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De Topro Dry bolus biedt een langdurige afgifte (60 dagen) van sporenelementen en vitamines aan vee. In samenwerking met Van Hall Larenstein is er onderzoek gedaan naar de vreet- en herkauwactiviteit van melkkoeien. De resultaten staan in deze whitepaper. Het onderzoek is uitgevoerd door Simone Oudenampsen, studente Dier- en Veehouderij aan hogeschool Van Hall Larenstein in Leeuwarden.

De Topro Dry bolus biedt een langdurige afgifte (60 dagen) van sporenelementen en vitamines aan vee. In samenwerking met Van Hall Larenstein is er onderzoek gedaan naar de vreet- en herkauwactiviteit van melkkoeien. De resultaten staan in deze whitepaper. Het onderzoek is uitgevoerd door Simone Oudenampsen, studente Dier- en Veehouderij aan hogeschool Van Hall Larenstein in Leeuwarden.

In het voorjaar van 2021 is er praktijkonderzoek uitgevoerd naar het effect van extra mineralen en vitamines in de droogstandsperiode door middel van de Topro Dry bolus. Deze bolus werd ingebracht bij het droogzetten en geeft over een periode van 60 dagen sporenelementen en vitamines af aan de koe en aan het ongeboren kalf. Dit praktijkonderzoek is uitgevoerd door een student van Van Hall Larenstein University of Applied Sciences in Leeuwarden.

De industrie heeft een veelheid aan supplementen ontwikkeld die specifiek voor ouderen zijn. Sommige van deze supplementen bevatten hoge doseringen van bepaalde vitaminen en mineralen. Deze doseringen blijven onder de 'maximaal aanvaardbare bovengrens' (Upper Limit), en zijn meestal niet hoger dan drie keer de aanbevolen dagelijkse hoeveelheid (ADH). Uit onderzoek van het RIVM blijkt dat deze supplementen niet schadelijk zijn voor de gezondheid. Verder zijn er in supplementen voor ouderen hoge doseringen gevonden van stoffen waarvoor geen UL bestaat: B-vitamines, vitamine C en ijzer. Daardoor kunnen voor deze stoffen geen conclusies worden getrokken over de veiligheid van de doseringen. In algemene zin is daarom voorzichtigheid geboden als deze producten langere tijd worden gebruikt. Er zijn algemene supplementen op de markt, niet specifiek gericht op ouderen, die een dosering bevatten boven de Upper Limit. Ook ouderen kunnen deze producten gebruiken. Het gaat om bepaalde preparaten die hoge gehalten bevatten van de vitaminen foliumzuur, B6, D en E, en de mineralen zink en selenium. Het is niet uitgesloten dat een te hoge inname van de vitaminen B6 en E op de lange termijn schadelijk kan zijn voor de gezondheid en het welzijn van ouderen. Te hoge doseringen van vitamine B6 kan neurologische klachten veroorzaken, het gebruik van te veel vitamine E kan bloedstollingen veroorzaken. Samenvattend, supplementen die specifiek voor ouderen ontwikkeld zijn, kunnen beschouwd worden als niet gevaarlijk. Er zijn echter een aantal producten verkrijgbaar die niet specifiek op ouderen gericht zijn maar die wel door ouderen gebruikt kunnen worden, die de Upper Limit van toxiciteit overschrijden. Dagelijks gebruik van deze producten gedurende langere perioden is mogelijk schadelijk voor de gezondheid van ouderen. Voor dit onderzoek zijn alle supplementen die ouderen kunnen gebruiken geïnventariseerd.

Het is van belang om de werkelijke beschikbaarheid van bepaalde vitaminen en mineralen in het lichaam (de voorziening) van de Nederlandse bevolking vast te stellen. Dit kan aan de hand van onderzoek in bloed en urine, ook wel voedingsstatusonderzoek genoemd. Momenteel wordt de inneming van vitaminen en mineralen bepaald door middel van voedselconsumptiepeilingen. Hierbij wordt gewerkt met de navraag van de voedselconsumptie. Met behulp van voedingsstatusonderzoek kunnen signalen uit de voedselconsumptiepeiling van een mogelijk te lage inneming (vitamine B2, foliumzuur, vitamine B12, vitamine D, magnesium, ijzer, zink) of te hoge inneming (vitamine D, natrium, zink) worden getoetst. Voor enkele mineralen kan de inneming niet goed worden bepaald, dit is het geval voor jodium, natrium en seleen. Met statusonderzoek kan wel de beschikbaarheid in het lichaam worden bepaald voor deze mineralen. Voor allochtone bevolkingsgroepen wordt om praktische redenen aanbevolen om statusonderzoek uit te voeren voorafgaand aan voedselconsumptieonderzoek. De te bepalen parameters voor de vitaminen B2, B12, D en foliumzuur en voor de mineralen magnesium, natrium, ijzer, jodium, seleen en zink worden in het rapport besproken. Ook voor vitamine A, calcium en chroom zou voedingsstatusonderzoek gewenst zijn; echter voor deze voedingstoffen zijn momenteel geen goede parameters beschikbaar.

