386 research outputs found

    The effect of kale cultivar and sowing date on dry matter intake, crop utilization, liveweight gain and body condition score gain of pregnant, non-lactating dry dairy cows in winter in New Zealand

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    An outdoor grazing study on kale was conducted with pregnant, nonlactating (dry) dairy cows over a 42-day winter grazing period commencing 9 June 2008. Kale treatments consisted of two kale cultivars varying in leaf:stem proportion ("Regal," a leafy variety and "Caledonian," a stemmy variety) and two sowing dates (8 November and 15 December). Measurements were made for dry-matter (DM) utilization, apparent DM intake, liveweight gain and changes in body condition score (BCS) for a total of 120 cows allocated to three replicate groups of the four factorial treatments. Cows were offered a daily allowance of 10 kg DM/cow of kale and 2.2 kg DM/cow of straw. Pregrazing DM yield was higher for kale sown in November (16,517 kg DM/ha) than December (13,867 kg DM/ha), but was unaffected by cultivar (average 15,192 kg DM/ha). "Regal" kale had a higher percentage of leaf compared with "Caledonian" (33.6% vs. 25.6%), lower content of NDF (32.4% vs. 34.1%), but similar metabolizable energy content (12.1 MJ/kg DM for both) in the whole plant. Despite the differences in pregrazing DM yield and forage quality among treatments, no differences were found in DM utilization (between 88.5% and 90.2%), apparent DM intake (between 9.4 and 9.6 kg DM/cow.day), liveweight gain (between 0.53 and 0.67 kg/cow.day) and BCS gain (between 0.43 and 0.46 unit/cow over 42 days). Manipulation of kale yield and quality through choice of cultivar and sowing date had no effect on the performance of pregnant, nonlactating dairy cows

    Scientific Opinion on safety and efficacy of coated granulated cobaltous carbonate monohydrate as feed additive for all species

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    <p>Cobalt(III) is a component of cobalamin. Its essentiality as trace element results from the capacity of certain animal species to synthesise cobalamin by the gastrointestinal microbiota. Feeding cobalt(II) carbonate hydroxide (2:3) monohydrate up to the maximum authorised total cobalt in feed is safe for the target animals. Cobalt is predominantly excreted via the faecal route. Absorbed cobalt follows aqueous excretion routes. About 43 % of body cobalt is stored in muscle; however, kidney and liver are the edible tissues containing the highest cobalt concentrations and are most susceptible to reflect dietary cobalt concentrations. In animals with the capacity to synthesise cobalamin, cobalt is also deposited in tissues as vitamin B<sub>12</sub>. Cobalt(II) cations are genotoxic under <em>in vitro</em> and <em>in vivo</em> conditions. Cobalt(II) carbonate has carcinogen, mutagen and reproduction toxicant (CMR) properties. No data are available on the potential carcinogenicity of cobalt(II) following oral exposure. However, oral exposure may potentially entail adverse threshold-related effects in humans. The estimated population intake of cobalt most likely includes the contribution of foodstuffs from animals fed cobalt-supplemented feedingstuffs. An increase in cobalt exposure by the use of cobalt-containing feed additives is therefore not expected. Considering the population exposure to cobalt, about 4ā€“10 times lower than the health-based guidance value, no safety concern for the consumer is expected for threshold effects of oral cobalt. Cobalt(II) carbonate is a skin and eye irritant, and a dermal and respiratory sensitiser. Its dust is a hazard to persons handling the substance. Exposure by inhalation must be avoided. The use of cobalt from any source at the authorised maximum content in feed does not provide a risk to the environment. The coated granulated cobalt(II) carbonate hydroxide (2:3) monohydrate is available for cobalamin synthesis in the rumen and therefore effective in ruminants; this conclusion is extrapolated to horses and rabbits.</p&gt

    Combining two nationalā€scale datasets to map soil properties, the case of available magnesium in England and Wales

