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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    Assessment of the genetic and clinical determinants of fracture risk : Genome wide association and mendelian randomisation study
    Trajanoska, Katerina ; Morris, John A. ; Oei, Ling ; Zheng, Hou Feng ; Evans, David M. ; Kiel, Douglas P. ; Ohlsson, Claes ; Richards, J.B. ; Rivadeneira, Fernando ; Forgett, V. ; Leong, A. ; Ahmad, O.S. ; Laurin, C. ; Mokry, L.E. ; Ross, S. ; Elks, C.E. ; Bowden, J. ; Warrington, N.M. ; Kleinman, A. ; Willems, S.M. ; Wright, D. ; Day, F.R. ; Murray, A. ; Ruth, K.S. ; Tsilidis, K.K. ; Ackert-Bicknell, C.L. ; Bassett, J.H.D. ; Eerden, B.C.J. van der; Gautvik, K. ; Reppe, S. ; Williams, G.R. ; Medina-Gómez, C. ; Estrada, K. ; Amin, N. ; Enneman, A.W. ; Li, G. ; Liu, C.T. ; Liu, Y. ; Xiao, S.M. ; Lee, S.H. ; Koh, J.M. ; Tang, N.L.S. ; Cummings, S.R. ; Brown, M. ; Groot, L. de; Jukema, J.W. ; Lips, P. ; Meurs, J.B.J. van; Smith, A.V. ; Tian, S. - \ 2018
    BMJ: British Medical Journal 362 (2018). - ISSN 0959-8146

    Objectives To identify the genetic determinants of fracture risk and assess the role of 15 clinical risk factors on osteoporotic fracture risk. Design Meta-analysis of genome wide association studies (GWAS) and a two-sample mendelian randomisation approach. Setting 25 cohorts from Europe, United States, east Asia, and Australia with genome wide genotyping and fracture data. Participants A discovery set of 37 857 fracture cases and 227 116 controls; with replication in up to 147 200 fracture cases and 150 085 controls. Fracture cases were defined as individuals (>18 years old) who had fractures at any skeletal site confirmed by medical, radiological, or questionnaire reports. Instrumental variable analyses were performed to estimate effects of 15 selected clinical risk factors for fracture in a two-sample mendelian randomisation framework, using the largest previously published GWAS meta-analysis of each risk factor. Results Of 15 fracture associated loci identified, all were also associated with bone mineral density and mapped to genes clustering in pathways known to be critical to bone biology (eg, SOST, WNT16, and ESR1) or novel pathways (FAM210A, GRB10, and ETS2). Mendelian randomisation analyses showed a clear effect of bone mineral density on fracture risk. One standard deviation decrease in genetically determined bone mineral density of the femoral neck was associated with a 55% increase in fracture risk (odds ratio 1.55 (95% confidence interval 1.48 to 1.63; P=1.5×10'68). Hand grip strength was inversely associated with fracture risk, but this result was not significant after multiple testing correction. The remaining clinical risk factors (including vitamin D levels) showed no evidence for an effect on fracture. Conclusions This large scale GWAS meta-analysis for fracture identified 15 genetic determinants of fracture, all of which also influenced bone mineral density. Among the clinical risk factors for fracture assessed, only bone mineral density showed a major causal effect on fracture. Genetic predisposition to lower levels of vitamin D and estimated calcium intake from dairy sources were not associated with fracture risk.

    Feeding in the transitional period
    Eerden, Ellen van - \ 2018
    New poultry nutrition
    Eerden, Ellen van - \ 2018
    Poultry health: the role of nutrition in controlling and enhancing intestinal integrity
    Eerden, Ellen van - \ 2018
    Development of the microbial balance in the intestinal tract to explain gut health
    Eerden, Ellen van - \ 2018
    Superior Stability of Au/SiO2 Compared to Au/TiO2 Catalysts for the Selective Hydrogenation of Butadiene
    Masoud, Nazila ; Delannoy, Laurent ; Schaink, Herrick ; Eerden, Ad van der; Rijk, Jan Willem de; Silva, Tiago A.G. ; Banerjee, Dipanjan ; Meeldijk, Johannes D. ; Jong, Krijn P. de; Louis, Catherine ; Jongh, Petra E. de - \ 2017
    ACS Catalysis 7 (2017)9. - ISSN 2155-5435 - p. 5594 - 5603.
    butadiene - catalyst - gold - selective hydrogenation - stability - supported nanoparticles

    Supported gold nanoparticles are highly selective catalysts for a range of both liquid-phase and gas-phase hydrogenation reactions. However, little is known about their stability during gas-phase catalysis and the influence of the support thereon. We report on the activity, selectivity, and stability of 2-4 nm Au nanoparticulate catalysts, supported on either TiO2 or SiO2, for the hydrogenation of 0.3% butadiene in the presence of 30% propene. Direct comparison of the stability of the Au catalysts was possible as they were prepared via the same method but on different supports. At full conversion of butadiene, only 0.1% of the propene was converted for both supported catalysts, demonstrating their high selectivity. The TiO2-supported catalysts showed a steady loss of activity, which was recovered by heating in air. We demonstrated that the deactivation was not caused by significant metal particle growth or strong metal-support interaction, but rather, it is related to the deposition of carbonaceous species under reaction conditions. In contrast, all the SiO2-supported catalysts were highly stable, with very limited formation of carbonaceous deposits. It shows that SiO2-supported catalysts, despite their 2-3 times lower initial activities, clearly outperform TiO2-supported catalysts within a day of run time. (Graph Presented).

    Occurrence of virus-induced COPD exacerbations during four seasons
    Djamin, Remco S. ; Uzun, Sevim ; Snelders, Eveline ; Kluytmans, Jan J.W. ; Hoogsteden, Henk C. ; Aerts, Joachim G.J.V. ; Eerden, Menno M. Van Der - \ 2015
    Bmc Infectious Diseases 47 (2015)2. - ISSN 2374-4235 - p. 96 - 100.
