Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    '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.

    We have a manual that explains all the features 

    Current refinement(s):

    Records 1 - 20 / 38

    • help
    • print

      Print search results

    • export

      Export search results

    Check title to add to marked list
    Pilot selectief droogzetten op Dairy Campus
    Wemmenhove, H. - \ 2013
    V-focus 10 (2013)5. - ISSN 1574-1575 - p. 42 - 44.
    melkveehouderij - melkkoeien - gustperiode - antibiotica - dosering - celgetal - dairy farming - dairy cows - dry period - antibiotics - dosage - somatic cell count
    Op Dairy Campus in Leeuwarden is onderzoek gedaan naar het selectief droogzetten van koeien. Alleen koeien waarbij de laatste drie uitslagen van de MPR beneden 150.000 cellen/ml lagen kwamen in aanmerking om selectief te worden drooggezet.
    Droogzetten op kwartierniveau bespaart antibiotica
    Wemmenhove, H. ; Kuijt, A. ; Hamming, F. - \ 2013
    V-focus 10 (2013)5. - ISSN 1574-1575 - p. 46 - 47.
    melkveehouderij - melkkoeien - gustperiode - antibiotica - dosering - celgetal - melkklieren - uiers - dairy farming - dairy cows - dry period - antibiotics - dosage - somatic cell count - mammary glands - udders
    Naast het selectief droogzetten op koeniveau is er ook onderzoek gedaan naar selectief droogzetten op kwartierniveau. Door alleen kwartieren met een laag celgetal droog te zetten zonder antibiotica, is in deze pilot een besparing van 30 procent op droogzetpreperaten gerealiseerd zonder dat dit leidde tot het ontstaan van nieuwe mastitisgevallen tijdens de droogstand en in de eerste twee weken na afkalven. Voorwaarde is wel dat het koecelgetal op kwartierniveau kan worden gevolgd.
    Immunogenetics in dairy cattle : somatic cell count and natural antibody levels
    Wijga, S. - \ 2013
    Wageningen University. Promotor(en): Johan van Arendonk, co-promotor(en): Henk Bovenhuis; John Bastiaansen. - S.l. : s.n. - ISBN 9789461737274 - 178
    melkvee - melkkoeien - immunogenetica - celgetal - natuurlijke antilichamen - genomica - immunologie - genetica - dairy cattle - dairy cows - immunogenetics - somatic cell count - natural antibodies - genomics - immunology - genetics

    There remains is a lot to be learned about the interpretation of genetic parameters and the biology of disease resistance and SCS. This PhD thesis aimed to obtain additional insight in disease resistance and SCS by: 1) quantifying the impact of genetics on innate immunity, represented by natural antibodies (NAb), through estimation of heritabilities and genetic correlations; 2) identifying the genomic regions involved in SCS and NAb levels; 3) quantifying the impact of genetics on environmental sensitivity for SCS.

    Natural antibody levels are heritable with heritabilities ranging from 0.06 to 0.55 and in general, heritabilities for NAb isotypes were higher than heritabilities for total NAb levels, the latter making no distinction between isotypes. Genetic correlations suggest that isotypes IgA and IgM have a common genetic basis, but that the genetic basis for IgG1 differs from that for IgA or IgM. An additional genome-wide association study for NAb levels showed that information can be gained when total NAb levels are further subdivided into isotype levels. A region on chromosome 23 was significantly associated with genetic variation in isotype IgM levels. The bovine major histocompatibility complex (MHC) is located near this region, making this a region of candidate gene(s) involved in NAb expression in dairy cows both from a functional and positional perspective. Results from the study on genetic parameters and the genome-wide association study suggest that NAb isotypes may provide a better characterization of different elements of the immune response or immune competence and enable more effective decisions when breeding programs start to include innate immune parameters. A genome-wide association study was not only performed for NAb levels, but also for SCS. Relatively few associations, however, were found, which suggests that SCS is controlled by multiple loci, each with a relatively small effect, distributed across the genome.

    Somatic cell score is partly under genetic control, but is also affected by the environment. Sensitivity to respond to environmental factors, however, can have a genetic origin.