In de biologische geitenhouderij is weidegang verplicht en bevat het rantsoen ook in de stalperiode meer ruwvoer dan in de gangbare geitenhouderij. Ook wordt soms eigen graan gevoerd ter vervanging van commercieel krachtvoer. De voorziening met mineralen, spoorelementen en vitaminen moet daarbij bewuster gestuurd worden. Binnen het project Biogeit is op veertien biologische geitenbedrijven bloed onderzocht op gehalten aan mineralen en vitaminen. Ook is gekeken naar de gehalten in het rantsoen. In dit artikel staat zink centraal

In een Spelderholt-proef is gekeken naar mogelijkheden om via voermaatregelen het optreden van pootproblemen bij Peking-eenden te verminderen. Deze maatregelen betroffen de verschijningsvorm, beschikbaarheid en samenstelling van het voer. Tevens is het effect van deze aanpassingen op technische resultaten en slachtrendementen onderzocht.

The aim of this thesis was to evaluate micronutrient intake and status of socioeconomic disadvantaged populations, such as from Central and Eastern European (CEE) as compared to other European populations, and low socioeconomic status (SES) groups as compared to high SES groups within European countries. We addressed the micronutrients that have been prioritized because of their relevance for nutritional health by the EC-funded EURRECA Network of Excellence. Moreover, we assessed the association between folate intake and status which can be used in the process of setting folate DRVs. Micronutrient intake and status of CEE countries versus other European countries CEE countries have recently experienced rising income inequalities over a period of economic transition. There is some evidence that these reforms have been accompanied by health inequalities. Inadequacy in micronutrient intake and status may contribute to these inequalities. Because in more affluent Western European countries wide ranges in micronutrient intake and status are observed, we studied if low micronutrient intake and status levels are prevailing in CEE. The findings from this thesis signal no differences in micronutrient intake and status between CEE populations in comparison to those of other European regions with the exception of calcium intake in adults and iodine status in children that were lower in CEE than in other European regions. Since data from Western Europe indicate that inadequacies do exist among SES strata, more insight in the nutritional situation of lower SES populations in CEE and an understanding of both its determinants and consequences is needed. It is important to mention that evidence from grey literature added to that from open access sources. Fundamental to further studying of nutritional health in CEE, is suitable data. We underline the necessity for conducting nutritional surveillances on micronutrient intake and status in CEE as we have identified significant knowledge gaps for many life-stage groups. Differences in micronutrient intake between SES groups Considering that not enough studies have addressed the relationship between SES and micronutrient intake and status in their analyses of nutritional health, we performed a systematic review on this topic and we used data from the large European EPIC cohort to address that issue. To be able to conclude on socioeconomic, i.e. educational, occupational and income, inequalities associated with intake and status of prioritized micronutrients for all life stages in Europe, substantial knowledge gaps should be filled. Currently, data are mostly available for the intake of calcium, vitamin C and iron as collected from adults in Western European countries. When either of the above mentioned SES indicators was applied to estimate relative differences in micronutrient intake and status between the lowest and the highest SES category within one study, the results often, but not consistently, indicated a lower intake and/or status in low versus high SES groups. For example, in eight out of ten studies a lower intake for calcium intake was found with relative differences ranging from -2 to -14%. Similar patterns were found for vitamin C and iron: in eleven out of twelve studies relative differences ranged from -5 to -48% for vitamin C, whereas in nine of ten studies on iron relative differences went up to -14%. Studies on intake and/or status of folate, vitamin B12, zinc, iodine, and intake of vitamin D, selenium and copper were limited. Still, when differences were observed, it appeared that lower intake in low than in high SES groups was found except for vitamin B12 and zinc for which the findings were inconsistent. Furthermore, using education as a proxy for SES, we assessed differences in micronutrient intake between educational levels using the individual-participant data on European adults and elderly from the EPIC cohort. Based on data from 10 Western European countries it appeared that intake of calcium (except in France and a distinctive ‘health-conscious’ group in the UK), folate (except in Greece), and vitamin C was lower in the lowest than in the highest education groups: relative differences ranged up to 12, 13 and 23%, respectively. The intake of iron differed marginally, whereas the variation in intake of vitamins D and B12 was inconsistent. The observed association between educational level and intake of micronutrients was the same for men and women. Furthermore, differences in micronutrient intake were found to be larger between countries than between SES groups. With respect to SES differences in micronutrient intake and status, there are significant gaps in the open source literature for many life-stage groups in Europe, but particularly in CEE countries. There is a clear need for cross-country and within country comparative research and for the monitoring of trends in dietary intake across different SES groups and European countries. Relationship between folate intake and status to add complementary evidence for deriving folate dietary reference values (DRVs) DRVs are under continuous review and periodic revision as the cumulative evidence base and body of knowledge evolve. Folate is considered a public health priority micronutrient for which re-evaluation of DRVs is needed. For this micronutrient, a systematic review of observational studies on the relationship between intake and status was done followed by meta-analysis. The intake of folate was significantly associated with markers of folate status. The results of our meta-analysis showed that an average person with a folate intake of 100 µg/day has a serum/plasma folate status concentration that is 26% higher and a red blood cell folate status that is 21% higher than a person who has a folate intake of 50 µg/day; plasma homocysteine was found to be 16% lower. The difference between natural food folate and that from supplements and fortified foods (folic acid) significantly influenced the estimated relationship between folate intake and serum/plasma status. Associations were stronger when assessed as folate from the diet than as folate from diet and supplements. Dietary assessment method did not significantly influence the association, although pooled estimates were somewhat higher when FFQs were used as compared to 24-hour recalls combined with food records. To focus on the impact of poor intakes on related health outcomes, data modelling can be conducted to produce estimates for Average Nutrient Requirements. For this analysis datasets and statistical models developed within the EURRECA NoE are available and can be used. Overall, further research would benefit from methodologically comparable data on food intake in all age ranges, especially on so far understudied CEE populations. Both intakes obtained through diet and from supplements and fortified foods should be assessed. Monitoring of trends across SES strata should be done with standardized SES measurements that would also facilitate cross-country comparative research. The findings on the level and distribution of micronutrient intake and status could be used for development of food based dietary guidelines. To make them effective in meeting populations’ micronutrient needs, they should be created accounting for the country specific dietary patterns giving consideration to the socioeconomic context.

