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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    The tree under which you sit : district-level management and leadership in maternal and newborn health policy implementation in the Greater Accra Region, Ghana
    Kwamie, A. - \ 2016
    Wageningen University. Promotor(en): Han van Dijk; I.A. Agyepong. - Wageningen : Wageningen University - ISBN 9789462576742 - 158
    health policy - birth - pregnancy - policy - management - administration - ghana - west africa - gezondheidsbeleid - geboorte - zwangerschap - beleid - bedrijfsvoering - bestuur - ghana - west-afrika

    Health system governance has to do with decision-making – who makes decisions, when, where, how and why. At the district level – the level of care which operationalises health policies – governance is critical, yet remains little understood. Governance has the ability to influence health system performance, and this is essential in maternal and newborn health, where timely decisions are required to support policy implementation. In this regard, district managers are particularly important. They are the link in the middle of the health system, connecting top-end policy formulation to bottom-end implementation. Their abilities to interpret, translate, support and challenge policy will have an effect on what gets operationalised. However, capacity weaknesses in district management and leadership are often cited as a factor in poor health system performance.

    This thesis seeks to deepen understandings of district-level management, leadership and decision-making for policy and programme management and implementation for maternal and newborn health. Within this, the thesis also seeks to understand the scope for change that an intervention to strengthen management and leadership capacities can bring.

    This thesis contributes to the applied field of health policy and systems research by drawing on policy implementation theory, organisational management theory and complexity theory as its theoretical basis. A realist approach methodology was undertaken to understand the contexts in which district managers are embedded, how this influences their decision-making, and what the effects of a managerial intervention are, given these contexts. The thesis followed an embedded case study flexible design. The first case study was an exploratory qualitative case study to understand how and why district managers make decisions in maternal and newborn health policy implementation. The second case study was an historical case study of district manager decision-space over time. The third case study was an explanatory qualitative case study of the management and leadership intervention. The final validation of our theorising throughout the cases was achieved through the administration of a questionnaire across all district health management teams of the Great Accra Region.

    This thesis demonstrates that district managers find themselves in contexts of strong hierarchical authority and resource uncertainty – in particular, lacking financial transparency. This promotes a management and leadership typology which attunes managers towards serving the health system bureaucracy, resulting in reduced district-level responsiveness to maternal and newborn health challenges. The outcome is that district manager decision-space is narrow surrounding resource allocation decisions, and this in turn affects local planning programming and management.

    The thesis further demonstrates that broader patterns of centralised governmental decision-making have affected the development of the district health system over time. Particularly, the sequencing of decentralisation processes has ensured that national-level decision-making has remained empowered in contrast to district-level decision-making. System fragmentation – through reduced Government of Ghana funds and increasingly verticalised donor funds – has also been a contributor. This accounts for the observed hierarchical authority and resource uncertainty which affects district managers. As a result of these contexts, this thesis also showed that an intervention to strengthen management and leadership capacities was limited in its sustainability.

    This thesis raises the issues of health system organisation as critical to the potential of district management and leadership effectiveness. It provides evidence that weaknesses in district management and leadership arise out of the organisational governance mismatches in autonomy and responsibility. It suggests that in strengthening management and leadership, approaches which seek to address organisational capacities, not only individual capacities, are needed to convey sustainable change. Advancements in this regard have the scope to improve district manager decision-making for maternal and newborn health policy and programme implementation in the future.

