Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Conifer and broadleaved trees differ in branch allometry but maintain similar functional balances
    Zhang, Lan ; Chen, Yajun ; Hao, Guangyou ; Ma, Keping ; Bongers, Frans ; Sterck, Frank J. - \ 2020
    Tree Physiology 40 (2020)4. - ISSN 0829-318X - p. 511 - 519.
    allometry - canopy - functional balance - wood anatomy - xylem growth

    Conifers and broadleaved trees coexist in temperate forests and are expected to differ in partitioning strategies between leaf and stem. We compare functional balances between water loss and water supply, and between sugar production and sugar transport/storage, and associate these with xylem growth to better understand how they contribute to these life form strategies. We sampled canopy branches from 14 common species in a temperate forest in northeast China and measured xylem area, phloem area, ray area, ray percentage, dry wood density, xylem conductivity and mean xylem growth rate for branch stems, and the leaf area and specific leaf area for leaves, and calculated the leaf-specific conductivity. Conifers and broadleaved trees did not differ significantly in tissue areas, xylem growth rate and the relation between phloem area and leaf area. Conifers had higher xylem area but lower ray area relative to leaf area. For the same xylem conductivity, phloem area and ray parenchyma area did not differ between conifers and broadleaved trees. Xylem growth rate was similar relative to leaf area and phloem area. Our results indicate that conifers tend to develop more xylem area per leaf area and more tracheid area at the cost of ray parenchyma area, probably to compensate for the low water transport ability of tracheid-based xylem. The divergent strategies between conifers and broadleaved tree species in leaf area and xylem area partitioning probably lead to the convergence of partitioning between leaf area and phloem area. Consequently, conifers tend to consume rather than store carbon to achieve a similar xylem expansion per year as coexisting broadleaved trees.

    Physical exercise prepartum to support metabolic adaptation in the transition period of dairy cattle : A proof of concept
    Goselink, Roselinde M.A. ; Schonewille, Jan Thomas ; Duinkerken, Gert van; Hendriks, Wouter H. - \ 2020
    Journal of Animal Physiology and Animal Nutrition 104 (2020)3. - ISSN 0931-2439 - p. 790 - 801.
    body condition - calving - dairy cow - energy metabolism - exercise physiology - fat metabolism - hepatic lipidosis - lipoprotein

    In dairy cattle, the hormonal changes around calving induce large metabolic changes to support milk production. Mobilization of adipose reserves is one of the changes involved, imposing a metabolic load on the liver. We hypothesized that the risk for excessive lipolysis and hepatic lipidosis postpartum can be reduced by starting fat mobilization and processing during the prepartum period by physical exercise, especially in cows with a high body condition score (BCS). As a proof of concept, 32 pregnant Holstein-Friesian dairy cows were selected for a 2 × 2 experimental design. Sixteen cows had a BCS < 3.25 (group LOW) and 16 cows a BCS ≥ 3.25 (group HIGH). Cows within each group were randomly allocated to one of two treatments: group STEP was walked twice daily for 45 min during the dry period while group CON remained indoors. Treatment was stopped at calving and cows were monitored until 6 weeks after calving. Liver biopsies were taken in a subset of 16 cows to determine liver triglyceride (TG) concentration. We found that calculated energy balance was more negative for group STEP prepartum, resulting in higher plasma non-esterified fatty acids and β-hydroxybutyrate concentrations. During the first 6 weeks postpartum, neither dry matter intake nor milk yield was affected by exercise. As expected, the cows in group HIGH had increased liver TG concentrations postpartum relative to group LOW with increased plasma non-esterified fatty acids directly after calving. Exercise during the dry period mitigated postpartal liver TG accumulation, but this did not seem to be related to increased plasma lipoprotein transport. We conclude that substantial physical activity prepartum can induce lipolysis and lipid utilization, thereby starting an early adaptation to lactation. This may be instrumental to reduce the risk for excessive liver TG accumulation postpartum, especially in cows with a high BCS at dry-off.

    Gendered species preferences link tree diversity and carbon stocks in Cacao agroforest in Southeast Sulawesi, Indonesia
    Sari, Rika Ratna ; Saputra, Danny Dwi ; Hairiah, Kurniatun ; Rozendaal, Danaë M.A. ; Roshetko, James M. ; Noordwijk, Meine Van - \ 2020
    Land 9 (2020)4. - ISSN 2073-445X
    Cacao agroforestry - Carbon storage - Farmer tree preference - Utility value

