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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    Future of pig production in Romania : Options for governmental policy
    Bergevoet, R.H.M. ; Hoste, R. ; Verweij-Novikova, I. ; Jongeneel, R.A. ; Gonzalez Martinez, Ana ; Hennen, W.H.G.J. - \ 2020
    Wageningen Economic Research - 97 p.
    MagnetGrid : Model description and user guide
    Diogo, Vasco ; Hennen, Wil ; Verma, Monika ; Oudendag, Diti ; Kuiper, Marijke - \ 2020
    Wageningen : Wageningen Economic Research (Wageningen Economic Research report 2020-004) - 65
    MagnetGrid is een modulair economisch landgebruiksmodel dat ruimtelijk expliciete biofysische informatie combineert met macro-economische projecties. MagnetGrid visualiseert toekomstige agrarisch landgebruikspatronen gedreven door een combinatie van klimatologische en socioeconomische ontwikkelingen. Het model kwantificeert de impact van deze trends en de mogelijke uitruil tussen verschillende doelstellingen. De ruimtelijk expliciete analyses van MagnetGrid kunnen voor een breed publiek toegankelijk gemaakt worden door kaarten die veranderingen in landgebruik laten zien op wereld-, regio-, land- en lokaal niveau.
    Bodem- en waterkwaliteit in de Nederlandse landbouw : Relatie tussen bodemorganische stof en nitraatuitspoeling op melkveebedrijven op zandgrond
    Wal, A. van der; Hennen, W.H.G.J. ; Koeijer, T.J. de - \ 2019
    Bodem (2019)5. - ISSN 0925-1650 - p. 34 - 36.
    Transition support system approach for urban food security in the future : The case of Ghana
    Dijkshoorn-Dekker, Marijke ; Linderhof, Vincent ; Pinto, Vasco ; Hennen, Wil ; Oudendag, Diti ; Kuiper, Marijke ; Shutes, Lindsay - \ 2019
    Wageningen : Wageningen Economic Research (Report / Wageningen Economic Research 2019-057a) - ISBN 9789463439602 - 43
    The population of the world is becoming increasingly urbanised due to a combination of natural population growth and rural–urban migration. This will pose major challenges to feed the future population and meet the Sustainable Development Goals. Meeting these complex challenges requires an integrated approach. The transition support system (TSS) approach integrates decision support tools and stakeholder analyses for these complex issues. This study has focused attention on the application of decision support tools of the TSS approach that visualises the urgency of future food security as a proof of concept. To this end, the future food security of the city of Accra, the capital of Ghana, has been taken as a case study. The use of Global-Detector and its maps illustrated a quick way to downscale data and projections from MAGNET (Modular Applied GeNeral Equilibrium Tool) and perform spatial analyses without the burden of acquiring additional data. Downscaling of macroeconomic results of future projections provides insights into future urban food security. Giventhese insights, stakeholders might urge policy or interventions. The results of the exercise are largely determined by the availability of data and maps; in particular, the more detailed information is available, the more accurate the results of our exercise will be.
    Comparing cities of the world according to their food security risks and opportunities
    Hennen, Wil ; Diogo, Vasco ; Polman, Nico ; Dijkshoorn-Dekker, Marijke - \ 2018
    In: Sustainable Development and Planning X. - WIT Press (WIT Transactions on Ecology and the Environment ) - ISBN 9781784662912 - p. 953 - 962.
    Due to the combined effect of climate change, expected population growth and increased concentration of population in cities and towns, food insecurity in urban areas is becoming of increasing concern and is regarded as one of the most prominent development challenges for the 21st century. Cities differ with respect to their specific food security risks and opportunities of local food supply to meet the increasing demand for food. The tool “Global Metropolitan Detector” has been developed to compare cities of the world based on different dimensions of food security, particularly availability, accessibility, and affordability of food, risk of floods and climate change, and healthy diets. Worldwide publicly available datasets, e.g. from FAOSTAT, EarthStat and WorldClim, are used. These are separately converted (aggregated/disaggregated) to a homogenous 5 arc-minute grid and combined in the tool to calculate (by weighted average) and compare the demand and local supply of food, including the required area of land to meet the city-specific consumption needs (measured in “Food Metres”). The purpose is to benchmark 850 cities based on several aspects related to food security. The resulting benchmark of cities and their indicator values can be visualised in maps showing their position with respect to food security in general, or investigate particular aspects in more detail, e.g. cities having low/high flood risks or cities that are better able to meet the demand of (fresh) vegetables and fruit from local producers. The maps can support policymakers to identify causes and locations of food insecurity, and the indicative results – based on limited available worldwide data – can serve as an inducement for further investigation with more detailed data from cities.
