Objectives, Purpose, Or Aim: The aim of this article is to contribute to the better design of wayfinding systems by explicating the indexical properties of directional arrows and their consequences for wayfinding behavior.
Background: The challenges associated with designing for the wayfinding needs of the different groups of users continue to be documented with the poor design of built environments being largely to blame for the wayfinders' inability to navigate complex settings. Directional arrows have been found to be especially problematic in such settings.
A network analysis including relative abundances of all ruminal microbial genera (archaea, bacteria, fungi, and protists) and their genes was performed to improve our understanding of how the interactions within the ruminal microbiome affects methane emissions (CH). Metagenomics and CH data were available from 63 bovines of a two-breed rotational cross, offered two basal diets. Co-abundance network analysis revealed 10 clusters of functional niches.
View Article and Find Full Text PDFFollowing publication of the original article [1], the authors reported an error in the Additional file 1.
View Article and Find Full Text PDFIncreasing the lipid concentration and/or inclusion of nitrate in the diet of ruminant livestock have been proposed as effective strategies to reduce the contribution of methane from the agricultural sector to greenhouse gas emissions. In this study, the effects of increased lipid or added nitrate on beef eating quality were investigated in two experiments. In experiment 1, lipid and nitrate were fed alone with two different and contrasting basal diets to finishing beef cattle.
View Article and Find Full Text PDFPrevious shotgun metagenomic analyses of ruminal digesta identified some microbial information that might be useful as biomarkers to select cattle that emit less methane (CH), which is a potent greenhouse gas. It is known that methane production (g/kgDMI) and to an extent the microbial community is heritable and therefore biomarkers can offer a method of selecting cattle for low methane emitting phenotypes. In this study a wider range of cattle, varying in breed and diet, was investigated to determine microbial communities and genetic markers associated with high/low CH emissions.
View Article and Find Full Text PDFBackground: The emergence and spread of antimicrobial resistance is the most urgent current threat to human and animal health. An improved understanding of the abundance of antimicrobial resistance genes and genes associated with microbial colonisation and pathogenicity in the animal gut will have a major role in reducing the contribution of animal production to this problem. Here, the influence of diet on the ruminal resistome and abundance of pathogenicity genes was assessed in ruminal digesta samples taken from 50 antibiotic-free beef cattle, comprising four cattle breeds receiving two diets containing different proportions of concentrate.
View Article and Find Full Text PDFThe aim of this study was to assess individual differences in temperament and stress response and quantify their impact on feed efficiency, performance, and methane (CH4) emissions in beef cattle. Eighty-four steers (castrated males) (Charolais or Luing) were used. Temperament was assessed using two standardized tests: restlessness when restrained [crush score (CS)] and flight speed (FS) on release from restraint.
View Article and Find Full Text PDFRuminal methane production is among the main targets for greenhouse gas (GHG) mitigation for the animal agriculture industry. Many compounds have been evaluated for their efficacy to suppress enteric methane production by ruminal microorganisms. Of these, nitrate as an alternative hydrogen sink has been among the most promising, but it suffers from variability in efficacy for reasons that are not understood.
View Article and Find Full Text PDFMethane produced by methanogenic archaea in ruminants contributes significantly to anthropogenic greenhouse gas emissions. The host genetic link controlling microbial methane production is unknown and appropriate genetic selection strategies are not developed. We used sire progeny group differences to estimate the host genetic influence on rumen microbial methane production in a factorial experiment consisting of crossbred breed types and diets.
View Article and Find Full Text PDFBackground: Methane represents 16 % of total anthropogenic greenhouse gas emissions. It has been estimated that ruminant livestock produce ca. 29 % of this methane.
View Article and Find Full Text PDFAim: To introduce nurse and healthcare researchers to the ethnomethodological (EM) criteria of the unique adequacy (UA) requirement of methods and to provide guidance on conducting UA research.
Background: Despite the recent shift in emphasis from quantitative to qualitative methods in nursing research, the practice of EM has been largely overlooked.
Data Sources: Published work in EM.
Methane produced from 35 Aberdeen-Angus and 33 Limousin cross steers was measured in respiration chambers. Each group was split to receive either a medium- or high-concentrate diet. Ruminal digesta samples were subsequently removed to investigate correlations between methane emissions and the rumen microbial community, as measured by qPCR of 16S or 18S rRNA genes.
View Article and Find Full Text PDFThe aims of the present study were to quantify hydrogen (H2) and methane (CH4) emissions from beef cattle under different dietary conditions and to assess how cattle genotype and rumen microbial community affected these emissions. A total of thirty-six Aberdeen Angus-sired (AAx) and thirty-six Limousin-sired (LIMx) steers were fed two diets with forage:concentrate ratios (DM basis) of either 8:92 (concentrate) or 52:48 (mixed). Each diet was fed to eighteen animals of each genotype.
View Article and Find Full Text PDFProblem: The type I interferon (IFN), IFN-tau (τ), is the primary embryonic signal for pregnancy maintenance in ruminants. This study determined the effects of heat shock upon IFN-τ (IFNT) gene expression by bovine blastocysts in vitro.
Method Of Study: In vitro-produced blastocyst-stage embryos were exposed to 42°C for 4 hr, and mRNA for heat-shock protein 70 (HSP70) and IFNT quantified.
Scottish Blackface ewes from cobalt-deficient farmland were fed a diet containing 0.06 mg cobalt per kg dry matter from approximately 30 days before embryo recovery/transfer until lambing. Ewes remained untreated (-Co; n = 82) or were given an intraruminal cobalt-containing bolus to compensate for the dietary deficit (+Co; n = 82).
View Article and Find Full Text PDFProblem: Uterine-derived factors are required for optimal conceptus development and secretion of the maternal recognition of pregnancy factor, interferon-tau (IFN-tau). Identifying these factors may lead to the development of schemes for increasing pregnancy success in cattle.
Method Of Study: The objectives were to examine the effects of granulocyte-macrophage colony-stimulating-factor (GM-CSF) on trophectoderm proliferation rates and IFN-tau production, and verify the appropriateness of using an in vitro model of bovine trophectoderm (CT-1 cell).
In each of three experiments, in vitro-matured and -fertilised zygotes were cultured to Day 7 post insemination in synthetic oviductal fluid (SOF). In Experiment 1, zygotes were cultured in groups in either SOF plus albumin (SOFA) or serum (SOFS) and then blastocysts were cultured individually for a further 24 h without a change of media. In Experiment 2, zygotes were cultured in groups using a 2 x 2 factorial design in SOFA or SOFS, with or without recombinant ovine granulocyte-macrophage colony stimulating factor (GM-CSF; 5 ng mL(-1)).
View Article and Find Full Text PDFThe effects of applying either formic acid (5.4 g kg ), a mixture of formic acid (2.7 g kg ) and formaldehyde (1.
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