    Chronic obstructive pulmonary disease - Exacerbations - Seasonal patterns - Virus

    In this study, we investigated the occurrence of viral infections in acute exacerbations of chronic obstructive pulmonary disease (COPD) during four seasons. Viral infections were detected by the use of real-time reverse transcriptase polymerase chain reaction on pharyngeal swabs. During a 12-month period pharyngeal swabs were obtained in 136 exacerbations of 63 patients. In 35 exacerbations (25.7%) a viral infection was detected. Most viral infections occurred in the winter ( n = 14, 40.0%), followed by summer ( n = 9, 25.7%), autumn ( n = 6, 17.1%), and spring ( n = 6, 17.1%). Rhinovirus was the most frequently isolated virus ( n = 19, 51.4%), followed by respiratory syncytial virus ( n = 6, 16.2%), human metapneumovirus ( n = 5, 13.5%), influenza A ( n = 4, 10.8%), parainfluenza 4 ( n = 2, 5.4%), and parainfluenza 3 ( n = 1, 2.7%). This study showed that virus-induced COPD exacerbations occur in all four seasons with a peak in the winter months. However, the distribution of rhinovirus infections showed a different pattern, with most infections occurring in July.

    Effects of inclusion of hydrolyzed yeast on the immune response and performance of piglets after weaning
    Molist, F. ; Eerden, E. van; Parmentier, H.K. ; Vuorenmaa, J. - \ 2014
    Animal Feed Science and Technology 195 (2014). - ISSN 0377-8401 - p. 136 - 141.
    growth-performance - saccharomyces-cerevisiae - natural antibodies - weanling pigs - nutrient digestibility - weaned piglets - supplementation - polysaccharides - challenge - chickens
    The aim of this study was to examine whether yeast derivative (YD) based on brewery yeast hydrolyzate added to a post-weaning diet affected performance and immune responses in weaning pigs. One hundred and twenty pigs were allocated to 20 pens, taking initial body weight into account, and were distributed into two groups as follows: a negative control diet and the same diet supplemented with 2 g YD/kg. The YD used was Progut® (Hankkija Oy/Suomen Rehu, Hyvinkää, Finland). At days 7 and 21 of the experiment, half of the piglets per group were challenged intramuscularly with 1 mL of a solution of 20% sheep red blood cells (SRBC) in sterile phosphate buffered saline (PBS). At days 0, 14, 21 and 28 of the experiment, blood samples from the challenged piglets were obtained and acute-phase proteins (Pig-MAP), natural antibodies of the IgM- and IgG-isotype binding to keyhole limpet hemocyanin (KLH), and agglutinating antibody titers to SRBC were measured. Yeast derivative inclusion improved feed conversion ratio (P=0.025) for the overall period, tended to increase IgG (P=0.087) and IgM (P=0.061) antibodies in serum-binding KLH, and increased (P=0.037) SRBC agglutination titers. Collectively, these data suggest that YD supplementation as 2 g Progut®/kg to weanling pigs triggered the immune system to a more responsive state without penalizing the animal performance which could potentially be beneficial for overcoming disease challenges. Piglets fed with 2 g Progut®/kg for 28 days after weaning also showed an improvement in feed conversion ratio.
    Differences in fluorescence of doxycycline in chicken bone depending on dosage and treatment time
    Groot, M.J. ; Ossenkoppele, J.S. ; Bruchem, G.D. van; Eerden, E. van; Klis, J.D. van der; Nielen, M.W.F. - \ 2014
    Effects of herbal products in vitro and in vivo
    Groot, M.J. ; Pikkemaat, M.G. ; Driessen-van Lankveld, W.D.M. ; Eerden, M.E. van; Klis, J.D. van der - \ 2013
    diervoeding - geneeskrachtige kruiden - voedertoevoegingen - antimicrobe-eigenschappen - anti-infectieuze middelen - diergezondheid - animal nutrition - herbal drugs - feed additives - antimicrobial properties - antiinfective agents - animal health
    The aim of the study was to examine the antimicrobial action of herbal feed additives and the relation between this antimicrobial action and performance data in vivo and gut histology (villus/crypt ratio) as parameter for gut health.
    Effecten van kruidenproducten in vitro en in vivo
    Groot, M.J. ; Pikkemaat, M.G. ; Driessen, J.J.M. ; Eerden, E. van; Klis, J.D. van der - \ 2013
    Nederlands Tijdschrift voor Fytotherapie 4 (2013). - ISSN 1384-8925 - p. 16 - 20.
    Specific serum antibody responses following a Toxoplasma gondii and Trichinella spiralis co-infection in swine
    Bokken, G. ; Eerden, E. van; Opsteegh, M. ; Augustijn, M. ; Graat, E.A.M. ; Franssen, F. ; Görlich, K. ; Buschtöns, S. ; Tenter, A.M. ; Giessen, J.W.B. van der; Bergwerff, A.A. ; Knapen, F. van - \ 2012
    Veterinary Parasitology 184 (2012)2-4. - ISSN 0304-4017 - p. 126 - 132.