    Instrumentarium Kosten Natuurbeleid 2018 - Status A : IKN versie 3.0
    Michels, R. ; Diogo, V. ; Hennen, W.H.G.J. ; Puister, L.F. - \ 2018
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 134) - 145
    The Cost of Nature Policies Tool (IKN) calculates the annual costs of the national ecological network under various scenarios. The tool is modularly constructed and in essence consists of several cost tables and a computational model. The purpose of the current report is to consolidate the model documentation and provide a quality assurance assessment. It contains a theoretical framework, a technical description of the computational model and cost tables, and a description of the operation of the model and of the data used. The quality of the calculations was evaluated by means of validation, verification, and sensitivity and uncertainty analyses of the model.
    GLB-scenario’s Noord-Nederland : In opdracht van de provincies Groningen, Fryslân en Drenthe
    Smit, A.B. ; Jager, J.H. ; Meer, R.W. van der; Hennen, W.H.G.J. ; Meulen, H.A.B. van der; Dolman, M.A. - \ 2018
    Wageningen : Wageningen Economic Research (Wageningen Economic Research 2018-054) - 82 p.
    Betere ziekteresistentie door fokken op natuurlijke antilichamen
    Berghof, Tom - \ 2018
    Insuring against phytosanitary risks in Dutch protected horticulture : A stochastic model to support policy makers
    Benninga, J. ; Asseldonk, M.A.P.M. Van; Hennen, W. ; Bremmer, J. - \ 2017
    Crop Protection 99 (2017). - ISSN 0261-2194 - p. 144 - 150.
    Dutch protected horticulture is exposed to notifiable phytosanitary pests which are listed in the Quarantine list of the European Union (European Union, 2000). It is uncertain when or which quarantine pest will occur and what financial consequences this will have. These financial consequences stem from measures to be undertaken by growers, as legally required by the European Union (EU, 2000).
    A method is presented to derive the probability distribution of phytosanitary costs, which can be used by government and industry to assess risk premiums and to determine the financial consequences of some subsidy on insurance premiums to create an adequate insurance fund. Volume streams and transmission of pests have been simulated for each subsequent product chain stage. Monte Carlo simulation is used to account for uncertainties in the probability of introduction, transmission and detection of a phytosanitary pest. The probability of phytosanitary costs was calculated for a number of selected crops in Dutch protected horticulture. These crop results has been enlarged for all the crops in protected horticulture.
    Praktijkmonitoring leghennen: resultaten
    Niekerk, T.G.C.M. van - \ 2017
    De Pluimveehouderij 47 (2017). - ISSN 0166-8250 - p. 28 - 30.
    Dit jaar is een overleg tussen sector en overheid voorzien om de stand van zaken te evalueren met betrekking tot het verbod op ingrepen dat per 1 september 2018 van kracht. Ten behoeve van deze evaluatie heeft Wageningen UR in de prakijk de uitval gemonitord van hennen men en zonder snavelbehandeling.
    Global-Detector; GIS- and Knowledge-based tool for a global detection of the potential for production, supply and demand
    Hennen, W.H.G.J. ; Daane, P.A.J. ; Duijvendijk, Kees van - \ 2017
    In: Proceedings of the 3rd International Conference on Geographical Information Systems Theory, Applications and Management; Porto, Portugal, 27-28 April 2017. - SciTePress - ISBN 9789897582523 - p. 161 - 168.
    Wageningen Economic Research has developed Global-Detector, a knowledge-based Geographic Information System that aims to detect the worldwide potential for production, demand and market strategies. At any spot in the world Global-Detector can show the values from a large amount of indicators, such as climate, infrastructure, and land characteristics. A large set of indicators is readily available for use without any GIS-processing, and the model builder together with the expert can instantly start building the knowledge base for the concerning research aim. Knowledge from experts is applied to combine relevant indicators to create new indicators. The concept of Global-Detector and 10 applications developed by this tool are described. As a generic tool with increased flexibility, Global-Detector has many application possibilities in a wide variety of fields.
    Impact of coupled EU support for sugar beet growing: more production, lower prices