    Pupping habitat ofd grey seals in the Dutch Wadden Sea
    Brasseur, S.M.J.M. ; Groot, A.V. de; Aarts, G.M. ; Dijkman, E.M. ; Kirkwood, R.J. - \ 2015
    Den Burg : IMARES (Report / IMARES C009/15) - 104
    halichoerus grypus - habitats - whelping - birth - vegetation - geomorphology - wadden sea - halichoerus grypus - habitats - jongen werpen - geboorte - vegetatie - geomorfologie - waddenzee
    Atlantic grey seals (Halichoerus grypus grypus) started recolonising Dutch coastal haul-outs in the 1950s, after practically 500 years of rarity in the Dutch coastal zone which was caused mainly by human hunting. The first pup-birth was recorded in 1985 at the Wadden Sea sandbank of Engelschhoek. Sandbanks in the Wadden Sea may form and recede in periods of decades, but may change abruptly as a result of a single storm. These rapidly evolving places are not the perfect breeding habitat for grey seals, which exhibit long-term fidelity to breeding sites and only reluctantly shift. Little is known of the geomorphology of the currently utilised pupping sites, nor the implications of change in structure on future occupation and selection of new sites.
    Regio heeft grote invloed op levensvatbaarheid
    Pellikaan, F. ; Ouweltjes, W. ; Windig, J.J. ; Muskens, J. ; Linden, R. van der; Pelt, M.L. van; Calus, M.P.L. - \ 2014
    Veeteelt 31 (2014)14. - ISSN 0168-7565 - p. 10 - 13.
    melkveehouderij - kalveren - levensvatbaarheid - geboorte - vaarzen - grote landbouwbedrijven - bedrijfsgrootte in de landbouw - landbouwstatistieken - bedrijfsvergelijking in de landbouw - invloeden - dairy farming - calves - viability - birth - heifers - large farms - farm size - agricultural statistics - farm comparisons - influences
    Een afname van zes procent levend geboren kalveren van vaarzen tussen 1995 en 2010 was aanleiding voor nieuw sectoronderzoek. Uit de inventarisatie blijkt dat naast bekende factoren als draagtijd en geboorteverloop de regio waar het bedrijf is gehuisvest en het seizoen van afkalven zorgen voor opmerkelijke verschillen in levensvatbaarheid van kalveren.
    Naar een probleemloos afkalvende dikbilkoe = Towards an easy-calving double-muscled cow
    Napel, J. ten; Hoving, A.H. ; Bohte-Wilhelmus, D.I. ; Hannewijk, P. - \ 2012
    Lelystad : Wageningen UR Livestock Research (Rapport / Wageningen UR Livestock Research 648) - 40
    rundveehouderij - vleesvee - dierenwelzijn - keizersnede - dierveredeling - selectief fokken - geboorte - dierlijke productie - diergezondheid - vleesveerassen - cattle husbandry - beef cattle - animal welfare - caesarean section - animal breeding - selective breeding - birth - animal production - animal health - beef breeds
    A measuring and breeding programme has been developed for easy calving doublemuscled beef cattle.
    Vijftig procent natuurlijk kalven is economisch te verantwoorden. Een kwestie van durf?
    Eilers, C.H.A.M. - \ 2012
    Veeteeltvlees (2012). - ISSN 1570-3312 - p. 10 - 13.
    rundveehouderij - vleesproductie - geboorte - dierenwelzijn - kosten-batenanalyse - agrarische bedrijfsvoering - cattle husbandry - meat production - birth - animal welfare - cost benefit analysis - farm management
    Meer natuurlijk afkalven vergt een gericht fokkerijbeleid en een andere houding van vleesveehouders ten opzichte van natuurlijk afkalven. In onderzoek is nagegaan of een gedeeltelijke omschakeling de economische resultaten in de praktijk onder druk zet.
    Natuurlijke geboorte extreme vleesrassen
    Napel, J. ten - \ 2012
    V-focus 9 (2012)5a. - ISSN 1574-1575 - p. 15 - 17.
    rundveehouderij - vleesvee - verbeterd roodbont - belgisch witblauw - dierveredeling - fokwaarde - geboorte - dierenwelzijn - dierlijke productie - cattle husbandry - beef cattle - improved red pied - belgian blue - animal breeding - breeding value - birth - animal welfare - animal production
    Dikbilkoeien die probleemloos natuurlijk afkalven is geen utopie. Na drie jaar voorbereidend onderzoek en vier jaar onderzoek in de praktijk binnen het project Natuurlijke Luxe is duidelijk hoe dat moet. Het belangrijkste is om met fokkerij de ruimte in het geboortekanaal te vergroten. Of dat ook gebeurt, is nu een kwestie van willen en doen.
    Lammerensterfte, leverbot en ureum bij melkschapen
    Verkaik, J.C. ; Smolders, G. - \ 2010
    Lelystad : Wageningen UR Livestock Research (Rapport / Wageningen UR Livestock Research 417) - 27
    biologische landbouw - schapenhouderij - mortaliteit - lammeren - schapen - leverbot - ureum - geboorte - agrarische bedrijfsvoering - quarantaine - eiwitopname - zware metalen - organic farming - sheep farming - mortality - lambs - sheep - liver flukes - urea - birth - farm management - quarantine - protein uptake - heavy metals
    The monitored lamb mortality at organic dairy sheep farms is relativly high with big differences. Mortality over 10% is caused by poor management and infectious abortions. Short term improvements needs a structured approach. Treatment of the dairy sheep is limited to the dry period. Avoiding infection by housing ewes in early lactation appears effective. Liver fluke is well predictable on the prognosis and the fluke and grazing history. The time between infection intake and appearance in blood or dung makes these researches risky. Urea appears dependable upon the amount of protein fed. Protein wastage reduces when more energy is fed.
    Minder keizersneden bij dikbillen
    Napel, J. ten - \ 2010
    Kennis Online 7 (2010)nov. - p. 8 - 8.
    rundveehouderij - vleesvee - keizersnede - geboorte - dierveredeling - cattle husbandry - beef cattle - caesarean section - birth - animal breeding
    Vrijwel alle dikbilkoeien komen met een keizersnee ter wereld. Wageningen UR Livestock Research werkt in het project ‘Natuurlijke luxe’ met de Federatie van Vleesveestamboeken Nederland aan meer natuurlijke geboorten.
    Cultuuromslag nodig : natuurlijke Luxe bij Verbeterd Roodbont : dier & welzijn
    Napel, J. ten - \ 2010
    V-focus 7 (2010)5A. - ISSN 1574-1575 - p. 24 - 25.
    dierenwelzijn - geboorte - rundveerassen - rundveehouderij - rassen (dieren) - verbeterd roodbont - animal welfare - birth - cattle breeds - cattle husbandry - breeds - improved red pied
    Het streven naar meer natuurlijke geboorten bij Verbeterd Roodbont is in een nieuwe fase gekomen. Het stamboek heeft de trekkende rol overgenomen van Wageningen UR Livestock Research en stimuleert en ondersteunt zijn leden met concreet advies. Het doel wat het stamboek voor ogen heeft is 50 procent natuurlijke geboorten in 2020. Een portret van een cultuuromslag.
    Meetprogramma dikbilrassen biedt veel perspectief
    Napel, J. ten - \ 2010
    V-focus 7 (2010)5. - ISSN 1574-1575 - p. 42 - 43.
    rundveehouderij - vleesvee - vleesveerassen - belgisch witblauw - geboorte - dierveredeling - selectief fokken - bekken - verbeterd roodbont - cattle husbandry - beef cattle - beef breeds - belgian blue - birth - animal breeding - selective breeding - pelvis - improved red pied
    De inwendige bekkenhoogte van een koe vertoont veel variatie, is sterk erfelijk en hangt nauw samen met de kans op een natuurlijke geboorte van het kalf. Dit maakt selectie voor een grotere inwendige bekkenhoogte een geschikt instrument om bij Verbeterd Roodbont en Belgisch Witblauw vleesvee te selecteren voor natuurlijke geboorten.
    Sensor signaleert naderende geboorte
    Ipema, A.H. ; Hogewerf, P.H. ; Bleumer, E.J.B. - \ 2009
    V-focus 2009 (2009)12. - ISSN 1574-1575 - p. 24 - 25.
    melkveehouderij - melkkoeien - sensors - geboorte - kalven - dairy farming - dairy cows - sensors - birth - calving
    Met de nieuwe generatie draadloze sensoren, die momenteel in ontwikkeling is en langzaam voor de praktijk beschikbaar komt, kunnen steeds meer signalen van het individuele dier automatisch worden vastgelegd, zoals een naderende geboorte
    Ruimere koe... lichter kalf
    Napel, J. ten - \ 2008
    V-focus 5 (2008)2. - ISSN 1574-1575 - p. 36 - 37.
    rundveehouderij - vleesvee - geboorte - keizersnede - bevallingscomplicaties - dierenwelzijn - probleemoplossing - werkgroepen - cattle husbandry - beef cattle - birth - caesarean section - parturition complications - animal welfare - problem solving - working groups
    Hoe buig je de cultuur van systematisch toepassen van een keizersnede om naar meer natuurlijke geboorten? Wageningen UR begeleidt dit proces door vleesveehouders in werkgroepen zelf te laten zoeken naar oplossingen
    Baren op Beveland : vruchtbaarheid en zuigelingensterfte in Goes en omliggende dorpen gedurende de 19e eeuw
    Hoogerhuis, O.W. - \ 2003
    Wageningen University. Promotor(en): A.M. van der Woude. - Wageningen : S.n. - ISBN 9789058088581 - 333
    demografie - geschiedenis - geboorte - zuigelingensterfte - bevolkingsstatistieken - borstvoeding - zuigelingenvoedsel - nederland - menselijke vruchtbaarheid - zeeland - demography - history - birth - infant mortality - vital statistics - breast feeding - human fertility - infant foods - netherlands - zeeland
    This study deals with the high infant mortality on Zuid-Beveland, a region which is situated in the middle of the province of Zeeland in the south western part of the Netherlands. The study describes on a micro-level the development of infant mortality during the period 1811-1900 in Goes, a small market town, and four neighbouring villages. This research is based on family reconstitution data. The analyses show that infant-feeding practices were the most important determinants of fertility and mortality levels, followed by the season in which children were born. This study shows that women were likely to cease breastfeeding during the months betweenJulyto October. The increasing demand for women's time by agricultural activities, especially during the harvest season and in the summer-months, caused the absence of the mother in the family.Which led to inferior food for the infants and to an increase of infant mortality rate.High temperatures in hot summers also raised the mortality rate. Exploration of the relationship between fertility and mortality at the micro-level further showed that the probability of conception during the first year following giving birth was greater when the infant died than when the infant survived. The evidence of 'replacing' children who had died, casts new light on this apparent change in the balance between fertility and infant mortality in the middle of the nineteenth century.
    Extra dietary starch in late-pregnant sows fed a high fibre diet: effect on litter weight at birth
    Peet-Schwering, C.M.C. van der; Binnendijk, G.P. ; Verstegen, M.W.A. - \ 2002
    Lelystad : Praktijkonderzoek Veehouderij (Praktijkboek / Praktijkonderzoek Veehouderij 19) - 13
    zeugenvoeding - samenstelling - zetmeel - vet - voeropname - worpgewicht - geboorte - zeugen - zwangerschap - sow feeding - composition - starch - fat - feed intake - litter weight - birth - sows - pregnancy
    An experiment with 141 multiparous pregnant sows was conducted to investigate whether the supply of glucogenic energy at the end of pregnancy may be insufficient for an optimal growth of the foetuses in sows that are fed a diet with a high level of non-starch polysaccharides (NSP) and low level of starch. Sows were fed one of three diets from day 85 of pregnancy until parturition: : :Sows were fed a high NSP low starch diet. The daily intake of starch and sugar was 500 g. : :Sows were fed the same diet in the same amount as the sows in treatment 1 plus an extra daily amount of 500 g starch from wheat starch (is glucogenic energy). This means that the sows were fed 0.58 kg/d extra wheat starch (is 6.73 MJ glucogenic NE) during the last month of pregnancy. : :Sows were fed the same diet in the same amount as the sows in treatment 1 plus an extra daily amount of 200 g soya oil (is 6.73 MJ lipogenic NE). This treatment was added because otherwise it will not be clear whether energy or glucogenic energy is thelimiting factor. : :From day 1 of day 85 of pregnancy all sows were fed the high NSP low starch diet. During lactation all sows were fed the same lactation diet. Effects on litter performance, on changes in body weight and backfat thickness of the sows, and on feed intakeduring lactation were studied. The supply of extra dietary starch or extra dietary fat in late-pregnant sows that were fed a high NSP low starch diet did not increase litter weight at birth. This suggests that sows that were fed the high NSP low starch diet received sufficient glucogenic energy for foetal development. : :The number of stillborn piglets was numerically higher in sows that received extra dietary fat at the end of pregnancy. Sows that were fed extra dietary starch or extra dietary fat increased more in weight and backfat thickness during late pregnancy than sows that were fed the high NSP low starch diet. Decreases in weight and backfat thickness during lactation were similar for the three experimental treatments. Voluntary feed intake during lactation was slightly decreased in sows that were fed extra starch or extra fat in late pregnancy. :The present study shows that late-pregnant sows can be fed a high NSP low starch diet without adverse effects on litter weight at birth. A daily intake of 500 to 600 g starch and sugar in latepregnant sows seems sufficient for optimal growth of the foetuses.
    De invloed van geboorte-inductie en het tijdstip van vlekziekte-parvo-vaccinatie tijdens de zoogperiode op het interval spenen-bronst van zeugen
    Binnendijk, G. ; Vesseur, P. ; Vonk, M. - \ 1999
    Praktijkonderzoek varkenshouderij 13 (1999)1. - ISSN 1382-0346 - p. 22 - 24.
    zeugen - geboorte - zogen - oestrus - lactatieduur - drachtigheidsperiode - vaccinatie - parvoviridae - erysipelothrix - infectieziekten - sows - birth - suckling - oestrus - lactation duration - gestation period - vaccination - parvoviridae - erysipelothrix - infectious diseases
    Het effect van het al dan niet toepassen van geboorte-inductie in combinatie met het tijdstip van het toedienen van een vlekziekte-parvo-vaccinatie is onderzocht. Geboorte-inductie heeft effect op de drachtduur, het geboortegewicht van de biggen en het percentage biggen met spreidzit.
    Wederom goede aflamresultaten in het Low-inputsysteem!
    Verkaik, J. - \ 1998
    Praktijkonderzoek Rundvee, Schapen en Paarden. Praktijkonderzoek 11 (1998)6. - ISSN 1386-8470 - p. 4 - 5.
    schapen - low input landbouw - scharrelhouderij - milieueffect - geboorte - ontwikkeling - productiviteit - sheep - low input agriculture - free range husbandry - environmental impact - birth - development - productivity
    Het Low-input systeem, gekenmerkt door het ontbreken van huisvesting en het niet verstrekken van krachtvoer, heeft wederom goede aflamresultaten behaald.
    Thyroid hormones and iodide in the near-term pregnant rat
    Versloot, P. - \ 1998
    Agricultural University. Promotor(en): D. van der Heide. - S.l. : Versloot - ISBN 9789054858065 - 133
    metabolisme - schildklierhormonen - jodide - hormonale controle - voortplanting - ontwikkeling - schildklier - bevruchting - zwangerschap - geboorte - ratten - metabolism - thyroid hormones - iodide - hormonal control - reproduction - development - thyroid gland - fertilization - pregnancy - birth - rats

