- E. Gruys (1)
- D. Herthnek (1)
- A. Hoek van (1)
- K. Hoogendam (1)
- G.E. Hop (1)
- A. Koets (1)
- J.F. Mee (1)
- F. Mil van (1)
- K. Muller (1)
- M. Nielen (1)
- E. Richardson (1)
- H.J.W. Roermund van (1)
- V. Rutten (1)
- A.G.J. Velthuis (2)
- M.F. Weber (1)
- P.T.J. Willemsen (1)
Assessing Dutch farmers' incentives to join a voluntary Johne's Disease programme
Hop, G.E. ; Velthuis, A.G.J. ; Frankena, K. - \ 2011
NJAS Wageningen Journal of Life Sciences 58 (2011)1-2. - ISSN 1573-5214 - p. 57 - 64.
dairy herds - mycobacterium-paratuberculosis - quality-assurance - risk-factors - management - knowledge - behaviors - infection - economics - attitudes
The incentives of Dutch dairy farmers to participate in a voluntary Johne's Disease (JD) control programme were investigated using a case–control design. Furthermore, farm and farmers’ characteristics of case and control farmers were compared. Dairy farmers in the northern part of the Netherlands were interviewed based on a standardized questionnaire. Exact logistic regression analysis showed that participating farmers (case farmers) were more motivated by internal factors (that relate to farm performance and the individual farmer) than non-participating farmers (control farmers). For example, animal health and welfare awareness had an increased odds of 33.3, and economic losses due to JD of 4.5. External factors relating to the performance of the dairy sector as well as to consumer health, had little influence on the decision to participate. Case farmers were less interested in test costs than control farmers. Furthermore, the case farmers liked to have a well-organized farm now and in the future and tried to avoid (potential) economic losses due to JD as much as possible. They were more focused on future gains than on current costs. In contrast, the control farmers were motivated merely by the direct and future costs that related to the JD programme, including costs for changing management. The effect of currently being a control farmer, compared with case farmers, showed increased odds of almost 4 and 64-fold, respectively, on ‘change in test costs’ and ‘change in regulatory requirements’ as incentives to participate in the future
Paratuberculosis sero-status and milk production, SCC and calving interval in Irish dairy herds
Hoogendam, K. ; Richardson, E. ; Mee, J.F. - \ 2009
Irish Veterinary Journal 62 (2009)4. - ISSN 0368-0762 - p. 265 - 271.
bovine viral diarrhea - mycobacterium-paratuberculosis - johnes-disease - infection - cattle - cows - usa - association - parameters - michigan
The objective of this study was to investigate the impact of paratuberculosis sero-status on milk yield, fat, protein, somatic cell count and calving interval in Irish dairy herds. Serum from all animals over 12 months of age (n=2,602) in 34 dairy herds was tested for antibodies to Mycobacterium avium subsp. paratuberculosis using an ELISA. Herds were categorised by sero-status into positive, non-negative and negative, where a positive herd contained two or more positive cows, a non¿negative herd contained only one positive cow and a negative herd contained no positive cows. Data at animal, parity and herd-level were analysed by multiple regression using general linear models. Positive herds (mean herd size=129 cows) and non-negative herds (81 cows) were larger than negative herds (72 cows) (P
Milk quality assurance for paratuberculosis: simulation of within-herd infection dynamics and economicsof within-herd infection dynamics and economics
Weber, M.F. ; Nielen, M. ; Velthuis, A.G.J. ; Roermund, H.J.W. van - \ 2008
Veterinary Research 39 (2008)12. - ISSN 0928-4249 - p. 1 - 20.
avium subsp paratuberculosis - pasteurized cows milk - bovine johnes-disease - mycobacterium-paratuberculosis - monitoring program - heat inactivation - fecal samples - bulk raw - cattle - temperatures
bulk milk quality assurance programme for Mycobacterium avium subsp. paratuberculosis (Map) in dairy herds was simulated with a stochastic simulation model (JohneSSim). The aim of this study was to evaluate the epidemiological and economic effects of preventive management measures and various test schemes in a simulated population of closed Dutch dairy herds over a 20-year period. Herds were certified as `low-Map bulk milk' if, with a certain probability, the concentration of Map in bulk milk did not exceed a maximum acceptable concentration of 103 Map organisms per litre (based on pasteurisation studies). The programme started with an initial assessment; test-negative herds entered a surveillance procedure and test-positive herds a control procedure. The simulations showed that herd examinations by ELISA for the initial assessment, surveillance and control procedures effectively ensure the quality of `low-Map bulk milk': > 75% of simulated herds were certified and > 96% of certified herds produced bulk milk with <103 Map/L if the initial herd-level prevalence was 30%. Preventive management measures only had a minor effect on bulk milk quality of certified herds. Culling based on biennial faecal culture was more effective than culling based on annual ELISA. Average total discounted costs for 20-year participation in a programme consisting of initial assessment by ELISA, surveillance by biennial ELISA and control by biennial faecal culture were per herd. In conclusion, this study shows that a bulk milk quality assurance programme for closed Dutch dairy herds is feasible and provides information on the cost-effectiveness of different programmes. The concepts of this study equally apply to other countries because mechanisms of paratuberculosis infection, disease, and testing are comparable in other dairy cattle populations.