    The degree to which the maintenance of carbon (C) stocks and tree diversity can be jointly achieved in production landscapes is debated. C stocks in forests are decreased by logging before tree diversity is affected, while C stocks in monoculture tree plantations increase, but diversity does not. Agroforestry can break this hysteresis pattern, relevant for policies in search of synergy. We compared total C stocks and tree diversity among degraded forest, complex cacao/fruit tree agroforests, simple shade-tree cacao agroforestry, monoculture cacao, and annual crops in the Konawe District, Southeast Sulawesi, Indonesia. We evaluated farmer tree preferences and the utility value of the system for 40 farmers (male and female). The highest tree diversity (Shannon-Wiener H index 2.36) and C stocks (282 Mg C ha-1) were found in degraded forest, followed by cacao-based agroforestry systems (H index ranged from 0.58-0.93 with C stocks of 75-89 Mg ha-1). Male farmers selected timber and fruit tree species with economic benefits as shade trees, while female farmers preferred production for household needs (fruit trees and vegetables). Carbon stocks and tree diversity were positively related (R2 = 0.72). Adding data from across Indonesia (n = 102), agroforestry systems had an intermediate position between forest decline and reforestation responses. Maintaining agroforestry in the landscape allows aboveground C stocks up to 50 Mg ha-1 and reduces biodiversity loss. Agroforestry facilitates climate change mitigation and biodiversity goals to be addressed simultaneously in sustainable production landscapes.

    Global Change Can Make Coastal Eutrophication Control in China More Difficult
    Wang, Mengru ; Kroeze, Carolien ; Strokal, Maryna ; Vliet, Michelle T.H. van; Ma, Lin - \ 2020
    Earth's Future 8 (2020)4. - ISSN 2328-4277
    Climate change - Coastal eutrophication - Nutrient export - Socio-economic change - Source attribution - Sub-basins

    Fast socio-economic development in agriculture and urbanization resulted in increasing nutrient export by rivers, causing coastal eutrophication in China. In addition, climate change may affect hydrology, and as a result, nutrient flows from land to sea. This study aims at a better understanding of how future socio-economic and climatic changes may affect coastal eutrophication in China. We modeled river export of total dissolved nitrogen (TDN) and phosphorus (TDP) in 2050 for six scenarios combining socio-economic pathways (SSPs) and Representative Concentration Pathways (RCPs). We used the newly developed MARINA 2.0 (Model to Assess River Inputs of Nutrients to seAs) model. We found that global change can make coastal eutrophication control in China more difficult. In 2050 coastal waters may be considerably more polluted or considerably cleaner than today depending on the SSP-RCP scenarios. By 2050, river export of TDN and TDP is 52% and 56% higher than in 2012, respectively, in SSP3-RCP8.5 (assuming large challenges for sustainable socio-economic development, and severe climate change). In contrast, river export of nutrients could be 56% (TDN) and 85% (TDP) lower in 2050 than in 2012 in SSP1-RCP2.6 (assuming sustainable socio-economic development, and low climate change). Climate change alone may increase river export of nutrients considerably through hydrology: We calculate 24% higher river export of TDN and 16% higher TDP for the SSP2 scenario assuming severe climate change compared to the same scenario with low climate change (SSP2-RCP8.5 vs. SSP2-RCP2.6). Policies and relevant technologies combining improved nutrient management and climate mitigation may help to improve water quality in rivers and coastal waters of China.

    A comparison of high-throughput plasma NMR protocols for comparative untargeted metabolomics
    Bliziotis, Nikolaos G. ; Engelke, Udo F.H. ; Aspers, Ruud L.E.G. ; Engel, Jasper ; Deinum, Jaap ; Timmers, Henri J.L.M. ; Wevers, Ron A. ; Kluijtmans, Leo A.J. - \ 2020
    Metabolomics 16 (2020)5. - ISSN 1573-3882
    Classification - High-throughput - Large scale - LED - Metabolomics - NMR

    Introduction: When analyzing the human plasma metabolome with Nuclear Magnetic Resonance (NMR) spectroscopy, the Carr–Purcell–Meiboom–Gill (CPMG) experiment is commonly employed for large studies. However, this process can lead to compromised statistical analyses due to residual macromolecule signals. In addition, the utilization of Trimethylsilylpropanoic acid (TSP) as an internal standard often leads to quantification issues, and binning, as a spectral summarization step, can result in features not clearly assignable to metabolites. Objectives: Our aim was to establish a new complete protocol for large plasma cohorts collected with the purpose of describing the comparative metabolic profile of groups of samples. Methods: We compared the conventional CPMG approach to a novel procedure that involves diffusion NMR, using the Longitudinal Eddy-Current Delay (LED) experiment, maleic acid (MA) as the quantification reference and peak picking for spectral reduction. This comparison was carried out using the ultrafiltration method as a gold standard in a simple sample classification experiment, with Partial Least Squares–Discriminant Analysis (PLS-DA) and the resulting metabolic signatures for multivariate data analysis. In addition, the quantification capabilities of the method were evaluated. Results: We found that the LED method applied was able to detect more metabolites than CPMG and suppress macromolecule signals more efficiently. The complete protocol was able to yield PLS-DA models with enhanced classification accuracy as well as a more reliable set of important features than the conventional CPMG approach. Assessment of the quantitative capabilities of the method resulted in good linearity, recovery and agreement with an established amino acid assay for the majority of the metabolites tested. Regarding repeatability, ~ 85% of all peaks had an adequately low coefficient of variation (< 30%) in replicate samples. Conclusion: Overall, our comparison yielded a high-throughput untargeted plasma NMR protocol for optimized data acquisition and processing that is expected to be a valuable contribution in the field of metabolic biomarker discovery.

