strongly related to the use of plant control package 3. It is therefore considered reasonable to assume
that plant managers are honest in applying the incentive system parameters they choose when plant
threshold levels are low.
The need to simplify the analysis has resulted in at least three important limitations. First,
although this analysis gives useful insights in the trade-offs between prevalence reduction and related
costs and gains, it must be emphasized that for determining the appropriate bacteriological threshold
level also public health aspects have to be considered.
Second, in evaluating incentives for Salmonella control, the food safety externalities caused by
joint production of quality attributes are often overlooked but may alter the willingness of a firm to
adopt food safety controls (Roberts, 2005).
Finally, plants using logistic slaughter are considered to test all herds for Salmonella and
slaughter positively tested herds at the end of the day instead of at another location. Logistic slaughter
only reduces the prevalence of Salmonella effectively when the delay between sampling pig herds at
the farm and delivery to the slaughterhouse is at a minimum. In the future, the analysis could be
extended to determine how the geographic distribution of plant capacity affects the choice between
slaughtering positively tested herds at the end of the day instead or at another location. And with the
development of faster testing technologies one might expect that production history performance
information also contributes to the cost effectiveness of logistic slaughter.
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