Sensitive detection of Myobacterium avium subsp paratuberculosis in bovine semen by real-time PCR
Herthnek, D. ; Englund, S. ; Willemsen, P.T.J. ; Bolske, G. - \ 2006
Journal of Applied Microbiology 100 (2006)5. - ISSN 1364-5072 - p. 1095 - 1102.
polymerase-chain-reaction - mycobacterium-paratuberculosis - crohns-disease - johnes-disease - diagnosis - organs - is900 - milk - dna - herpesvirus
Aims: To develop a fast and sensitive protocol for detection of Mycobacterium avium subsp. paratuberculosis (MAP) in bovine semen and to make a critical evaluation of the analytical sensitivity. Methods and Results: Processed semen was spiked with known amounts of MAP. Semen from different bulls as well as semen of different dilutions was tested. The samples were treated with lysing agents and beadbeating and the DNA was extracted with phenol and chloroform. Real-time PCR with a fluorescent probe targeting the insertion element IS900 detected as few as 10 organisms per sample of 100 ¿l semen. PCR-inhibition was monitored by inclusion of an internal control. Pre-treatment with immunomagnetic separation was also evaluated, but was not shown to improve the overall sensitivity. Conclusions: Real-time PCR is a sensitive method for detection of MAP in bovine semen. Lysis by mechanical disruption followed by phenol and chloroform extraction efficiently isolated DNA and removed PCR-inhibitors. Significance and Impact of the Study: The high sensitivity of the applied method allows reliable testing of bovine semen used for artificial insemination to prevent the spread of Johne's disease, caused by MAP.
Progressive bovine paratuberculosis is associated with local loss of CD4(+) T cells, increased frequency of gamma delta T cells, and related changes in T-cell function
Koets, A. ; Rutten, V. ; Hoek, A. van; Mil, F. van; Muller, K. ; Bakker, D. ; Gruys, E. ; Eden, W. van - \ 2002
Infection and Immunity 70 (2002)7. - ISSN 0019-9567 - p. 3856 - 3864.
blood mononuclear-cells - lymphoblast proliferative capacity - johnes-disease - monoclonal-antibodies - mycobacterium-paratuberculosis - para-tuberculosis - lymphocytes-t - ovine paratuberculosis - lymph-node - alpha-beta
Bovine paratuberculosis is caused by the infection of young calves with Mycobacterium avium subsp. paratuberculosis, resulting in a chronic granulomatous infection of predominantly the ileum. After an incubation period of 2 to 5 years, the disease becomes progressive in some of the chronically infected, but asymptomatic cows. This results in a protein-losing enteropathy that will ultimately be fatal. A loss of cell-mediated immune responses in symptomatic animals has been described, but no information is available concerning immune reactivity in the intestine. We sought to investigate putative disease status-associated lymphocyte subset distributions and antigen-specific functional characteristics of mononuclear cells isolated from blood, gut-associated lymphoid tissue, and the intestinal walls of 22 cows in different stages of disease and in control animals. The results demonstrated a significant decrease in CD4+ T-cell frequency and a significant increase in TcR1-N12+ T-cell frequency in ileum lamina propria lymphocytes of symptomatic animals compared to the asymptomatic shedders. Immunohistology revealed that there was also an absolute decrease in the number of CD4+ T cells in sections of the lesional ileum. Our findings also indicated that both peripheral and intestinal cell-mediated responses are decreased in symptomatic animals compared to asymptomatic animals. We conclude that the decrease in cell-mediated responses is likely related to a loss of antigen-specific CD4+ T cells, which is most prominent in the lesional ileum from symptomatic animals, thus contributing to the progressive nature of bovine paratuberculosis