    Thyroid hormones, thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are produced by the thyroid gland. To synthesize thyroid hormones the thyroid needs iodide. The uptake of iodide as well as the production and secretion of T4 and T3 by the thyroid gland is regulated by thyrotropin (TSH), which is produced by the pituitary. However, most of the biologically active form, T3, is produced from T4 via monodeiodination in peripheral tissues.

    This reaction is catalyzed by the deiodinases, type I (ID-I) in liver and kidney, and type II (ID-II) in the central nervous system and brown adipose tissue (BAT). T4 and T3 concentrations differ in the various tissues, like the contribution of T3 produced locally from T4. A large portion of the T3 produced in the liver enters the circulation, whereas T3 produced in the brain and cerebellum is mainly used locally.

    The production, distribution and transport of thyroid hormones are influenced by several (patho)physiological conditions. In this study we concentrated on the effects of pregnancy on maternal thyroid hormone metabolism. It is well known that thyroid hormones are very important for normal fetal development, especially of the central nervous system. During development thyroid hormones produced by the mother, mainly T4, contribute to the fetal thyroid hormone pools before and also after onset of fetal thyroid function. Insufficient production of maternal thyroid hormones during pregnancy can result in permanent brain damage in the offspring.

    At the end of gestation the concentrations of T4 and T3 in maternal plasma and tissues have decreased. In order to gain more insight into the effects of pregnancy on the production, distribution, and transport of thyroid hormones in the mother we performed kinetic experiments with T4 and T3 using nonpregnant and near-term pregnant rats (chapter 2). A bolus injection of [125I]T4 and [131I]T3 was given, and blood samples were taken at regular times during the next twenty-four hours.

    Physiological para-meters of the production, interpool transport, distribution and metabolism of T4 and T3 were estimated by means of a three-compartment model. According to this model three compartments can be distinguished: 1. the plasma; 2. the fast pool; and 3. the slow pool. Liver and kidney are considered to be the main components of the fast pool, whereas skin, muscles and brain belong to the slow pool.

    In the near-term pregnant rat the production and distribution of T4 remained unchanged. The transport of T4 from plasma to the fast pool was more than tripled, whereas transport to the slow pool remained constant. We suggest that in the near-term pregnant rat available T4 was distributed between the maternal and fetal compartments by means of very fast transport. This hypothesis is based on the fact that it seems unlikely that the transport of T4 to maternal liver and kidney, which are considered to be the main components of the fast pool, will have increased that much in the near-term pregnant rat. This was confirmed by the results of steady-state, double isotopic experiments using nonpregnant and near-term pregnant rats (chapter 3).

    In this study, the rats received a continuous simultaneous infusion of [125I]T4 and [131I]T3 in order to achieve equilibrium in all tissues. With this method it was possible to calculate the T4 and T3 concentrations, the relative contributions of plasma-derived vs. locally produced T3, the thyroidal T4 and T3 secretion rates, and the plasma-to-tissue ratios for T4 and T3. Indeed, the transport of T4 to liver and kidney, as well as almost all other maternal organs, was diminished. Since the production of T4 remained unchanged this implies that T4 is transported to another compartment, i.e. the feto-placental compartment. This compartment was not measured in these studies.

    The plasma appearance rate for T3 remained constant in the near-term pregnant rat. This was accomplished by an increase in the secretion of T3 by the thyroid and a decrease in locally produced T3. Less T3 was transported from plasma to liver, kidney, BAT and pituitary. ID-I activity in liver, and ID-II activity in the brain both increased during pregnancy. However, this did not result in an increase in the local conversion of T4 to T3 in these tissues. In the liver the contribution of T3 produced locally remained constant, while in the brain even a decrease was found.

    The insufficient availability of T4 in maternal tissues, as demonstrated by the lower T4 concentrations, might explain the discrepancy between deiodinase activities and the local production of T3. The transport of T4 to the feto-placental compartment resulted indirectly in a deficiency of T3 in the maternal organs. We can conclude that pregnancy affects maternal thyroid hormone metabolism. The mother has to share the available thyroid hormones, especially T4, with the fetuses.

    Iodide is an essential element for the synthesis of thyroid hormones. In rats the fetal thyroid is capable of producing thyroid hormones on day 18 of gestation. Iodide is transported across the placenta from the maternal to the fetal circulation. In chapter 4 we assessed iodide uptake by the maternal thyroid, while the iodide uptake by the fetal thyroid was estimated. We measured the in vivo uptake of 125I by the thyroid continuously. By using the specific activity of iodide in the urine we were able to calculate the absolute iodide uptake in the thyroid.

    Pregnancy resulted in a decrease in the absolute thyroidal iodide uptake. On day 20 of pregnancy the fetal thyroid is already capable of concentrating iodide. However, the difference in absolute iodide uptake by the maternal thyroid, compared to nonpregnant controls, cannot fully be explained by the transport of iodide to the fetal compartment and/or the mammary glands. The decrease in iodide uptake by the maternal thyroid has no impact on the thyroidal production of thyroid hormones.

    Iodine deficiency can lead to disturbed physical and mental development. In large populations in the world iodine intake is marginally deficient. For this reason a marginal iodine deficiency, instead of the more common severe iodine deficiency, was induced in our rats. We used this model to study the effects of marginal iodine deficiency on iodide metabolism (thyroidal iodide uptake; chapter 4) and thyroid hormone metabolism (kinetic experiments; chapter 5) in near-term pregnant rats.

    The absolute iodide uptake by the maternal thyroid was not affected by marginal iodine deficiency. The decreased plasma inorganic iodide was compensated by an increase in thyroidal clearance. A similar compensation was not found for the fetus; the uptake of iodide by the fetal thyroid decreased by 50 % during marginal iodine deficiency. During this marginal iodine deficiency plasma T4 and T3 remained constant in nonpregnant as well as near-term pregnant rats. The production rate and the plasma clearance rate for T4 were both decreased.

    No effects of marginal iodine deficiency on pool sizes and transport rates were found for nonpregnant rats. In the near-term pregnant rat marginal iodine deficiency resulted in a marked decrease in the transport of T4 from plasma to the fast pool. For T3 an increase in the production rate and plasma clearance rate was found for nonpregnant, marginally iodine- deficient rats, while these parameters were slightly decreased in near-term pregnant rats. Marginal iodine deficiency induced a 50 % decrease in the interpool transport rates of T3 between plasma and the fast pool in near-term pregnant rats. The hepatic activity of ID-I was increased as a result of marginal iodine deficiency in nonpregnant as well as near-term pregnant rats.

    On the basis of the results of thyroid hormone studies in normal pregnant rats (chapter 2 and 3) we suggest that during marginal iodine deficiency less maternal T4 is available for the fetal compartment. Together with the lower uptake of iodide by the fetal thyroid this can lead to diminished levels of thyroid hormone of maternal and fetal origin in the fetal organs. In this case, marginal iodine deficiency will have a negative effect on fetal development, especially of the brain.