    tissue cysts - pigs - infections - mice - netherlands - diagnosis - britovi - pork
    The aim of this study was to examine the dynamics of parasite specific antibody development in Trichinella spiralis and Toxoplasma gondii co-infections in pigs and to compare these with antibody dynamics in T. spiralis and T. gondii single infections. In this experiment, fiftyfour pigs were divided into five inoculated groups of ten animals, and one control group of four animals. Two groups were inoculated with a single dose of either T. gondii tissue cysts or T. spiralis muscle larvae, one group was inoculated simultaneously with both parasites and two groups were successively inoculated at an interval of four weeks. Specific IgG responses to the parasites were measured by ELISA. T. gondii burden was determined by MC-PCR carried out on heart muscle and T. spiralis burden by artificial digestion of diaphragm samples. Specific IgG responses to T. gondii and T. spiralis in single and simultaneously inoculated animals showed a respective T. gondii and T. spiralis inoculation effect but no significant interaction of these parasites to the development of specific antibodies with the serum dilutions used. Moreover, our data showed that the specific IgG response levels in groups of animals successively or simultaneously co-infected were independent of a respective previous or simultaneous infection with the other parasite. Additionally, no differences in parasite burden were found within groups inoculated with T. gondii and within groups inoculated with T. spiralis. Conclusively, for the infection doses tested in this experiment, the dynamics of specific antibody development does not differ between single and simultaneous or successive infection with T. gondii and T. spiralis. However, lower parasitic doses and other ratios of doses, like low-low, low-high and high-low of T. gondii and T. spiralis in co-infection, in combination with other time intervals between successive infections may have different outcomes and should therefore be studied in further detail.
    The need for future wetland bird studies: scales of habitat use as input for ecological restoration and spatial water management
    Platteeuw, M. ; Foppen, R.P.B. ; Eerden, M.R. van - \ 2010
    Ardea 98 (2010)3. - ISSN 0373-2266 - p. 403 - 416.
    phalacrocorax-carbo-sinensis - european harriers circus - purple heron - netherlands - population - information - landscape - corridors - drought - climate
    All over Europe, wetlands have decreased in size, lost their original dynamics and became fragmented as the consequence of an ever increasing human land use. These processes have resulted in losses of nature values, among which declines in marshland bird populations. Ecological restoration of wetland systems follows from initiatives like EU Bird and Habitat Directives and Water Framework Directive, but may be, in itself, too costly to be widely applied. More promising perspectives to reinforce the wetland part of the ecological network Natura 2000 might come into focus when combined with spatial water management which is primarily aimed at more sustainable safety against flooding. In this way, the wetland network may acquire a wider public and political support. Knowledge on scale-related habitat use of wetland birds can play a role in the process of spatial planning. We illustrate this point by distinguishing four levels of spatial and temporal habitat use by wetland birds, and giving examples for each. The four levels are: (1) birds on stopover sites during migration, (2) territorial breeding birds, (3) colonial breeding birds, and (4) staging birds on wintering sites. This asks for ecological coherence on different scales, e.g. on the international level of migration flyways, on the regional level of landscapes and on the local level of individual wetlands. It is advocated that wetland ecologists dedicate themselves more specifically to quantifying the relevant data on habitat use of birds on each of these scale levels. Meanwhile, spatial planners should try to incorporate them into their efforts in realising combinations of ecological restoration or rehabilitation of wetlands and solutions for sustainable water management. These combinations might turn the tide for some seriously threatened species of marshland and wetland birds.
    Residual feed intake in young chickens : effects on energy partitioning and immunity
    Eerden, E. van - \ 2007
    Wageningen University. Promotor(en): Bas Kemp; Mart de Jong, co-promotor(en): Henry van den Brand. - [S.l.] : S.n. - ISBN 9789085045939 - 168
    jonge kippen - voeropname - efficiëntie - middelentoewijzing - energiegebruik - experimentele infectie - immuniteitsreactie - immuniteit - pullets - feed intake - efficiency - resource allocation - energy consumption - experimental infection - immune response - immunity
    Keywords: chicken, residual feed intake, resource allocation, immune response, Salmonella Enteritidis, energy partitioning.

    The continuous selection in farm animals for efficient production and high production levels may have led to animals that are "programmed" to put a lot of resources in production processes, at the expense of resources for maintenance processes, among which the immune system. When efficiently and non-efficiently producing animals in a population are discriminated, it is hypothesized that non-efficient animals are better able to reallocate resources from production processes to maintenance processes than efficient animals. Non-efficient animals may, thus, be better off than efficient animals when maintenance processes are under pressure.

    Residual feed intake is used as a trait to discriminate efficient and non-efficient animals. It is defined as the difference between observed feed intake and expected feed intake; in this thesis, expected feed intake is based on metabolic body weight and growth. Animals that eat more than expected have a high residual feed intake and are considered non-efficient, whereas animals that eat less than expected have a low residual feed intake and are considered efficient.

    The research described in this thesis was carried out with pullets. Pullets are young, growing female chickens that do not produce eggs yet. Pullets were rated from high to low residual feed intake as a phenotypic trait; animals with the highest and lowest values for residual feed intake were selected for further research. Immune responses to non-replicating antigens and to live Salmonella Enteritidis bacteria were investigated.

    The results showed that non-efficient pullets had a higher feed intake than efficient pullets, but body weight and growth were equal in efficient and non-efficient pullets. Energy partitioning trials showed that non-efficient pullets spent more energy on maintenance processes than efficient pullets. However, an infection with Salmonella Enteritidis did not lead to repartitioning of energy from production processes to maintenance processes. It was concluded that a Salmonella Enteritidis infection is not energetically costly. Efficient pullets had a lower immune status than non-efficient pullets in situations where the animals were not infected with Salmonella Enteritidis, whereas during a Salmonella Enteritidis infection the efficient pullets had higher immune responses than non-efficient pullets. It is suggested that efficient and non-efficient pullets, as measured by residual feed intake, may have different "immune coping styles".
    Profits and losses of dietary efficiency with respect to immune reactivity
    Eerden, E. van; Brand, H. van den; Kemp, B. - \ 2006
    Dietary efficiency: waste not, want not?