The aim of this thesis was to evaluate micronutrient intake and status of socioeconomic disadvantaged populations, such as from Central and Eastern European (CEE) as compared to other European populations, and low socioeconomic status (SES) groups as compared to high SES groups within European countries. We addressed the micronutrients that have been prioritized because of their relevance for nutritional health by the EC-funded EURRECA Network of Excellence. Moreover, we assessed the association between folate intake and status which can be used in the process of setting folate DRVs. Micronutrient intake and status of CEE countries versus other European countries CEE countries have recently experienced rising income inequalities over a period of economic transition. There is some evidence that these reforms have been accompanied by health inequalities. Inadequacy in micronutrient intake and status may contribute to these inequalities. Because in more affluent Western European countries wide ranges in micronutrient intake and status are observed, we studied if low micronutrient intake and status levels are prevailing in CEE. The findings from this thesis signal no differences in micronutrient intake and status between CEE populations in comparison to those of other European regions with the exception of calcium intake in adults and iodine status in children that were lower in CEE than in other European regions. Since data from Western Europe indicate that inadequacies do exist among SES strata, more insight in the nutritional situation of lower SES populations in CEE and an understanding of both its determinants and consequences is needed. It is important to mention that evidence from grey literature added to that from open access sources. Fundamental to further studying of nutritional health in CEE, is suitable data. We underline the necessity for conducting nutritional surveillances on micronutrient intake and status in CEE as we have identified significant knowledge gaps for many life-stage groups. Differences in micronutrient intake between SES groups Considering that not enough studies have addressed the relationship between SES and micronutrient intake and status in their analyses of nutritional health, we performed a systematic review on this topic and we used data from the large European EPIC cohort to address that issue. To be able to conclude on socioeconomic, i.e. educational, occupational and income, inequalities associated with intake and status of prioritized micronutrients for all life stages in Europe, substantial knowledge gaps should be filled. Currently, data are mostly available for the intake of calcium, vitamin C and iron as collected from adults in Western European countries. When either of the above mentioned SES indicators was applied to estimate relative differences in micronutrient intake and status between the lowest and the highest SES category within one study, the results often, but not consistently, indicated a lower intake and/or status in low versus high SES groups. For example, in eight out of ten studies a lower intake for calcium intake was found with relative differences ranging from -2 to -14%. Similar patterns were found for vitamin C and iron: in eleven out of twelve studies relative differences ranged from -5 to -48% for vitamin C, whereas in nine of ten studies on iron relative differences went up to -14%. Studies on intake and/or status of folate, vitamin B12, zinc, iodine, and intake of vitamin D, selenium and copper were limited. Still, when differences were observed, it appeared that lower intake in low than in high SES groups was found except for vitamin B12 and zinc for which the findings were inconsistent. Furthermore, using education as a proxy for SES, we assessed differences in micronutrient intake between educational levels using the individual-participant data on European adults and elderly from the EPIC cohort. Based on data from 10 Western European countries it appeared that intake of calcium (except in France and a distinctive ‘health-conscious’ group in the UK), folate (except in Greece), and vitamin C was lower in the lowest than in the highest education groups: relative differences ranged up to 12, 13 and 23%, respectively. The intake of iron differed marginally, whereas the variation in intake of vitamins D and B12 was inconsistent. The observed association between educational level and intake of micronutrients was the same for men and women. Furthermore, differences in micronutrient intake were found to be larger between countries than between SES groups. With respect to SES differences in micronutrient intake and status, there are significant gaps in the open source literature for many life-stage groups in Europe, but particularly in CEE countries. There is a clear need for cross-country and within country comparative research and for the monitoring of trends in dietary intake across different SES groups and European countries. Relationship between folate intake and status to add complementary evidence for deriving folate dietary reference values (DRVs) DRVs are under continuous review and periodic revision as the cumulative evidence base and body of knowledge evolve. Folate is considered a public health priority micronutrient for which re-evaluation of DRVs is needed. For this micronutrient, a systematic review of observational studies on the relationship between intake and status was done followed by meta-analysis. The intake of folate was significantly associated with markers of folate status. The results of our meta-analysis showed that an average person with a folate intake of 100 µg/day has a serum/plasma folate status concentration that is 26% higher and a red blood cell folate status that is 21% higher than a person who has a folate intake of 50 µg/day; plasma homocysteine was found to be 16% lower. The difference between natural food folate and that from supplements and fortified foods (folic acid) significantly influenced the estimated relationship between folate intake and serum/plasma status. Associations were stronger when assessed as folate from the diet than as folate from diet and supplements. Dietary assessment method did not significantly influence the association, although pooled estimates were somewhat higher when FFQs were used as compared to 24-hour recalls combined with food records. To focus on the impact of poor intakes on related health outcomes, data modelling can be conducted to produce estimates for Average Nutrient Requirements. For this analysis datasets and statistical models developed within the EURRECA NoE are available and can be used. Overall, further research would benefit from methodologically comparable data on food intake in all age ranges, especially on so far understudied CEE populations. Both intakes obtained through diet and from supplements and fortified foods should be assessed. Monitoring of trends across SES strata should be done with standardized SES measurements that would also facilitate cross-country comparative research. The findings on the level and distribution of micronutrient intake and status could be used for development of food based dietary guidelines. To make them effective in meeting populations’ micronutrient needs, they should be created accounting for the country specific dietary patterns giving consideration to the socioeconomic context.