    Another situation which irreversibly affects fetal brain development is maternal hypothyroidism. Two different levels of hypothyroidism were induced in female rats, by giving thyroidectomized rats two different doses of T4 and T3. The effects of hypothyroidism on maternal thyroid hormone metabolism in near-term pregnant rats (kinetic experiment, chapter 6) were studied. Plasma T4 and T3 levels were very low severely hypothyroid animals, whereas only plasma T3 was decreased in the mildly hypothyroid group. Even during this mild hypothyroidism profound alterations in the transport rates of T4 were found compared to intact, pregnant rats. The transport of T4 from plasma to the fast pool was decreased. Therefore, it appears that even during mild hypothyroidism the transport of T4 to the feto-placental compartment is affected.

    In conclusion: Pregnancy seriously affects the maternal thyroid hormone status. Despite an unchanged thyroidal production of T4, all maternal T4 tissue levels are decreased. Less T4 is available for the mother because of the transport of T4 to the feto-placental compartment. Indirectly this results in a T3-deficiency in most maternal organs. During marginal iodine deficiency and maternal hypothyroidism the transport of maternal T4 to the feto-placental compartment is diminished, whereas during marginal iodine deficiency the availability of iodine for fetal thyroid hormone syn-thesis is also decreased. Eventually this can result in impaired development of the fetal central nervous system.