    Smit, A.B. ; Jongeneel, R.A. ; Prins, H. ; Jager, J.H. ; Hennen, W.H.G.J. - \ 2017
    Wageningen : Wageningen Economic Research (Wageningen Economic Research report 2017-114) - ISBN 9789463432436 - 61
    In the 2013 negotiations on the ‘new CAP’ (Common Agricultural Policy), the option of voluntary coupled support (VCS) for sugar beet growing was introduced, which has been implemented from 2015 onwards by ten and from 2017 by eleven Member States. In 2017, a great change took place in the EU sugar sector through the abolishment of the sugar quota system, leading to an increase of competition between sugar companies and more fluctuating sugar prices than before. In such a dynamic context, questions were raised about potentially destabilising production and market effects of a VCS-regulation and about its legitimacy.
    Stalboekje Pluimvee 2017 : Handboek voor natuurlijke pluimveegezondheidzorg met kruiden en andere natuurproducten
    Groot, Maria ; Puls-van der Kamp, Ineke ; Asseldonk, Tedje van - \ 2017
    Wageningen : RIKILT Wageningen University & Research (RIKILT uitgave 2017.701) - 107
    pluimveehouderij - pluimvee - diergezondheid - dierenwelzijn - medicinale planten - geneeskrachtige kruiden - dierziektepreventie - dierlijke productie - biologische landbouw - handboeken - vleeskuikens - hennen - poultry farming - poultry - animal health - animal welfare - medicinal plants - herbal drugs - animal disease prevention - animal production - organic farming - handbooks - broilers - hens
    De stalboekjes zijn oorspronkelijk gemaakt voor de biologische veehouderij (versies 2009 en 2011) in het kader van onderzoek voor Biokennis. Deze uitgave is in 2014 en 2015 aangevuld met nieuwe middelen en inzichten en aangepast voor toepassing in de gangbare pluimveehouderij. Dit betekent o.a. dat een hoofdstuk over vleeskuikens is toegevoegd en het leghennen stuk is uitgebreid. Het streven om het gebruik van antibiotica terug te dringen vraagt om een ander management. Goede voeding, huisvesting en hygiëne zijn hierbij belangrijk. In dit boekje worden aanwijzingen gegeven om met natuurlijke middelen de gezondheid van de dieren te bevorderen en zo ziektes te voorkomen. Tevens kunnen middelen worden ingezet om de ernst van de ziekte te reduceren. Doel is tevens om de dierenartsen te informeren over de mogelijkheden van natuurproducten en de wetenschappelijke onderbouwing hiervan inzichtelijk te maken.
    Estimating costs of nature management in the European Union : Exploration modelling for PBL’s Nature Outlook
    Verburg, R.W. ; Hennen, W.H.G.J. ; Puister, L.F. ; Michels, R. ; Duijvendijk, Kees van - \ 2017
    Wageningen : Wageningen University & Research, Statutory Research Tasks Unit for Nature & the Environment (WOt-technical report 97) - 109
    A cost model was developed for the Nature Outlook of PBL Netherlands Environmental Assessment Agency.This cost model estimates one-off and recurrent costs of natural vegetation based on Corine land cover typesthroughout Europe. Cost estimates were made for the base year 2000 and future scenarios, including aTrend scenario based on current EU policies and normative perspectives, including Strengthening CulturalIdentity (SCI), Allowing Nature to Find its Way (NFW), Going with the Economic Flow (GEF) and Workingwith Nature (WWN). These scenarios all have a time horizon of 2050. To estimate various costs acomprehensive data analysis was carried out and a cost model was developed based on the IKN model forDutch Nature Policy. The model estimates costs of recurrent management in the base year on € 5.6 billionper year in the EU-28. Costs of recurrent management within the Natura 2000 network is estimated on € 3.5billion per year. Recurrent management costs in 2050 in the Trend scenario were estimated on € 5.2 billionper year. One-off costs of land purchase are estimated at € 450 per hectare per year and construction costs€ 1028 per hectare per year. One-off costs of the perspectives are 5.09 (SCI), 6.56 (NFW), 6.20 (GEF) and9.79 billion euro per year (WWN)
    Selectie van hennen voor ziekteresistentie op basis van natuurlijke antilichamen
    Parmentier, Henk - \ 2017
    Microorganism-mediated behaviour of malaria mosquitoes
    Busula, Annette O. - \ 2017
    Wageningen University. Promotor(en): W. Takken, co-promotor(en): J. de Boer. - Wageningen : Wageningen University - ISBN 9789463431156 - 199
    culicidae - anopheles gambiae - anopheles arabiensis - mosquito-borne diseases - disease vectors - animal behaviour - host-seeking behaviour - plasmodium falciparum - hosts - man - cows - hens - odours - culicidae - anopheles gambiae - anopheles arabiensis - ziekten overgebracht door muskieten - vectoren, ziekten - diergedrag - gedrag bij zoeken van een gastheer - plasmodium falciparum - gastheren (dieren, mensen, planten) - mens - koeien - hennen - geurstoffen

