3709 research outputs found
Sort by
Nutrition strategies to counteract sarcopenia: a focus on protein, LC n-3 PUFA and precision nutrition
No full textDiminished skeletal muscle strength and size, termed sarcopenia, contributes substantially to physical disability, falls, dependence and reduced quality of life among older people. Physical activity and nutrition are the cornerstones of sarcopenia prevention and treatment. The optimal daily protein intake required to preserve muscle mass and function among older adults is a topic of intense scientific debate. Older adults require protein intakes about 67 % higher than their younger counterparts to maximally stimulate postprandial muscle protein synthesis rates. In addition, evidence suggests a possible benefit of increasing protein intake above the population reference intake (0⋅83 g/kg/d) on lean mass and, when combined with exercise training, muscle strength. In addition to protein quantity, protein quality, the pattern of protein intake over the day and specific amino acids (i.e. leucine) represent key considerations. Long-chain n-3 PUFA (LC n-3 PUFA) supplementation has been shown to enhance muscle protein synthesis rates, increase muscle mass and function and augment adaptations to resistance training in older adults. Yet, these effects are not consistent across all studies. Emerging evidence indicates that an older person's dietary, phenotypic and behavioural characteristics may modulate the efficacy of protein and LC n-3 PUFA interventions for promoting improvements in muscle mass and function, highlighting the potential inadequacy of a ‘one-size-fits-all’ approach. The application of personalised or precision nutrition to sarcopenia represents an exciting and highly novel field of research with the potential to help resolve inconsistencies in the literature and improve the efficacy of dietary interventions for sarcopenia
Bioinformatic approaches for studying the microbiome of fermented food
Get PDFpeer-reviewedHigh-throughput DNA sequencing-based approaches continue to revolutionise our understanding of microbial ecosystems, including those associated with fermented foods. Metagenomic and metatranscriptomic approaches are state-of-the-art biological profiling methods and are employed to investigate a wide variety of characteristics of microbial communities, such as taxonomic membership, gene content and the range and level at which these genes are expressed. Individual groups and consortia of researchers are utilising these approaches to produce increasingly large and complex datasets, representing vast populations of microorganisms. There is a corresponding requirement for the development and application of appropriate bioinformatic tools and pipelines to interpret this data. This review critically analyses the tools and pipelines that have been used or that could be applied to the analysis of metagenomic and metatranscriptomic data from fermented foods. In addition, we critically analyse a number of studies of fermented foods in which these tools have previously been applied, to highlight the insights that these approaches can provide.European Union’s Horizon 2020 research and innovation programm
The effect of polyvinylpyrrolidone addition on microstructure, surface aspects, the glass transition temperature and structural strength of honey and coconut sugar powders
Get PDFpeer-reviewedDeep knowledge of the microstructure and physicochemical properties of polymeric food systems, such as honey powders (HP) and coconut sugars (CS), has practical importance for industry and end users. This study investigated the effect of polyvinylpyrrolidone (PVP) addition on microstructure, roughness, glass transition, α-relaxation temperatures and structural strength (S) of anhydrous complex carbohydrates mixtures. The addition of PVP slightly increased the glass transition and α-relaxation temperature for HP and CS systems as high molecular weight components. Systems with PVP addition showed “stronger” behaviour according to the S approach. Polarized light, scanning electron and atomic force microscopies showed slight differences in transparency and shapes between controls and systems with PVP addition. Surface morphological changes and roughness were investigated in this study to provide insight into HP and CS particles’ structural changes. Moreover, S-involved structural diagrams were built to determine S parameters for controlling the structural transformation of HP and CS systems with and without PVP addition. The results obtained in this work provide new information on polymer-carbohydrate interactions in complex food systems and structural transformations during their production and storage
Coupled steroid and phosphorus leaching from cattle slurry at lysimeter scale
