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This study aimed to 1) examine nutrient digestibility, rumen fermentation and microbial synthesis, and enteric methane emission when feeding diets high in sugar content provided as freshly stored or ensiled sugar beets to dairy cows, and 2) to evaluate the methane mitigation potential of ensiled sugar beets with different nutrient composition (sugar vs. alcohol) by use of an additive during ensiling. Four rumen, duodenal and ileal fistulated Danish Holstein dairy cows were used in a 4 × 4 Latin square design with 21-d periods. Maize silage was included in the control diet (CON) and was partially replaced in the experimental diets with either freshly stored sugar beets (SBF), ensiled beets with ensiling additive (SBE+), or ensiled beets without ensiling additive (SBE−) at 196 g/kg dietary dry matter (DM) content. Cows adapted to the diets for 11 d, after which rumen liquid and digesta were collected over 5 d, and gas exchange was measured in respiration chambers over the next 5 d. Dry matter intake (DMI), daily methane production, and methane per kg organic matter (OM) intake, rumen digested OM, and energy-corrected milk (ECM) yield were unaffected by diet. Methane per kg DMI (tendency) and per kg OM intake was lower for SBE– compared to SBF. Nutrient digestibility of DM, OM, starch, and neutral detergent fibre in different sections of the digestive tract were unaffected by diet. Molar proportion of acetate in rumen liquid decreased for ensiled sugar beet diets relative to CON, while molar proportions of propionate and acetate-to-propionate ratio remained unaffected. Molar proportion of butyrate was higher for SBE+ than CON. Microbial crude protein synthesis and microbial efficiency were unaffected by diet. Milk yield and ECM yield (tendency) were lower for SBE+ than CON. In conclusion, freshly stored sugar beets and sugar beets ensiled with or without additive, can replace maize silage in dairy cattle rations without adverse effects on DMI, rumen fermentation, and nutrient digestibility, and without altering most expressions of methane emissions, but methane per kg of OM intake was lower for beets ensiled without additive compared to freshly stored beets. The ECM yield, however, tends to be lowered for ensiled beets with additive.

The Last Interglacial (LIG) experienced substantial changes in seasonal insolation compared with the present day, which may have affected the hydrography and water-mass exchange in the North Sea and Baltic Sea region. Here we investigate the effects of solar radiation and greenhouse gas (GHG) forcing on the regional climate by analyzing model simulations of the LIG (127 ka BP), pre-industrial (PI, 1850 CE), and present-day (PD, 1990 CE) climates. We also interpret the reconstructed seasonal bottom water conditions using benthic foraminifera and geochemistry data. Our simulations reveal that during the LIG, the Baltic Sea region (including the Kattegat and the Danish Straits) experienced more saline and colder bottom waters than those in the PD, in agreement with the reconstruction data. This can be attributed to lower GHG levels and enhanced water exchange of cooler, saline North Sea water into the Baltic Sea during the LIG. The thermocline was stronger during the summer months in the LIG, mainly due to the higher sea surface temperature (SST) compared to that of the PD resulting from increased summer insolation. Further, the temperature anomalies (LIG–PD) show significant inverse correlations with the precipitation–minus–evaporation (P–E) at the Baltic Sea entrance. However, the P–E balance appears to have had minimal impact on salinity changes in the North Sea, the Baltic Proper, and the open sea area. Our findings indicate that monthly surface and bottom water salinity anomalies of LIG-PI exhibit strong positive correlations with the North Atlantic Oscillation (NAO) anomalies in the Baltic entrance region. During the LIG, a more positive phase of the NAO index in autumn played a crucial role in wind-driven major inflows and led to more intensive water exchange in the North Sea–Baltic Sea region compared to the late Holocene.

The phase transition between galaxies and quasars is often identified with the rare population of hyper-luminous, hot dust-obscured galaxies. Galaxy formation models predict these systems to grow via mergers, that can deliver large amounts of gas toward their centers, induce intense bursts of star formation and feed their supermassive black holes. Here we report the detection of 24 galaxies emitting Lyman-alpha emission on projected physical scales of about 400 kpc around the hyper-luminous hot dust-obscured galaxy W0410-0913, at redshift z = 3.631, using Very Large Telescope observations. While this indicates that W0410-0913 evolves in a very dense environment, we do not find clear signs of mergers that could sustain its growth. Data suggest that if mergers occurred, as models expect, these would involve less massive satellites, with only a moderate impact on the internal interstellar medium of W0410-0913, which is sustained by a rotationally-supported fast-rotating molecular disk, as Atacama Large Millimeter Array observations suggest., 26 pages, 12 figures, 1 table. Authors' version. Published in Nature Communications on 05 August 2022