    Quantitative mapping of lignin : Comprehensive insight into fungal delignification of plant biomass
    Erven, Gijs van - \ 2020
    Wageningen University. Promotor(en): W.J.H. van Berkel, co-promotor(en): M.A. Kabel. - Wageningen : Wageningen University - ISBN 9789463953658 - 259

    Plant biomass delignification is crucial for terrestrial carbon cycling and is essential for incentives aiming at the valorization of lignocellulose. For understanding this central process in nature and biorefinery, we need to elucidate and comprehend the mechanisms that govern recalcitrance and conversion at the molecular level. This insight can only be obtained by accurate analysis of the molecules involved, both contentwise and structurewise. This research, therefore, aimed to advance the quantitative mapping of lignin and employ the developed analytical toolkit to unravel the underlying mechanisms of a process that has largely remained elusive to date: the fungal delignification of plant biomass.

    We demonstrate through careful method validation that py-GC-MS analysis can be used for the concurrent quantification and structural characterization of grass, hardwood and softwood lignin, when employing uniformly 13C labeled lignin internal standards and relative response factors for the individual pyrolysis products.

    The developed method was used to assess three white-rot fungal species in terms of delignification effectivity and selectivity. In both important traits, Ceriporiopsis subvermispora outperformed Lentinula edodes and Pleurotus eryngii.

    Comprehensive structural analyses of the residual lignin after growth of C. subvermispora allowed us to reconstruct various degradation routes of lignin’s most abundant β-O-4’ ethers and determine the relative susceptibility of various β-O-4’ substructures. Our results imply that one-electron oxidation initiates in situ ligninolysis, which then cascades into the cleavage of Ca-Cb, Cb-O and O-4’-aryl bonds. Ligninolysis was shown to depend on the electron density of the 4’--subunit, diastereochemistry and γ-acylation.

    In addition to white-rot basidiomycete fungi, we studied the ligninolytic capacity of the ascomycete fungus P. anserina. Substrate characterization unambiguously confirmed lignin degradation and secretome analysis suggested that laccases and H2O2 producing enzymes were likely involved in the observed ligninolysis.

    Endocrine activities of phthalate alternatives; Assessing the safety profile of furan dicarboxylic acid esters using a panel of human cell based reporter gene assays
    Vugt-Lussenburg, Barbara M.A. Van; Es, Daan S. Van; Naderman, Matthijs ; Notre, Jerome Le; Klis, Frits Van Der; Brouwer, Abraham ; Burg, Bart Van Der - \ 2020
    Green Chemistry 22 (2020)6. - ISSN 1463-9262 - p. 1873 - 1883.

    FDCA esters are highly relevant biobased alternatives for currently used benzene dicarboxylic acid esters. Despite all the developments on 2,5-FDCA applications, to the best of our knowledge thus far no toxicological data were available for 2,5-FDCA esters. In the present study we aimed to fill this gap, by using an in vitro reporter gene assay approach to compare the activity profile of commonly used phthalates to that of their furan-based counterparts. The assay selection was aimed at the detection of endocrine activity, since several phthalates are heavily scrutinised for their endocrine disrupting properties. However, to avoid missing other relevant toxicological endpoints, several assays able to detect various forms of cellular stress were also included in the panel. The results showed that the (ortho)benzene dicarboxylic acid esters were predominantly active on several of the endocrine assays. In comparison, six of the seven furan dicarboxylic acid based diesters tested here showed no activity in any of the 13 assays used. Only the isobutyl derivative DIBF showed moderate estrogenic activity on one assay, compared to much more pronounced activities on four assays for the ortho-phthalate analogue. Overall, the results presented in this paper are a strong indication that 2,5-FDCA based diesters in general are not only technically viable alternatives to phthalates, but also offer significant toxicological benefits, which supports a non-regrettable substitution.

