic relatedness among accessions.A total of 133 SNP-trait associations were identified for net CO 2 assimilation rate,transpiration rate,stomatal conductance,and chlorophylls a and b,carotenes,and xanthophyll contents.Ninety of these associations were detected under water-deficit and 43 under well-watered conditions,with only two associations common to both treatments.Identified candidate genes revealed that stomatal regulation,protein translocation across membranes,redox mechanisms,hormone,and osmotic stress signaling were the most relevant processes involved in common bean response to water-limited conditions.These candidates are now preferential targets for common bean water-deficit-tolerance breeding.Additionally,new sources of water-deficit tolerance of Andean,Mesoamerican,and admixed origin were detected as accessions valuable for breeding,and not yet explored.

ABA-mediated regulation of leaf and root hydraulic conductance in tomato grown at elevated CO2 is associated with altered gene expression of aquaporins

Elevated CO_(2)concentration in the air(e[CO_(2)])decreases stomatal density(SD)and stomatal conductance(gs)where abscisic acid(ABA)may play a role,yet the underlying mechanism remains largely elusive.We investigated the effects of e[CO_(2)](800 ppm)on leaf gas exchange and water relations of two tomato(Solanum lycopersicum)genotypes,Ailsa Craig(WT)and its ABA-deficient mutant(flacca).Compared to plants grown at ambient CO_(2)(400 ppm),e[CO_(2)]stimulated photosynthetic rate in both genotypes,while depressed the gs only in WT.SD showed a similar response to e[CO_(2)]as gs,although the change was not significant.e[CO_(2)]increased leaf and xylem ABA concentrations and xylem sap pH,where the increases were larger in WT than in flacca.Although leaf water potential was unaffected by CO_(2)growth environment,e[CO_(2)]lowered osmotic potential,hence tended to increase turgor pressure particularly for WT.e[CO_(2)]reduced hydraulic conductance of leaf and root in WT but not in flacca,which was associated with downregulation of gene expression of aquaporins.It is concluded that ABA-mediated regulation of gs,SD,and gene expression of aquaporins coordinates the whole-plant hydraulics of tomato grown at different CO_(2)environments.

Cereal type and combined xylanase/glucanase supplementation influence the cecal microbiota composition in broilers

Dietary fiber-degrading enzyme supplementation in broilers aims at off-setting the anti-nutritive effect of non-starch polysaccharides and at promoting broiler health.Recently,we demonstrated that xylanase/glucanase addition in wheat-based diet improved nutrient digestibility,arabinoxylan fermentability and broiler growth.Conversely,maize arabinoxylan was found to be recalcitrant to xylanase action.These findings suggested that enzyme-mediated improvement of nutrient digestion and carbohydrate fermentation depended on the cereal type present in the diet,and may have contributed to broiler growth.Hence,we aimed at further investigating the link between dietary enzymes and carbohydrate fermentation in broilers,by studying the impact of enzyme supplementation in cereal-based diets,to the microbial communities in the ileum and ceca of broilers.For that purpose,96 one-day-old male broilers were randomly reared in two pens and received either wheat-based or maize-based starter and grower diets.At d 20,the broilers were randomly assigned to one out of four dietary treatments.The broilers received for 8 d the wheat-based or maize-based finisher diet as such(Control treatments;WC,MC)or supplemented with a xylanase/glucanase combination(Enzyme treatments;WE,ME).At d 28,samples from the digestive tract were collected,and the ileal and cecal microbiota composition was determined by 16S ribosomal RNA gene amplicon sequencing.A similar phylogenetic(alpha)diversity was observed among the four treatments,both in the ileal and the cecal samples.Furthermore,a similar microbial composition in the ileum(beta diversity)was observed,with lactobacilli being the predominant community for all treatments.In contrast,both cereal type and enzyme supplementation were found to influence cecal communities.The type of cereal(i.e.,wheat or maize)explained 47% of the total variation in microbial composition in the ceca.Further stratifying the analysis per cereal type revealed differences in microbiota composition between WC and WE,but not between MC and ME.Furthermore,the prevalence of beneficial genera,such as Faecalibacterium and Blautia,in the ceca of broilers fed wheat-based diets coincided with arabinoxylan accumulation.These findings indicated that fermentable arabinoxylan and arabinoxylo-oligosaccharides released by dietary xylanase may play an important role in bacterial metabolism.

The dark side of technological advances in analysis of microbial ecosystems

Recent technological advances mean that samples from animal experiments may be analysed more cheaply,more easily and with a much greater return of data than previously.Research groups are frequently faced with a choice of continuing to use established technology in which they may have made a significant investment of time and resources,and have significant amounts of reference data,or switching to new technology where reference data may be limited.Apart from cost,the choice needs to be based on a comparison between the increase in data available from future experiments by switching and the value of comparison with reference data from historical experiments analysed with earlier technology.One approach to this problem is to ensure that sufficient quantity and variety of samples are taken from each experiment and appropriately stored to allow re-establishment of a sufficiently large reference set and to avoid the need to repeat animal experiments.The establishment of ‘biobanks' of experimental material will require funding for infrastructure,consistent storage of metadata and,importantly,horizon-scanning to ensure that samples are taken appropriately for techniques which will become accessible in future.Such biobanks are a recognised resource in human medicine,where the value of samples increases as more analysis is carried out and added to the metadata.