In deze publicatie wordt beschreven hoe de in CVB verband tot stand gekomen voedernormen voor deze voedingsstoffen tot stand zijn gekomen. De publicatie is het resultaat van een deskstudie waarbij allereerst de Duitse DLG normen en de Amerikaanse NRC normen zijn geëvalueerd. Daar waar nodig is gericht gekeken of er nieuwe studies beschikbaar zijn, of is teruggegrepen op de oorspronkelijke publicaties. Voor de macromineralen (calcium, fosfor, magnesium, natrium, kalium, chloor) zijn de voedernormen gebaseerd op de zgn. factoriële methode. Voor sporenelementen en de vitamines bleek deze benadering niet mogelijk. Het rapport bevat een groot aantal tabellen waarin de voedernormen voor de genoemde nutriënten voor alle relevante fysiologische stadia.

This report provides an overview of the available standardised analytical methods for the determination of nutrients in formula. This report focusses on the vitamins, inositol and choline compounds. In addition, several analytical method characteristics are provided i.e target compound(s) being actually measured, the matrixes wherein the methods have been validated and the method performance characteristics.

In deze publicatie wordt beschreven hoe de in CVB verband tot stand gekomen voedernormen voor deze voedingsstoffen tot stand zijn gekomen. De publicatie is het resultaat van een deskstudie waarbij allereerst de Duitse DLG normen en de Amerikaanse NRC normen zijn geëvalueerd. Daar waar nodig is gericht gekeken of er nieuwe studies beschikbaar zijn, of is teruggegrepen op de oorspronkelijke publicaties. Voor de macromineralen (calcium, fosfor, magnesium, natrium, kalium, chloor) zijn de voedernormen gebaseerd op de zgn. factoriële methode. Voor sporenelementen en de vitamines bleek deze benadering niet mogelijk. Het rapport bevat een groot aantal tabellen waarin de voedernormen voor de genoemde nutriënten voor alle relevante fysiologische stadia.

This report provides an overview of the available standardised analytical methods for the determination of nutrients in formula. This report focusses on the vitamins, inositol and choline compounds. In addition, several analytical method characteristics are provided i.e target compound(s) being actually measured, the matrixes wherein the methods have been validated and the method performance characteristics.

Tijdens de tweede ronde met leghennen zijn o.a. geëxpandeerd voer en fytase onderwerpen van onderzoek. Met geëxpandeerd voer kunnen gunstige technische resultaten behaald worden. Door de toepassing van fytase kan een lager fosfaatgehalte in de mest worden bereikt, waarschijnlijk zonder dat de technische resultaten veranderen.

De botsterkte van leghennen wordt door diverse factoren beonvloed. In dit artikel wordt ingegaan op de effecten van huisvesting, verlichting, diergewicht en voer met fytase op de botsterkte.

Door fytase toe te voegen aan het voer, komt meer fosfor beschikbaar voor het dier. Bij vleeskuikens wordt door Gist-brocades geadviseerd dat 500 FTU overeenkomt met 1 g Monocalciumfosfaat (MCP-P). Voor leghennen is het advies dat 300 FTU overeenkomt met 1 g MCP-P.

In april 1994 is in samenwerking met ID-DL0 een experiment uitgevoerd met vleeskalkoenen. Daarin is nagegaan hoeveel microbieel fytase nodig is om een hoeveelheid fosfor uit fytaat vrij te maken, die gelijkwaardig is aan 1 gram fosfor uit mononatriumfosfaat.