    Comparison of conditioned Latin hypercube and feature space coverage sampling for predicting soil classes using simulation from soil maps
    Ma, Tianwu ; Brus, Dick J. ; Zhu, Xing A. ; Zhang, Lei ; Scholten, Thomas - \ 2020
    Geoderma 370 (2020). - ISSN 0016-7061
    Calibration sampling - K-means - Random forest - Similarity-based predictive soil mapping - Simulated annealing - Soil sampling

    This study investigates sampling design for mapping soil classes based on multiple environmental features associated with the soil classes. Two types of sampling design for calibrating the prediction models are compared: conditioned Latin hypercube sampling (CLHS) and feature space coverage sampling (FSCS). Simple random sampling (SRS), which does not utilize the environmental features, is added as a reference design. The sample sizes used are 20, 30, 40, 50, 75, and 100 points, and at each sample size 100 sample sets were drawn using each of the three types of design. Each of these sample sets was then used to calibrate three prediction models: random forest (RF), individual predictive soil mapping (iPSM), and multinomial logistic regression (MLR). These sampling designs were compared based on the overall accuracy of predicted soil class maps obtained by these three prediction methods. The comparison was conducted in two study areas: Ammertal (Germany) and Raffelson (USA). For each of these two areas a detailed legacy soil class map is available. These soil class maps were used as references in a simulation study for the comparison. Results of both study areas show that on average FSCS outperforms CLHS and SRS for all three prediction methods. The difference in estimated medians of overall accuracy with CLHS and SRS was marginal. Moreover, the variation in overall accuracy among sample sets of the same size was considerably smaller for FSCS than that for CLHS. These results in the two study areas suggest that FSCS is a more effective sampling design.

    Acidification of manure reduces gaseous emissions and nutrient losses from subsequent composting process
    Cao, Yubo ; Wang, Xuan ; Liu, Ling ; Velthof, Gerard L. ; Misselbrook, Tom ; Bai, Zhaohai ; Ma, Lin - \ 2020
    Journal of Environmental Management 264 (2020). - ISSN 0301-4797
    Composting - GHG emissions - Manure acidification - N balance - NH emission - P balance

    Manure acidification is recommended to minimize ammonia (NH3) emission at storage. However, the potential for acidification to mitigate NH3 emission from storage and the impact of manure acidification (pH range 5–8) on composting have been poorly studied. The effects of manure acidification at storage on the subsequent composting process, nutrient balance, gaseous emissions and product quality were assessed through an analysis of literature data and an experiment under controlled conditions. Results of the data mining showed that mineral acids, acidic salts and organic acids significantly reduced NH3 emission, however, a weaker effect was observed for organic acids. A subsequent composting experiment showed that using manure acidified to pH5 or pH6 as feedstock delayed organic matter degradation for 7–10 days, although pH6 had no negative effect on compost maturity. Acidification significantly decreased NH3 emission from both storage and composting, however, excessive acidification (pH5) enhanced N2O emissions (18.6%) during composting. When manure was acidified to pH6, N2O (17.6%) and CH4 (20%) emissions, and total GHG emissions expressed as global warming potential (GWP) (9.6%) were reduced during composting. Acidification of manure before composting conserved more N as NH4 + and NOx in compost product. Compared to the control, the labile, plant-available phosphorus (P) content in the compost product, predominately as water-soluble inorganic P, increased with manure acidification to pH5 and pH6. Acidification of manure to pH6 before composting decreases nutrient losses and gaseous emissions without decreasing the quality of the compost product. The techno-economic advantages of acidification should be further ascertained.

    Effect of arginine or glutamine supplementation and milk feeding allowance on small intestine development in calves
    Keulen, P. van; Khan, M.A. ; Dijkstra, J. ; Knol, F. ; McCoard, S.A. - \ 2020
    Journal of Dairy Science 103 (2020)5. - ISSN 0022-0302 - p. 4754 - 4764.
    L-arginine - L-glutamine - milk allowance - small intestine development

