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.

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Degradation and excretion of the Fusarium toxin deoxynivalenol by an edible insect, the Yellow mealworm (Tenebrio molitor L.)
Broekhoven, S. van; Mota Gutierrez, J. ; Rijk, T.C. de; Nijs, W.C.M. de; Loon, J.J.A. van - \ 2017
World Mycotoxin Journal 10 (2017)2. - ISSN 1875-0710 - p. 163 - 169.
degradation - deoxynivalenol - edible insect - excretion

Insects could provide an alternative and more sustainable source of animal protein compared to conventional livestock. Yellow mealworms (Tenebrio molitor L.) can be grown on diets composed of organic by-products. However, these diets could be contaminated with mycotoxins. Thus far, little is known about possible retention, sequestration, excretion or detoxification of mycotoxins by edible insects. T. molitor larvae were grown on wheat flour naturally contaminated with mycotoxins among which deoxynivalenol (DON) was predominant (4.9 mg/kg), wheat flour spiked with 8 mg/kg pure DON, and uncontaminated wheat flour. Larval survival and weight gain on the three diets were compared. Survival was high for larvae on all dietary treatments (>98%) and no difference in weight gain was observed when comparing larvae grown on uncontaminated control diet with larvae grown on contaminated diets (P=0.091). Presence of mycotoxins in larvae and larval faeces was analysed using LC-MS/MS. No DON or DON-derivatives were detected in T. molitor after harvest of the larvae, pointing to degradation by the larvae. Excretion of DON in larval faeces was ca. 14% of the amount of DON ingested for larvae grown on naturally contaminated diet and ca. 41% for larvae grown on DON-spiked diet. These are promising results with respect to food safety of mealworms or derived products grown on mycotoxin-contaminated feed. However, enzymatic degradation of DON in T. molitor, as well as possible toxicity of the resulting metabolites, remain to be further investigated.

Towards improving the manure management chain
Hou, Yong - \ 2016
University. Promotor(en): Oene Oenema, co-promotor(en): Gerard Velthof. - Wageningen : Wageningen University - ISBN 9789462579620 - 215
manures - manure treatment - livestock - excretion - nitrogen - mitigation - methane - european union - mest - mestverwerking - vee - excretie - stikstof - mitigatie - methaan - europese unie

Animal manures are major sources of nutrients and organic matter, to be used to fertilize crops and improve soil quality. However, when not properly managed, these manures release considerable amounts of ammonia (NH3), nitrous oxide (N2O) and methane (CH4) into the air, and nitrogen (N) and phosphorus (P) to water bodies, which create a range of unwanted environment impacts. Nutrient losses from manure depend on the management activities and techniques used at different stages of the whole manure management chain, from animal feeding up to manure application to land. The trade-offs and co-benefits of emission mitigation measures and manure treatment technologies are as yet poorly understood, especially when taking the whole manure management chain into account. Moreover, the effects of combinations of measures and technologies have not been well analyzed, and analyses at national scales are lacking. The overall objective of this PhD thesis research is (i) to enhance the quantitative insight into the effects of emission mitigation measures and treatment technologies on emissions of NH3, N2O and CH4, and the recovery of N and P from animal manure in the whole management chain, and (ii) to explore the effects of combinations of measures and technologies to mitigate these emissions and to increase the N and P recovery.

In Chapter 2, methodologies for estimating N excretion factors for the main animal categories in member states of the European Union (EU) were reviewed. In Chapter 3, a transparent and uniform methodology for estimating annual feed use and N excretion per animal category for all countries of the EU-27 was developed, based on the energy and protein requirements of the animals and statistics of feed use and composition, animal number and productivity. In Chapter 4, firstly the impacts of a suite of NH3 mitigation measures on emissions of NH3, N2O and CH4 at individual stages of the manure management chain were analyzed by means of a meta-analysis of published data. Secondly, the overall impacts of alternative combinations of mitigation measures on emissions from the whole chain were evaluated through scenario analysis. Chapter 5 reports on an integrated assessment of the effects of manure treatment on NH3, N2O and CH4 emissions from manure management chains in EU-27 at the national level for 2010, using the model MITERRA-Europe. Whole-chain effects of implementing twelve treatment technologies in EU-27 on emissions and N and P recovery were further explored through scenario analyses. Chapter 6 reports on a survey conducted under various stakeholder groups with expertise in the domain of manure treatment in four European countries that have regions of high animal density. The survey addressed questions related to i) which factors facilitate and hinder the implementation of treatment technologies in practice, ii) which technologies have the most potential for successful adoption, and iii) how farm characteristics and the scale of the treatment operation affect priorities for adoption. The main conclusions of this PhD thesis are as follows:

In EU-27, the amounts of N and P in manure are as large as or larger than the total amounts of fertilizer N and P used annually. However, there is a huge spatial variation in manure production. Nutrient excretion factors per animal category also vary between countries, as a result of variations in feed use and animal productivity. Clearly, for accurate inventories of national emission there is a need for estimating nutrient excretion using country-specific feed use data.