    Host-seeking is an important component of mosquito vectorial capacity on which the success of the other behavioural determinants depends. Blood-seeking mosquitoes are mainly guided by chemical cues released by their blood hosts. This thesis describes results of a study that determined the effect of microorganisms – host skin bacteria as well as malaria parasites – on host-seeking behaviour of female Anopheles gambiae sensu stricto and An. arabiensis in Homabay county, western Kenya. Semi-field and field experiments were conducted to determine the response of mosquitoes with different host preference to synthetic and natural odour blends from three vertebrate hosts, a human, a cow and a chicken. Screen house experiments were conducted to test whether specific skin bacteria or a mix of skin bacterial volatiles from the three vertebrate hosts mediate mosquito response. A review chapter in this thesis discusses how malaria parasites can manipulate human hosts to enhance their own transmission, by making the hosts more attractive to mosquitoes. Another experiment, using a dual-choice olfactometer, determined whether infection with malaria parasites increases human attractiveness to malaria mosquitoes, and whether the attractiveness of infected humans is Plasmodium falciparum-stage specific. Here, the same children participated in the study during infection with malaria parasites and after treatment with antimalarial drugs, artemisinin lumefantrine. Cage assays were further used to test mechanisms of attractiveness of P. falciparum-infected individuals using body odours or skin bacterial volatiles collected from the children at the two time points. Overall results show that skin bacterial volatiles play an important role in guiding mosquitoes with different host preferences to their specific host. For An. gambiae s.s., high (microscopic) densities of P. falciparum gametocytes (and not parasite-free, submicroscopic gametocytes or asexual stages of Plasmodium parasites) results into higher attractiveness of hosts, and body odours play a role in attractiveness of P. falciparum-infected humans. The results may help to develop more effective health policies and enable targeted interventions towards the most attractive hosts, which could contribute to reductions in malaria transmission. Identification of general or common attractive volatiles produced by the natural hosts as well as those from the gametocyte carriers may contribute to the development of an improved synthetic odour blend that may be used for sampling of mosquitoes with different host preferences. The use of powerful attractive odorants may result in reductions of vector-borne diseases transmitted by mosquitoes.