    The development of the small intestine (SI) is important for the health and growth of neonatal calves. This study evaluated the effect of arginine (Arg) and glutamine (Gln) supplementation and 2 levels of milk allowance on the histomorphological development of the SI in preweaning calves. Sixty mixed-sex Friesian × Jersey calves (3–5 d of age) were offered reconstituted whole milk (125 g/L, 26% fat, 26% protein) at either high (20% of arrival body weight/d; HM) or low (10% of arrival body weight/d; LM) milk allowance without (Ctrl) or with supplementary Arg or Gln (at 1% of milk dry matter) in a 2 × 3 factorial design (n = 10/treatment). After 35 d on the diets, all calves were slaughtered to collect tissues for examination of SI development. Calves in the HM group had higher milk intake, total weight gain, and average daily gain compared with LM calves, but no effect of AA supplementation nor an interaction between milk allowance and AA supplementation was observed. For the duodenum, we observed an AA by milk allowance interaction for villus height and width, and goblet cell number per villus (HM-Arg > HM-Gln > HM-Ctrl), and villus height to crypt depth ratio (HM-Arg > HM-Gln = HM-Ctrl), but no effect of AA supplementation in the LM group. Goblet cell numbers per 100 μm of SI were greater in Arg-supplemented calves than in unsupplemented controls, with Gln-supplemented calves intermediate to but not different from the other groups. Epithelium thickness was greater in LM than in HM calves. Villus density, crypt depth, and muscle thickness did not differ between groups. For the jejunum, there was an AA by milk allowance interaction for villus height, villus surface area, and villus height to crypt depth ratio (HM-Arg = HM-Gln > HM-Ctrl), with no effect of AA supplementation in the LM groups. Amino acid supplementation affected goblet cell number per villus (HM-Gln > HM-Ctrl calves, HM-Arg intermediate), and both LM-Arg and LM-Gln calves had greater numbers than LM-Ctrl calves. Villus width, crypt depth, and muscle thickness were greater in HM than LM calves but there was no effect of AA supplementation. Villus density, goblet cell number per 100 μm of SI, and epithelium thickness were unaffected by AA supplementation and milk allowance. Milk allowance and AA supplementation had no effect on SI morphology in the ileum. Increasing milk allowance improved villus height, width, and surface area but only in Arg- or Gln-supplemented calves, not in control calves. The observed changes in development may be important for intestinal functionality, integrity, and barrier function in preweaning calves, potentially through increased cell growth and proliferation or reduced levels of cellular atrophy.