    Van geboorte tot slacht in een hok
    Vermeer, H. ; Plagge, G. ; Binnendijk, G. ; Backus, G. - \ 1997
    Praktijkonderzoek varkenshouderij 11 (1997)1. - ISSN 1382-0346 - p. 4 - 5.
    huisvesting, dieren - dierhouderij - dierenwelzijn - geboorte - biggen - productiviteit - rentabiliteit - slachtgewicht - spenen - animal housing - animal husbandry - animal welfare - birth - piglets - productivity - profitability - slaughter weight - weaning
    De technische resultaten van varkens die van geboorte tot slacht niet worden verplaatst en gemengd zijn beter dan die van varkens die tweemaal verplaatst en eenmaal gemengd worden. Het laatste is in de praktijk gebruikelijk.
    Lammersterfte gedaald door aanpassingen Low-inputsysteem
    Boer, J. de - \ 1997
    Praktijkonderzoek Rundvee, Schapen en Paarden. Praktijkonderzoek 10 (1997)5. - ISSN 1386-8470 - p. 30 - 32.
    geboorte - schapen - lammeren - groei - ontwikkeling - extensieve landbouw - birth - sheep - lambs - growth - development - extensive farming
    De aanpassingen in het Low-inputsysteem die halverwege de aflamperiode van 1996 zijn ingevoerd zijn in 1997 verder verfijnd. De aanpassingen rondom aflammeren zijn bijzonder effectief. Dit jaar is de sterfte teruggelopen tot 12,1%. Het sterftepercentage is gelijk aan het landelijk gemiddelde.
    Sterftepercentage bij aflammen 'Low-input systeem' nog te hoog
    Boer, J. de - \ 1996
    Praktijkonderzoek Rundvee, Schapen en Paarden. Praktijkonderzoek 9 (1996)5. - ISSN 1386-8470 - p. 30 - 33.
    geboorte - ontwikkeling - groei - lammeren - massa - gewicht - voedergrassen - birth - development - growth - lambs - mass - weight - fodder grasses
    De verwachting was dat door een evenrediger leeftijdsopbouw en het verlagen van het geboortegewicht door het sturen van het grasaanbod de sterfte met 5 tot 8% verlaagd kon worden. Dit doel is niet gerealiseerd.
    Gezondheidsregistratie op MDM-bedrijven
    Veling, J. - \ 1996
    Praktijkonderzoek Rundvee, Schapen en Paarden. Praktijkonderzoek 9 (1996)2. - ISSN 1386-8470 - p. 19 - 20.
    geboorte - melkvee - melkveehouderij - ontwikkeling - landbouwbedrijven - vruchtbaarheid - groei - diergeneeskunde - jonge dieren - bedrijfsinformatiesystemen - birth - dairy cattle - dairy farming - development - farms - fertility - growth - veterinary science - young animals - management information systems
    Vanaf voorjaar 1992 is gestart met een veterinair begeleidingssysteem toegespitst op de MDM-bedrijven.
    Het gebruik van Prostaglandine-FZalpha na werpen
    Loo, D. van de - \ 1995
    Praktijkonderzoek varkenshouderij 9 (1995)6. - ISSN 1382-0346 - p. 24 - 24.
    geboorte - vruchtbaarheid - oestrus - prostacycline - prostaglandinen - zeugen - birth - fertility - oestrus - prostacyclin - prostaglandins - sows
    Prostaglandine-FZalpha, zoals Dinolytice, Ilirene, Planatee en Prosolvine wordt in de Nederlandse varkenshouderij toegepast om geboorten te synchroniseren. Daarnaast zou het gebruik van Prostaglandine-F2alpha na het werpen de baarmoeder sneller en beter schoon krijgen. Dit zou een positief effect hebben op de vruchtbaarheid bij de volgende worp.
    Bedrijfservaringen met het opwekken van geboorten
    Loo, D. van de - \ 1995
    Praktijkonderzoek varkenshouderij 9 (1995)6. - ISSN 1382-0346 - p. 8 - 9.
    dierhouderij - geboorte - productiviteit - rentabiliteit - prostacycline - prostaglandinen - animal husbandry - birth - productivity - profitability - prostacyclin - prostaglandins
    Prostaglandine-F2alpha (verkocht onder de merknamen Dinolytice, Ilirene, Planatee, Prosolvine etcetera) wordt op sommige varkensbedrijven toegepast om geboorten te synchroniseren. Op het Varkensproefbedrijf te Sterksel zijn bedrijfservaringen opgedaanmet Dinolytice. Dit blijkt goed toepasbaar om de geboorte op te wekken.
    Aparte kraam- en dek/drachtbedrijven
    Bens, P. ; Backus, G. - \ 1995
    Praktijkonderzoek varkenshouderij 9 (1995)3. - ISSN 1382-0346 - p. 4 - 5.
    diervoedering - geboorte - veredelingsmethoden - biggen - zeugen - gespecialiseerde landbouw - jonge dieren - animal feeding - birth - breeding methods - piglets - sows - specialized farming - young animals
    De biggenproductie vindt in Nederland plaats op vermeerderingsbedrijven die de biggen afleveren op 25 kg. Het vermeerderingsbedrijf kan gesplitst worden in een dek/dracht bedrijf en een apart kraam/opfokbedrijf.
    Toename geboorteproblemen bij Blonde kalveren uit zwartbonte koeien
    Hanekamp, W.J.A. - \ 1995
    Praktijkonderzoek / Praktijkonderzoek Rundvee, Schapen en Paarden (PR), Waiboerhoeve 8 (1995)6. - ISSN 0921-8874 - p. 35 - 36.
    dierhouderij - geboorte - stieren (bulls) - kalveren - melkvee - melkveehouderij - massa - productiviteit - rentabiliteit - gewicht - animal husbandry - birth - bulls - calves - dairy cattle - dairy farming - mass - productivity - profitability - weight
    Implanteren van Blonde d'Aquitaine embryo's in zwartbonte melkkoeien geeft ten opzichte van koeien die geonsemineerd zijn met een zwartbonte of Piemontese stier een langere draagtijd en meer moeilijke geboortes.
    'Low-input' schapen
    Boer, J. de; Schans, F.C. van der - \ 1995
    Praktijkonderzoek / Praktijkonderzoek Rundvee, Schapen en Paarden (PR), Waiboerhoeve 8 (1995)5. - ISSN 0921-8874 - p. 1 - 3.
    dierhouderij - geboorte - veredelingsmethoden - tussenkalftijd - ontwikkeling - embryotransplantatie - ooien - groei - eiceltransplantatie - zwangerschap - productiviteit - rentabiliteit - animal husbandry - birth - breeding methods - calving interval - development - embryo transfer - ewes - growth - ova transfer - pregnancy - productivity - profitability
    Op het Low Input Schapenbedrijf van de Waiboerhoeve ligt het dek- en aflamseizoen enkele maanden later dan op de traditionele schapenbedrijven.
    Poliklinische kraamafdelingen in combinatie met zoogafdelingen
    Hoofs, A.I.J. - \ 1994
    Rosmalen : Praktijkonderzoek varkenshouderij (Proefverslag / Proefstation voor de Varkenshouderij P1.100) - 56
    geboorte - ontwikkeling - kraamstallen - groei - biggen - varkens - zogen - birth - development - farrowing houses - growth - piglets - pigs - suckling
    Poliklinische kraamafdelingen in combinatie met zoogafdelingen: betere productieresultaten maar nu nog te duur
    Hoofs, A. - \ 1994
    Praktijkonderzoek varkenshouderij 8 (1994)1. - ISSN 1382-0346 - p. 9 - 13.
    geboorte - ontwikkeling - kraamstallen - groei - biggen - varkens - zogen - birth - development - farrowing houses - growth - piglets - pigs - suckling
    Er is nog duidelijk verbetering mogelijk ten aanzien van uitval en gezondheid van de biggen gedurende de zoogperiode. Uit het onderzoek naar de perspectieven van poliklinische kraamafdelingen (Profiboxen) blijkt dat deze verbetering vooral gedurende de eerste uren (dag) na de geboorte van de biggen behaald moet worden.
    Toedienen van antistoffen aan biggen met een laag geboortegewicht door injectie van bloedserum verlaagt de uitval niet
    Plagge, G. - \ 1993
    Praktijkonderzoek varkenshouderij 7 (1993)1. - ISSN 1382-0346 - p. 12 - 13.
    dierhouderij - geboorte - bloedtransfusie - massa - biggen - productiviteit - rentabiliteit - diergeneeskunde - gewicht - animal husbandry - birth - blood transfusion - mass - piglets - productivity - profitability - veterinary science - weight
    Biggen met een laag geboortegewicht hebben een verhoogde kans op sterfte in de eerste dagen na de geboorte. Het toedienen van extra antistoffen kort na de geboorte door middel van injectie van bloedserum, afkomstig van een oudere zeug van het eigen bedrijf, resulteerde niet in een verlaging van de uitval.
    Eenmaal per jaar aflammeren van Flevolanders in juli voor melkveehouders aantrekkelijk alternatief
    Boer, J. de - \ 1992
    Praktijkonderzoek / Praktijkonderzoek Rundvee, Schapen en Paarden (PR), Waiboerhoeve 5 (1992)5. - ISSN 0921-8874 - p. 24 - 27.
    geboorte - melkvee - melkveehouderij - ooien - agrarische bedrijfsvoering - begrazing - innovaties - schapenrassen - birth - dairy cattle - dairy farming - ewes - farm management - grazing - innovations - sheep breeds
    Op melkveebedrijven is in het algemeen in het najaar veel gras over wanneer de koeien opgestald worden. Dit gras kan door schapen en lammeren tot waarde worden gebracht.
    Winst poliklinisch werpen in eerste uren
    Hoofs, A. - \ 1991
    Praktijkonderzoek varkenshouderij 5 (1991)2. - ISSN 1382-0346 - p. 6 - 7.
    geboorte - kraamstallen - biggen - varkens - birth - farrowing houses - piglets - pigs
    Het creëren van een optimale opvang van de pasgeboren biggen in de eerste levensuren is vermoedelijk de grote kracht van poliklinisch werpen. Geen tocht bij de biggen en warmtetoevoer aan de biggen zijn twee aspecten die hierbij van wezenlijk belang zijn.
    Profibox bewijst zich bij Abortus Blauw
    Hoofs, A. - \ 1991
    Praktijkonderzoek varkenshouderij 5 (1991)3. - ISSN 1382-0346 - p. 7 - 9.
    varkens - kraamstallen - zeugen - diergeneeskunde - geboorte - virusziekten - abortus - opgewekte abortus - pigs - farrowing houses - sows - veterinary science - birth - viral diseases - abortion - induced abortion
    Vooruitgang in de technische resultaten is nog mogelijk tijdens de zoogperiode. Dit blijkt uit de resultaten die in 1990 behaald zijn met de Profibox bij in het algemeen gezonde dieren. De winst moet voornamelijk in de eerste dag na de geboorte behaald worden. Een optimale opvang van de pasgeboren biggen is hierbij essentieel (warmte en geen tocht).
    Poliklinisch werpen alleen bruikbaar met individuele zoogopfokhokken
    Hoofs, A. - \ 1990
    Praktijkonderzoek varkenshouderij 4 (1990)6. - ISSN 1382-0346 - p. 7 - 9.
    geboorte - kraamstallen - varkens - zeugen - birth - farrowing houses - pigs - sows
    Groepshuisvesting van zogende zeugen met biggen direct na poliklinisch werpen leidt op dit moment tot een te hoog uitvalspercentage van de biggen. Dit blijkt uit de eerste resultaten van een nog lopend onderzoek op het Varkensproefbedrijf in Sterksel
    Zwangerschapsverlof voor boerinnen en tuindersvrouwen
    Blom, U.P. ; Hoek, J.M. van den - \ 1989
    Den Haag : LEI (Onderzoekverslag / Landbouw-Economisch Instituut 51) - ISBN 9789052420226 - 82
    sociale klassen - boeren - bevruchting - zwangerschap - geboorte - sociale wetgeving - sociaal beleid - vrouwen - landbouw - tuinbouw - Nederland - vakanties - vrije tijd - vrije uren - social classes - farmers - fertilization - pregnancy - birth - social legislation - social policy - women - agriculture - horticulture - Netherlands - holidays - leisure - free time
    Onderzoek in 2 fasen naar de behoefte aan en de mogelijkheden tot zwangerschaps- en bevallingsverlof bij meewerkende echtgenotes in de agrarische sector: in de 1e fase zijn via een schriftelijke enquete onder 515 jonge meewerkende echtgenotes gegevens verzameld over de mate van meewerken op het agrarisch bedrijf rond de bevalling en de mening over een zwangerschapsverlofregeling, en als 2e fase zijn 50 vrouwen hiervan mondeling nader ondervraagd naar problemen en behoeften
    Poliklinisch werpen van zeugen
    Broekman, J.A.C. - \ 1989
    Praktijkonderzoek varkenshouderij 3 (1989)4. - ISSN 1382-0346 - p. 20 - 22.
    geboorte - zeugen - birth - sows
    Bij poliklinisch werpen maak je gebruik vanaparte kraamhokken. Het werpen vindt plaatsin een speciaal ingerichte en gecontroleerdeomgeving. Dit geldt voor stalklimaat, hygiëne,hokinrichting en controle.
    Eerste ervaringen met het poliklinisch werpen
    Hoofs, A. ; Bardoel, H. - \ 1988
    Praktijkonderzoek varkenshouderij 2 (1988)5. - ISSN 1382-0346 - p. 14 - 16.
    geboorte - kraamstallen - varkens - zeugen - birth - farrowing houses - pigs - sows
    Door het lage uitvalspercentage en een goede groei, leidt het poliklinisch werpen voor de gehele zoogperiode tot betere technische resultaten en minder veterinaire behandelingen.
    Invloed van de afkalfdatum op de voedervoorziening melkvee : berekeningen in het kader van een studie naar de bedrijfseconomische gevolgen van verschillende afkalfdata
    Mandersloot, F. - \ 1986
    Lelystad : Proefstation voor de Rundveehouderij, Schapenhouderij enPaardenhouderij (Rapport / Proefstation voor de Rundveehouderij, Schapenhouderij en Paardenhouderij P.R. 102) - 121
    diervoedering - geboorte - melkvee - melkveehouderij - agrarische bedrijfsvoering - animal feeding - birth - dairy cattle - dairy farming - farm management
    Naast het onregelmatig aanvoerpatroon van de melk naar de zuivelindustrie dreigt de aanvoer door de invoering van de superheffing nog sterker naar de zomerperiode te verschuiven. Om dit tegen te gaan geeft een deel van de zuivelindustrie prijstoeslagen op de wintermelk. Om zo veel mogelijk van de toeslagen te profiteren kan men verschuivingen in het afkalfpatroon overwegen, afhankelijk van de hoogte van de toeslag, de produktiekosten voor melk bij verschillende afkalfmaanden en de extra kosten t.g.v. de uitgevoerde verschuiving van afkalfpatroon. In deze studie wordt, in aansluiting op ander onderzoek naar deze factoren, de gehele voedervoorziening voor een aantal afkalfmaanden nagegaan, waarbij gebruik is gemaakt van graslandgebruiksmodellen en koemodellen
    Dystocia in dairy cattle breeding [:with special attention to sire evaluation for categorical traits]
    Meijering, A. - \ 1986
    Landbouwhogeschool Wageningen. Promotor(en): R.D. Politiek; E.W. Brascamp. - Wageningen : Meijering - 179
    dierveredeling - geboorte - melkvee - melkveehouderij - verbetering - partus - pathologie - weerstand - diergeneeskunde - animal breeding - birth - dairy cattle - dairy farming - improvement - parturition - pathology - resistance - veterinary science
    Field data recorded in the early seventies showed that dystocia (calving difficulty) in the main Dutch cattle breeds occurred at a rate of 15-17% in heifers and 5-6% in cows. Corresponding stillbirth rates were 9-12% and 2.5-3.5% respectively. In the sixties and seventies many research papers on dystocia and stillbirth appeared which dealt with frequencies in various breeds and breed crosses, causes, associated factors, economic consequences and factors with systematic impact. These papers are reviewed in chapter 1. Important conclusions can be summarized as follows.