    Environmental factors can be divided into known and unknown factors, referred to as macro- and micro environment, respectively. Macro-environmental sensitivity can be expressed as genetic variation in the slope of a reaction norm, whereas micro-environmental sensitivity can be expressed as differences in residual variance that have a genetic origin. Both macro- and micro-environmental sensitivity were found for SCS and these sensitivities were positively correlated. Knowledge on both forms of sensitivity can aid in optimization of selection as correlations between the additive genetic variance in intercept, slope and environmental variance were all away from unity. Selection for reduced environmental sensitivity has the potential to reduce variability in animal performance due to environmental factors and herewith increase predictability of performance across and within environments.

    Knowledge on disease biology is important to fully understand the processes involved when selecting for increased disease resistance, as a better understanding enables a better prediction of the consequences. In this context, the general discussion involved the phenotype definition and statistical modeling, influence of maternal effects and genetic variation in the MHC region. The discussion contained three conclusions: 1) analyses of cell types (detailed phenotypes) rather than SCS can provide further insight in the genetic control of SCS and mastitis; 2) no evidence was found for maternal genetic effects on NAb levels in milk. Maternal environmental effects, however, could play a role in NAb levels; 3) genetic diversity in the MHC region is maintained by natural selection. Selective breeding and farm management practices may affect this genetic diversity, which could bring about negative effects on animal fitness, such as fertility problems. Selective breeding for specific MHC haplotypes may therefore impose a risk for negative effects on animal health.

    Genetic aspects of somatic cell count and udder health in the Italian Valle del Belice dairy sheep
    Riggio, V. - \ 2012
    Wageningen University. Promotor(en): Johan van Arendonk, co-promotor(en): Henk Bovenhuis; B. Portolano. - [S.l. : s.n. - ISBN 9789461732460 - 137
    ovis - schapen - schapenziekten - uiers - mastitis - celgetal - genetica - melkveehouderij - dierveredeling - italië - ovis - sheep - sheep diseases - udders - mastitis - somatic cell count - genetics - dairy farming - animal breeding - italy

    Mastitis is an inflammation of the udder, which leads to economic loss, mainly consisting of discarded milk, reduced milk production and quality, and increased health costs. Somatic cell count (SCC), and therefore somatic cell score (SCS), is widely used as indicator of mastitis. In this thesis, I focus on the genetic parameters of SCS as indicator of mastitis, and on the possibilities of using this trait for selection for mastitis resistance in the Valle del Belice dairy sheep.

    In Chapter 1, mastitis and SCS are defined and introduced. Chapter 2 deals with the estimation of genetic parameters for SCS and milk production traits in primiparous Valle del Belice ewes. Heritability estimates ranged from 0.09 to 0.14 for milk, fat and protein yields and contents. For SCS, the heritability of 0.14 was relatively high. SCS was genetically positively correlated to milk, fat and protein yields and contents. However, correlations were not extreme, so simultaneous improvement for milk yield and SCS seems possible. In Chapter 3, the level of SCC is included in a survival analysis to evaluate the effect of SCC on functional longevity. Results showed that an increase in SCC was associated with an increase in culling rate.Elevated SCC, therefore, play an indirect role in the culling decisions of Valle del Belice dairy sheep farmers, although, at present, farmers do not directly select for reduced SCC. In Chapter 4, the genetic parameters of the infection status and SCS, according to whether the samples were bacteria negative or positive are reported. Moreover, the impact of imperfect sensitivity and specificity on variance component estimates was investigated. The heritability was 0.10 for bacteria negative SCS, 0.03 for bacteria positive SCS, and 0.09 for infection status, on the liability scale. The genetic correlation between bacteria negative and bacteria positive SCS (0.62) suggests that they may be genetically different traits, confirming that SCSfrom healthy and infected animals should be analyzed separately. Moreover, a positive genetic correlation between bacteria negative SCS and liability to mastitis was found, suggesting that the approach of selecting animals for decreased SCS will help to reduce the prevalence of mastitis. The results also showed that the imperfect diagnosis of infection has an impact on estimated genetic parameters,which may reduce the efficiency of selection strategies aiming at distinguishing between bacteria negative and bacteria positive SCS. In Chapter 5, the diagnostic ability of SCCand California Mastitis Test (CMT) to detect intramammary infectionswas evaluated by using the Receiver-Operating Characteristic(ROC) curves, in order to identify a SCCthreshold that better discriminated healthy from infected udders. The results indicate that the CMT can only discriminate the udders infected from major pathogens. Nevertheless, in general SCS was the best indirect test for the bacteriological status of the udder.