Increasing the effectiveness of measures to mitigate NH3 and GHG emissions from animal manure requires proper combination of measures in the manure management chain. Lowering the dietary protein content in animal feed is an effective measure to reduce NH3 emissions and other N emissions at all stages of the manure management chain. Other measures may reduce emissions of a specific gas or emissions source, by which there is a risk of unwanted trade-offs in the manure management chain. Joint adoption of these measures with low-N feeding strategies and slurry acidification can greatly decrease the risk of pollution swapping.

Implementation of manure treatment is on average still limited in EU-27. Effects of manure treatment on NH3 and GHG emissions are therefore relatively small at EU level. Increasing the implementation of treatment technologies, including acidification, incineration and thermal drying, or optimized combinations of treatment technologies, can significantly contribute to achieving NH3 and GHG emission targets of EU environmental policies. Implementation of manure treatment technologies provides opportunities to improve the use of plant nutrients in manures, because of the release of manure products with different N/P ratios. Applying acidification technology and optimized combination of NH3 emission mitigation measures increase the N recovery from animal manure, and can decrease the demand of mineral fertilizers. However, some technologies decrease the N and P recovery and/or decrease the availability of the N and P in manure products to plants.

Implementation of manure treatment in practice is forced by the pressure from EU environmental regulations, and is hindered by financial barriers. To encourage the adoption of manure treatment, policies must be economically appealing to attract new adopters (farmers and industries). Long-term financial support schemes (e.g. subsidies) seem to be necessary, especially with the current low prices for fossil fuels. Outreach strategies are required to convey the knowledge to stakeholders from both the supply and the demand side, with respect to the economic, technical and environmental aspects of manure treatment technologies.

Rekenregels van de KringloopWijzer : achtergronden van BEX, BEA, BEN, BEP en BEC: actualisatie van de 4 maart 2014 versie
Schroder, J.J. ; Šebek, L.B. ; Reijs, J.W. ; Oenema, J. ; Goselink, R.M.A. ; Conijn, J.G. ; Boer, J. - \ 2016
Wageningen UR (PRI-rapport 640) - 103 p.
dierhouderij - duurzame veehouderij - melkproducerende dieren - melkveehouderij - landbouw - mestbeleid - modules - berekening - dierlijke meststoffen - excretie - emissiereductie - nutriëntengebruiksefficiëntie - kringlopen - animal husbandry - sustainable animal husbandry - milk yielding animals - dairy farming - agriculture - manure policy - calculation - animal manures - excretion - emission reduction - nutrient use efficiency - cycling
Bijgaand rapport beschrijft de rekenregels van de KringloopWijzer. De KringloopWijzer is een model waarmee agrarische ondernemers op basis van hun eigen bedrijfsgegevens een schatting kunnen maken van de benutting van aangevoerde nutriënten, met name stikstof (N) en fosfor (P), en van de omvang en aard van verliezen aan N, P en koolstof (C). Die schatters kunnen gebruikt worden voor het benoemen van verbeterpunten binnen het bedrijf en als verantwoording naar overheden en verwerkers. Voor de overheid biedt de KringloopWijzer mogelijkheden om generieke wetgeving te vervangen door maatwerk. Voor de verwerkende industrie is het bovendien mogelijk om het streven naar duurzaamheid meetbaar te maken ten behoeve van consumenten. De hier beschreven rapportversie bevat een aantal verbeteringen en aanvullingen ten opzichte van de versie uit 2014. Ze heeft bovendien niet langer betrekking op alleen melkvee en ruwvoergewassen, maar is ook geschikt voor bedrijven met een neventak akkerbouw en/of een neventak hokdieren. De rekenregels zijn waar mogelijk voorzien van onderbouwende referenties. Aan een verdere toetsing van deze rekenregels wordt nog voortdurend onderzoek verricht.
De P-benutting door het vee van melkveebedrijven, de impact van minimumwaarden en een tool voor verbetering
Oenema, J. ; Aarts, H.F.M. - \ 2015
Plant Research International (PRI) (PRI Rapport ) - 25 p.