Get PDFpeer-reviewedWater quality degradation can be caused by excessive agricultural nutrient transfers from fertilised soils exposed to wet weather. Mitigation measures within the EU Nitrates Directive aim to reduce this pressure by including ‘closed’ fertiliser spreading periods during wet months. For organic fertilisers such as slurry and manure, this closed period requires sufficient on-farm winter storage and good weather conditions to relieve storage at the end of the period. Therefore, robust scientific evidence is needed to support the measure. Incidental nutrient transfers of recently applied organic fertilisers in wet weather can also be complicated by synchronous transfers from residual soil stores and tracing is required for risk assessments. The combination of nutrient monitoring and biomarker analyses may aid this and one such biomarker suite is faecal steroids. Accordingly, this study investigated the persistence of steroids and their association with phosphorus during leaching episodes. The focus was on the coupled behaviour of steroids and total phosphorus (TP) concentrations in sub-surface hydrological pathways. Cattle slurry was applied to monolith lysimeters either side of a closed period and concentrations of both steroids and TP were monitored in the leachate. The study showed no significant effect of the treatment (average p = 0.17), though tracer concentrations did significantly change over time (average p = 0.001). While the steroidal concentration ratio was validated for herbivorous faecal pollution in the leachate, there was a weak positive correlation between the steroids and TP. Further investigation at more natural scales (hillslope/catchment) is required to confirm tracer behaviours/correlations and to compliment this sub-surface pathway study
Optimising soil P levels reduces N2O emissions in grazing systems under different N fertilisation
Get PDFpeer-reviewedThe effect of long-term soil phosphorus (P) on in situ nitrous oxide (N2O) emissions from temperate grassland soil ecosystems is not well understood. Grasslands typically receive large nitrogen (N) inputs both from animal deposition and fertiliser application, with a large proportion of this N being lost to the environment. Understanding optimum nutrient stoichiometry by applying N fertilisers in a relative balance with P will help to reduce N losses by enabling maximum N-uptake by plants and microbes. This study investigates the N2O response from soils of long-term high and low P management receiving three forms of applied N at two different rates: a nitrate-based fertiliser (KNO3) and an ammonium-based fertiliser ([NH4]2SO4) (both at 40 Kg N ha−1), and a synthetic urine (750 Kg N ha−1). Low soil P significantly increased N2O emissions from KNO3 and (NH4)2SO4 fertilisers by over 50% and numerically increased N2O from urine by over 20%, which is suggested to be representative of the lack of significant effect of N fertilisation on N-uptake observed in the low P soils. There was a significant positive effect of soil P on grass N-uptake observed in the synthetic urine and KNO3 treatments, but not in the (NH4)2SO4 treatment. Low P soils had a significantly lower pH than high P soilss and responded differently to applied synthetic urine. There was also a significant effect of P level on potential nitrification which was nearly three times that of low P, but no significant difference between potential denitrification and P level. The results from this study highlight the importance of synergy between relative nutrient applications as a deficiency of one nutrient, such as P in this case, could be detrimental to the system as a whole. Optimising soil P can result in greater N uptake (over 12, 23 and 66% in (NH4)2SO4, KNO3 and synthetic urine treatments, respectively) and in reduced emissions by up to 50% representing a win-win scenario for farmers
Ewe breed differences in the cervical transcriptome at the follicular phase of a synchronised oestrous cycle
Get PDFpeer-reviewedBackground
Cervical artificial insemination (AI) with frozen-thawed semen results in unacceptably low pregnancy rates internationally. The exception is in Norway, where vaginal deposition of frozen-thawed semen to a natural oestrous routinely yields pregnancy rates in excess of 70%. Previous studies by our group has demonstrated that this is due to differences in cervical sperm transport. However, a potentially important contributory factor is that ewes are inseminated to a natural oestrous in Norway but to a synchronised oestrous across most of the rest of the world. In this study, we interrogated the gene expression of the sheep cervix of four ewe breeds with known differences in pregnancy rates following cervical AI using frozen-thawed semen under the effect of exogenous hormones to synchronise the oestrous cycle. These four ewe breeds (n = 8 to 11 ewes per breed) are from two countries: Ireland (Belclare and Suffolk; medium and low fertility, respectively) and Norway (Norwegian White Sheep (NWS) and Fur; both with high fertility compared to the Irish ewe breeds).