    Eerden, E. van; Brand, H. van den; Kemp, B. - \ 2006
    Energy Partitioning and Thyroid Hormone Levels During Salmonella enteritidis Infections in Pullets with High or Low Residual Feed Intake
    Eerden, E. van; Brand, H. van den; Heetkamp, M.J.W. ; Decuypere, M.P. ; Kemp, B. - \ 2006
    Poultry Science 85 (2006)10. - ISSN 0032-5791 - p. 1775 - 1783.
    growing layer hens - laying hens - food-consumption - divergent selection - growth-hormone - egg-production - body-weight - efficiency - chicken - lines
    This experiment was conducted to investigate whether feed efficiency, as measured by residual feed intake as a phenotypic trait, affects energy partitioning in pullets that have received Salmonella inoculation as an immune challenge. In each of 8 trials, energy partitioning was measured during 5 wk in 15-wk-old efficient (R¿) and nonefficient (R+) pullets, which were housed per efficiency group in 2 identical climate respiration chambers. After 1 wk of adaptation, the pullets in 4 trials were orally inoculated with 108 cfu of Salmonella enteritidis; pullets in the remaining trials were not inoculated and served as controls. Heat production was calculated from continuous recordings of O2 consumption and CO2 production. Energy and N partitioning were recorded on a weekly basis. Blood samples for analyses on thyroid hormones were taken at 16, 17, and 19 wk of age. There were no interactions between efficiency type and Salmonella treatment or Salmonella treatment effects in energy partitioning, except for a short-term increase in heat production in inoculated pullets. Nonefficient pullets had higher gross energy and ME intake, higher estimated ME for maintenance, lower ME:gross energy ratio, and higher total heat production and nonactivity-related heat production compared with R¿ pullets. Triiodothyronine levels in R+ pullets were higher at 16 and 17 wk but were lower at 19 wk of age compared with R¿ pullets. Thyroxine levels were higher in R¿ at 16 wk and showed interactions between efficiency type and Salmonella treatment at 17 and 19 wk of age. Body weights and spleen weights did not differ between efficiency groups. Nonefficient pullets had higher heart, liver, and ovary weights and more large yellow follicles than R¿ pullets. There were no Salmonella effects on body and organ weights. We conclude that R+ pullets have a faster running energy metabolism and that they put more resources into organ development than R¿ pullets. Inoculation with Salmonella has a short-term effect on nonactivity-related heat production but does not affect energy partitioning, regardless of efficiency type
    Detection of egg yolk antibodies reflecting Salmonella enteritidis infections using a surface plasmon resonance biosensor
    Thomas, M.E. ; Bouma, A. ; Eerden, E. van; Landman, W.J.M. ; Knapen, F. van; Stegeman, J.A. ; Bergwerff, A.A. - \ 2006
    Journal of Immunological Methods 315 (2006)1-2. - ISSN 0022-1759 - p. 68 - 74.
    laying hens - typhimurium - chickens - elisa - assay - immunosensor - netherlands - antigens - serum
    A surface plasmon resonance (SPR) biosensor assay was developed on the basis of a lipopolysaccharide antigen of Salmonella enterica serovar enteritidis (S. enterica serovar enteritidis) to detect egg yolk antibodies against S. enterica serovar enteritidis. This biosensor assay was compared to two commercial ELISA kits based on LPS antigen and flagellar antigen. A number of 163 egg yolk and combined egg white and yolk samples from chickens experimentally infected with S. enterica serovar enteritidis and 90 egg yolk and combined egg white and yolk samples from uninfected chickens were analyzed. Receiver operating characteristic analysis of the data calculated a diagnostic sensitivity of 82% and a diagnostic specificity of 100%. The within-day coefficient of variation of a positive internal-control egg yolk was 1%. The SPR biosensor assay was able to detect antibodies in a significantly higher percentage of known positive samples than the commercial ELISA's. The anticipated use of the SPR biosensor assay is to determine the S. enterica serovar enteritidis serostatus of non-vaccinated layer hens
    Een analyse van de mogelijke gevolgen van de aanleg van IJburg tweede fase voor watervogels in de SBZ IJmeer
    Schekkerman, H. ; Eerden, M.E. van; Rijn, S. van; Roos, M. - \ 2006
    Wageningen : Alterra (Alterra-rapport 1363) - 95
    vogels - milieueffect - wildbescherming - stedelijke planning - nederland - amsterdam - birds - environmental impact - wildlife conservation - urban planning - netherlands - amsterdam
    De gemeente Amsterdam heeft vergevorderde plannen om in het IJmeer, grenzend aan het Vogelrichtlijngebied (SBZ, Natura 2000 gebied) IJmeer, de tweede fase van de wijk IJburg te realiseren. In dit rapport wordt (1) beschreven welke specifieke waarden van het IJmeer volgens de Vogelrichtlijn dienen te worden beschermd, (2) verkend welke invloed IJburg II op deze waarden zal hebben en of daarbij sprake is van significante gevolgen in het kader van de Vogelrichtlijn, en (3) aangegeven welke mitigerende maatregelen de verstorende effecten van IJburg II kunnen voorkomen. Het rapport zal mede de basis vormen onder een nieuwe versie van het bestemmingsplan voor IJburg II, die vervolgens aan een `passende beoordeling¿ in het kader van de NB-wet 1998 zal worden onderworpen
    Salmonella Challenge Affects the Antibody Isotype Profile of Bile in Hens Differing in Metabolic Efficiency
    Cotter, P.F. ; Eerden, E. van - \ 2006
    Poultry Science 85 (2006)5. - ISSN 0032-5791 - p. 861 - 865.