cattle - dairy cattle - cattle feeding - phosphate - excretion - use efficiency - nutrient use efficiency - efficiency - feed conversion efficiency - rundvee - melkvee - rundveevoeding - fosfaat - excretie - gebruiksefficiëntie - nutriëntengebruiksefficiëntie - efficiëntie - voederconversievermogen
In 2013 was de P(benutting van de Nederlandse melkveestapel gemiddeld 30%. De benutting neemt de laatste twee decennia toe met ongeveer 0.25 procentpunt per jaar, met name door het beter presteren van melkkoeien en de afname van het aandeel jongvee. Om onder het plafond van 84.9 miljoen kg fosfaat(excretie te blijven zal een uitbreiding van de melkproductie met 10% gepaard moeten gaan met een verbetering van de benutting van de veestapel met 0.8 procentpunt; een uitbreiding met 20% of 30% verlangt een verbetering van respectievelijk 2.7 procentpunt en 4.5 procentpunt. Bij indeling van bedrijven in klassen, naar grondsoort en intensiteit (melk/ha), blijkt dat de 10% best scorende bedrijven een benutting realiseren die 5.4 tot 7.6 procentpunt hoger is dan die van de 10% slechts scorende. Als de 10%, 20% of 30% slechts scorende bedrijven gedwongen worden de minimum prestatie te realiseren van de resterende 90%, 80% of 70% leidt dit per stap tot een verbetering van 0.2 procentpunt; bij 30% dus tot 0.6 procentpunt. Besproken wordt de opzet van een tool waarmee de veehouder wordt geholpen de P(benutting te verbeteren.
Forfaitaire waarden met betrekking tot de veestapel in relatie tot de KringloopWijzer
Aarts, H.F.M. ; Sebek, L.B. - \ 2015
Wageningen : Plant Research International (PRI-rapport 636) - 17 p.
melkproductie - melkveehouderij - mestbeleid - modellen - berekening - dierlijke meststoffen - rundveemest - excretie - stikstof - fosfaat - ammoniakemissie - rundveevoeding - voederconversievermogen - milk production - dairy farming - manure policy - models - calculation - animal manures - cattle manure - excretion - nitrogen - phosphate - ammonia emission - cattle feeding - feed conversion efficiency
Het rekenmodel KringloopWijzer brengt op jaarbasis de waarden van een aantal kengetallen van het melkveebedrijf in beeld. Aan de veestapel gerelateerde kengetallen zijn 1) de excretie van stikstof (N) en fosfaat (P2O5) ‘onder de staart’, 2) de hoeveelheden N en P2O5 als voer geconsumeerd, 3) de efficiëntie waarmee de in het voer aanwezige N en P2O5 wordt omgezet in melk en groei en 4) de emissie van ammoniak (NH3) uit mest. De waarden van deze kengetallen kunnen vergeleken worden met referentie- en forfaitaire waarden. Referentiewaarden zijn waarden die door bedrijven gerealiseerd worden die in vergelijkbare omstandigheden verkeren wat betreft grondsoort en intensiteit (melkproductie per hectare). De veehouder weet daardoor hoe hij scoort in vergelijking met collega’s. Deze notitie gaat enkel in op de forfaitaire waarden voor de eerder genoemde kengetallen.
Stikstof- en fosfaatexcretie van gangbaar en biologisch gehouden landbouwhuisdieren : herziening excretieforfaits Meststoffenwet 2015
Groenestein, C.M. ; Wit, J. ; Bruggen, C. van; Oenema, O. - \ 2015
Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 45) - 48
dierlijke meststoffen - koeien - varkens - pluimvee - dierhouderij - biologische landbouw - excretie - animal manures - cows - pigs - poultry - animal husbandry - organic farming - excretion
Om de hoeveelheden stikstof en fosfaat in dierlijke mest te berekenen die op een bedrijf worden geproduceerd, kunnen veehouders gebruik maken van de zogenoemde excretieforfaits in de Uitvoeringsregeling van de Meststoffenwet. Deze excretieforfaits geven weer hoeveel stikstof en fosfaat in mest per dier en per diercategorie op jaarbasis wordt geproduceerd. Op verzoek van het Ministerie van Economische Zaken heeft de Commissie Deskundigen Meststoffenwet (CDM) een voorstel gemaakt voor herziening van de diercategorieën en de excretieforfaits van de Uitvoeringsregeling Meststoffenwet. Dit rapport beschrijft het voorstel voor de herziening van de excretieforfaits voor de eerder aangepaste lijst van diercategorieën. Bij de excretieforfaits wordt onderscheid gemaakt tussen gangbare en biologische dierhouderijsystemen. De bruto stikstof- en fosfaatexcreties voor dieren in gangbare dierhouderijsystemen zijn gebaseerd op de resultaten van de Werkgroep Uniformering berekening Mest- en mineralencijfers (WUM) voor de jaren 2011, 2012 en 2013. De WUM berekent per jaar de gemiddelde excreties per diercategorie op basis van statistieken over veevoergebruik en dierlijke productie. De bruto stikstof- en fosfaatexcreties voor dieren in biologische dierhouderijsystemen zijn gebaseerd op die van gangbare dierhouderijsystemen en een diercategorie-specifieke correctiefactor. De bruto stikstofexcreties zijn vervolgens gecorrigeerd voor gasvormige stikstofverliezen op basis van gegevens van de werkgroep National Emission Model for Agriculture (NEMA).