Interpreting forest diversity-productivity relationships:volume values,disturbance histories and alternative inferences

Understanding the relationship between stand-level tree diversity and productivity has the potential to inform the science and management of forests.History shows that plant diversity-productivity relationships are challenging to interpret—and this remains true for the study of forests using non-experimental field data.Here we highlight pitfalls regarding the analyses and interpretation of such studies.We examine three themes:1)the nature and measurement of ecological productivity and related values;2)the role of stand history and disturbance in explaining forest characteristics;and 3)the interpretation of any relationship.We show that volume production and true productivity are distinct,and neither is a demonstrated proxy for economic values.Many stand characteristics,including diversity,volume growth and productivity,vary intrinsically with succession and stand history.We should be characterising these relationships rather than ignoring or eliminating them.Failure to do so may lead to misleading conclusions.To illustrate,we examine the study which prompted our concerns—Liang et al.(Science 354:aaf8957,2016)—which developed a sophisticated global analysis to infer a worldwide positive effect of biodiversity(tree species richness)on“forest productivity”(stand level wood volume production).Existing data should be able to address many of our concerns.Critical evaluations will improve understanding.

The ability to manipulate ROS metabolism in pepper may affect aphid virulence

Myzus persicae has severe economic impact on pepper(Capsicum)cultivation.Previously,we identified two populations of M.persicae,NL and SW,that were avirulent and virulent,respectively on C.baccatum accession PB2013071.The transcriptomics approach used in the current study,which is the first study to explore the pepper−aphid interaction at the whole genome gene expression level,revealed genes whose expression is differentially regulated in pepper accession PB2013071 upon infestation with these M.persicae populations.The NL population induced ROS production genes,while the SW population induced ROS scavenging genes and repressed ROS production genes.We also found that the SW population can induce the removal of ROS which accumulated in response to preinfestion with the NL population,and that preinfestation with the SW population significantly improved the performance of the NL population.This paper supports the hypothesis that M.persicae can overcome the resistance in accession PB2013071 probably because of its ability to manipulate plant defense response especially the ROS metabolism and such ability may benefit avirulent conspecific aphids.

Maternal-derived antibodies hinder the antibody response to H9N2 AIV inactivated vaccine in the field

The H9N2 subtype avian influenza virus(AIV)inactivated vaccine has been used extensively in poultry farms,but it often fails to stimulate a sufficiently high immune response in poultry in the field,although it works well in laboratory experiments;hence,the virus still causes economic damage every year and poses a potential threat to public health.Based on surveillance data collected in the field,we found that broilers with high levels of maternal-derived antibodies(MDAs)against H9N2 virus did not produce high levels of antibodies after vaccination with a commercial H9N2 inactivated vaccine.In contrast,specific pathogen-free(SPF)chickens without MDAs responded efficiently to that vaccination.When MDAs were mimicked by administering passively transferred antibodies(PTAs)into SPF chickens in the laboratory,similar results were observed:H9N2-specific PTAs inhibited humoral immunity against the H9N2 inactivated vaccine,suggesting that H9N2-specific MDAs might hinder the generation of antibodies when H9N2 inactivated vaccine was used.After challenge with homologous H9N2 virus,the virus was detected in oropharyngeal swabs of the vaccinated and unvaccinated chickens with PTAs but not in the vaccinated chickens without PTAs,indicating that H9N2-specific MDAs were indeed one of the reasons for H9N2 inactivated vaccine failure in the field.When different titers of PTAs were used to mimic MDAs in SPF chickens,high(HI=12 log2)and medium(HI=log 9 log2)titers of PTAs reduced the generation of H9N2-specific antibodies after the first vaccination,but a booster dose would induce a high and faster humoral immune response even of PTA interference.This study strongly suggested that high or medium titers of MDAs might explain H9N2 inactivated vaccine failure in the field.

Liming reduces soil phosphorus availability but promotes yield and P uptake in a double rice cropping system

Liming is often applied to alleviate soil acidification and increase crop yield on acidic soils,but its effect on soil phosphorus(P)availability is unclear,particularly in rice paddies.The objective of this study was to examine the effect of liming on rice production,yield and P uptake in a three-year field experiment in a double rice cropping system in subtropical China.We also conducted an incubation experiment to investigate the direct effect of liming on soil available P and phosphatase activities on paddy soils in the absence of plants.In the incubation experiment,liming reduced soil P availability(measured as Olsenextractable P)by 14–17%and inhibited the activity of soil acid phosphatase.Nonetheless,lime application increased grain yield,biomass,and P uptake in the field.Liming increased grain yield and P uptake more strongly for late rice(26 and 21%,respectively)than for early rice(15 and 8%,respectively).Liming reduced the concentration of soil available P in the field as well,reflecting the increase in rice P uptake and the direct negative effect of liming on soil P availability.Taken together,these results suggest that by stimulating rice growth,liming can overcome direct negative effects on soil P availability and increase plant P uptake in this acidic paddy soil where P is not the limiting factor.