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    Given the costs of soil survey it is necessary to make the best use of available datasets, but data that differ with respect to some aspect of the sampling or analytical protocol cannot be combined simply. In this paper we consider a case where two datasets were available on the concentration of plantā€available magnesium in the topsoil. The datasets were the Representative Soil Sampling Scheme (RSSS) and the National Soil Inventory (NSI) of England and Wales. The variable was measured over the same depth interval and with the same laboratory method, but the sample supports were different and so the datasets differ in their variance. We used a multivariate geostatistical model, the linear model of coregionalization (LMCR), to model the joint spatial distribution of the two datasets. The model allowed us to elucidate the effects of the sample support on the two datasets, and to show that there was a strong correlation between the underlying variables. The LMCR allowed us to make spatial predictions of the variable on the RSSS support by cokriging the RSSS data with the NSI data. We used crossā€validation to test the validity of the LMCR and showed how incorporating the NSI data restricted the range of prediction error variances relative to univariate ordinary kriging predictions from the RSSS data alone. The standardized squared prediction errors were computed and the coverage of prediction intervals (i.e. the proportion of sites at which the prediction interval included the observed value of the variable). Both these statistics suggested that the prediction error variances were consistent for the cokriging predictions but not for the ordinary kriging predictions from the simple combination of the RSSS and NSI data, which might be proposed on the basis of their very similar mean values. The LMCR is therefore proposed as a general tool for the combined analysis of different datasets on soil properties

    Rural Development Programme measures on cultivated land in Europe to mitigate greenhouse gas emissions ā€“ regional ā€˜hotspotsā€™ and priority measures

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    Ā© 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.Agriculture is a significant source of GHG emissions, contributing 10% of total emissions within the EU-28. Emissions from European agriculture have been reduced, albeit at the expense of crop yield and the risk of production displacement (the transfer of production, and associated emissions, to land outside of Europe). This article assesses the impact on GHG emissions of selected European Rural Development Program measures, representative of a diversity of management strategies implemented on cultivated land, within nine European Member States. Climatic zone and underlying spatial environmental variables were accounted for using a novel technique, ā€œRegional Variation Categories,ā€ developed with European-scale GIS data sets. Production displacement is assessed with two benchmarks: (1) compared with existing crop production and (2) relative to a ā€œminimum requirementā€ land management scenario, where an emissions reduction of less than this does not constitute mitigation. Most measures reduce emissions relative to the baseline crop scenario; however, many do not reduce emissions beyond the ā€œminimum requirement,ā€ this being limited to measures such as catch crops and within-field grass areas to prevent soil erosion. The selection and targeting of measures to maximize agricultural GHG mitigation on cultivated land within Europe is discussed...Peer reviewedFinal Published versio

    Added dietary sulfur and molybdenum has a greater influence on hepatic copper concentration, intake, and performance in Holstein-Friesian dairy cows offered a grass silage- rather than corn silage-based diet