The iodized salt programme in Bangalore, India provides adequate iodine intakes in pregnant women and more-than-adequate iodine intakes in their children
Jaiswal, N. ; Boonstra, A. ; Sharma, S.K. ; Srinivasan, K. ; Zimmerman, M.B. - \ 2015
Public Health Nutrition 18 (2015)3. - ISSN 1368-9800 - p. 403 - 413.
school-aged children - urinary iodine - dietary iodine - deficiency - iodization - fortification - excretion - bread - nutrition - rajasthan
Objective To compare the iodine status of pregnant women and their children who were sharing all meals in Bangalore, India. Design A cross-sectional study evaluating demographic characteristics, household salt iodine concentration and salt usage patterns, urinary iodine concentrations (UIC) in women and children, and maternal thyroid volume (ultrasound). Setting Antenatal clinic of an urban tertiary-care hospital, which serves a low-income population. Subjects Healthy pregnant women in all trimesters, aged 18–35 years, who had healthy children aged 3–15 years. Results Median (range) iodine concentrations of household powdered and crystal salt were 55·9 (17·2–65·9) ppm and 18·9 (2·2–68·2) ppm, respectively. The contribution of iodine-containing supplements and multi-micronutrient powders to iodine intake in the families was negligible. Adequately iodized salt, together with small amounts of iodine in local foods, were providing adequate iodine during pregnancy: (i) the overall median (range) UIC in women was 172 (5–1024) µg/l; (ii) the median UIC was >150 µg/l in all trimesters; and (iii) thyroid size was not significantly different across trimesters. At the same time, the median (range) UIC in children was 220 (10–782) µg/l, indicating more-than-adequate iodine intake at this age. Median UIC was significantly higher in children than in their mothers (P=0·008). Conclusions In this selected urban population of southern India, the iodized salt programme provides adequate iodine to women throughout pregnancy, at the expense of higher iodine intake in their children. Thus we suggest that the current cut-off for median UIC in children indicating more-than-adequate intake, recommended by the WHO/UNICEF/International Council for the Control of Iodine Deficiency Disorders may, need to be reconsidered.
Changes in Pig Production in China and Their Effects on Nitrogen and Phosphorus Use and Losses
Bai, Z.H. ; Ma, L. ; Qin, W. ; Chen, Q. ; Oenema, O. ; Zhang, F.S. - \ 2014
Environmental Science and Technology 48 (2014)21. - ISSN 0013-936X - p. 12742 - 12749.
food-chain - integrated assessment - ammonia emission - nutrient flows - agriculture - consumption - management - performance - excretion - denmark
China's pig production has increased manifold in the past 50 years, and this has greatly affected the nitrogen and phosphorus use and losses in the pig production sector. However, the magnitude of these changes are not well-known. Here, we provide an in-depth account of the changes in pig production-N and P use and total N and P losses in the whole pig production chain during the period 1960-2010-through simulation modeling and using data from national statistics and farm surveys. For the period of 2010-2030, we explored possible effects of technological and managerial measures aimed at improving the performances of pig production via scenario analysis. We used and further developed the NUtrient flows in Food Chains, Environment and Resources use (NUFER) model to calculate the feed requirement and consumption, and N and P losses in different pig production systems for all the years Between 1960 and 2010, pig production has largely shifted from the so-called backyard system to landless systems. The N use efficiencies at fattener level increased from 18 to 28%, due to the increased animal productivity. However, the N use efficiencies at the Whole system level decreased from 46 to 11% during this period, mainly due to the increase of landless pig farms, which rely on imported feed and have no land-base for manure disposal. The total N and P losses were 5289 and 829 Gg in 2010, which is 30 and 95 times higher than in 1960. In the business as usual scenario, the total N and P losses were projected to increase by 25 and 55% between 2010 and 2030, respectively. Analyses of other scenarios indicate that packages of technological and managerial measures can decrease total N and P losses by 64 and 95% respectively. Such improvements require major transition in the pig production sector, notably, in manure management, herd management, and feeding practices.
Excretieforfaits van mest: verschillen tussen berekende en gemeten N/P2O5 ratio's in mest
Groenestein, K. ; Bikker, P. ; Hoeksma, P. ; Zom, R.L.G. ; Bruggen, C. van - \ 2014
Wageningen : Wageningen UR Livestock Research (Rapport / Wageningen UR Livestock Research 748) - 36
dierlijke meststoffen - excretie - stikstof - fosfaat - mineralen - mestbeleid - chemische analyse - landbouw en milieu - veehouderij - duurzame veehouderij - emissie - animal manures - excretion - nitrogen - phosphate - minerals - manure policy - chemical analysis - agriculture and environment - livestock farming - sustainable animal husbandry - emission
It has been noted that the calculated composition of the manure based on the National Emission Model Agriculture (NEMA) differed from those measured in the samples of transported manure and registered by the Netherlands Enterprise Agency (RVO). This study analysed the data and came to identification of the factors that can cause the differences. Recommendations were then made o prevent those differences.