    1. Dystocia is a major cause of stillbirth: 40 to 60% of the stillbirth cases encountered in field data are associated with dystocia. Additional negative consequences of dystocia are increased labour and veterinary costs, reduced fertility and milk yield, and an increased culling rate.

    2. First-calf heifers and older cows differ both in frequency and in cause of dystocia. The frequency of calving difficulty in eifers is generally three to four times as high as in cows. In heifers, the most frequent cause of dystocia is feto-pelvic-incompatibility, i.e. a disproportion between the size of the calf and the pelvic dimensions of its dam. Deviations in the presentation of the calf account for a second substantial part. In cows, feto-pelvic- incompatibility is encountered less frequently, whereas other causes such as weak labour, uterine torsion and insufficient cervical dilation are rela tively more important.

    3. Within parity, the probability of dystocia is positively related, i.e. increases, with the weight and dimensions of the calf at birth. The (phenotypic) relationships show a threshold character, i.e. the probability of dystocia increases strongly when the size of the calf exceeds a certain threshold value. The probability of dystocia is positively related with gestation length as well, probably mediated by calf size. With respect to the dimensions of the pelvic inlet of the dam a negative relationship is found. The size of the calf and the dimensions of the dam's pelvic inlet are the basic elements in feto-pelvic-incompatibility.

    4. Apart from parity of the dam, factors with systematic influence on the frequency of calving difficulty are sex of calf and season of calving. In male calves the frequency is about twice as high as in females which is mainly due to the larger average size of the males. In the North-Western part of Europe dystocia tends to be more frequent in autumn and early winter than in spring and summer. This seasonal pattern is often, but not always, found to be associated with a seasonal fluctuation in birth weight.

    5. Dystocia, stillbirth, as well as the associated calving traits birth weight and gestation length, are influenced by the genotype of both the calf and its dam, which results in a complicated genetic model. With a view to sire selection, the influence of the genotype of the calf is generally referred to as sire-of-calf effect, direct genetic effect or mate effect. Similary, the influence of the genotype of the dam is referred to as maternal-grandsire effect or indirect genetic effect. The mode of action of the direct genetic effect is supposed to be relatively simple: the sire transfers genes to the calf which are expressed in the calf phenotype (e.g. size, gestation length) which may affect the ease of birth. The maternal grandsire is supposed to act upon calving traits in a more complicated way. First, the maternal-grandsire effect contains a direct genetic component since the sire of the dam also transfers genes to the calf. This part of the maternal-grandsire effect is similar to the sire-of- calf effect but half of the size. Besides, the maternal grandsire may in fluence calving traits by transferring genes to the dam which actual ly find expression in the dam, for instance in the pelvic dimensions or by means of a maternal effect on the size of the calf. This is referred to as the maternal genetic component. The direct and mater nal genetic component are suspected to interact. Estimates of rele vant parameters are summarized in tables III to VI of chapter 1.

    6. Difficulties are encountered in the genetic-statistical analysis of data on ease of calving and stillbirth because of their categorical nature. At least in theory, the non-normality, the location dependent variance and the non-additivity of-effects involved reduce the value of the usual estimation and prediction techniques based on the linear model and on normality of traits.

    In the sixties and seventies AI-organisations in the Netherlands gradually started to apply the results from the research on calving traits, those on the effect of parity and the sire-of-calf effect in particular, by introducing a so-called heifer-bull-programme. This involves the testing of young bulls for direct genetic effect on calving traits and the recommendation of low-risk bulls with respect to dystocia and stillbirth for heifer matings. At that time, the data collection procedure was not uniform over AI-organisations, whilst the method of sire evaluation was not optimized. At the end of the seventies the research project which underlies this thesis was started, with two main objectives:

    1. Optimization of the heifer-bull-programme including data collection and sire evaluation.

    2. Examination of alternative sire-selection strategies to reduce dystocia, with emphasis on the impact of maternal genetic effects and direct maternal-interaction.

    Sire evaluation for categorical traits

    The optimization of data collection within the framework of the heiferbull-programme is no subject-matter of this thesis, but one of the main results, a mark-sense card for birth recording which is used nation-wide now, is shown as figure 1 in chapter 4. In the optimization of sire evaluation, emphasis was laid on a comparison between the method of Best Linear Unbiased Prediction (BLUP), which has optimal properties with normally distributed data, and a pseudo- Bayesian nonlinear method of sire evaluation for categorical variates based on the "threshold', concept, when applied to binary and ordered tetrachotomous reponses.

    Chapter 2 refers to a comparison of these two methods with simulated data with a family structure consisting of half-sib groups of equal or unequal size. Simulations were done at varying levels of heritability and incidences of the binary trait. The methods were compared for their ability to elicit responses to truncation selection. The nonlinear procedure, which is theoretically more appealing, proved to be superior in a mixed model setting when the responses were binary, the layout was highly unbalanced, heritability was moderate to high and the incidence was below 25%. When a one-way model was tenable or when responses were tetrachotomous, the results by both methods were very similar.

    In a similar simulation study, it was examined whether the incorporation of heteroscedastic residual variance into the BLUP-model would improve the sire-ranking ability of this method with categorical variates (chapter 3). Such an "adjustment" was proposed in the literature. The results indicated however that the ability of BLUP to rank sires correctly for categorical traits is impaired by adjustments of this kind, particulary when responses are binary, in spite of a reduction in apparent prediction error variance. This is consistent with deductions from the theory of threshold models.

    In a third study (chapter 4) BLUP, with homogeneous residual variance, and the nonlinear method were compared in estimating genetic merits for ease of calving and stillbirth under field conditions, i.e. with a data sample from the birth recording programme in the Netherlands. Since only minor differences in sire ranking were observed between the two methods, it is concluded that there is no clear advantage in applying the nonlinear prcedure, which entails more complicated and time consuming computations than BLUP, in sire evaluation for dystocia and stillbirth.

    The results of these studies lead to the conclusion that BLUP with homogeneous residual variance, which is a standard method of sire evaluation for dairy traits in many countries, is fairly robust against the departures from normality and linearity arising with categorical data. Because of the computational expenses involved in the nonlinear procedure, particulary with large data sets, an appropriate BLUP-model which should at least correct for parity, sex of calf, herd and season of calving is advised for the evaluation of sires for dystocia and stillbirth in the Netherlands.

    Sire selection for dystocia

    Sire selection for direct genetic effect on dystocia may not be very appealing under the Dutch market conditions because dystocia is very highly cor related, in the genetic sense, with birth weight (r g ≈0.9) as shown in chapter 4. A reduction in level of dystocia by this type of selection would almost inevitably entail a reduction in birth weight which will lower the proceeds from the sale of young calves from the dairy farm. Since maternal effects are assumed to be involved in ease of birth, selection for traits contributing to maternal calving performance might be an alternative. With the exception of the pelvic inlet dimensions, which are difficult to measure and hence unsuitable for al large scale progeny test, such traits had not been identified. Chapter 5 refers to a study into the phenotypic association between ease of calving and a number of, mainly morphologic, dam traits in Holstein, Dutch Red and White and Dutch Friesian heifers. However, the only factor clearly associated with ease of calving was the size of the calf.

    Since the attempt to identify dam traits with significant effect on calving performance failed, alternatives left apart from the heifer- bull-programme, are selection for direct genetic effect, with the disadvantage discussed, or selection for maternal-grandsire effect. Because of the suspected negative covariance between the direct and maternal genetic effects, it was felt necessary to examine the sign and the size of the covariance between the direct genetic effect and the maternal-grandsire effect. This necessity was underlined by a reluctancy among herdsmen to use the low-risk bulls identified in the heifer-bull-programme because they suspected that these bulls would sire small calves, which develop into small heifers and which run an increased risk of dystocia. In chapter 6 this hypothesis is examined in a two-way sireselection trial with purebred Holstein, Dutch Red and White and Dutch Friesian cattle. Although the results were not entirely consistent over breeds, this study yielded additional evidence that direct and maternal-grandsire merits for ease of birth as well as for birth weight and gestation length are correlated positively. It was conjectured that the maternal- grandsire effect on ease of birth is dominated by direct inheritance of calf size. This conclusion implies that selection of sires for ease of birth of their progeny as calves is expected to yield a favourable response with respect to the ease of calving of their daughters and vice versa.