    How social unrest started innovations in a food supply chain
    Buurma, Jan ; Hennen, Wil ; Verwaart, Tim - \ 2017
    Journal of Artificial Societies and Social Simulation 20 (2017)1. - ISSN 1460-7425
    Content analysis - Dramaturgical analysis - Food supply chain - Opinion dynamics - Sociotechnical innovation

    Transitions leading to sociotechnical innovations in food supply chains have been described in dramaturgical analyses on the basis of newspaper articles and parliamentary records. The time scale of the transitions driven by aroused public opinion on issues such as animal welfare, is typically a decade. Actors are primary producers (farmers), other supply chain parties, authorities, NGOs voicing particular opinions, political parties, and consumers. In this article, their interactions and reactions to external events are modelled in an agent-based simulation based on opinion dynamics. The purposes of the simulation are (1) to validate that hypothetical relations derived from the dramaturgical analysis indeed lead to the emergence of the observed transitions, and (2) to study how the system could have developed under different behaviours or a different course of external events. Simulation results and a sensitivity analysis are discussed.

    Internationaal Productie Potentie Model : modelbeschrijving sierteelt
    Benninga, Jan ; Hennen, Wil ; Dijkxhoorn, Youri ; Galen, Michiel van - \ 2017
    Wageningen : Wageningen Economic Research (Wageningen Economic Research nota 2017-023) - 45
    The IPPMS model has been developed to map the global potential of floriculture production. For this purpose an overview of the relevant location theories was made and the development of floriculture production in a number of countries has been analysed. These insights have been used to develop a model structure in which factors, subfactors and indicators are determined by applying a phased approach. Subsequently, various experts have been ask to score the different factors, subfactors and indicators in order to weigh the model. With the IPPMS prototype various countries have been analysed in order to determine the attractiveness for floriculture production.
    Advancing Integrated Pest Management for Dermanyssus gallinae in laying hen facilities
    Mul, Monique F. - \ 2017
    Wageningen University. Promotor(en): Peter Groot Koerkamp; Marcel Dicke, co-promotor(en): Bastiaan Meerburg; D.R. George. - Wageningen : Wageningen University - ISBN 9789463430036 - 194
    hens - integrated pest management - dermanyssus gallinae - chicken housing - poultry housing - cages - animal production - poultry - animal health - hennen - geïntegreerde plagenbestrijding - dermanyssus gallinae - huisvesting van kippen - pluimveehokken - kooien - dierlijke productie - pluimvee - diergezondheid

    Pest and diseases in agricultural systems reduce the yield and quality of available food and feed worldwide. To meet the global growing demand for these products, losses should be reduced, preferably in a sustainable way. Integrated Pest Management (IPM) is a sustainable method that aims to minimize economic losses due to pests and diseases. IPM is generally based on eight steps: 1) prevention, 2) monitoring, 3) Decision‐making based on monitoring and thresholds, 4) use of non‐chemical methods, 5) pesticide selection, 6) reduced pesticide use, 7) anti‐resistance strategies, and 8) evaluation. With these steps, it is possible to prevent and control pests and diseases whilst deploying pesticides only as a last resort, thus reducing issues with pesticide contamination and resistance. Implementation of IPM by farmers increases when it is clear that it is compatible with existing farm processes and that it results in benefits for them.

    Successful IPM is most commonly applied against pests and diseases in crop production. When comparing the number of research articles on IPM in crop production with the number of research articles on IPM in animal production, it becomes clear that a paucity of scientific papers have been published on the latter. In laying hen facilities, for example, the application of all but basic IPM is still rare, even though the benefits of IPM have been described for poultry pests and disease vectors. In laying hen facilities Dermanyssus gallinae (PRM=poultry red mite), an hematophagous parasite, is common in many parts of the world. This mite is hard to control and negatively affects hen health, ‐welfare and farm economics, with estimated costs of infestation reaching 130 million euro per year in Europe. Currently, implementation of IPM for D. gallinae in laying hen facilities is limited to some combination of cleaning between flocks, limited preventive measures, and application of chemically or physically acting products. Implementation of more advanced IPM programmes for D. gallinae should therefore be considered to improve control prospects for this pest in laying hen facilities.

    This thesis focuses on the knowledge necessary for advancing IPM for D. gallinae in laying hen facilities. More specifically it focuses on prevention, monitoring and population modelling of this significant pest, with preventive measures and monitoring being key in advancing IPM per se.