    residual feed-intake - growing layer hens - enteritidis infection - immune-responses - chicken bile - iga - lectin - selection - subclass - jacalin
    Gel precipitation reactions determined antibody isotypes in bile from hens differing in dietary efficiency. Ouchterlony double diffusion employing ¿-chain specific goat-anti-chicken IgA, rabbit anti-chicken IgG, goat anti-chicken IgM, black turtle bean (BTB), and Jacalin lectins as precipitating reagents detected bile IgA, IgG, and IgM from Salmonella exposed and nonexposed hens. The IgA was present in 1 of 3 forms designated by reagent and frequency: IgAB (precipitated by BTB lectin) 100%; IgAA (precipitated by anti-¿ chain antibody) 98%, and IgAJ (precipitated by Jacalin) 97%. That both BTB and Jacalin precipitates contain IgA was confirmed by immuno-dot blots using affinity purified ¿-chain specific antibody, establishing each as IgA glycoforms. Three measurements of Ouchterlony precipitates were made; d1 and d2 indicate diffusion from sample or reagent wells, ? indicates arc length. Mean values for ?, estimating quantity, were IgAA (11.3 mm) and IgAB (11.6 mm) and IgAJ (8.3 mm). The crescent shape IgAJ arc and its slower diffusion (d1) suggested its molecular weight is greater than either IgAA or IgAB. Arc lengths of individual samples were not significantly correlated suggesting that these are independent components of bile. Oral Salmonella enteritidis challenge resulted in a highly significant difference in bile IgA profiles. The IgAJ arc lengths (?) in R¿ hens increased by 20% over those in nonchallenged R¿ hens. Conversely S. enteritidis challenge was associated with a decrease of 10% in IgAJ arc lengths in nonefficient (R+) hens. Salmonella enteritidis challenge was not associated with arc length differences in either IgAA or IgAB. The IgG was present in all specimens, and in 9 of 59 (15%) 2 forms were detected. The IgG quantity was unaffected by either efficiency type or S. enteritidis challenge. The IgM was detected in only 2 of 59 (3.4%) specimens. Our observations suggest IgA of bile is composed of multiple forms influenced both by diet efficiency status and S. enteritidis exposure. It appears that the latter resulted in an increased quantity of IgAJ in R¿ hens, and suggests the existence of functional differences among the various IgA types.
    Natural Anti-Gal and Salmonella-Specific Antibodies in Bile and Plasma of Hens Differing in Diet Efficiency
    Cotter, P.F. ; Eerden, E. van - \ 2006
    Poultry Science 85 (2006)3. - ISSN 0032-5791 - p. 435 - 440.
    residual feed-intake - growing layer hens - enteritidis infection - immune-responses - selection - chickens
    Specific anti-Salmonella enteritidis (SE) and natural anti-¿-gal epitope (Gal¿1-3Galß-1-4GlcNAc-R; anti-Gal) antibodies were measured in plasma sample pools and individual bile specimens obtained from hens differing in diet efficiency. More SE somatic (O) and flagellar (H) antibodies were found in plasma pools from efficient hens (R¿) compared with nonefficient hens (R+) after oral challenge with live SE. Mean titers of somatic agglutinins in bile were 2.3 in R¿ hens and 1.9 in R+ hens (P = 0.06) following live challenge. Salmonella enteritidis antibodies were also found in bile of nonchallenged hens of both types but their levels were not significantly different. Flagellar (H) agglutinin scores were higher in SE-challenged hens compared with nonchallenged hens (3.1 vs. 2.1; P is less than or equal to 0.004) but efficiency types did not differ. Bile also contained high titers of the anti-Gal antibody indicated by the agglutination of glutaraldehyde-stabilized rabbit erythrocytes. The average titer of all SE-nonexposed hens was 9.0 corresponding to 1:5,120 when corrected for the initial dilution and expressed in conventional terms. Salmonella enteritidis exposure was associated with higher anti-Gal titers. The average anti-Gal titer for all SE-exposed hens was 10.0, corresponding to 1:10,240 in conventional terms; this difference was significant (P is less than or equal to 0.016). Diet efficiency type-associated differences in anti-Gal titers were not significant. Collectively, our data indicate that diet efficiency status is not associated with compromised Salmonella-specific immune responses. Rather it appears that the immune responses of diet efficient hens (R¿) are also more efficient. This is because R¿ hens produced higher levels of O- and H-type antibody only as the result of direct exposure to living SE. On the contrary, R+ hens produced H-type antibody because of challenge with heat-killed SE, a circumstance that will not result in disease. Moreover, the hen type difference does not seem to occur at the expense of innate immunity as measured by anti-Gal antibody levels
    PRISM Pechora River Integrated System Management : final report first phase: 2003-2005
    Eerden, M.R. van; Leummens, H. ; Ponomarev, V. ; Pedroli, G.B.M. ; Roos, M. ; Vries, M. - \ 2005
    Lelystad [etc.] : RIZA [etc.] - 16
    waterbeheer - rivieren - delta's - rusland - aquatische ecosystemen - water management - rivers - deltas - russia - aquatic ecosystems
    PRISM (Pechora River Integrated System Management)
    Eerden, M.R. van; Leummens, H. ; Ponomarev, V. ; Pedroli, G.B.M. ; Roos, M. ; Vries, M. - \ 2005
    Lelystad : RIZA - ISBN 9789036957328 - 56 p.