Estimation of the transmission of foot-and-mouth disease virus from infected sheep to cattle
Bravo De Rueda, C. ; Jong, M.C.M. de; Eble, P.L. ; Dekker, A. - \ 2014
Veterinary Research 45 (2014). - ISSN 0928-4249 - 11 p.
between-pen transmission - basic reproduction ratio - swine-fever virus - emergency vaccination - subclinical infection - within-pen - pigs - quantification - excretion - epidemic
The quantitative role of sheep in the transmission of foot-and-mouth disease virus (FMDV) is not well known. To estimate the role of sheep in the transmission of FMDV, a direct contact transmission experiment with 10 groups of animals each consisting of 2 infected lambs and 1 contact calf was performed. Secretions and excretions (oral swabs, blood, urine, faeces and probang samples) from all animals were tested for the presence of FMDV by virus isolation (VI) and/or RT-PCR. Serum was tested for the presence of antibodies against FMDV. To estimate FMDV transmission, the VI, RT-PCR and serology results were used. The partial reproduction ratio R0 p i.e. the average number of new infections caused by one infected sheep introduced into a population of susceptible cattle, was estimated using either data of the whole infection chain of the experimental epidemics (the transient state method) or the final sizes of the experimental epidemics (the final size method). Using the transient state method, R0 p was estimated as 1.0 (95% CI 0.2 - 6.0) using virus isolation results and 1.4 (95% CI 0.3 - 8.0) using RT-PCR results. Using the final size method, R0 p was estimated as 0.9 (95% CI 0.2 - 3.0). Finally, R0 p was compared to the R0’s obtained in previous transmission studies with sheep or cattle only. This comparison showed that the infectivity of sheep is lower than that of cattle and that sheep and cattle are similarly susceptible to FMD. These results indicate that in a mixed population of sheep and cattle, sheep play a more limited role in the transmission of FMDV than cattle.
The bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens
Veldkamp, T. ; Diepen, J.T.M. van; Bikker, P. - \ 2014
Wageningen : Wageningen UR Livestock Research (Report / Wageningen UR Livestock Research 806) - 27
vleeskuikens - biologische beschikbaarheid - zink - belgië - voedingsstoffenbehoeften - excretie - excreten - landbouw en milieu - pluimveevoeding - pluimveehouderij - wetenschappelijk onderzoek - broilers - bioavailability - zinc - belgium - nutrient requirements - excretion - excreta - agriculture and environment - poultry feeding - poultry farming - scientific research
Zinc is an essential trace element for all farm animal species. It is commonly included in animal diets as zinc oxide, zinc sulphate or organically bound zinc. Umicore Zinc Chemicals developed zinc oxide products with different mean particle sizes. Umicore Zinc Chemicals requested Wageningen UR Livestock Research to determine the bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens. A precise estimate of the bioavailability of zinc sources is required both for fulfilling the zinc requirements of the animal and to reduce zinc excretion in excreta and the environment.
Comparison of the degradation and leaching kinetics of glucosinolates during processing of four Brassicaceae (broccoli, red cabbage, white cabbage, Brussels sprouts)
Sarvan, I. ; Verkerk, R. ; Boekel, M.A.J.S. van; Dekker, M. - \ 2014
Innovative Food Science and Emerging Technologies 25 (2014). - ISSN 1466-8564 - p. 58 - 66.
thermal-degradation - vegetables - oleracea - isothiocyanates - cancer - myrosinase - metabolism - excretion - cooking - risk
Glucosinolates (GSs) are secondary metabolites of Brassica vegetables that are associated with health benefits. The concentrations of these compounds are strongly affected by processing of the vegetables. During thermal treatment of Brassicaceae, such as domestic cooking, different mechanisms affecting the content of GSs can take place and were modeled in the present study: Lysis of plant cells and compartments, leaching of GSs into the cooking water and thermal degradation of GSs in both the intact vegetable tissue and the cooking water. These mechanisms were described mathematically and the model parameters for broccoli, Brussels sprouts, red cabbage and white cabbage were estimated based on experimental results. Differences between the thermostability of the same GSs originating from different Brassicaceae could be detected, as well as differences between the thermostability of the same GSs in the vegetable matrix compared to that in the cooking water. Industrial relevance: This mathematical model and the estimated parameters can be used to simulate the different glucosinolate contents in prepared foods considering the processing method. This will be a very useful tool for food research and industry to make predictions about the nutritional quality of foods and to optimize their health related quality attributes.