    Two decades of forest-related legislation changes in European countries analysed from a property rights perspective
    Nichiforel, Liviu ; Deuffic, Philippe ; Thorsen, Bo Jellesmark ; Weiss, G. ; Hujala, Teppo ; Keary, Kevin ; Lawrence, A. ; Avdibegović, Mersudin ; Dobšinská, Zuzana ; Feliciano, Diana ; Gorriz Mifsud, Elena ; Hoogstra-Klein, M.A. ; Hrib, Michal ; Jarský, Vilém ; Jodłowski, Krzysztof ; Lukmine, Diana ; Pezdevšek Malovrh, Špela ; Nedeljković, Jelena ; Bouriaud, Laura - \ 2020
    Forest Policy and Economics 115 (2020). - ISSN 1389-9341
    In the last two decades, attention on forests and ownership rights has increased in different domains of international policy, particularly in relation to achieving the global sustainable development goals. This paper looks at the changes in forest-specific legislation applicable to regular productive forests, across 28 European countries. We compare the legal framework applicable in the mid-1990s with that applicable in 2015, using the Property Rights Index in Forestry (PRIF) to measure changes across time and space.
    Space-time statistical analysis and modelling of nitrogen use efficiency indicators at provincial scale in China
    Liu, Yingxia ; Heuvelink, Gerard B.M. ; Bai, Zhanguo ; He, Ping ; Xu, Xinpeng ; Ma, Jinchuan ; Masiliūnas, Dainius - \ 2020
    European Journal of Agronomy 115 (2020). - ISSN 1161-0301
    Nitrogen use efficiency (NUE) is crucial to establish efficient fertilizer application guidelines that balance crop yield, economic return and environmental sustainability. Although there are quite a few researches about the spatial and temporal variation of NUE, little work has been done on modelling NUE through deriving empirical relationships with explanatory environmental variables and exploring their relative importance quantitatively. The space-time patterns of NUE indicators (i.e., the Partial Factor Productivity of nitrogen, PFPN, and the Partial Nutrient Balance of nitrogen, PNBN) at provincial scale in China were derived and related to environmental covariates using stepwise multiple linear regression. PFPN was higher in east and south China than in central and west China and was smaller than 30 kg kg−1 yr−1 in most provinces, while PNBN was moderate in most provinces (0.41–0.50 kg kg−1 yr−1) and low (< 0.40 kg kg−1 yr−1) in south China. The national PFPN declined slightly from 32 kg kg−1 in 1978 to 27 kg kg−1 in 1995 and went up gradually to reach 38 kg kg−1 in 2015. The national PNBN decreased from 0.53 to 0.36 kg kg−1 from 1978 to 2003, thereafter stabilizing at around 0.40 kg kg−1 yr−1 between 2004 and 2015. The multiple linear regression models explained 74 % of the variance of PFPN and PNBN. The main explanatory variables of PFPN were planting area index of sugar crop (32 % of the R-square), followed by Arenosols (12 %), planting area index of oil crop (8 %), planting area index of vegetables (5 %), silt content (5 %) and total potassium (5 %). For PNBN, the variation was mainly attributed to mean annual daytime surface temperature (28 % of the R-square), planting area index of crops (beans 20 %, orchards 10 % and vegetables 9 %) and wet day frequency (5 %). The results of this study indicate that crop types, temperature and soil properties are important variables that determine NUE. These should be considered by policy makers when agricultural land development decisions are made in order to balance NUE and productivity (i.e., agronomy and environment).
    Consequences of extending the voluntary waiting period for insemination on ovarian cyclicity and reproductive performance in dairy cows
    Ma, J. ; Burgers, E.E.A. ; Lam, T.G.J.M. ; Kemp, B. ; Knegsel, A.T.M. van - \ 2020
    In: Wias Annual Conference 2020 WIAS - p. 69 - 69.
    Extending lactation length in dairy cows is of interest because it reduces the number of calving events per cow per time unit and herewith possibly reduces the risk for health and fertility problems associated with calving and start of lactation. Extending lactation length can be realized by deliberately delaying first insemination, i.e. extending the voluntary waiting period for first insemination (VWP). Moreover, it can be hypothesized that insemination later in lactation is related with improved ovarian cyclicity. The aim of the present study was to evaluate the effect of an extended VWP on ovarian cyclicity and reproductive performance of dairy cows. Holstein-Friesian dairy cows (N=150) were blocked by parity, calving season and expected FPCM. Within blocks, cows were randomly assigned to one of three VWP (50, 125 or 200 days). Cows were artificially inseminated at first estrous after end of VWP. Milk samples were collected three times a week until pregnancy and analysed for progesterone concentration. At least two succeeding milk samples with progesterone concentration of 2 ng/mL or greater were used to indicate the onset of luteal activity (OLA) and to classify ovarian cycles. Ovarian cycles were classified as: normal (ovarian cycles of 18 to 24 days in length), short (ovarian cycles <18 days) and prolonged (ovarian cycles >24 days). Extended VWP of 200-d and 125-d VWP was related with increased number of cycles within first100 DIM compared with 50-d VWP (2.6, 2.8 vs 1.6, P <0.01). During 100 DIM around the end of VWP (-50 till 50 d), 200-d VWP treatment had greater percentage of cows with normal cycles (90.55 vs 53.48, P <0.01) and lower percentage of cows with short (0.79 vs 11.24, P =0.02) or prolonged cycles (8.66 vs 35.28, P=0.01) compared with 50-d VWP treatment. Cows with 200-d VWP had less days till pregnancy after end of VWP compared with cows with 125-d or 50-d VWP (31.17 vs 54.78, 58.33 d, P=0.04). In conclusion, extended VWP could improve reproductive performance, which was related with shorter intervals to pregnancy after end VWP, greater cycle number before insemination and greater percentage of normal cycles around VWP.