    Investeren of emigreren: maakindustrie biedt Nederlandse landbouw toekomstperspectief
    Eerden, H. van; Pehrson, T. ; Smit, W. ; Vries, H.S.M. de; Sluys, H. van - \ 2004
    Link 2004 (2004)4. - ISSN 1568-1378
    Phenotypic Selection for Residual Feed Intake and Its Effect on Humoral Immune Responses in Growing Layer Hens
    Eerden, E. van; Brand, H. van den; Parmentier, H.K. ; Jong, M.C.M. de; Kemp, B. - \ 2004
    Poultry Science 83 (2004)9. - ISSN 0032-5791 - p. 1602 - 1609.
    food-consumption - laying hens - divergent selection - genetic-variation - domestic-fowl - body-weight - trade-offs - responsiveness - immunology - efficiency
    According to the resource allocation theory, animals have to make a trade-off between resource-demanding life traits to obtain maximal fitness. Artificial selection toward efficient producing farm animals, however, may have created animals that have an impaired ability to divert resources to maintenance processes, such as responding to immune challenges. Residual feed intake (RFI), defined as the difference between observed feed intake (FI) and expected feed intake based on metabolic BW and growth, was used as a measure for feed efficiency. Individual BW and FI of 352 pullets were recorded weekly from 4 until 14 wk of age to estimate RFI. The top 50 efficient R– and the top 50 nonefficient R+ birds were selected. BW and BW gain in both groups were similar. FI and RFI, however, were significantly higher in R+ birds. Thirty animals out of every group were randomly allocated to 1 of 3 treatments: immunization with keyhole limpet hemocyanin (KLH), Mycobacterium butyricum, or heat-inactivated Salmonella enteritidis bacteria. Antibody titers against KLH, M. butyricum, or Salmonella lipopolysaccharide did not differ between R+ and R– birds. The antibody titer against Salmonella protein was higher in R+ birds. We concluded that a population of chickens from a commercial breed shows considerable variation in RFI. Specific antibody production against KLH, M. butyricum, and S. enteritidis lipopolysaccharide, however, is not influenced by efficiency in terms of RFI. R+ animals may have a higher level of nonantigen specific antibodies, as indicated by the higher antibody response to Salmonella protein.
    Residual Feed Intake and its Effect on Salmonella enteritidis Infection in Growing Layer Hens
    Eerden, E. van; Brand, H. van den; Vries Reilingh, G. de; Parmentier, H.K. ; Jong, M.C.M. de; Kemp, B. - \ 2004
    Poultry Science 83 (2004)11. - ISSN 0032-5791 - p. 1904 - 1910.
    laying hen
    Previous phenotypic selection on residual feed intake (RFI) identified 20 efficient R- chickens and 20 nonefficient R+ chickens. Residual feed intake was defined as the difference between observed feed intake (FI) and expected FI based on metabolic BW and BW gain, and was used as a measure for feed efficiency. Body weight and BW gain were similar for both groups. Feed intake and RFI were significantly higher in R+ birds. It is hypothesized that nonefficient R+ birds are more flexible to divert resources from production processes toward maintenance processes, thus being better capable of handling a bacterial challenge. Chickens of both groups were randomly allocated to immunization with heat-inactivated Salmonella enteritidis bacteria, or inoculation with live Salmonella bacteria. Transportation to the isolation units caused a decrease in FI in R+ birds. This may reflect a particular way of coping with stress in R+ birds. More R+ birds stopped bacterial shedding considering a nonshedding interval of 10 or 11 d (P = 0.041). Nonantigen-specific antibody responses against keyhole limpet hemocyanin (KLH) were higher in R- birds. We conclude that R+ birds are able to keep their metabolism at a higher level, as indicated by higher heart and liver weights, and that Salmonella infection leads to reduced heart, liver, and gizzard weights. Oviduct weight and number of small yellow follicles were reduced in infected birds. Antigen-specific antibody responses were not different between the groups, indicating high priority for this parameter as a life trait. Possible differences in stress susceptibility between efficient and nonefficient chickens need further examination.
    Effect of phenotypic selection for residual feed intake on antibody responses in growing layer hens
    Eerden, E. van; Brand, H. van den; Parmentier, H.K. ; Jong, M. de; Kemp, B. - \ 2004
    In: XXII World's Poultry Congress, Istanbul, Tyrkey, 8-13 June 2004. - Turkey : - p. 798 - 798.
    Interactions in the utilisation of small fish by piscivorous fish and birds, and the fishery in IJsselmeer
    Mous, P.J. ; Dekker, W. ; Leeuw, J.J. de; Eerden, M.R. van; Densen, W.L.T. van - \ 2003
    In: Interactions between fish and birds: implications for management / Cowx, I.G, Oxford : Blackwell Science - ISBN 9780632063857 - p. 84 - 118.
    Interactions in the utilisation of smalll fish and birds, and the fishery in IJsselmeer.
    Mous, P.J. ; Dekker, W. ; Leeuw, J.J. de; Eerden, M.R. van; Densen, W.L.T. van - \ 2003
    In: Interactions between fish and birds: Implications for management / Cowx, I.G., Oxford : Blackwell Science - ISBN 9780632063857 - p. 84 - 118.
    An outlook for a national integrated nitrogen policy
    Erisman, J.W. ; Vries, W. de; Kros, J. ; Oenema, O. ; Eerden, L. van der; Smeulders, S.M. - \ 2001
    Environmental Science & Policy 4 (2001)2-3. - ISSN 1462-9011 - p. 87 - 95.
    Reactive nitrogen in the environment is a current and future major policy issue. Nitrogen pollution and its emissions are difficult to control, because they are associated with two of the most important human needs i.e. food and energy. In the Netherlands, several measures have been taken to decrease emissions with varying success. So far policy has been focussed on individual environmental issues related to specific sources. This paper summarises the results of a study to analyse the nitrogen problem in the Netherlands in an integrated way All relevant aspects are taken into account simultaneously. This was done by deriving regional agricultural nitrogen production ceilings, including all relevant nitrogen flows in agriculture and most relevant effects, i.e. protection of ground and surface water from nitrate pollution and N-eutrophication, controlling NH3 volatilisation in view of impacts on terrestrial ecosystems and reducing NOx and N2O emissions in view of climate change policies. For agriculture, nitrogen ceilings provide a good basis for regulating nitrogen through fertiliser use and feed import. Results show that reactive nitrogen production in the Netherlands should be decreased by 50–70% in order to reach the ceilings necessary to protect the environment against nitrogen pollution from agriculture.