Dat vitaminen en mineralen een positieve invloed uit kunnen oefenen op specifieke lichaamsprocessen is bekend. Twee promovendi van Wageningen Universiteit richten zich op het mogelijke verband tussen vitamine B12, foliumzuur en vitamine D en verschillende leeftijdgerelateerde aandoeningen. De associatie tussen een verhoogd homocysteïnegehalte en een verhoogd risico op fracturen was aanleiding voor een groot trial onderzoek onder ouderen. Dit B-PROOF onderzoek loopt nog.

Dat vitaminen en mineralen een positieve invloed uit kunnen oefenen op specifieke lichaamsprocessen is bekend. Twee promovendi van Wageningen Universiteit richten zich op het mogelijke verband tussen vitamine B12, foliumzuur en vitamine D en verschillende leeftijdgerelateerde aandoeningen. De associatie tussen een verhoogd homocysteïnegehalte en een verhoogd risico op fracturen was aanleiding voor een groot trial onderzoek onder ouderen. Dit B-PROOF onderzoek loopt nog.

Introduction Adequate and safe micronutrient intake is important. Both insufficient and excessive intakes should be prevented as these can be associated with negative health effects. Therefore, the population intake distribution will ideally lay between insufficient and excessive intakes. For the development and evaluation of nutrition and food policy a good estimation of dietary micronutrient intake is of great importance. Aim Three challenges were addressed to improve the estimation of population micronutrient intake distributions: 1) how to estimate current habitual micronutrient intake when (detailed) data are lacking or data from different sources should be combined, 2) how to predict future intakes in order to support policy making, and 3) how to estimate a maximum safe fortification level per food item. The aim of this PhD-thesis is to further develop and apply statistical models which can cope with these challenges. Methods & Results Data from the Dutch National Food Consumption Surveys (DNFCSs) were used to develop and apply statistical models which can cope with the defined challenges. In addition, data from the Dutch food composition database (NEVO) and the Dutch dietary supplement database (NES) were used. Three main methodological improvements have been made. First, the combination of a deterministic approach with probabilistic approaches to be able to take into account uncertainty and variability were needed. This method was applied to estimate habitual iodine and salt intake distributions. From DNFCSs no detailed information was available on the discretionary use of (iodized) salt and no up to date information was available on the use of iodized salt in industrially processed foods. Estimates of the proportion of the population discretionarily using (iodized) salt and the proportion of industrially processed foods applying iodized salt were obtained from other data sources. The model accurately estimates habitual iodine and salt intake distributions when compared with studies measuring urinary iodine and sodium excretion. Additionally a framework was developed to simulate the habitual intake distribution for potential scenarios of future fortification strategies. Within this framework, deterministic and probabilistic approaches were combined when uncertainty or variability had to be taken into account. This framework was illustrated by the estimation of habitual folate-equivalent intake for different scenarios of mandatory or voluntary fortification with folic acid. Further this framework was applied to estimate the habitual iodine intake for several potential changes in the Dutch iodine policy and also for several scenarios of salt reduction strategies. A second methodological improvement was the development of a new statistical model to estimate habitual total micronutrient intake aggregated from food and dietary supplements. Within this 3-part model, habitual intake is estimated separately for a) intake from food for non-users of dietary supplements, b) intake from food for users of dietary supplements, and c) intake from dietary supplements for users only. Habitual total intake for the whole population was obtained by combination of the three separate habitual intake distributions (‘first shrink then add’). This 3-part model was illustrated by vitamin D intake for young children. With a more simple ‘first add then shrink’ approach the estimation of habitual total vitamin D intake distribution may give inconsistent results for the distribution of intake from foods and dietary supplements combined as compared to the intake from food only. In addition, this more simple approach may not be able to cope with multi modal distributions. With the newly developed model this inconsistency problem was solved and the multi-modal shape of the distribution as observed in the ‘raw’ data was preserved. Third, a model calculating the maximum safe fortification level per 100 kcal of a food was developed for the Dutch situation. By considering the tolerable upper intake level and reasonable high micronutrient intakes from food and dietary supplements, the ‘free space’ for voluntary fortification was calculated. This amount was divided over the amount of energy intake that can and may be fortified. The model was applied to derive safe maximum fortification levels for vitamin A, D, and folic acid. Based on these results the risk manager decided to legally allow voluntary fortification with vitamin D and folic acid up to a maximum level of 4.5 and 100 μg/100 kcal respectively. Conclusion The methodological improvements have resulted in higher accuracy for estimations of habitual intake distributions, which are essential for nutritional and food policy making. Furthermore, scenario analyses provide (under specific conditions) quantitative insight into proposed changes or areas such as maximum safe fortification levels. Several results and methods described are currently being used in research to assist Dutch and European food and nutrition policy making, which shows these methodologies are of immediate value to the practice of policy development and support.