Prediction of nitrogen use in dairy cattle: a multivariate Bayesian approach
Reed, K.F. ; Moraes, L.E. ; Fadel, J.G. ; Casper, D.P. ; Dijkstra, J. ; France, J. ; Kebreab, E. - \ 2014
Animal Production Science 54 (2014)12. - ISSN 1836-0939 - p. 1918 - 1926.
cows - excretion - protein - management - metabolism - efficiency - ruminants - pollution - dietary - manure
Quantification of dairy cattle nitrogen (N) excretion and secretion is necessary to improve the efficiency with which feed N is converted to milk N (ENU). Faecal and urinary N excretion and milk N secretion are correlated with each other and thus are more accurately described by a multivariate model that can accommodate the covariance between the three observations than by three separate univariate models. Further, by simultaneously predicting the three routes of excretion and taking advantage of the mass balance relationships between them, covariate effects on N partitioning from feed to faeces and absorbed N and from absorbed N to milk and urine N and animal ENU can be estimated. A database containing 1094 lactating dairy cow observations collated from indirect calorimetry experiments was used for model development. Dietary metabolisable energy content (ME, MJ/kg DM) increased ENU at a decreasing rate, increased the efficiency with which feed N was converted to absorbed N and decreased the efficiency with which absorbed N was converted to milk N. However, the parameter estimate of the effect of ME on post-absorption efficiency was not different from zero when the model was fitted to a data subset in which net energy and metabolisable protein were at or above requirement. This suggests the effect of ME on post-absorption N use is dependent on the energy status of the animal.
In vivo formation and bioavailability of isothiocyanates from glucosinolates in broccoli as affected by processing conditions
Oliviero, T. ; Verkerk, R. ; Vermeulen, M. ; Dekker, M. - \ 2014
Molecular Nutrition & Food Research 58 (2014)7. - ISSN 1613-4125 - p. 1447 - 1456.
brassica vegetables - cruciferous vegetables - myrosinase activity - human health - red cabbage - sulforaphane - excretion - l. - degradation - consumption
Scope: To study the effect of residual myrosinase (MYR) activity in differently processed broccoli on sulforaphane (SR) and iberin (IB) formation, bioavailability, and excretion in human volunteers. Methods and results: Five different broccoli products were obtainedwith similar glucoraphanin (GR) and glucoiberin (GI) content, yet different MYR activity. Excretion of SR and IB conjugates in urine were determined in 15 participants after ingestion of the broccoli products. A reduction of 80% of MYR in the product did not cause differences in the total amount of SR and IB found in urine compared to the product with 100% MYR. Complete inactivation of MYR gave the lowest total amount of SR and IB in urine (10 and 19%). A residual MYR of only 2% in the product gave an intermediate amount (17 and 29%). The excretion half-lives of SR and IB conjugates were comparable for all the products (2.5 h on average), although the maximum excretion peak times were clearly shorter when the residual MYR was higher (2.3–6.1 h). Conclusion: For the first time, the effect of residual MYR activity on isothiocyanate bioavailability was systematically and quantitatively studied. Processing conditions have a large effect on the kinetics and bioavailability of isothiocyanates from broccoli.
Amazing Grazing deelproject: De Weidewasser 2013 : innovatievraag: Hogere opbrengst en lagere verliezen van grasland? : opgave: Negatief effect van mestflatten omzetten in positief effect
Schooten, H.A. van; Houwelingen, K.M. van; Philipsen, A.P. ; Eekeren, N.J.M. van; Lenssinck, F.A.J. - \ 2014
Lelystad : Wageningen UR Livestock Research - 19
rundveehouderij - excretie - dierlijke meststoffen - graslanden - begrazing - graslandbeheer - bevochtigingsapparatuur - spuitapparaten - innovaties - cattle husbandry - excretion - animal manures - grasslands - grazing - grassland management - humidifiers - sprayers - innovations
Mestflatten in de wei als gevolg van beweiding geven veel beweidingsverliezen en een slechte benutting van de mest. De mestflatten goed verspreiden en vervolgens naspoelen met water is mogelijk een oplossing. Op basis van deze gedachte is vanuit Amazing Grazing op proefbedrijf Zegveld de zogenaamde weidewasser ontwikkeld. Met deze weidewasser en een aantal andere machines, waarmee mestflatten kunnen worden verspreid, is een oriënterende proef opgezet. Het doel hiervan was om meer inzicht te krijgen in afbraak van mestflatten en benutting van gras bij verspreiding van mestflatten met de weidewasser ten opzichte van verspreiding van mestflatten met een aantal bestaande machines. Dit onderzoeksverslag beschrijft de uitvoering en ervaringen van het eerste oriëntatie jaar 2013 met de weidewasser en met een aantal verschillende sleeptechnieken.
BEX bespaart gemiddeld Koeien & Kansen-bedrijf 566 ton mestafvoer in 2013
Evers, A.G. ; Haan, M.H.A. de - \ 2014
Koeien & Kansen
melkveehouderij - excretie - dierlijke meststoffen - stikstof - emissiereductie - fosfaten - monitoring - mestbeleid - dairy farming - excretion - animal manures - nitrogen - emission reduction - phosphates - manure policy
Toelichting op de voordelen van het gebruik van de Excretiewijzer, die de excretie van stikstof en fosfaat berekent (BEX), bij 16 Koeien en Kansenbedrijven.