    The final chapter explores and discusses the opportunities to use SCS as indicator of mastitis in a selection scheme to improve mastitis resistance for the Valle del Belice dairy sheep breed.

    Milk and milk products : annual report 2008 National Reference Laboratory
    Jacobs-Reitsma, W.F. ; Pol-Hofstad, I. - \ 2009
    Wageningen : RIKILT (Report / RIKILT, Institute of Food Safety 2009.010) - 33
    melk - melkproducten - rauwe melk - melk testen - celgetal - alkalisch fosfatase - fosfatasetest - kiemgetal - milk - milk products - raw milk - milk testing - somatic cell count - alkaline phosphatase - phosphatase test - bacterial count
    Suckling systems in calf rearing in organic dairy farming in the Netherlands
    Wagenaar, J.P. ; Langhout, D.J. - \ 2009
    melkveehouderij - zogen - spenen - speengewicht - melkkwaliteit - biologische landbouw - celgetal - dairy farming - suckling - weaning - weaning weight - milk quality - organic farming - somatic cell count
    In an on-farm experiment three calf rearing methods were compared: bucket feeding of milk replacer, bucket feeding of tank milk and suckling of mother or nurse cow up to three months of age. Aim was to determine whether the technical results of suckling systems in calf rearing were satisfactory. Calves reared in a suckling system reached significantly higher liveweights at weaning (90 days). Although the average growth rate between weaning and the age of 1 year did not differ significantly, liveweight at 1 year did still differ significantly. Compared to both bucket fed rearing groups, suckling did not have a significant effect on Somatic Cell Count (SCC) of mothers. Suckling systems in calf rearing in organic dairy production show satisfactory technical results. Calves have the potential to grow fast and no negative effect of suckling on SCC or general animal health were observed.
    Een veestapel in balans voorkomt een hoog celgetal
    Animal Sciences Group (ASG), - \ 2008
    melkveebedrijven - melkveehouderij - diergezondheid - celgetal - biologische landbouw - agrarische bedrijfsvoering - antibiotica - dierverzorging - dairy farms - dairy farming - animal health - somatic cell count - organic farming - farm management - antibiotics - care of animals
    Durks doelstelling is een bedrijfsvoering te ontwikkelen, waarbij hij het vee, de omstandigheden en het management zodanig op elkaar afstelt, dat antibioticagebruik tegen uierontsteking niet meer nodig is. Achterliggende visie is dat het gebruik van medicijnen beperkt moet blijven. Durk ontdekte dat de koeien na de omschakeling naar biologische bedrijfsvoering sterker waren geworden. De dieren herstelden sneller en gemakkelijker. Ook verliep het afkalven gemakkelijker en waren de kalveren vitaler en meer helder. Op basis hiervan zag Durk mogelijkheden om binnen zijn bedrijfssysteem het antibioticagebruik af te bouwen.
    Udder health: analysis of bloodcell dynamics in the PIR-DAP 'traffic light'
    Hooijer, G.A. ; Haas, Y. de; Horneman, M. - \ 2008
    Tijdschrift voor Diergeneeskunde 133 (2008)8. - ISSN 0040-7453 - p. 340 - 341.
    rundermastitis - celgetal - uiers - veterinaire praktijk voor grootvee - testen - bovine mastitis - somatic cell count - udders - large animal practice - testing
    PIR-Dap heeft in 2005 een hulpmiddel ontwikkeld die de verschuiving in het celgetal inzichtelijk maakt: het stoplicht. Binnen dit instrument wordt de veestapel percentagegewijs in drie groepen ingedeeld, namelijk het percentage dieren met een celgetal lager dan 100.000 (groen), het percentage met een celgetal tussen 100.00 en 200.000 (oranje) en het percentage met een celgetal hoger dan 200.000 (rood). Er wordt bij deze indeling geen onderscheid gemaakt tussen vaarzen en koeien. Dieren in deze drie categorieën worden als het gaat om uiergezondheid gezien als respectievelijk gezond, verdacht van besmetting en besmet
    Mammary Health: breeding
    Haas, Y. de; Jong, G. de; Lam, T.J.G.M. - \ 2008
    Tijdschrift voor Diergeneeskunde 133 (2008)11. - ISSN 0040-7453 - p. 464 - 468.
    diergezondheid - melkveehouderij - uiers - mastitis - celgetal - rassen (dieren) - verbetering van de veestapel - dierveredeling - animal health - dairy farming - udders - mastitis - somatic cell count - breeds - herd improvement - animal breeding - clinical mastitis - cows