Results
RNA extracted from cervical biopsies collected from these breeds was analysed by RNA-sequencing and differential gene expression analysis. Using the low-fertility Suffolk breed as a reference level; 27, 1827 and 2641 genes were differentially expressed in Belclare, Fur and NWS ewes, respectively (P 1.5). Gene ontology (GO) analysis revealed that Fur and NWS had an up-regulation of enriched pathways involved in muscle contraction and development compared to Suffolk. However, there was a down-regulation of the immune response pathway in NWS compared to Suffolk. In addition, GO analysis showed similar expression patterns involved in muscle contraction, extracellular matrix (ECM) development and cell-cell junction in both Norwegian ewe breeds, which differed to the Irish ewe breeds.
Conclusions
This novel study has identified a number of conserved and breed-specific biological processes under the effect of oestrous synchronisation that may impact cervical sperm transport during the follicular phase of the reproductive cycle
Celebrating 60 years of the Irish Journal of Agricultural and Food Research
Get PDFForeword to Special IssueThis special issue consists of 12 papers, compiled in 2021 — the journal’s anniversary year, providing an overview of the wide range of research undertaken by Teagasc. These papers provide a great source of reference for those interested in Irish agricultural and food research. Topics include forestry, potato breeding and production, pig production, milk quality and processing, meat processing, ruminant nutrition, ruminant breeding, the Agricultural Catchments Programme, grassland, animal health and welfare, and the role of social science in agri food research
Gene co-expression networks contributing to variation in residual feed intake in bovine hepatic tissue
No full textGene co-expression network analyses were performed on hepatic transcriptome data of two breed types
(Charolais (CH) and Holstein-Friesian (HF)), divergent for feed efficiency status through measurement
of residual feed intake (RFI). The relationship between co-expressed genes and RFI was further assessed
through correlation of co-expression networks with trait data including RFI, average daily gain (ADG) and
dry matter intake (DMI). Across both breeds examined, one network of co-expressed genes was positively
correlated with DMI (r=0.48, P=0.03), with a tendency also identified between the same network and RFI
(r=0.42, P=0.07). Functional annotation of genes within this network revealed enrichment (P<0.05) of
pathways related to both amino acid and fatty acid metabolism. Our results suggest a role for these processes
in the hepatic tissue of cattle divergent for RFI. Moreover, genes within this network may represent potential
biomarkers for the selection of improved feed efficiency in cattle across varying breed types
Impact of early life nutrition on the molecular control of sexual development in the bull calf
No full textIntegrative network analysis on the nutrigenomic control of reproductive development in cattle
No full textAdvancements in next generation sequencing technologies have greatly increased our understanding and capability in
deciphering the complex molecular control regulating important biological traits in cattle. More recently efforts have
been focused towards evaluating ‘omics’ datasets, (genomic, transcriptomic, proteomic), in unison, through systems
biology based analytical approaches. Such integrative analyses allow for a more comprehensive evaluation of the
underlying biology governing traits of interest, determining discrete relationships between genes towards a particular
trait as opposed to merely focusing on genes with the largest difference, evident through differential expression analysis
alone. Moreover, through gene co-expression analyses, networks of highly correlated genes may be derived, with the
additional utility of identifying ‘hub genes’. Hub genes are of particular interest as such genes are key to the regulation
of additional genes within a network and thus are key to controlling the expression of a particular trait. Furthermore,
the importance of hub genes to the regulation of a particular trait may not be apparent through differential expression
analyses alone, thus highlighting the functionality of gene co-expression analyses. Additionally, through the integration
of various types of genomic data, for example, genetic and transcriptomic, the functional role of specific SNPs may be
evaluated, based on the interaction between genes harbouring SNPs and the larger co-expression network. Recently,
we have applied such integrative molecular analyses towards deciphering the effect of enhanced nutritional status
on the regulation of reproductive development in prepubertal cattle. Transcriptomic and proteomic data from tissues
of the hypothalamic-pituitary-testicular (HPT) signalling axis were integrated. In particular a putative role of the
miR-2419 miRNA towards reproductive development within the HPT tissues of bull calves was apparent through
enrichment of processes related to metabolism, GnRH signalling, and cholesterol biosynthesis across tissues of the
HPT axis. Knowledge derived from such analyses may be used to identify more accurate genomic targets within the
context of genomically assisted breeding programs