Introduction Adequate and safe micronutrient intake is important. Both insufficient and excessive intakes should be prevented as these can be associated with negative health effects. Therefore, the population intake distribution will ideally lay between insufficient and excessive intakes. For the development and evaluation of nutrition and food policy a good estimation of dietary micronutrient intake is of great importance. Aim Three challenges were addressed to improve the estimation of population micronutrient intake distributions: 1) how to estimate current habitual micronutrient intake when (detailed) data are lacking or data from different sources should be combined, 2) how to predict future intakes in order to support policy making, and 3) how to estimate a maximum safe fortification level per food item. The aim of this PhD-thesis is to further develop and apply statistical models which can cope with these challenges. Methods & Results Data from the Dutch National Food Consumption Surveys (DNFCSs) were used to develop and apply statistical models which can cope with the defined challenges. In addition, data from the Dutch food composition database (NEVO) and the Dutch dietary supplement database (NES) were used. Three main methodological improvements have been made. First, the combination of a deterministic approach with probabilistic approaches to be able to take into account uncertainty and variability were needed. This method was applied to estimate habitual iodine and salt intake distributions. From DNFCSs no detailed information was available on the discretionary use of (iodized) salt and no up to date information was available on the use of iodized salt in industrially processed foods. Estimates of the proportion of the population discretionarily using (iodized) salt and the proportion of industrially processed foods applying iodized salt were obtained from other data sources. The model accurately estimates habitual iodine and salt intake distributions when compared with studies measuring urinary iodine and sodium excretion. Additionally a framework was developed to simulate the habitual intake distribution for potential scenarios of future fortification strategies. Within this framework, deterministic and probabilistic approaches were combined when uncertainty or variability had to be taken into account. This framework was illustrated by the estimation of habitual folate-equivalent intake for different scenarios of mandatory or voluntary fortification with folic acid. Further this framework was applied to estimate the habitual iodine intake for several potential changes in the Dutch iodine policy and also for several scenarios of salt reduction strategies. A second methodological improvement was the development of a new statistical model to estimate habitual total micronutrient intake aggregated from food and dietary supplements. Within this 3-part model, habitual intake is estimated separately for a) intake from food for non-users of dietary supplements, b) intake from food for users of dietary supplements, and c) intake from dietary supplements for users only. Habitual total intake for the whole population was obtained by combination of the three separate habitual intake distributions (‘first shrink then add’). This 3-part model was illustrated by vitamin D intake for young children. With a more simple ‘first add then shrink’ approach the estimation of habitual total vitamin D intake distribution may give inconsistent results for the distribution of intake from foods and dietary supplements combined as compared to the intake from food only. In addition, this more simple approach may not be able to cope with multi modal distributions. With the newly developed model this inconsistency problem was solved and the multi-modal shape of the distribution as observed in the ‘raw’ data was preserved. Third, a model calculating the maximum safe fortification level per 100 kcal of a food was developed for the Dutch situation. By considering the tolerable upper intake level and reasonable high micronutrient intakes from food and dietary supplements, the ‘free space’ for voluntary fortification was calculated. This amount was divided over the amount of energy intake that can and may be fortified. The model was applied to derive safe maximum fortification levels for vitamin A, D, and folic acid. Based on these results the risk manager decided to legally allow voluntary fortification with vitamin D and folic acid up to a maximum level of 4.5 and 100 μg/100 kcal respectively. Conclusion The methodological improvements have resulted in higher accuracy for estimations of habitual intake distributions, which are essential for nutritional and food policy making. Furthermore, scenario analyses provide (under specific conditions) quantitative insight into proposed changes or areas such as maximum safe fortification levels. Several results and methods described are currently being used in research to assist Dutch and European food and nutrition policy making, which shows these methodologies are of immediate value to the practice of policy development and support.

In dit artikel worden de resultaten weergegeven van de tweede ronde in de opfok stal voor leghennen. Bekeken zijn de effecten van fytase voeding en geëxpandeerd voer.

Biologische geitenhouders vragen zich af of een gezonde geitenhouderij mogelijk is zonder synthetische vitaminen. De afgelopen jaren zijn van verschillende groepen geiten bloedmonsters genomen voor bepaling van mineralen, spoorelementen en vitaminen. Ze zijn, waar mogelijk, vergeleken met bestaande referentiewaarden in Nederland en buitenlandse literatuur. Voor die bepalingen waarvoor referentiewaarde beschikbaar is, worden streefwaarden voorgesteld op basis van de bepalingen. Per element is gekeken of er tekorten (kunnen) ontstaan.

Biologische geitenhouders vragen zich af of een gezonde geitenhouderij mogelijk is zonder synthetische vitaminen. De afgelopen jaren zijn van verschillende groepen geiten bloedmonsters genomen voor bepaling van mineralen, spoorelementen en vitaminen. Ze zijn, waar mogelijk, vergeleken met bestaande referentiewaarden in Nederland en buitenlandse literatuur. Voor die bepalingen waarvoor referentiewaarde beschikbaar is, worden streefwaarden voorgesteld op basis van de bepalingen. Per element is gekeken of er tekorten (kunnen) ontstaan.

