A modeling study on the sustainability 
of a certification-and-monitoring program 
for paratuberculosis in cattle

Ezanno, Pauline; Schaik, G. van; Weber, M.F.; Heesterbeek, J.A.P.

doi:10.1051/vetres:2005032

Cited by 10 publications

(8 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This model couples within-farm dynamics through observed between-farm animal trade movements. Compared to the few published models of Map spread at a regional scale [ 32 , 33 ], this model is original as it simultaneously accounts for stochastic demographic and infection dynamics within dairy farms, indirect local transmission, and data on animal trade, herd size, and farm management. This level of detail is required to accurately represent Map spread.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Modelling of paratuberculosis spread between dairy cattle farms at a regional scale

Beaunée

Vergu

Ezanno

2015

Vet Res

Self Cite

View full text Add to dashboard Cite

Mycobacterium avium subsp. paratuberculosis (Map) causes Johne’s disease, with large economic consequences for dairy cattle producers worldwide. Map spread between farms is mainly due to animal movements. Locally, herd size and management are expected to influence infection dynamics. To provide a better understanding of Map spread between dairy cattle farms at a regional scale, we describe the first spatio-temporal model accounting simultaneously for population and infection dynamics and indirect local transmission within dairy farms, and between-farm transmission through animal trade. This model is applied to Brittany, a French region characterized by a high density of dairy cattle, based on data on animal trade, herd size and farm management (birth, death, renewal, and culling) from 2005 to 2013 for 12 857 dairy farms. In all simulated scenarios, Map infection highly persisted at the metapopulation scale. The characteristics of initially infected farms strongly impacted the regional Map spread. Network-related features of incident farms influenced their ability to contaminate disease-free farms. At the herd level, we highlighted a balanced effect of the number of animals purchased: when large, it led to a high probability of farm infection but to a low persistence. This effect was reduced when prevalence in initially infected farms increased. Implications of our findings in the current enzootic situation are that the risk of infection quickly becomes high for farms buying more than three animals per year. Even in regions with a low proportion of infected farms, Map spread will not fade out spontaneously without the use of effective control strategies.Electronic supplementary materialThe online version of this article (doi:10.1186/s13567-015-0247-3) contains supplementary material, which is available to authorized users.

show abstract

Section: Discussionmentioning

confidence: 99%

“…[ 31 ] Moreover, the large influence of the farm management on Map spread has been evidenced [ 30 ]. At a regional scale, fewer approaches have been proposed for paratuberculosis [ 32 , 33 ], none accounting for the within-farm indirect Map transmission in relation with farm management.…”

Section: Introductionmentioning

confidence: 99%

Modelling of paratuberculosis spread between dairy cattle farms at a regional scale

Beaunée

Vergu

Ezanno

2015

Vet Res

Self Cite

View full text Add to dashboard Cite

show abstract

“…The new programme is run in addition to the pre-existing certification-and-surveillance programme for 'Map-free' herds [4,8,37]. In the new programme, farmers may choose freely between test schemes C and D (Tab.…”

Section: Discussionmentioning

confidence: 99%

Milk quality assurance for paratuberculosis: simulation of within-herd infection dynamics and economics

Weber

Nielen²,

Velthuis³

et al. 2008

Vet. Res.

Self Cite

View full text Add to dashboard Cite

-A 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 10 3 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 'lowMap bulk milk': > 75% of simulated herds were certified and > 96% of certified herds produced bulk milk with < 10 3 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 e16 × 10 3 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. dairy cattle / milk / paratuberculosis / stochastic simulation model / quality assurance programme

show abstract

“…Such a situation will be typical for herds with very low yearly purchase rates (e.g. dairy herds in Brittany without any fattening activity; [10]) or in the context of certification, when only certified animals are purchased (with a very low risk of being infected; [11]). In Europe, control of Map introduction into cattle herds has indeed priority over control of within-herd Map spread.…”

Section: Introductionmentioning

confidence: 99%

Predicting fadeout versus persistence of paratuberculosis in a dairy cattle herd for management and control purposes: a modelling study

Marcé

Ezanno

Seegers

et al. 2011

Vet Res

Self Cite

View full text Add to dashboard Cite

Epidemiological models enable to better understand the dynamics of infectious diseases and to assess ex-ante control strategies. For Mycobacterium avium subsp. paratuberculosis (Map), possible transmission routes have been described, but Map spread in a herd and the relative importance of the routes are currently insufficiently understood to prioritize control measures. We aim to predict early after Map introduction in a dairy cattle herd whether infection is likely to fade out or persist, when no control measures are implemented, using a modelling approach. Both vertical transmission and horizontal transmission via the ingestion of colostrum, milk, or faeces present in the contaminated environment were modelled. Calf-to-calf indirect transmission was possible. Six health states were represented: susceptible, transiently infectious, latently infected, subclinically infected, clinically affected, and resistant. The model was partially validated by comparing the simulated prevalence with field data. Housing facilities and contacts between animals were specifically considered for calves and heifers. After the introduction of one infected animal in a naive herd, fadeout occurred in 66% of the runs. When Map persisted, the prevalence of infected animals increased to 88% in 25 years. The two main transmission routes were via the farm's environment and in utero transmission. Calf-to-calf transmission was minor. Fadeout versus Map persistence could be differentiated with the number of clinically affected animals, which was rarely above one when fadeout occurred. Therefore, early detection of affected animals is crucial in preventing Map persistence in dairy herds.

show abstract

A modeling study on the sustainability of a certification-and-monitoring program for paratuberculosis in cattle

Cited by 10 publications

References 15 publications

Modelling of paratuberculosis spread between dairy cattle farms at a regional scale

Modelling of paratuberculosis spread between dairy cattle farms at a regional scale

Milk quality assurance for paratuberculosis: simulation of within-herd infection dynamics and economics

Predicting fadeout versus persistence of paratuberculosis in a dairy cattle herd for management and control purposes: a modelling study

Contact Info

Product

Resources

About