    Knowledge assessment. To develop IPM for D. gallinae in laying hen facilities, biological and ecological knowledge of D. gallinae and knowledge of the effects of biotic and a‐biotic factors on this pests’ population development are required (Chapter 2). Therefore, a seminar was organized with eighteen D. gallinae researchers, from eight different European countries, with the aim of amassing existing expertise. This seminar gave insight into the current knowledge and knowledge gaps, regarding D. gallinae, also informing future perspectives and required developments for improving control of D. gallinae in laying hen facilities. During four sessions, the researchers present discussed lifecycle issues, effects of D. gallinae on hen and egg production, monitoring methods for D. gallinae infestations in laying hen facilities and control methods for D. gallinae in laying hen facilities. It was concluded that, where the D. gallinae lifecycle is concerned, a lot is still unknown about the mites feeding behaviour and preferences, mating behaviour, survival and conditions required for reproduction, host finding, aggregation cues, and attractant and repellent substances. When focusing on the effects of D. gallinae on the hen and on egg production it was agreed that a D. gallinae infestation is likely to result in higher water intake, lower egg production, lower feed conversion, increase of the immune response and reduced feather quality. It was also suggested that these effects may be hen genotype dependent, and further noted that effects are rarely quantified and need further investigation. Though monitoring was considered to be most important to improve control of D. gallinae, it was concluded that the available monitoring methods only indicate trends and a robust monitoring plan is lacking. The participants considered heating the hen house combined with a chemical treatment to be the most promising control method. Future promising developments for control of D. gallinae were considered to be use of vaccination, predatory mites and entomopathogenic fungi. The effects of D. gallinae on human health were not extensively discussed, but it was concluded that D. gallinae can be of medical significance, either directly via reaction to mite bites, or indirectly via human exposure to the chemicals used to control D. gallinae.

    Prevention. To acquire knowledge on the routes of introduction and spread of D. gallinae in laying hens facilities, the Hazard Analysis and Critical Control Points (HACCP) system was used (Chapter 3). The structure of this system allows the user to identify the risk factors and the critical control points for the introduction and spread of pathogens and parasites. This method was further used to identify preventive and corrective actions against D. gallinae. Four experts identified 41 hazards for introduction and spread of D. gallinae in laying hen facilities. To prevent these hazards, these experts made several suggestions for corrective actions. The risks of 41 hazards were calculated by multiplying the likelihood (1= occurring seldomly/theoretically; 2= occurring approximately once a year; 3= occurring repeatedly/more than once a year) by the severity (1 = low / single place in the facility becomes infested with D. gallinae; 2= moderate/ facility becomes infested at more than one location; 3= high/ D. gallinae infestation occurs at almost all places within the laying hen facility) of infestation. Hazards with a risk above 3, or with a severity of 3, were regarded as Critical Control Points (CCP’s). The CCP’s with the highest risks (risk of 6 and higher) for introduction of D. gallinae in laying hen facilities were: introduction of new flocks, containers and crates, the farmer and their employees. The CCP’s with the highest risks (risk of 6 and higher) for spread of D. gallinae between laying hen facilities were mice, rats and flies, wild birds, the feeding system, shared material and equipment, the egg conveyer belt, manure aeration pipes, removal of cadavers, visitors and external personnel, the farmer and their employees. The critical limits, a procedure step of the HACCP system which will be followed by a corrective action when the limit is exceeded, could not be determined as a result of lack of knowledge about thresholds. Subsequently, suggestions were made for monitoring the mite population and for documentation and validation. A checklist was devised using the corrective action from the CCP’s with the highest risks. This management tool for layer farmers was evaluated by UK and Dutch layer farmers as feasible and useful.