    MEMOTE for standardized genome-scale metabolic model testing
    Lieven, Christian ; Beber, Moritz E. ; Olivier, Brett G. ; Bergmann, Frank T. ; Ataman, Meric ; Babaei, Parizad ; Bartell, Jennifer A. ; Blank, Lars M. ; Chauhan, Siddharth ; Correia, Kevin ; Diener, Christian ; Dräger, Andreas ; Ebert, Birgitta E. ; Edirisinghe, Janaka N. ; Faria, José P. ; Feist, Adam M. ; Fengos, Georgios ; Fleming, Ronan M.T. ; García-Jiménez, Beatriz ; Hatzimanikatis, Vassily ; Helvoirt, Wout van; Henry, Christopher S. ; Hermjakob, Henning ; Herrgård, Markus J. ; Kaafarani, Ali ; Kim, Hyun Uk ; King, Zachary ; Klamt, Steffen ; Klipp, Edda ; Koehorst, Jasper J. ; König, Matthias ; Lakshmanan, Meiyappan ; Lee, Dong Yup ; Lee, Sang Yup ; Lee, Sunjae ; Lewis, Nathan E. ; Liu, Filipe ; Ma, Hongwu ; Machado, Daniel ; Mahadevan, Radhakrishnan ; Maia, Paulo ; Mardinoglu, Adil ; Medlock, Gregory L. ; Monk, Jonathan M. ; Nielsen, Jens ; Nielsen, Lars Keld ; Nogales, Juan ; Nookaew, Intawat ; Palsson, Bernhard O. ; Papin, Jason A. ; Patil, Kiran R. ; Poolman, Mark ; Price, Nathan D. ; Resendis-Antonio, Osbaldo ; Richelle, Anne ; Rocha, Isabel ; Sánchez, Benjamín J. ; Schaap, Peter J. ; Malik Sheriff, Rahuman S. ; Shoaie, Saeed ; Sonnenschein, Nikolaus ; Teusink, Bas ; Vilaça, Paulo ; Vik, Jon Olav ; Wodke, Judith A.H. ; Xavier, Joana C. ; Yuan, Qianqian ; Zakhartsev, Maksim ; Zhang, Cheng - \ 2020
    Nature Biotechnology 38 (2020)3. - ISSN 1087-0156 - p. 272 - 276.
    What happens under the reef? A study towards the identity and functioning of the cryptobenthic community in two contrasting coral reef habitats
    Streekstra, M.A. ; Folkers, M. ; Schoon, Bart ; Jorissen, Hendrikje ; Nugues, Maggy M. ; Goeij, Jasper M. De; Murk, A.J. ; Osinga, R. - \ 2020
    In: WIAS Annual Conference 2020. - WIAS - p. 28 - 28.
    Hidden in the gaps, cracks and crevices of the coral reef three-dimensional framework,complex benthic communities reside. These communities are largely composed of filter feeders such as sponges and ascidians and it becomes increasingly clear that this community plays a vital role in retaining nutrients on the reef. Little is known on how the species composition of the crypto benthic community relates to its ecological functioning (e.g.biochemical cycling), despite the cryptic habitat being the largest surface area on coral reefs. Here we show -for the first time- how the composition of the crypto benthic community influences it’s biochemical cycling (oxygen and organic carbon) in two distinct reef habitats.These habitats are the hard coral dominated outer reef of Mo’orea (French Polynesia)and the ‘shifted’ reef of Curacao (Dutch Caribbean), where algae and cyanobacteriahave become the dominant benthos. In both locations, we deployed 36 experimental structures using the established ARMS (Autonomous Reef Monitoring Structures) methodology.We adapted the methodology by 1) adjusting the size of the standard ARMS (to eachmini ARMS totaling a 0.14m2 surface area) and 2) equipping part of the structures with nutrient dispensers to test for the effect of environmental perturbation on community composition and functioning. After 15 months of colonization, we quantified metabolic fluxes(respiration of oxygen in the light and dark, uptake of dissolved and total carbon, bacteria and nutrients) of the mini ARMS communities using in situ respiration chambers. We subsequently determined the composition of the sessile and mobile communities using pictures(Photoquad) and meta barcoding. Preliminary data from Mo’orea show a clear distinction between the upper surface and cryptic spaces, with 83% of the miniARMS being net phototrophicin the light (mean Pn 38.04 mmol O2 m-2 day-1) and heterotrophic during dark incubations (mean Rd -36.89 mmol O2 m-2 day-1). The upper surface of the ARMS were largely dominated by CCA, whereas ascidians were most abundant in the cryptic spaces. From the large mobile fraction (>2mm), we retrieved on average 5.6 phyla per ARMS and 213animals m-2, with gastropods (24%), bivalves (24%), crabs (21%) and hermit crabs (19%) being the most dominant groups. Future analyses will integrate carbon flux data with community composition to improve our understanding of the ecological role of the cryptobenthosin different reef systems.
    Elevated viscosities in a simulated moving bed for γ-aminobutyric acid recovery
    Schultze-Jena, A. ; Boon, M.A. ; Vroon, R.C. ; Bussmann, P.J.Th. ; Janssen, A.E.M. ; Padt, A. van der - \ 2020
    Journal of Separation Science 43 (2020)7. - ISSN 1615-9306 - p. 1256 - 1264.
    chromatography - concentration profile - productivity - simulated moving bed - viscosity