Variation in phosphorus content of milk from dairy cattle as affected by differences in milk composition
Klop, G. ; Ellis, J.L. ; Blok, M.C. ; Brandsma, G.G. ; Bannink, A. ; Dijkstra, J. - \ 2014
The Journal of Agricultural Science 152 (2014)5. - ISSN 0021-8596 - p. 860 - 869.
environmental-impact - methane production - blood-plasma - beef-cattle - cows - excretion - prediction - magnesium - calcium
In view of environmental concerns with regard to phosphorus (P) pollution and the expected global P scarcity, there is increasing interest in improving P utilization in dairy cattle. In high-producing dairy cows, P requirements for milk production comprise a significant fraction of total dietary P requirements. Although variation in P content of milk can affect the efficiency of P utilization for milk production (i.e. the fraction of ingested P that is incorporated in milk), this variation is poorly understood. It was hypothesized that the P content of milk is related to both milk protein and milk lactose content, but not necessarily to milk fat content. Three existing experiments comprising individual animal data on milk yield and fat, protein, lactose and P content of milk (in total 278 observations from 121 cows) were analysed to evaluate this hypothesis using a mixed model analysis. The models including the effects of both protein and lactose content of milk yielded better prediction of milk P content in terms of root-mean-square prediction error (RMSPE) and concordance correlation coefficient (CCC) statistics than models with only protein included as prediction variable; however, estimates of effect sizes varied between studies. The inclusion of milk fat content in equations already including protein and lactose did not further improve prediction of milk P content. Equations developed to describe the relationship between milk protein and lactose contents (g/kg) and milk P content (g/kg) were: (Expt 1) P in milk=-0·44(±0·179)+0·0253(±0·00300)×milk protein+0·0133(±0·00382)×milk lactose (RMSPE: 5·2%; CCC: 0·71); (Expt 2) P in milk=-0·26 (±0·347)+0·0174(±0·00328)×milk protein+0·0143 (±0·00611)×milk lactose (RMSPE: 6·3%; CCC: 0·40); and (Expt 3) P in milk=-0·36(±0·255)+0·0131(±0·00230)×milk protein+0·0193(±0·00490)×milk lactose (RMSPE: 6·5%; CCC: 0·55). Analysis of the three experiments combined, treating study as a random effect, resulted in the following equation to describe the same relationship as in the individual study equations: P in milk=-0·64(±0·168)+0·0223(±0·00236)×milk protein+0·0191(±0·00316)×milk lactose (RMSPE: 6·2%; CCC: 0·61). Although significant relationships between milk protein, milk lactose and milk P were found, a considerable portion of the observed variation remained unexplained, implying that factors other than milk composition may affect the P content of milk. The equations developed may be used to replace current fixed milk P contents assumed in P requirement systems for cattle.
Rekenregels van de KringloopWijzer : achtergronden van BEX, BEA, BEP en BEC
Schroder, J.J. ; Sebek, L.B. ; Reijs, J.W. ; Oenema, J. ; Goselink, R.M.A. ; Conijn, J.G. ; Boer, J.M. de - \ 2014
Wageningen : Plant Research International, Business Unit Agrosysteemkunde (Rapport / Plant Research International 553) - 88
melkveehouderij - excretie - dierlijke meststoffen - emissiereductie - bemesting - kringlopen - gebruiksefficiëntie - modules - mestbeleid - dairy farming - excretion - animal manures - emission reduction - fertilizer application - cycling - use efficiency - manure policy
Het project KringloopWijzer (KLW) heeft tot doel een instrument te ontwikkelen, te toetsen en de introduceren, die de kringloop en de verliezen van N, P en C wetenschappelijk, integraal, eenduidig en betrouwbaar in beeld brengt. De KringloopWijzer is een modulair systeem en dit rapport behandelt achtereenvolgens de volgende modules: BEX (Bedrijfsspecifieke excretie), de BEA (Bedrijfsspecifieke emissie van ammoniak), de BEN (Bedrijfsspecifieke emissie van nitraat en lachgas), de BEP (Bedrijfsspecifieke fosfaatstromen) en de BEC (Bedrijfsspecifieke koolstofstromen). Samen vormen deze de complete Kringloopwijzer, die benuttingpercentages in kaart brengt op zowel systeemniveau als op niveau van de onderdelen van de bedrijfsvoering.