    Uiergezondheidsproblemen kunnen ontstaan door een verstoring van de balans tussen de infectiedruk en de weerstand van dieren. Er zijn veel factoren van invloed op die weerstand, waarvan de erfelijke aanleg er een is. Fokkerij houdt zich bezig met de verbetering van deze erfelijke aanleg. Het is een bij uitstek op de toekomst gerichte activiteit vanwege het grote generatie-interval. Beslissingen die in de fokkerij worden genomen, bepalen de aanleg van de dieren die op termijn zullen produceren. Als is vastgesteld wat het fokdoel is, moeten de beste dieren voor die kenmerken worden geselecteerd als ouders van de toekomstige generatie. Weerstand tegen mastitis is voor een deel erfelijk bepaald en kan daarom worden verbeterd door middel van fokkerij. Hiervoor is het van belang dat er een “uiergezondheidsindex” is, waarin vijf kenmerken zijn verwerkt en worden gewogen. In dit artikel wordt duidelijk uiteengezet hoe deze zijn nut kan bewijzen
    Mastitis incidence and milk quality in organic dairy farms which use suckling systems in calf rearing.
    Wagenaar, J.P. ; Smolders, E.A.A. - \ 2008
    In: Proceedings of the second scientific conference of the ISOFAR, Modena June 2008. - - p. 24 - 27.
    biologische landbouw - dierhouderij - rundvee - melkveehouderij - uiers - mastitis - celgetal - organic farming - animal husbandry - cattle - dairy farming - udders - mastitis - somatic cell count
    In order to identify important factors influencing animal health and general disease resistance, detailed qualitative and quantitative farm data were collected from 99 organic dairy farms in the Netherlands. Mastitis incidence and milk quality were focal points of the data collection. In this paper the results of a group of farms which rear dairy calves in suckling systems (n=11) are presented. It was found that compared to other farms in the study (n=88), suckling systems in calf rearing had no clear adverse effects on mastitis incidence and milk quality. In 2006 average clinical mastitis incidence on suckling farms was 14%, on other farms 20%. The percentage of cows with a somatic cell count less than 250,000 at drying-off was lower (60 vs. 66%) at suckling farms. Also immediately after calving the percentage of cows with a somatic cell count less than 250,000 was lower (65 vs. 75%) on suckling farms. Between other farms and suckling farms, but also within suckling farms, distinctively different attitudes to disease management prevailed. Most suckling farms recently introduced suckling systems in calf rearing. Only 1 or 2 generations of suckled heifers had been introduced into the herds up to now. In order to judge whether suckling systems have a potential to improve udder health in future dairy herds, evaluation should be carried out again once suckled heifers constitute the majority of the herd.
    Laag celgetal bij eerste afkalving betaalt zich terug
    Smolders, E.A.A. ; Wagenaar, J.P. - \ 2008
    V-focus 5 (2008)5. - ISSN 1574-1575 - p. 20 - 21.
    melkveehouderij - vaarzen - melkproductie - uiers - diergezondheid - biologische landbouw - celgetal - kalven - dairy farming - heifers - milk production - udders - animal health - organic farming - somatic cell count - calving
    De uiergezondheid van meer dan 7.500 vaarzen van ruim 100 biologische melkveebedrijven zijn beoordeeld op basis van MPR-gegevens (MelkProductieRegistratie 2003-2007). Het celgetal in de eerste MPR na afkalven was gemiddeld 82.000 en was het laagst bij dieren die afkalfden in het begin van de stalperiode. Afkalven op oudere leeftijd had geen gunstige invloed op het celgetal. Vaarzen die afkalfden met een laag celgetal hielden een lager celgetal tijdens de lactatie en werden minder snel afgevoerd
    National Reference Laboratory Milk and Milk Products in the Netherlands Combined Annual Report 2006 and 2007
    Jacobs-Reitsma, W.F. - \ 2008
    Wageningen : RIKILT Wageningen UR (Report / RIKILT, Institute of Food Safety 2008.0009) - 68
    melk - melkproducten - rauwe melk - melk testen - celgetal - alkalisch fosfatase - fosfatasetest - kiemgetal - milk - milk products - raw milk - milk testing - somatic cell count - alkaline phosphatase - phosphatase test - bacterial count
    Betrouwbaar naar gezonde uiers: ontrafelen celgetalgegevens levert uiergezondheidsindex met 85 procent betrouwbaarheid
    Haas, Y. de; Jong, G. de; Lam, T.J.G.M. ; Napel, J. ten; Ouweltjes, W. ; Sampimon, O.C. ; Veerkamp, R.F. ; Windig, J.J. - \ 2008