    Process streams of agro-food industries are often large and viscous. In order to fractionate such a stream the viscosity can be reduced by either a high temperature or dilution, the former is not an option in case of temperature sensitive components. Such streams are diluted prior to chromatographic fractionation, resulting in even larger volumes and high energy costs for sub-sequential water removal. The influence of feed viscosity on the performance of simulated moving bed chromatography has been investigated in a case study of the recovery of a γ-aminobutyric acid rich fraction from tomato serum. This work addresses the chromatographic system design, evaluates results from a pilot scale operation, and uses these to calculate the productivity and water use at elevated feed concentration. At the two higher feed viscosities (2.5 and 4 mPa·s) water use is lower and productivity higher, compared to the lowest feed viscosity (1 mPa·s). The behavior of the sugars for different feed viscosities can be described well by the model using the ratio of feed to eluent as dilution factor. The behavior of γ-aminobutyric acid is highly concentration dependent and the recovery could not be accurately predicted.

    Gastrointestinal Bioaccessibility and Colonic Fermentation of Fucoxanthin from the Extract of the Microalga Nitzschia laevis
    Guo, Bingbing ; Oliviero, Teresa ; Fogliano, Vincenzo ; Ma, Yuwei ; Chen, Feng ; Capuano, Edoardo - \ 2020
    Journal of Agricultural and Food Chemistry 68 (2020)7. - ISSN 0021-8561 - p. 1844 - 1850.
    digestion - fermentation - fucoxanthin - microalgae

    The extract of microalga Nitzschia laevis (NLE) is considered a source of dietary fucoxanthin, a carotenoid possessing a variety of health benefits. In the present study, the bioaccessibility and deacetylation of fucoxanthin were studied by simulated in vitro gastrointestinal digestion and colonic batch fermentation. In the gastric phase, higher fucoxanthin loss was observed at pH 3 compared to pH 4 and 5. Lipases are crucial for the deacetylation of fucoxanthin into fucoxanthinol. Fucoxanthinol production decreased significantly in the order: pure fucoxanthin (25.3%) > NLE (21.3%) > fucoxanthin-containing emulsion (11.74%). More than 32.7% of fucoxanthin and fucoxanthinol was bioaccessible after gastrointestinal digestion of NLE. During colon fermentation of NLE, a higher loss of fucoxanthin and changes of short-chain fatty acid production were observed but no fucoxanthinol was detected. Altogether, we provided novel insights on the fucoxanthin fate along the human digestion tract and showed the potential of NLE as a promising source of fucoxanthin.

    Influence of agricultural organic inputs and their aging on the transport of ferrihydrite nanoparticles: From enhancement to inhibition
    Qian, Xiaoyan ; Ma, Jie ; Weng, Liping ; Chen, Yali ; Ren, Zongling ; Li, Yongtao - \ 2020
    Science of the Total Environment 719 (2020). - ISSN 0048-9697
    Aging - Biochar - Ferrihydrite nanoparticles - Swine manure - Transport

    Organic matter effectively regulates nanoparticles transport. However, little is known about the effect of agricultural organic inputs on the transport of ferrihydrite nanoparticles (FHNPs) during aging. In this study, columns were filled with sand mixed with varying proportions of pristine, water-processing, or alkali-processing biochar or swine manure and used to simulate the release of organic matter and changes in surface roughness of sand grains during field aging. The influence of these factors on FHNPs transport was investigated using column experiments. The dissolved organic matter (DOM) (0.008–24.8 mg L−1) released from agricultural organic inputs decreased the zeta potential of the FHNPs from 30.8 mV to 14.6–-48.9 mV and further caused electrostatic repulsion, osmotic repulsion, and elastic-steric repulsion between FHNPs and mixed sand, thus enhancing FHNPs transport. Ferrihydrite nanoparticles transport increased with increasing content of biochar and swine manure due to the increased amount of DOM. However, with the presence of organic inputs, surface roughness up to a certain degree (the increase in specific surface area up to 4.6 m2) became the dominant inhibition factor affecting FHNPs transport. After DOM release, agricultural organic inputs decreased the enhancement of FHNPs transport; with the increase input, their rougher surface gradually increased inhibition of FHNPs transport. The strongest FHNPs retention in the alkali-processing biochar (0.2–10%) or swine manure (1–2%) mixed sand columns indicated that fully aged agricultural organic inputs strongly inhibited FHNPs transport. Our findings provided novel insights into the critical influence of agricultural organic inputs and their aging on FHNPs transport, which changed gradually from enhancement to inhibition gradually.

    Review of climate control and space allowance during transport of pigs (version 1.0)
    Bracke, M.B.M. ; Herskin, M.S. ; Marahrens, M.A. ; Gerritzen, M.A. ; Spoolder, H.A.M. - \ 2020
    EURCAW-Pigs - 34 p.
    pigs - animal welfare - transport of animals - climate - space - meat animals - finishing - animal production - animal health - transport - animal behaviour - occupation
    An automated modular microsystem for enzymatic digestion with gut-on-a-chip applications
    Haan, P. de; Ianovska, M.A. ; Mathwig, K. ; Bouwmeester, H. ; Verpoorte, E. - \ 2020
    In: 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017. - Chemical and Biological Microsystems Society (21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017 ) - ISBN 9780692941836 - p. 1593 - 1594.
    Digestion - Enzyme kinetics - Gut-on-a-chip - Organ-on-a-chip

    Gut-on-a-chip models have gained attention as replacements for other cell-based assays or animal studies in drug development or toxicological studies. These models aim to provide a more accurate representation of the in vivo situation in form and function; however, no digestive processes have been included in these systems so far. This work describes a miniaturized digestive system based on artificial digestive juices that digest liquid samples in a series of three microreactors. After optimization of the pH value of juices and mixtures, samples leading to fluorescent products were digested to demonstrate enzyme functionality and to determine kinetic parameters.

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