|Bayesian estimation of the Hepatitis E virus seroprevalence in the Netherlands in populations with different degree of exposure to swine.
Bouwknegt, M. ; Engel, B. ; Herremans, M.M.P.T. ; Widdowson, M.A. ; Worm, H.C. ; Koopmans, M.P.G. ; Frankena, K. ; Roda Husman, A.M. de; Jong, M.C.M. de; Poel, W.H.M. van der - \ 2007
|Bayesian estimation of the hepatitis E virus seroprevalence in The Netherlands in populations with different degrees of exposure to swine
Bouwknegt, M. ; Engel, B. ; Herremans, M.M.P.T. ; Widdowson, M.A. ; Worm, H.C. ; Koopmans, M.P.G. ; Frankena, K. ; Roda Husman, A.M. De; Jong, M.C.M. de; Poel, W.H.M. van der - \ 2006
|De mogelijke rol van het 'bacteriemengsel' Cobio Lisier in het stikstofbeheer van melkveehouderijbedrijven. Een speculatieve verhandeling ten behoeve van het 'Cobio Lisier project' van de provincie Gelderland
Boer, J.A. de; Bouwknegt, K. ; Janssen, B. ; Keulen, H. van - \ 2005
In: Eindrapportage 'De rol van Cobio Lisier in het optimaliseren van het stikstofmanagement op rundveehouderijbedrijven'. Een project in Milieuzorggebeid Neede-Borculo DLV Rundvee Advies - p. 30 - 34.
Prevalence estimation and risk factors for Escherichia coli O157 on Dutch dairy farms
Schouten, J.M. ; Bouwknegt, M. ; Giessen, A.W. van de; Frankena, K. ; Jong, M.C.M. de; Graat, E.A.M. - \ 2004
Preventive Veterinary Medicine 64 (2004)1. - ISSN 0167-5877 - p. 49 - 61.
shiga-toxin - manure slurry - survival - cattle - herd - transmission - netherlands - infection
To estimate the prevalence of Escherichia coli O157 on Dutch dairy herds, faecal samples were collected once from 678 randomly selected dairy farms in the period October 1996–December 2000. Samples were cultured for E. coli O157. Thirty-eight isolates were tested for virulence genes (eae, VT1 and VT2). A questionnaire about farm characteristics was taken from the farm manager, resulting in variables that could be analysed to identify and quantify factors associated with presence of E. coli O157. In total, 49 of the 678 herds (7.2%) showed at least one positive pooled sample. E. coli O157 was not isolated from herds sampled in December–April in consecutive years (except for one isolate found in March, 2000). VT- and eae-genes were found in 37 and 38 isolates, respectively. Logistic regression was performed on variables obtained from the questionnaire, comparing E. coli O157-positive herds to negative herds. To account for season, a sine function was included in the logistic regression as an offset variable. In the final model, the presence of at least one pig at the farm (OR=3.4), purchase of animals within the last 2 years before sampling (OR=1.9), supply of maize (OR=0.29) to the cows, and sampling a herd in the year 1999 or 2000 (compared to sampling in 1998; OR=2.1 and 2.9, respectively) had associations with the presence of E. coli O157.
|'De rol van Cobio Lisier in het optimaliseren van het stikstofmanagement op rundveehouderijbedrijven'
Boer, J.A. de; Bouwknegt, K. ; Janssen, B. ; Keulen, H. van - \ 2004
Deventer : DLV Rundvee Advies bv - 6 p.