Tijdens de eerste ronde opfok van leghennen in de nieuwe proefaccommodatie is gekeken naar de droging van de mest op de mestbanden met mestbandbeluchting. Ook is een relatie gelegd met de drie voeders en de twee merken waarvan in het artikel 'geëxpandeerd voer geeft goede resultaten' uit dit periodiek, de technische resultaten zijn besproken.

De eerste ronde opfok van leghennen in de nieuwe proefaccommodatie is onlangs afgesloten. De proef met geëxpandeerd voer met fytase liet positieve technische resultaten zien. Toevoeging van fytase aan een meelvoer gaf wisselende resultaten.

In de biologische geitenhouderij is weidegang verplicht en bevat het rantsoen ook in de stalperiode meer ruwvoer dan in de gangbare geitenhouderij. Ook wordt soms eigen graan gevoerd ter vervanging van commercieel krachtvoer. De voorziening met mineralen, spoorelementen en vitaminen moet daarbij bewuster gestuurd worden. Binnen het project Biogeit is op veertien biologische geitenbedrijven bloed onderzocht op gehalten aan mineralen en vitaminen. Ook is gekeken naar de gehalten in het rantsoen. In dit artikel staat zink centraal

The evaluation of specific demands for organic feed focussed on feed demands for four fish species which can be cultured in Recirculation Aquaculture Systems (RAS), tilapia, African Catfish, shrimp and turbot. The evaluation of the various feed formulations indicates that there are several ingredients, which are common for the four species, and will therefore be used for further elaboration on the organic availability. These feed ingredients, are: fishmeal and oil, corn meal, wheat meal, blood meal, vitamin mix, mineral mix, and antioxidants. Besides the evaluation of the feed ingredients an inventory was made on the demands set by three key organic standards and legislation documents; European legislation (in prep), IFOAM and Naturland. A draft consensus standard containing a synthesis of all demands has been described. The implication of the demands, and the possibilities and bottlenecks for organic feed production were evaluated for the selected feed ingredients. It was concluded that organic feed production for RAS can meet the general criteria set for feed, on GMO material and organic composition. However, for the production of organic feed, a bottleneck will be the necessary requirement of synthetic amino acids for health improvement. The lack of these amino acids in organic feed can result in potential disadvantage for animal needs. This raw material restrictions will most likely also result in the lack of possibilities for fine tuning the feed for animal needs

The evaluation of specific demands for organic feed focussed on feed demands for four fish species which can be cultured in Recirculation Aquaculture Systems (RAS), tilapia, African Catfish, shrimp and turbot. The evaluation of the various feed formulations indicates that there are several ingredients, which are common for the four species, and will therefore be used for further elaboration on the organic availability. These feed ingredients, are: fishmeal and oil, corn meal, wheat meal, blood meal, vitamin mix, mineral mix, and antioxidants. Besides the evaluation of the feed ingredients an inventory was made on the demands set by three key organic standards and legislation documents; European legislation (in prep), IFOAM and Naturland. A draft consensus standard containing a synthesis of all demands has been described. The implication of the demands, and the possibilities and bottlenecks for organic feed production were evaluated for the selected feed ingredients. It was concluded that organic feed production for RAS can meet the general criteria set for feed, on GMO material and organic composition. However, for the production of organic feed, a bottleneck will be the necessary requirement of synthetic amino acids for health improvement. The lack of these amino acids in organic feed can result in potential disadvantage for animal needs. This raw material restrictions will most likely also result in the lack of possibilities for fine tuning the feed for animal needs

Algemeen wordt aangenomen dat groente en fruit gezond zijn voor de mens. Maar hoe onderbouwd is de gedachte eigenlijk dat appels en peren gezond zijn

In de biologische geitenhouderij is weidegang verplicht en bevat het rantsoen ook in de stalperiode meer ruwvoer dan in de gangbare geitenhouderij. Ook wordt soms eigen graan gevoerd ter vervanging van commercieel krachtvoer. De voorziening met mineralen, spoorelementen en vitaminen moet daarbij bewuster gestuurd worden. Binnen het project Biogeit is op veertien biologische geitenbedrijven bloed onderzocht op gehalten aan mineralen en vitaminen. Ook is gekeken naar de gehalten in het rantsoen. In dit artikel staat zink centraal

Algemeen wordt aangenomen dat groente en fruit gezond zijn voor de mens. Maar hoe onderbouwd is de gedachte eigenlijk dat appels en peren gezond zijn

Flavoprotein oxidases represent an interesting class of enzymes because of their increasing interest to the fine-chemical and pharmaceutical industries. Owing to their high regio- and enantioselectivity and low costs, the use of oxidases is preferred over classical organic chemistry. A specific class of oxidases is formed by carbohydrate oxidases. Many flavin-harboring carbohydrate oxidases contain a vocalently linked FAD corfactor. Therefore, the approach used in this thesis to find carbohydrate oxidases was based on searching the genome databases for putative covalent FAD-containing proteins, thereby increasing the chance of finding an oxidase. We focused the search for novel carbohydrate oxidases on the vanillyl-alcohol oxidase family of flavoproteins. This family harbors a large number of putative covalent flavoproteins, and most known carbohydrate oxidases belong to this family.

