Fig 1.
Methodological framework of the study.
The productivity model was used to infer the production value (PV), the total metabolizable energy requirement (TME) and the additional costs (AC) of the considered livestock system under alternative scenarios corresponding to status quo and different levels of BRD incidence rate reduction. Input data were obtained from the literature.
Fig 2.
Representation of the French cattle value chain used in the study.
Arrow sizes and percentages indicate the assumed proportion of calves used for the different types of purposes in the beef and the dairy sector and periods at risk of BRD. Arrow ends correspond to the approximate time of departure from the livestock system (slaughter or export). Corresponding ages are indicated on the bottom orange timeline. Source: Groupe Economie du Bétail Institut de l’Elevage. La production de viande bovine en France: qui produit quoi, comment et où? Paris: Institut de l’Elevage. 2011.
Table 1.
Literature references on effects of BRD on cattle farms production performances.
Table 2.
Biological parameters related with BRD and their assumed distribution used in the model.
Study years and locations can be found in S1 Table.
Fig 3.
Box-and-whisker representation of predicted differences in age at maturity of breeding females and young bulls affected and not affected by BRD in the beef and dairy sector.
Fig 4.
Ranges of variation in productivity of the French beef and dairy sectors and their specific compartments in response to BRD eradication in different production stages.
Ranges are represented with box-and-whisker plots. Effects are differentiated according to sector and production stage where BRD is eradicated and level of analysis (sector or compartment).
Table 3.
Predicted changes in productivity of the breeding-fattening, young bull feedlot and veal feedlot compartments in response to BRD incidence reduction in their corresponding at-risk production stages.
In each cell: Mean value (in bold type); between parenthesis: successively, 95% confidence interval with constant market values and 95% confidence interval with 5% variation in market values.
Table 4.
Predicted changes in productivity of the French beef and dairy sectors in response to BRD incidence reduction in specific compartments.
In each cell: Mean value (in bold type); between parenthesis: successively, 95% confidence interval with constant market values and 95% confidence interval with 5% variation in market values.
Table 5.
Results of the sensitivity analysis performed on market prices.
Pearson correlation coefficients between model output (proportion change in sector productivity) and market prices. Only significant values (tested with Pearson correlation test, with 1% significance level) are displayed.