We present Atacama Large Millimetre Array (ALMA) 2mm continuum observations of a complete and unbiased sample of 99 870micron-selected sub-millimeter galaxies (SMGs) in the Extended Chandra Deep Field South (ALESS). Our observations of each SMG reach average sensitivities of 53 microJy/beam. We measure the flux densities for 70 sources, for which we obtain a typical 870micron-to-2mm flux ratio of 14 +/- 5. We do not find a redshift dependence of this flux ratio, which would be expected if the dust emission properties of our SMGs were the same at all redshifts. By combining our ALMA measurements with existing Herschel/SPIRE observations, we construct a (biased) subset of 27 galaxies for which the cool dust emission is sufficiently well sampled to obtain precise constraints on their dust properties using simple isothermal models. Thanks to our new 2mm observations, the dust emissivity index is well-constrained and robust against different dust opacity assumptions. The median dust emissivity index of our SMGs is $\beta\simeq1.9\pm0.4$, consistent with the emissivity index of dust in the Milky Way and other local and high-redshift galaxies, as well as classical dust grain model predictions. We also find a negative correlation between the dust temperature and $\beta$, similar to low-redshift observational and theoretical studies. Our results indicate that $\beta\simeq2$ in high-redshift dusty star-forming galaxies, implying little evolution in dust grain properties between our SMGs and local dusty galaxy samples, and suggesting these high-mass and high-metallicity galaxies have dust reservoirs driven by grain growth in their ISM., Comment: 31 pages, 20 figures, accepted for publication in the Astrophysical Journal

International audience; The objective of Feed-a-Gene (H2020 grant agreement 633531) was to adapt the feed, the animal and the feeding techniques to improve the efficiency and sustainability of monogastric livestock production systems. Efficiency is a complex trait affecting the components of sustainability. Imported soybean meal is a high-quality protein source, but its use can have environmental and social impacts. Technological treatments applied to European-grown protein sources (i.e. soybean meal, rapeseed meal, and green biomass) allow to obtain fractions with different nutritional characteristics that can be fed to different livestock species. Replacing Brazilian soybean meal with locally-produced protein sources reduced energy cost and impact on climate change, but resulted in a transfer of land-use and in more arable land use. Novel traits indicative for feed efficiency were developed and tested (e.g. individual feed intake in broilers, genomic information on nitrogen efficiency, large-scale measurements of digestibility in individual pigs, blood metabolites, and behavioural traits). These traits can be used in livestock management strategies, and digestibility, microbiota, and blood biomarkers appeared promising for genetic selection. Different mathematic models were developed to assess digestive and metabolic efficiency, animal robustness, and variation among animals. A userfriendly tool was developed allowing users to work with these models. Prototypes of precision feeding systems were developed for broilers, growing pigs, and sows. These systems adjust the type of feed to the daily changing nutritional requirements of individual or groups of animals. Precision feeding in pigs reduced key environmental impacts and increased profitability compared to conventional feeding systems.

Owing to the lack of absolutely dated oceanographic information before the modern instrumental period, there is currently significant debate as to the role played by North Atlantic Ocean dynamics in previous climate transitions (for example, Medieval Climate Anomaly-Little Ice Age, MCA-LIA). Here we present analyses of a millennial-length, annually resolved and absolutely dated marine δ18O archive. We interpret our record of oxygen isotope ratios from the shells of the long-lived marine bivalve Arctica islandica (δ18O-shell), from the North Icelandic shelf, in relation to seawater density variability and demonstrate that solar and volcanic forcing coupled with ocean circulation dynamics are key drivers of climate variability over the last millennium. During the pre-industrial period (AD 1000–1800) variability in the sub-polar North Atlantic leads changes in Northern Hemisphere surface air temperatures at multi-decadal timescales, indicating that North Atlantic Ocean dynamics played an active role in modulating the response of the atmosphere to solar and volcanic forcing., We thank the members of the RV Bjarni Saemundsson (Cruise No. B05-2006). This work was supported by the NERC-funded ULTRA project (Grant Number NE/H023356/1), NERC-funded CLAM project; (Project No. NE/N001176/1) and EU Millennium Project (Project number 017008). This study is a contribution to the Climate Change Consortium for Wales (C3W). We thank Brian Long (Bangor University) and Dr Julia Becker (Cardiff University) for their technical support, and Dr Manfred Mudelsee for his assistance with the trend analysis. We thank Dr Jessica Tierney and an anonymous reviewer for providing the constructive comments in the reviewing process.