    Monitoring. The approach of Reflexive Interactive Design (RIO) was used to design an automated monitoring tool for D. gallinae, including an automated mite detection sensor (Chapter 6). The approach generated effective and technically feasible solutions for the key functions of the automated mite detection sensor, these being 1) the assessment of the D. gallinae population, 2) localizing the location and assessing the time of detection and 3) removal of mites from the detection area. Three different design concepts were designed using these solutions. As an additional, albeit proven essential step to the RIO approach, the main solutions were tested with live mites ensuring the alignment of solutions with the biology and behaviour of D. gallinae in vivo. A combination of the best solutions were developed in two different prototypes. These prototypes were subsequently tested in the laboratory and on farm. The prototype situated under the perch, with a through beam sensor and a pump to remove mites from the sensor after recording, was the most successful model. The designed automated mite detection sensor, or automated mite counter, for D. gallinae was subsequently validated in experimental laying hen cages with live birds and a growing population of D. gallinae (Chapter 5). The study resulted in 17 data points, each being a combination of ‘number of mites counted’ by the automated mite counter and the ‘number of mites present’ in the experimental laying hen cages. The regression line between the ‘number of mites counted’ and the ‘number of mites present’ demonstrated that the automated mite counter was able to track the D. gallinae population effectively.

    Population modelling. Step 2 of IPM describes not only pest monitoring in the field, but also ‘scientifically sound warning, forecasting and early diagnosis systems, where feasible, as well as the use of advice from professionally qualified advisors’. To advance this step for D. gallinae we developed and demonstrated an operational model, forecasting the mite population dynamics and evaluating and forecasting the effect of a treatment application for D. gallinae in laying hen facilities. For IPM this model and the required inputs need to be 1) labour‐extensive with minimal staff input, preferably automatically implementing “real time” measurement data into models; 2) operational, providing easily interpretable data, forecasting pest population dynamics and the moment a threshold will be exceeded; 3) able to compensate for different locations and time‐specific‐interactions and variables (e.g. management and temperature), enabling the handling of variability of the parameters of interest; 4) able to identify pest hotspots; 5) able to estimate and forecast treatment efficacy; and 6) applicable for different monitoring methods and therefore able to correct for monitoring measurement errors. Prior to the development of the population dynamics model a high variation in population growth was found which could be only partly explained by temperature, flock age, treatment, and compartment/laying hen facility. A substantial part of the total variation remained unexplained, or was found to be temporal. As a result of this partly temporal variation, a dynamic approach was suggested to improve the forecasting quality of a population dynamics model. With the input of population monitoring data, temperature data and information of the dates of any D. gallinae treatment interventions, the developed model was able to forecast the population dynamics of D. gallinae post treatment and without treatment while compensating for location and time specific interactions, handling the variability of the parameters. Moreover, this population dynamics model was able to forecast the D. gallinae population using data from different monitoring methods. Together with the models compatibility with different housing systems and its ability to forecast the mite population dynamics (requiring only three relative easy obtainable parameters), this model is an improvement over existing approaches for forecasting D. gallinae that could contribute to steps 2 and 8 of IPM for D. gallinae in laying hen facilities.

    The results from this study directly facilitate advanced IPM programmes for D. gallinae in laying facilities. The new ‘products’ developed are tools for prevention, monitoring, forecasting population dynamics and evaluating treatment effects, representing the requirements of IPM steps 1, 2, and 8. Indirectly the results may accelerate the development of new control measures, with knowledge acquired through use of the developed products it also is likely to contribute to IPM steps 3, 4, 6 and 8 in the future; e.g. the determination of an action threshold, and a tool advising farmers on the most effective and economic time for applying a corrective action or hotspot treatment for D. gallinae.

    With the obtained knowledge and new products implemented to control D. gallinae in laying hen farms, major advances can be made in IPM for this pest. More specifically, as a result of this work IPM for D. gallinae in laying hen facilities can be advanced by the identification of preventative control measures, the development of an automated monitoring tool and a model forecasting mite population dynamics and evaluating applied treatments. Consequently, the results of this study can be expected to improve hen health, welfare and farm economics for the egg production industry. In the future, advances in other IPM programmes can be expected when the obtained knowledge, tools and methods are transferred to other pest species in multiple sectors.

    Global Metropolitan-Detector : Application of Global-Detector for worldwide detection of metropolitan land use options
    Hennen, W.H.G.J. ; Wascher, D.M. - \ 2016
    - 13 p.
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