Improvement of energy and nitrogen utilisation in pork production : genetics and growth models
Shirali, M. - \ 2014
University. Promotor(en): R. Roehe; Johan van Arendonk, co-promotor(en): Egbert Kanis. - Wageningen : Wageningen University - ISBN 9789461738479 - 186
dierveredeling - varkens - dierlijke productie - groeimodellen - genetica - stikstof - excretie - voederconversievermogen - animal breeding - pigs - animal production - growth models - genetics - nitrogen - excretion - feed conversion efficiency

Expansion ofdemand for porkis expected to meet the nutritional requirements of an increasing world population. However, higher levels of pig production are using limited feed resources and are often associated with higher levels of environmental pollution, which provide substantial challenges for pork producers. Therefore, strategies that simultaneously improve feed efficiency and increase production with reduction of environmental pollution of pork production (e.g. per kg product) is necessary. The general aim of the current project was to investigate opportunities for improvement of energy usage and nitrogen excretion at different stages of growth in pigs, and to determine their phenotypic and genetic background in association with other performance traits as well as to provide the basis for developing strategies for improvement of these traits using biological growth models.Feed efficiency was characterised by residual energy intake (REI) as the surplus of energy intake which is not used for protein and lipid deposition along with maintenance throughout growth to 140 kg BW whereas nitrogen excretion was estimated as the difference between nitrogen intake and retention. The results of phenotypic analyses indicate that nitrogen excretion increases substantially during growth of pigs and can be reduced most effectively by improving feed efficiency and to a lesser extent through the improvement of weight gain and/or body composition. Results of genetic analyses indicate that REI as a measure of feed efficiency is highly heritable (h2= 0.44), suggesting great potential for genetic improvement. REI has different genetic background at different stages of growth, suggesting that genetic improvement of REI should consider the stage of growth. In addition, REI explains a large portion of variance in nitrogen excretion, suggesting that selection for lower REI is expected to reduce nitrogen excretion of pork production as well as improve feed efficiency. Genomic analysis showed that different genes are responsible for efficiency of feed utilisation at different stages of growth.The results further suggest that only a small proportion of the variance in REI was explained by variation in feed intake, whereas underlying factors of feed utilisation, such as metabolism and protein turnover, are likely to have great influence on REI. A biological growth model was used to characterize a crossbred population regarding feed energy and nitrogen efficiency in comparison to two purebred population selected for different performances. The results of the biological growth model can be used to developed optimal genetic, nutritional and production strategies, e.g. the impact of reduction in slaughter weight on marginal energy efficiency and nitrogen excretion was estimated. Furthermore, based on the results of the biological growth model, the influence of changes of production traits during growth on energy and nitrogen efficiency can be estimated to optimise genetic strategies. Furthermore, opportunities for further improvement of energy and nitrogen utilisation have been outlined.

Feed-milk-manure nitrogen relationships in global dairy production systems
Powell, J.M. ; Macleod, M. ; Vellinga, Th.V. ; Opio, C. ; Falcucci, A. ; Tempio, G. ; Steinfeld, H. ; Gerber, P. - \ 2013
Livestock Science 152 (2013)2-3. - ISSN 1871-1413 - p. 261 - 272.
dietary-protein - nutrient management - use efficiency - urea nitrogen - farms - cows - excretion - cycle - performance - emissions
Nitrogen (N) inputs from fertilizer, biologically-fixed N, feed, and animal manure sustain productive agriculture. Agricultural systems are limited however in their ability to incorporate N into products, and environmental N losses may become local, regional and global concerns. The anticipated increases in global demand for food, especially for animal products, necessitate an urgent search for practices that enhance N use efficiency (NUE) and reduce environmental N loss. The objectives of this study were to determine feed-milk-manure N relationships for the global dairy herd, and to evaluate how well regional and production system determinations of these relationships correspond to measurements made under experimental conditions and on commercial dairy farms. Data on dairy cattle populations, feed and milk production from 142 countries were used in a Life Cycle Assessment (LCA) model to determine dry matter intake (DMI), N intake (NI), the percentage of NI secreted as milk N (NUE-milk), the percent of NI used by the whole-herd (NUE-herd), and manure N excretion (Nex). On a global basis, an average lactating cow weighs approximately 420 kg; per animal unit (AU = 1000 kg live weight) daily DMI and NI are 21.0 kg and 477 g, respectively; annual milk production is 5000 kg/AU; and NUE-milk and NUE-herd are 16.0% and 15.6%, respectively. Approximately 37% of global lactating cows have NUE-milk of <10% and these low efficient cows account for 10% of the milk production and 33% of Nex globally. Approximately 30% of global lactating cows have NUE-milk between 21% and 25% and these cows account for 53% of the milk production and 35% of Nex globally. Estimates of NUE-milk and Nex corresponded well to measurements under experimental and commercial farm conditions. Study determinations of Nex were however 3-50% lower than IPCC Tier 1 values of Nex for Africa, Middle East, Latin America and Asia. The apparent accuracy of LCA model calculations of Nex should enhance regional, production system and global determinations of dairy Nex loss during collection, storage, and land application, and the amounts of Nex actually recycled through crops and pastures. Published by Elsevier B.V.
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