Flavoprotein oxidases represent an interesting class of enzymes because of their increasing interest to the fine-chemical and pharmaceutical industries. Owing to their high regio- and enantioselectivity and low costs, the use of oxidases is preferred over classical organic chemistry. A specific class of oxidases is formed by carbohydrate oxidases. Many flavin-harboring carbohydrate oxidases contain a vocalently linked FAD corfactor. Therefore, the approach used in this thesis to find carbohydrate oxidases was based on searching the genome databases for putative covalent FAD-containing proteins, thereby increasing the chance of finding an oxidase. We focused the search for novel carbohydrate oxidases on the vanillyl-alcohol oxidase family of flavoproteins. This family harbors a large number of putative covalent flavoproteins, and most known carbohydrate oxidases belong to this family.

Tijdens dit onderzoek zijn een aantal nieuwe methoden ontwikkeld voor het maken van enantiomeerzuivere haloalcoholen, epoxiden en andere verbindingen. Deze stoffen vinden onder andere toepassing in het onderzoek naar en de productie van nieuwe medicijnen, kunststoffen, harsen e.d. Een van de belangrijkste speerpunten van de methoden ontwikkeld tijdens dit promotieonderzoek was het gebruik van enzymen om reacties te versnellen, eventueel in combinatie met katalysatoren op basis van metalen.

Uit de analyse van de voedingswaarden van paddenstoelen en verschillenden onderzoeken blijkt dat een advies om de paddenstoelenconsumptie bij de bevolking te verhogen op zijn plaats is. Er zijn volop mogelijkheden om de ontwikkeling van functioneel foods op basis van paddenstoelen te stimuleren maar dan moeten de gezondheids-effecten voor claims wel nog verder worden onderbouwd.

Melk van biologische en gangbare oorsprong laat verschillen in vetzuursamenstelling zien. Uit onderzoek in het buitenland zijn ook verschillen gevonden in vitaminehoeveelheden tussen melk van biologische of gangbare herkomst. Dit was aanleiding om ook in Nederlandse winkelmelk na te gaan of de vitamines een onderscheidend kenmerk vormen. Daarnaast is onderzocht of biologische en gangbare melk onderscheidend is ten aanzien van smaak.

Tijdens dit onderzoek zijn een aantal nieuwe methoden ontwikkeld voor het maken van enantiomeerzuivere haloalcoholen, epoxiden en andere verbindingen. Deze stoffen vinden onder andere toepassing in het onderzoek naar en de productie van nieuwe medicijnen, kunststoffen, harsen e.d. Een van de belangrijkste speerpunten van de methoden ontwikkeld tijdens dit promotieonderzoek was het gebruik van enzymen om reacties te versnellen, eventueel in combinatie met katalysatoren op basis van metalen.

Melk van biologische en gangbare oorsprong laat verschillen in vetzuursamenstelling zien. Uit onderzoek in het buitenland zijn ook verschillen gevonden in vitaminehoeveelheden tussen melk van biologische of gangbare herkomst. Dit was aanleiding om ook in Nederlandse winkelmelk na te gaan of de vitamines een onderscheidend kenmerk vormen. Daarnaast is onderzocht of biologische en gangbare melk onderscheidend is ten aanzien van smaak.

Uit de analyse van de voedingswaarden van paddenstoelen en verschillenden onderzoeken blijkt dat een advies om de paddenstoelenconsumptie bij de bevolking te verhogen op zijn plaats is. Er zijn volop mogelijkheden om de ontwikkeling van functioneel foods op basis van paddenstoelen te stimuleren maar dan moeten de gezondheids-effecten voor claims wel nog verder worden onderbouwd.

In de EU is de discussie over het wel of niet toestaan van synthetische vitamines in veevoer weer opgelaaid. Met name de noordelijke EU-landen willen af van het verbod op deze stoffen omdat zij vrezen voor diergezondheidsklachten. Op vijf melkveebedrijven waar al jaren geen vitamines worden bijgevoerd, zijn de gevolgen onderzocht. Onderzoek is gedaan naar de vitaminegehalten in het voer, de bloedwaarden van de koeien, de diergezondheid en de vruchtbaarheid

De auteur gaat uitvoerig in op de risico's van zowel te veel als te weinig mineralen en vitaminen. Beide uitersten kunnen schadelijk zijn.

Op Europees niveau is de discussie over het definitief opheffen van het verbod op synthetische vitaminen in de biologische rundveehouderij weer geopend. Nederlands onderzoek geeft aan dat er nauwelijks tekorten aan vitaminen optreden, met uitzondering gedurende de droogstand.

In een onderzoek binnen het project biogeit zijn 3 bedrijven, die geen synthetische vitaminen voeren, in maart 2005 doorgelicht op vitminegehalten in zowel het rantsoen als het bloed van de dieren. Bij het niet toevoegen van extra vitaminen lijken problemen zich te concentreren in de stalperiode rond vitamine E en in mindere mate vitamine A.

De auteur gaat uitvoerig in op de risico's van zowel te veel als te weinig mineralen en vitaminen. Beide uitersten kunnen schadelijk zijn.