    Selection programmes

    In the final chapter, the monetary (discounted) returns from three schemes of breeding bull selection for calving traits (score for calving ease, birth weight, gestation length), viz. identification of lowrisk bulls for heifer matings among breeding bulls selected for dairy traits, selection on direct genetic merit for calving traits in addition to selection for dairy traits and selection on maternal-grandsire merit for calving traits in addition to selection for dairy traits are estimated for several calf price levels and incidences of dystocia. The first scheme, i.e. the heifer-bull-programme, proved to increase the returns from a breeding programme in dairy cattle, particularly when the incidence of dystocia or the calf price is high. Within such a scheme sire evaluation for birth weight and gestation length in addition to the evaluation for a score for calving ease contributes only marginally to the accuracy of low-risk-bull identification, at least when the latter is based on about 200 progeny per sire. Selection indices for direct genetic or maternal-grandsire effects on calving traits reduced the incidence of dystocia only at low calf prices (upto about Dfl 5.00 per kg). In the normal calf price range in the Netherlands (Dfl 7.50 - Dfl 15.00 per kg) either type of selection, if advisable at all, should be for an increase in birth weight in spite of a corresponding rise in incidence of dystocia. This is due to the highly positive genetic correlation between dystocia and birth weight. Because of a reduced intensity of selection for dairy traits, the impact of additional selection for birth weight on the total returns from the selection of breeding bulls in dairy cattle is either negative, or only marginally positive however. Consequently, the heifer-bull-programme is the most attractive breeding strategy to reduce dystocia.

    Correctiefactoren om het geboortegewicht van biggen te schatten op basis van het gewicht 1 of 2 dagen na de geboortedag
    Merks, J.W.M. ; Buiting, G.A.J. - \ 1985
    Zeist : IVO (I.V.O.-rapport / Instituut voor Veeteeltkundig Onderzoek "Schoonoord" no. B-269) - 20
    geboorte - massa - biggen - gewicht - birth - mass - piglets - weight
    De resultaten geven aan dat het geboortegewicht op basis van het 1e-dags gewicht geschat kan worden met de factor 0,93, terwijl voor de schatting op basis van het 2e-dags gewicht de factor 0,85 voorgesteld wordt. Aangezien de nauwkeurigheid van de schatting op basis van het 1e-dags gewicht 92% bedraagt, terwijl de nauwkeurigheid voor de schatting op basis van het 2e-dags gewicht 82% bedraagt, dient het gebruik van het 2e-dags gewicht zoveel mogelijk beperkt te blijven
    Vroege drachtigheidsdiagnose bij geiten d.m.v. progesteronmeting in de melk
    Koops, W. ; Wiel, D.F.M. van de; Adrichem Boogaart, D.H. van - \ 1983
    Zeist : I.V.O. (Rapport / Instituut voor Veeteeltkundig Onderzoek "Schoonoord" no. B-210) - 31
    dierlijke producten - geboorte - chemische samenstelling - zuivelindustrie - embryotransplantatie - bevruchting - geiten - ingrediënten - melkproducten - eiceltransplantatie - zwangerschap - progesteron - diergeneeskunde - animal products - birth - chemical composition - dairy industry - embryo transfer - fertilization - goats - ingredients - milk products - ova transfer - pregnancy - progesterone - veterinary science
    Verslag van een onderzoek waarbij een radio-immunologische bepaling (met behulp van "zwaar water", 3H) van het progesterongehalte werd uitgetest in de eerste 30 dagen na de bronst
    Geboorten, zuigelingenvoeding en zuigelingensterfte in hun regionale verscheidenheid in de 19de eeuw
    Hofstee, E.W. - \ 1983
    Bevolking en Gezin 1983 (1983)Supplement. - ISSN 0772-764X - p. 7 - 60.
    geboorte - zuigelingensterfte - demografie - zuigelingenvoeding - regio's - borstvoeding - vruchtbaarheid - birth - infant mortality - demography - infant nutrition - regions - breast feeding - fertility
    Onderzoek naar de de ontwikkeling van de zuigelingen- en kindersterfte in België en Nederland in de 19de eeuw. Tevens wordt gepoogd om tot een nader inzicht te komen in de demografische betekenis van de borstvoeding in Nederland vóór de periode van de moderne geboortendaling.
    Schatting van paternaal- en maternaal-genetische parameters voor geboorte-kenmerken met behulp van Friese geboorte-registratiegegevens
    Meijering, A. - \ 1981
    Zeist : Instituut voor Veeteeltkundig Onderzoek "Schoonoord" (Rapport / Instituut voor Veeteeltkundig Onderzoek "Schoonoord" no. B-175) - 19
    geboorte - rundvee - nederland - friesland - birth - cattle - netherlands - friesland
    Proefproject geboorteregistratie
    Meijering, A. ; Eldik, P. van - \ 1981
    Zeist : IVO (Rapport / Instituut voor Veeteeltkundig Onderzoek "Schoonoord" no. B-165)
    geboorte - rundvee - nederland - partus - pathologie - diergeneeskunde - birth - cattle - netherlands - parturition - pathology - veterinary science
    Aflamproblemen bij ooien van verschillende paringstypen
    Visscher, A.H. ; Lohuyzen, M.G. van - \ 1981
    Zeist : I.V.O. (Rapport / Instituut voor Veeteeltkundig Onderzoek "Schoonoord" no. B-186) - 57
    geboorte - partus - pathologie - schapen - diergeneeskunde - birth - parturition - pathology - sheep - veterinary science
    Retentio secundinarum bij het rund
    Anonymous, - \ 1981
    Den Haag : T.N.O. (Rapport / Instituut voor Veeteeltkundig Onderzoek "Schoonoord" no. B-187) - 53
    geboorte - rundvee - nederland - placenta - diergeneeskunde - birth - cattle - netherlands - placenta - veterinary science
    Gebruikskruising gezien uit het oogpunt van geboortemoeilijkheden
    Meijering, A. ; Bergstroem, P.L. - \ 1979
    Zeist : I.V.O. (Rapport / Instituut voor veeteeltkundig onderzoek 'Schoonoord' No. B-150) - 53
    vleesvee - geboorte - rundvee - kruisingsfokkerij - beef cattle - birth - cattle - crossbreeding
    Kalversterfte en afkalfpatroon
    Anonymous, - \ 1979
    Wageningen : Pudoc (Literatuurlijst / Centrum voor Landbouwpublikaties en Landbouwdocumentatie no. 4311)
    bibliografieën - geboorte - rundvee - bibliographies - birth - cattle
    Onderzoek naar factoren die het geboorteverloop bij runderen beinvloeden (Pilot - studies)
    Meijering, A. ; Jansen, A.A.M. ; Postma, A. - \ 1978
    Zeist : I.V.O. (Rapport / Instituut voor veeteeltkundig onderzoek "Schoonoord" no. C-357) - 27
    geboorte - rundvee - birth - cattle
    Het seizoen van afkalven van rundvee
    Anonymous, - \ 1977
    Wageningen : Pudoc (Literatuurlijst / Centrum voor landbouwpublikaties en landbouwdocumentatie no. 4074)
    bibliografieën - geboorte - rundvee - pathologie - zwangerschap - diergeneeskunde - bibliographies - birth - cattle - pathology - pregnancy - veterinary science
    Het afkalfpatroon in de Nederlandse melkveehouderij
    Boer, P.B. de - \ 1977
    Lelystad : Proefstation voor de Rundveehouderij (Publikatie / Proefstation voor de Rundveehouderij 9) - 87
    geboorte - melkvee - melkveehouderij - rundvee - agrarische bedrijfsvoering - nederland - birth - dairy cattle - dairy farming - cattle - farm management - netherlands
    In dit verslag is de geschetste problematiek geonventariseerd en geanalyseerd. Tevens is nagegaan of dit afkalfpatroon voor de rundveehouderij zelf nog wel het aantrekkelijkst is en of van een gelijkmatig afkalfpatroon voor de productieketen in zijn geheel belangrijke voordelen te verwachten zijn.
    Induction of bovine parturition with flumentasone and estrogens and its effect on the incidence of retained placenta and milkfever
    Osinga, A. ; Hazeleger, W. ; Bootsma, A. ; Peynenburg, T. ; Boer, D.J. den; Dijke, J.J. van - \ 1977
    Wageningen : L.H. - 8
    geboorte - rundvee - diergeneeskunde - melkziekte - pathologie - partus - afwijkingen - aangeboren afwijkingen - birth - cattle - veterinary science - parturient paresis - pathology - parturition - abnormalities - congenital abnormalities
    Drachtigheidsdiagnose bij het varken : toepassing van de vaginabiopsie-methode
    Arts, J.A.M. ; Brake, J.H.A. te; Cromwijk, W.A.J. - \ 1976
    Zeist : I.V.O. (Rapport / Instituut voor veeteeltkundig onderzoek Schoonoord no. B-143) - 17
    geboorte - embryotransplantatie - bevruchting - eiceltransplantatie - varkens - zwangerschap - diergeneeskunde - birth - embryo transfer - fertilization - ova transfer - pigs - pregnancy - veterinary science
    Het melken van koeien voor het afkalven
    Maatje, K. ; Dijkman, A.J. ; Beuzel, J.H. - \ 1976
    Zeist : I.V.O. (Rapport / Instituut voor veeteeltkundig onderzoek "Schoonoord" C, no. 284) - 7
    geboorte - rundvee - lactatie - melkklieren - melkkwaliteit - melksecretie - melkopbrengst - zogen - birth - cattle - lactation - mammary glands - milk quality - milk secretion - milk yield - suckling
    Orienterend onderzoek naar de preventie van afkalfmoeilijkheden bij M.R.IJ. - vaarzen door kruising met F.H. - en Herfordstieren en de geschiktheid voor vleesproduktie van de kruisingskalveren
    Laurijsen, H.A.J. ; Oldenbroek, J.K. ; Rooij, J. de - \ 1975
    Zeist : I.V.O. (Rapport / Instituut voor veeteeltkundig onderzoek "Schoonoord" C-275) - 9
    dierhouderij - geboorte - rundvee - kruisingsfokkerij - vlees - vleeswaren - nederland - productiviteit - rentabiliteit - animal husbandry - birth - cattle - crossbreeding - meat - meat products - netherlands - productivity - profitability
    Oestrogen excretion by the pregnant bovine and its relation with some characters of gestation and parturition
    Osinga, A. - \ 1970
    Wageningen University. Promotor(en): T. Stegenga. - Wageningen : Veenman - 89
    geboorte - rundvee - embryotransplantatie - eiceltransplantatie - zwangerschap - geslachtshormonen - birth - cattle - embryo transfer - ova transfer - pregnancy - sex hormones