    Evaluatie van de verzuringsdoelstellingen: de onderbouwing
    Albers, R. ; Beck, J. ; Bleeker, A. ; Bree, L. van; Dam, J. van; Eerden, L. v.d.; Freijer, J. ; Hinsberg, A. van; Marra, M. ; Salm, C. v.d.; Tonneijck, A. ; Vries, W. de; Wesselink, L. ; Woretelboer, F. - \ 2001
    Bilthoven : RIVM
    milieubeleid - evaluatie - milieueffect - zure depositie - waarden - modellen - nederland - terrestrische ecosystemen - atmosferische depositie - beleidsevaluatie - luchtverontreiniging - milieu - vegetatie - verzuring - environmental policy - evaluation - environmental impact - acid deposition - values - models - netherlands - terrestrial ecosystems
    Lucht en Landbouw. Schade door luchtverontreiniging in de gewasteelt en economische gevolgen
    Tonneijck, A.E.G. ; Eerden, L.J.M. van der; Wijnands, J.J.M. - \ 2001
    Lucht 18 (2001)2. - ISSN 0925-9953 - p. 35 - 38.
    gewassen - oogstschade - gewasverliezen - luchtverontreiniging - crops - crop damage - crop losses - air pollution
    Beschrijving van de effecten van luchtverontreiniging op gewassen, waarna enig inzicht wordt gegeven in de economische schade
    Effects of vapours of chlorpropham and ethofumesate on wild species
    Franzaring, J. ; Kempenaar, C. ; Eerden, L.J.M. van der - \ 2001
    Environmental Pollution 114 (2001). - ISSN 0269-7491 - p. 21 - 28.
    Effects of vapours of two herbicides on plantlets of fourteen wild higher plant species and two bryophytes were screened in fumigation experiments using foliar injury, chlorophyll fluorescence and growth as response parameters. After vaporisation of the herbicides for 48 h, concentrations in the chambers reached 77 g m−3 in the chlorpropham treatments and 184 ng m−3 in the ethofumesate treatments. Despite the higher concentrations of the volatile chlorpropham (vapour pressure, VP: 1.3 mP), plants showed no foliar injury, but vapours of this herbicide caused leaf crinkling in the agriophyte Agrostemma githago. The less volatile ethofumesate (VP: 0.56 mP) caused foliar injury in all higher species, with lowest no observed effect concentrations (NOECs) of 75 ng m−3. Chlorpropham affected growth only in Agrostemma, while ethofumesate reduced growth in one third of the higher plant species. Chlorophyll fluorescence proved to be a less suitable response parameter compared to foliar injury and growth. No adverse effects were observed in mosses, probably due to the slow growth and hence small doses of herbicides taken up. The extent of foliar injury due to ethofumesate showed a weak positive relationship to relative growth rates and specific leaf area in the tested higher plant species.
    Beoordeling van luchtkwaliteitscriteria voor bescherming van natuur : vaststellen van bruikbaarheid van luchtverontreinigingsconcentraties voor risicoschattingen met de Natuurplanner
    Eerden, L.J.M. van der; Franzaring, J. ; Dobben, H.F. van - \ 2000
    Wageningen : Plant Research International (Nota / Plant Research International 58) - 26
    luchtverontreiniging - fytotoxiciteit - ozon - ecosystemen - air pollution - phytotoxicity - ozone - ecosystems
    Analyse van de stikstofproblematiek in Nederland; een eerste verkenning
    Erisman, J.W. ; Vries, W. de; Kros, H. ; Oenema, O. ; Eerden, L.J. van der; Zeijts, H. van - \ 2000
    Petten : ECN - 69
    nitraten - emissie - bodemverontreiniging - verontreinigingsbeheersing - nederland - nitrates - emission - soil pollution - pollution control - netherlands
    De milieuproblematiek in Nederland wordt voor een groot deel bepaald door de stikstofbelasting, afkomstig van landbouw, verkeer en industrie. Hierbij gaat het om de omzetting van onschadelijk stikstof in een reactieve vorm, waarna het kan leiden tot schadelijke effecten. Maatregelen die gericht zijn op het terugdringen van de totale hoeveelheid emissie zien het feitelijke probleem over het hoofd. De overmaat aan reactief stikstof in Nederland maakt het noodzakelijk dit als uitgangspunt te nemen voor beleid. Visie vanuit ECN en Alterra
    Interactions between climate change and nitrogen deposition, with emphasis on ammonia
    Dueck, Th.A. ; Eerden, L.J.M. van der - \ 2000
    In: Trace gas emissions and Plants / Singh, S.N., Dordrecht : Kluwer Academic Publishers - p. 291 - 307.
    Accumulation of persistent organic pollutants (POPs) in plants
    Franzaring, J.H. ; Eerden, L.J.M. van der - \ 2000
    Basic and Applied Ecology 1 (2000). - ISSN 1439-1791 - p. 25 - 30.