    Veeteelt 25 (2008)9. - ISSN 0168-7565 - p. 12 - 15.
    melkveehouderij - melkkoeien - uiers - diergezondheid - celgetal - koe-indexen - fokwaarde - dierveredeling - dairy farming - dairy cows - udders - animal health - somatic cell count - cow indexes - breeding value - animal breeding
    Fokken op uiergezondheid kan betrouwbaarder, zo luidt de conclusie van nieuw onderzoek. Door de celgetalgegevens dieper te analyseren ontstaat een index met 85 % betrouwbaarheid, vergelijkbaar met fokwaarden in de zo geroemde Scandinavische landen. Stieren zullen op z'n vroegst in april 2009 een vernieuwde fokwaarde krijgen
    Actieve aanpak celgetal loont : deelnemers studiegroepen UGCN realiseren een significant lager celgetal
    Jansen, J. ; Borne, B.H.P. van den - \ 2008
    Veeteelt 25 (2008)1. - ISSN 0168-7565 - p. 12 - 14.
    melkveehouderij - uiers - melkkwaliteit - celgetal - dierziektepreventie - kennisoverdracht - dairy farming - udders - milk quality - somatic cell count - animal disease prevention - knowledge transfer
    Melkveehouders die gemotiveerd in studiegroepen aan uiergezondheid werken, verbeteren de uiergezondheid van hun veestapel. Dat blijkt uit resultaten van studiegroepen van het Uiergezondheidscentrum Nederland. De dierenarts is hierbij de vertrouwenspersoon en de kennisbron. Maar dierenartsen kunnen nog meer betekenen voor de verbetering van de uiergezondheid
    'Vertrouw op weerstand van de koe' : Gerard Keurentjes gebruikt al vijf jaar geen antibiotica meer bij zijn koeien
    Keurentjes, G. - \ 2007
    Nieuwe oogst / LTO Noord. Editie Oost 3 (2007)6. - ISSN 1871-0891 - p. 16 - 16.
    melkveehouderij - melkvee - diergezondheid - weerstand - ziekteresistentie - celgetal - graskuilvoer - kuilvoer - droge stof - suikergehalte - diervoeding - dairy farming - dairy cattle - animal health - resistance - disease resistance - somatic cell count - grass silage - silage - dry matter - sugar content - animal nutrition
    Gerard Keurentjes houdt zijn koeien gezond met veel aandacht voor de bodem en de weerstand van zijn vee
    Duurmelken bij geiten = Prolonged lactations in goats
    Schuiling, H.J. - \ 2007
    Wageningen : Animal Sciences Group (Rapport / Animal Sciences Group 97) - 17
    geiten - geitenhouderij - melken - melkproductie - productieve levensduur - melkkwaliteit - diergezondheid - schijnzwangerschap - lactatieduur - celgetal - geitenmelk - lactatie - goats - goat keeping - milking - milk production - productive life - milk quality - animal health - pseudopregnancy - lactation duration - somatic cell count - goat milk - lactation
    Het duurmelken van geiten is onderzocht op 6 praktijkbedrijven. Positieve effecten zijn gevonden voor melkproductie, diergezondheid en melkkwaliteit
    Uiergezondheid: Blijf gericht op preventie : Geen excuus om het niet goed te doen
    Smolders, E.A.A. - \ 2006
    Ekoland 26 (2006)4. - ISSN 0926-9142 - p. 16 - 18.
    biologische landbouw - melkveehouderij - mastitis - celgetal - dierziektepreventie - organic farming - dairy farming - somatic cell count - animal disease prevention
    Het celgetal van de melk is een maat voor gezondheid. In biologische melk is het celgetal hoger dan in gangbare melk, wat duidt op meer koeien met een besmetting in de uier. Toch is dat niet nodig. Uit het Bioveemonderzoek komt naar voren dat ook biologische bedrijven prima een laag celgetal kunnen bereiken. Investeer in gezonde koeien, goede hygiene en melktechniek, een goed rantsoen en stressvermijding
    Genotype by Environment Interaction for Milk Production Traits Betweeen Organic and Conventional Dairy Production in The Netherlands
    Nauta, W.J. ; Veerkamp, R.F. ; Brascamp, E.W. ; Bovenhuis, H. - \ 2006
    Journal of Dairy Science 89 (2006)7. - ISSN 0022-0302 - p. 2729 - 2737.
    biologische landbouw - conversie - melkveehouderij - celgetal - melkproductie - genetische parameters - heritability - dierveredeling - organic farming - conversion - dairy farming - somatic cell count - milk production - genetic parameters - heritability - animal breeding - somatic-cell score - genetic-parameters - holstein cows - phenotypic relationships - protein yield - records - models - fat