    Previous studies indicated that genetic influences (e.g. sire of calf and breed of calf) as well as environmental influences (e.g. month of calving) are related to characters like birth weight, gestation length, ease of calving, stillbirth frequency and congenital defects. This research project was initiated to investigate the contribution of the circulating oestrogens in pregnant cows to some of these relationships. The above mentioned relationships could be accomplished via the hormonal mechanism. Variations in the parturition characteristics, therefore, might be related to quantitative variations in the hormonal equilibrium. The initiation of parturition is very much dependant on the calf's genotype, therefore this study concerns the oestrogenic hormones, for these hormones are predominantly produced by the foeto-placental unit, during gestation. In the pregnant cow progesterone seems to be produced only by maternal organs. No direct relationship with gestation is known for other steroids while peptide hormones are mainly produced by the maternal pituitary. The function of peptide hormones and of corticosteroids in the process of parturition has not been described in this study. From the available analytical methods, which were developed for the oestrogen analysis in human urine, methods were developed for the quantitative analysis of oestradiol-17αand oestrone in urine as well as faeces of pregnant cows. The urinary oestrogen excretion rate is expressed as the oestrogen/creatinine ratio (μg/g), because it is difficult to collect 24 hour urine samples of many experimental animals. The ratio between the oestrogen concentration and the creatinine concentration proved to be a little higher at night as a result of a significant circadian rhythm in the creatinine output.

    In order to study the applicability of the analytical method and the total variation in the urinary oestrogen excretion rate, within cows and between cows, two preliminary experiments were carried out during 1966, 1967 and 1968. In total 168 cows, from 4 experimental farms, were sampled regularly, 60 of these cows participated in both experiments during 2 consecutive pregnancies. In order to study the genetic influences on the oestrogen excretion rate, the material of experiment I included 21 and experiment II 41 sets of identical twins.

    All oestrogen/creatinine ratios had to be transformed to a square root, because the raw data deviated significantly from a normal distribution.

    Analysis of variance showed that the oestrogen/creatinine ratios as well as their standard deviations increased with the stage of gestation. Between the mean oestrogen excretion rates of cows, grouped together according to their herds, months of calving, birth weight of calves and breed crosses or pure breeds, differences were found within the stages of pregnancy.

    High heritability estimates were calculated from the data obtained from identical twins in the second experiment. High correlation coefficients could be calculated between the oestrogen excretion rates within cows of two consecutive pregnancies.

    In 10 normal and 11 induced parturitions (with flumethasone) the variation in the urinary oestrogen excretion rate was studied immediately before, during and after parturition. The urinary oestradiol-17αexcretion rate increases up to the last day before normal parturition and decreases within a few hours before parturition. Within two days after normal - as well as induced - parturition the urinary oestrogen excretion rate drops to such a low level that it cannot be estimated accurately enough by the applied analytical method. In induced parturitions a dramatic increase in the oestrogen excretion rate occurs between 12 hours after medication and the moment of parturition.

    In combination with balance-trials the ratio between oestrogens excreted in the faeces and in the urine was found to vary within animals from week to week and between animals. During 8 weeks 32 daily collections of urine and faeces from 4 cows were analysed. This experiment showed that at least 25 of the total oestrogens is excreted via the faecal route.

    In a specially designed experiment in one a.i.-centre, 5 groups of 25 cows each group pregnant to a bull, selected for producing a high or low incidence of stillbirths in heifers, showed a relationship between stillbirth frequency and urinary oestrogen excretion rate during pregnancy. Cows bred to bulls producing a high stillbirth frequency in heifers showed a low urinary oestrogen excretion rate at 260 days. It was concluded that a difficult calving, in which parturition proceeds slowly and lasts long, might be caused by a coincidence of a high birth weight of the calf and a low oestrogen excretion rate by the dam.

    Friesian cows, bred to a Charolais bull, frequently show a difficult parturition coinciding with a heavy calf. Therefore, in such cows a low urinary oestrogen excretion was anticipated.

    One animal of each pair of 6 identical Friesian twins was bred to a Charolais bull and the other was bred to a Friesian bull. The excretion of oestradiol-17αwas significantly lower in the cows bred to the Charolais bulls during the last three weeks of pregnancy than in the cows bred to the Friesian bulls. The excretion of oestrone was significantly lower in the cows bred to the Charolais bulls at 260 days after conception when compared to their twin sisters bred to Friesian bulls.

    Geboortegewicht van lammeren
    Anonymous, - \ 1969
    Wageningen : [s.n.] (Literatuurlijst / Centrum voor landbouwpublikaties en landbouwdocumentatie no. 3098)
    bibliografieën - geboorte - lammeren - massa - gewicht - bibliographies - birth - lambs - mass - weight
    Onderzoek naar het gewicht van ooien en de groei van lammeren
    Roeper, W.J.G. - \ 1967
    Gouda : [s.n.] - 5
    geboorte - karakteristieken - schapen - birth - characteristics - sheep
    Bedrijfstelevisie in een varkenskraamstal
    Poelma, H.R. - \ 1967
    Wageningen : [s.n.] (Mededeling / Instituut voor landbouwbedrijfsgebouwen no. 23) - 3
    geboorte - varkens - televisie - video-opnames - dierenwelzijn - huisvesting, dieren - birth - pigs - television - video recordings - animal welfare - animal housing
    Geboorteverloop en geboortemoeilijkheden bij rundvee
    Anonymous, - \ 1966
    Wageningen : [s.n.] (Literatuurlijst / Centrum voor landbouwpublikaties en landbouwdocumentatie no. 2778)
    bibliografieën - geboorte - rundvee - bibliographies - birth - cattle
    De invloed van de verdeeling der kalftijden over het jaar op de samenstelling van het melkvet, afkomstig van afzonderlijke boerderijen
    Dam, W. van - \ 1937
    's-Gravenhage : [s.n.] (Verslagen van landbouwkundige onderzoekingen no. 43,10) - 28
    dierlijke producten - geboorte - rundvee - vet - rauwe melk - vetgehalte - animal products - birth - cattle - fat - raw milk - fat content
    Vroegere onderzoekingen over R.M.W. - Getallen van botervet mede in verband met de vraag of gedeeltelijke verandering van den kalftijd van ons vee misschien zal kunnen leiden tot het verkrijgen van steviger boter
    Dam, W. van - \ 1936
    's-Gravenhage : [s.n.] (Verslagen van landbouwkundige onderzoekingen no. 42,3) - 10
    boterolie - geboorte - boter - rundvee - malsheid - textuur - vluchtige vetzuren - leeftijd bij eerste keer kalven - butter oil - birth - butter - cattle - tenderness - texture - volatile fatty acids - age at first calving
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