|Surveillance of zoonotic bacteria in fattening pigs in The Netherlands
Giessen, A.W. van de; Bouwknegt, M. ; Dam-Deisz, W.D.C. ; Wannet, W.J.B. ; Nieuwenhuis, M. ; Graat, E.A.M. ; Visser, G. - \ 2003
|Surveillance of STEC O157 in farm animals
Giessen, A.W. van de; Schouten, J.M. ; Bouwknegt, M. ; Dam-Deisz, W.D.C. ; Graat, E.A.M. ; Frankena, K. ; Jong, M.C.M. de; Visser, G. - \ 2003
|Monitoring STEC O157 in dairy cows and veal calves: Prevalences, trends and risk factors
Bouwknegt, M. ; Schouten, J.M. ; Giessen, A.W. van de; Frankena, K. ; Jong, M.C.M. de; Graat, E.A.M. - \ 2003
Surveillance of zoonotic bacteria in farm animals in The Netherlands. Results from January 1998 until December 2000
Bouwknegt, M. ; Dam-Deisz, W.D.C. ; Schouten, J.M. ; Wannet, W.J.B. ; Pelt, W. van; Visser, G. ; Giessen, A.W. van de - \ 2003
Bilthoven : RIVM (RIVM rapport 285859013/2003) - 65
huisdieren - zoönosen - volksgezondheid - campylobacter - salmonella - escherichia coli - toezicht - nederland - domestic animals - zoonoses - public health - campylobacter - salmonella - escherichia coli - surveillance - netherlands
To obtain reliable quantitative data on the occurrence of zoonotic bacteria in farm animals in The Netherlands, a surveillance programme was implemented in April 1997. Results for January 1998 through December 2000 are presented in this report. In this period, faecal samples from in total 2,378 flocks/herds of layers, broilers, finishing pigs, dairy cattle and veal calves were examined for the presence of Salmonella spp., Campylobacter spp. and/or verocytotoxin-producing E. coli O157. Questionnaires were used to obtain data for risk factor analyses. For layers, prevalences of salmonella positive flocks were 12% (1998, using Rappaport-Vassiliadis (RV) as selective enrichment medium) and averaged around 20% in 1999 and 2000 (using both RV and modified semisolid RV (MSRV)); for broilers, the salmonella prevalence declined from 28% (1998, RV) to 16% (2000, RV & MSRV). For finishing pig, 34% (1998; 4th quarter only), 13% (1999) and 16% (2000) positive herds were identified, while for dairy cattle and veal calves, salmonella prevalences were around 3% (based on the use of RV only). Serotype discrimination showed the predominance of S. Enteritidis (mainly phagetype PT4) in layers in all years; for broilers this serotype prevailed until 1999, whereas S. Paratyphi B var. Java prevailed in 2000. In finishing pigs, S. Typhimurium predominated, with an increase of phagetype DT104 during the study period. The campylobacter prevalence in broilers decreased from 31% (1998) to 18% (1999), reaching 24% in 2000. Finishing pigs, dairy cattle and veal calves showed lower campylobacter prevalences for 1999 compared to 1998. C. jejuni was the dominating species in broilers and dairy cattle, whereas C. coli predominated in pigs; both species prevailed equally in veal calves. Prevalence estimates for E. coli O157 in dairy cattle were 5% (1998), 8% (1999) and 6% (2000; 8% with an adjusted processing of samples); for veal calves these were 5% (1998), 9% (1999) and 11% (2000; 17% with the adjusted method). PCR-test results revealed the presence of the virulence associated SLT- and/or eae-genes in all isolates examined. Potential risk factors were identified for E. coli O157 in dairy cattle and for Campylobacter spp. in broilers
|Risk factor analysis of Escherichia coli O157 on Dutch dairy farms
Schouten, J.M. ; Bouwknegt, M. ; Giessen, A.W. van de; Frankena, K. ; Graat, E.A.M. - \ 2001
In: Proceedings of Society for Veterinary Epidemiology and Preventive Medicine : Noordwijkerhout, 2001 / Menzies, F.D., Reid, S.W.J., - p. 202 - 210.
|Iodide uptake in the maternal, fetal and neonatal rat : influence of mild (MID) and moderately severe iodine deficiency(MID+P)
Schröder-van, J.P. der; Bouwknegt, M. ; Kastelijn, J. ; Heide, D. van der - \ 1999
In: Proceedings of the 26th Annual Meeting of the European Thyroid Association,Milan,Italy, 28 August-1 September 1999 / ed. by G. Faglia. - Milan : Editrice Kurtis, 1999. - (Journal of endocrinological investigation; 22 (1999) Suppl. to No. 6) - p. 36 - 36.