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    To test the hypothesis that the metabolism of Cu in dairy cows is affected by basal forage and added S and Mo, 56 dairy cows that were 35 (standard error Ā± 2.2) days postcalving and yielding 38.9 kg of milk/d (standard error Ā± 0.91) were offered 1 of 4 diets in a 2 Ɨ 2 factorial design for a 14-wk period. The 4 diets contained approximately 20 mg of Cu/kg of dry matter (DM), and had a corn silage-to-grass silage ratio of 0.75:0.25 (C) or 0.25:0.75 (G) and were either unsupplemented (āˆ’) or supplemented (+) with an additional 2 g of S/kg of DM and 6.5 mg of Mo/kg of DM. We found an interaction between forage source and added S and Mo on DM intake, with cows offered G+ having a 2.1 kg of DM lower intake than those offered Gāˆ’, but no effect on the corn silage-based diets. Mean milk yield was 38.9 kg/d and we observed an interaction between basal forage and added S and Mo, with yield being decreased in cows offered G+ but increased on C+. No effect of dietary treatment on milk composition or live weight was noted, but body condition was lower in cows fed added S and Mo irrespective of forage source. We found an interaction between forage source and added S and Mo on milk somatic cell count, which was higher in cows offered G+ compared with Gāˆ’, but not in cows fed the corn silage-based diets, although all values were low (mean values of 1.72, 1.50, 1.39, and 1.67 log10/mL for Cāˆ’, C+, Gāˆ’, and G+, respectively). Mean plasma Cu, Fe, and Mn concentrations were 13.8, 41.3, and 0.25 Āµmol/L, respectively, and were not affected by dietary treatment, whereas plasma Mo was 0.2 Āµmol/L higher in cows receiving added S and Mo. The addition of dietary S and Mo decreased liver Cu balance over the study period in cows fed either basal forage, but the decrease was considerably greater in cows receiving the grass silage-based diet. Similarly, hepatic Fe decreased more in cows receiving G than C when S and Mo were included in the diet. We concluded that added S and Mo reduces hepatic Cu reserves irrespective of basal forage source, but this decrease is considerably more pronounced in cows receiving grass silage- than corn silage-based rations and is associated with a decrease in intake and milk performance and an increase in milk somatic cell count

    A method for single pair mating in an obligate parasitic nematode

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    Parasitic nematode species have extremely high levels of genetic diversity, presenting a number of experimental challenges for genomic and genetic work. Consequently, there is a need to develop inbred laboratory strains with reduced levels of polymorphism. The most efficient approach to inbred line development is single pair mating, but this is challenging for obligate parasites where the adult sexual reproductive stages are inside the host, and thus difficult to experimentally manipulate. This paper describes a successful approach to single pair mating of a parasitic nematode, Haemonchus contortus. The method allows for polyandrous mating behaviour and involves the surgical transplantation of a single adult male worm with multiple immature adult females directly into the sheep abomasum. We used a panel of microsatellite markers to monitor and validate the single pair mating crosses and to ensure that the genotypes of progeny and subsequent filial generations were consistent with those expected from a mating between a single female parent of known genotype and a single male parent of unknown genotype. We have established two inbred lines that both show a significant overall reduction in genetic diversity based on microsatellite genotyping and genome-wide single nucleotide polymorphism. There was an approximately 50% reduction in heterozygous SNP sites across the genome in the MHco3.N1 line compared with the MoHco3(ISE) parental strain. The MHco3.N1 inbred line has subsequently been used to provide DNA template for whole genome sequencing of H. contortus. This work provides proof of concept and methodologies for forward genetic analysis of obligate parasitic nematodes

    Cross-Sector Review of Drivers and Available 3Rs Approaches for Acute Systemic Toxicity Testing

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    Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area

    Changing leaf nitrogen and canopy height quantify processes leading to plant and butterfly diversity loss in agricultural landscapes

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    1. We describe a novel method for quantifying ecosystem drivers that potentially compromise the effectiveness of agri-environment schemes. We use three sources of data that for many countries are already in the public domain: governmental agricultural statistics, which provide a quantitative assessment of farming intensity in the working landscape', data on threat status and species distribution for plants and butterflies from conservation agencies and similar bodies and functional traits of plant species abstracted from published data bases. 2. Changes in land use alter ecosystem processes which in turn modify both biodiversity and representation of functional types at the landscape scale. We interpret functional shifts to quantify important ecological drivers of floristic and faunal change and their causal land use origins. 3. We illustrate the power of this approach by means of a worked example. We demonstrate that despite conservation policies to counteract them, eutrophication, identified by leaf nitrogen content, and abandonment, correlated with plant canopy height, are still causing biodiversity loss to native higher plants and butterflies in the English countryside. 4. We use our analyses to suggest how conservation policies can be made more effective and discuss how similar approaches could be applied elsewhere
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