    Accessing the chronic effect of atmospheric tetrachloroethylene (PER) in plants
    Franzaring, J. ; Eerden, L.J.M. van der; Dijk, C.J. van; Helsper, J.P.F.G. ; Pikaar, P.J.J. ; Nijhuis, E.H. ; Tonneijck, A.E.G. - \ 2000
    Wageningen : Plant Research International (Note 48)
    Verslag deelproject 1: verkenning van de effecten van etheen op de opbrengst van aardappel
    Grashoff, C. - \ 2000
    In: Verbeterde normstelling voor effecten op gewassen van immissies van etheen rond DSM :Nota 4 / van der Eerden, L.J.M., van Dijk, C.J.,
    Vergelijking van effectrisico' s van gereduceerd en geoxideerd stikstof: eindverslag project 10266: stikstofonderzoekprogramma 1997-1999
    Eerden, L. van der - \ 2000
    Wageningen : Plant Research International - 60
    stikstof - nitraat - ammoniak - stikstofoxiden - milieueffect - luchtverontreiniging - depositie - emissie - nitrogen - nitrate - ammonia - nitrogen oxides - environmental impact - air pollution - deposition - emission
    Verbeterde normstelling voor effecten op gewassen van immissies van etheen rond DSM. Jaarrapport 1999: Probleemverkenning en bouw van een model-subroutine voor etheen
    Eerden, L.J.M. van der; Dijk, C.J. van; Grashoff, C. ; Kleef, J. van; Oijen, M. van; Pot, C.S. ; Schapendonk, A.H.C.M. ; Tonneijck, A.E.G. - \ 2000
    Wageningen : Plant Research International (Nota 4) - 33 p.
    Accumulatie van fluoriden in kalkpapieren en gras rond Aluminiumfabriek Delfzijl. November 1998 tot en met oktober 1999
    Dijk, C.J. van; Alfen, A.J. van; Eerden, L.J.M. van der - \ 2000
    Wageningen : Plant Research International (Nota 3) - 19 p.
    Biomonitoringprogramma rondom Huisvuilcentrale Noord-Holland. - Januari t/m december 1999
    Dijk, C.J. van; Alfen, A.J. van; Eerden, L.J.M. van der; Kok, M.T. de - \ 2000
    Wageningen : Plant Research International (Nota 40) - 31 p.
    Is de depositie van PAK's op gewassen een probleem?
    Dijk, C. van; Eerden, L. van der; Franzaring, J. - \ 2000
    Lucht 18 (2000)2. - ISSN 0925-9953 - p. 35 - 38.
    wegtransport - motorvoertuigen - verkeer - luchtverontreiniging - emissie - overheidsbeleid - nederland - road transport - motor cars - traffic - air pollution - emission - government policy - netherlands
    Een beleidsmedewerker van de VROM-Raad schetst de argumentatie van het standpunt van de Raad t.a.v. terugdringing van de emissie veroorzaakt door autoverkeer
    Wintering Tufted Ducks Aythya fuligula diving for zebra mussels Dreissena polymorpha balance feeding costs within narrow margins of their energy budget
    Leeuw, J.J. de; Eerden, M.R. van; Visser, G.H. - \ 1999
    Journal of Avian Biology 30 (1999)2. - ISSN 0908-8857 - p. 182 - 192.
    Diving ducks face the strongly cooling properties of aquatic environments. In experiments with Tufted Ducks Aythya fuligula feeding on zebra mussels Dreissena polymorpha in outdoor cages, we measured changes in food consumption and diving behaviour in relation to water temperature (3-22°C). Water efflux and daily energy expenditure (DEE) were measured using doubly-labelled water. Tufted Ducks swallow mussels whole and crush the shells in the gizzard. Due to the low flesh content of mussels, daily mussel consumption was extremely high in winter (up to 3 times the duck body mass of 600 g). Water efflux was 6.5 to 13 times higher than allometrically predicted, with a maximum of 1.11·d-1. Because of high water turnover rates, DEE estimates from doubly-labelled water measurements were variable, but on average agreed with DEE estimates obtained from food consumption and time-energy budgets (ca. 5% higher values). DEE increased with lower temperatures from 2.5 (summer, 20°C) to more than 4 times the basal metabolic rate (winter, 3°C). Costs of thermoregulation and heating up ingested mussels (as estimated from the theoretical caloric heat) primarily explained the high DEE in winter. At lower temperatures, dive duration was shorter and less time was spent selecting small mussels at the bottom, while more larger mussels were brought up and were ingested at the water surface. Thereby, the energy costs of crushing shells probably increased in favour of reducing diving costs. The narrow margins of the energy budget, wherein costs must be balanced, imply that food availability and water temperature are important attributes to winter distributions of diving ducks.
    Invloed van GS-4 Glasreiniger op de groei van fresia 'Cote d'Azur'. Deskundigenonderzoek inzake De Bloois/Paul Sosef b.v. en Paul Sosef b.v./Mardenkro b.v. Zaak-/rolnummers: 96.0052 en 96.2353
    Eerden, L.J.M. van der; Dijk, C.J. van - \ 1999
    Wageningen : AB-DLO (Nota 204) - 25 p.
    Effecten van ozon op gewassen in Nederland. Een evaluatie op basis van veldwaarnemingen
    Eerden, L.J.M. van der; Tonneijck, A.E.G. ; Dijk, C.J. van - \ 1999
    Wageningen : AB - 27
    oogstschade - luchtverontreiniging - ozon - peulvruchten - klavers - nederland - crop damage - air pollution - ozone - grain legumes - clovers - netherlands
    Bodem - plant - milieu
    Eerden, L.J.M. van der; Werf, A. van der - \ 1999
    In: Jaarverslag 1998 Wageningen : AB-DLO - p. 22 - 28.
    Short-term exposure to atmospheric ammonia does not affect frost hardening of needles from three- and five-year-old Scots pine trees
    Clement, J.M.A.M. ; Hasselt, P.R. van; Eerden, L.J.M. van der; Dueck, Th.A. - \ 1999
    Journal of Plant Physiology 154 (1999). - ISSN 0176-1617 - p. 775 - 780.
    Effects of herbicide vapours on non-target plants
    Franzaring, J. ; Kempenaar, C. ; Pikaar, P.J.J. ; Eerden, L.J.M. van der - \ 1999
    Unknown Publisher
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