    Estimates of genetic parameters for organic dairy farming have not been published previously, and neither is information available on the magnitude of genotype by environment interaction (GxE) between organic and conventional farming. However, organic farming is growing worldwide and basic information about genetic parameters is needed for future breeding strategies for organic dairy farming. The goal of this study was to estimate heritabilities of milk production traits under organic farming conditions and to estimate the magnitude of GxE between organic and conventional dairy farming. For this purpose, production records of first-parity Holstein heifers were used. Heritabilities of milk, fat and protein yield, and somatic cell score (SCS) were higher under organic farming conditions. For percentages of fat and protein, heritabilities of organic and conventional production were very similar. Genetic correlations between preorganic and organic, and organic and conventional milk production were 0.79 and 0.80, respectively. For fat yield, these correlations were 0.86 and 0.88, and for protein yield, these were 0.78 and 0.71, respectively. Our findings indicate that moderate GxE was present for yield traits. For percentage of fat and protein and SCS, genetic correlations between organic and conventional and preorganic production were close to unity, indicating that there was no GxE for these traits.
    Converting to organic dairy farming: Consequences for production, somatic cell scores and calving interval of first parity Holstein cows
    Nauta, W.J. ; Baars, T. ; Bovenhuis, H. - \ 2006
    Livestock Science 99 (2006)2-3. - ISSN 1871-1413 - p. 185 - 195.
    conversie - biologische landbouw - melkproductie - tussenkalftijd - leeftijd bij eerste keer kalven - celgetal - conversion - organic farming - milk production - calving interval - age at first calving - somatic cell count - health - herds - milk
    This paper aims to describe the changes prompted by conversion to organic farming for milk production and fertility of first parity Holstein cows. Data was collected for Dutch organic farms, with a distinction made between long-standing-organic farms, converted organic farms and a reference group of conventional farms. The percentage Holstein blood in the herds, milk production (kg milk, % milk fat, % milk protein), somatic cell scores (SCS), calving interval (CI) and age at first calving (AFC) were described over time. An animal model was used to estimate the effects of conversion on different traits based on data from converted organic farms. Milk production was lower and somatic cell counts were higher on long-standing-organic farms than on conventional and converted organic farms. Interestingly, at pre-organic farms, i.e. before their conversion, the milk production level was already lower than at conventional farms. The estimates from our statistical analysis showed a highly significant decrease in milk yield and protein percentage due to conversion. Also fat content decreased, SCS increased and AFC increased significantly. It can be concluded that the conversion to organic farming is a gradual process over years. Dutch farmers who decided during the late 1990s to convert to organic farming, represented a specific group of farmers distinct from conventional farmers, which was reflected by lower milk yields, milk fat percentage and protein percentage before conversion as compared to conventional farms. During conversion, significant changes in milk production, protein and fat contents and somatic cell scores took place. Age of first calving is an important difference between organic and conventional farming
    Celgetal en vet-eiwitverhouding hebben weing verband
    Smolders, E.A.A. - \ 2005
    V-focus 2 (2005)3. - ISSN 1574-1575 - p. 18 - 19.
    melkveehouderij - melkkoeien - energiebehoeften - celgetal - diergezondheid - vet - eiwitgehalte - vetgehalte - dairy farming - dairy cows - energy requirements - somatic cell count - fat - protein content - animal health - fat content
    Exacte cijfers, die aangeven hoe het staat met de energiehuishouding van melkkoeien, zijn er niet. Onderzoek op de Animal Sciences Group moest uitwijzen of het celgetal in relatie tot het vet-eiwitgehalte in de melk een handvat is. Maar de relatie tussen beide getallen blijkt zwak te zijn
    Check title to add to marked list
    << previous | next >>

    Show 20 50 100 records per page

    Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.