M.A.P.M. van Asseldonk

Awareness and perceived value of economic information in controlling somatic cell count.

A survey of dairy farmers assessed whether they were aware of the potential production and economic benefits of adopting and implementing efficient practices to control somatic cell count (SCC), and whether providing them with additional information on projected economic losses on a regular basis might motivate them to implement enhanced control programmes. In-depth interviews revealed that the majority of the dairy farmers perceived cow-specific and herd-specific projected losses due to elevated SCCs, as not very relevant to them. Farmers considered that SCC was already monitored regularly at individual cow level, which provided them with adequate information to support decision-making. The farmers justified their actions with regard to SCC control in terms of their intention to manage the problem, and their belief in whether their efforts would be successful. Actions were rationalised in a specific context comprising the intertwined notions of intentions and efficacy beliefs.

Multi Criteria Decision Making to evaluate control strategies of contagious animal diseases

The decision on which strategy to use in the control of contagious animal diseases involves complex trade-offs between multiple objectives. This paper describes a Multi Criteria Decision Making (MCDM) application to illustrate its potential support to policy makers in choosing the control strategy that best meets all of the conflicting interests. The presented application focused on the evaluation of alternative strategies to control Classical Swine Fever (CSF) epidemics within the European Union (EU) according to the preferences of the European Chief Veterinary Officers (CVO). The performed analysis was centred on the three high-level objectives of epidemiology, economics and social ethics. The appraised control alternatives consisted of the EU compulsory control strategy, a pre-emptive slaughter strategy, a protective vaccination strategy and a suppressive vaccination strategy. Using averaged preference weights of the elicited CVOs, the preference ranking of the control alternatives was determined for six EU regions. The obtained results emphasized the need for EU region-specific control. Individual CVOs differed in their views on the relative importance of the various (sub)criteria by which the performance of the alternatives were judged. Nevertheless, the individual rankings of the control alternatives within a region appeared surprisingly similar. Based on the results of the described application it was concluded that the structuring feature of the MCDM technique provides a suitable tool in assisting the complex decision making process of controlling contagious animal diseases.

Economic assessment of Q fever in the Netherlands.

In this paper the economic impact of controlling the Q fever epidemic in 2007-2011 in the Netherlands is assessed. Whereas most of the long-term benefits of the implemented control programme stem from reduced disease burden and human health costs, the majority of short-term intervention costs were incurred in the dairy goat sector. The total intervention cost in agriculture amounted approximately 35,000 Euro per DALY occurred. By culling of infected animals, breeding prohibition and vaccination, the epidemic seems to be under control. As the dairy goat vaccination programme continues, future expenses in maintaining the current protected status are relatively low.

Insurance against weather risk: Use of heating degree-days from non-local stations for weather derivatives

Summary¶Weather derivatives enable policy-holders to safeguard themselves against extreme weather conditions. The effectiveness and the efficiency of the risk transfer is determined by the spatial risk basis, which is the stochastic dependency of the local weather outcome being insured and the outcome of the weather underlying the insurance instrument. The lower this risk basis the higher the effectiveness and the efficiency of the risk transfer. To study the spatial risk basis component in relation to the design and evaluation of a weather derivative contract to insure for heating degree-days (HDD), the historical temperature records were analyzed for five sites across the Netherlands.Sensitivity and specificity of the insurance instrument were used to quantify the potential spatial risk basis. Setting indemnification beyond a half standard deviation above the mean meant that between 60% and 76% of the indemnable HDD were classified correctly, while 82% to 99% of the non-indemnable HDD were classified correctly. These results indicate that the spatial risk basis is a major concern and that successful weather derivatives require the utilization of carefully selected weather data obtained from meteorological stations in close proximity to the area being insured.

Comparing risk in conventional and organic dairy farming in the Netherlands: an empirical analysis.

This study was undertaken to contribute to the understanding of why most dairy farmers do not convert to organic farming. Therefore, the objective of this research was to assess and compare risks for conventional and organic farming in the Netherlands with respect to gross margin and the underlying price and production variables. To investigate the risk factors a farm accountancy database was used containing panel data from both conventional and organic representative Dutch dairy farms (2001-2007). Variables with regard to price and production risk were identified using a gross margin analysis scheme. Price risk variables were milk price and concentrate price. The main production risk variables were milk yield per cow, roughage yield per hectare, and veterinary costs per cow. To assess risk, an error component implicit detrending method was applied and the resulting detrended standard deviations were compared between conventional and organic farms. Results indicate that the risk included in the gross margin per cow is significantly higher in organic farming. This is caused by both higher price and production risks. Price risks are significantly higher in organic farming for both milk price and concentrate price. With regard to production risk, only milk yield per cow poses a significantly higher risk in organic farming.

Process audits versus product quality monitoring of bulk milk

Assessment of milk quality is based on bulk milk testing and farm certification on process quality audits. It is unknown to what extent dairy farm audits improve milk quality. A statistical analysis was conducted to quantify possible associations between bulk milk testing and dairy farm audits. The analysis comprised 64.373 audit outcomes on 26,953 dairy farms, which were merged with all conducted laboratory tests of bulk milk samples 12 mo before the audit. Each farm audit record included 271 binary checklist items and 52 attention point variables (given to farmers if serious deviations were observed), both indicating possible deviations from the desired farm situation. Test results included somatic cell count (SCC), total bacterial count (TBC), antimicrobial drug residues (ADR), level of butyric acid spores (BAB), freezing point depression (FPD), level of free fatty acid (FFA), and milk sediment (SED). Results show that numerous audit variables were related to bulk milk test results, although the goodness of fit of the models was generally low. Cow hygiene, clean cubicles, hygiene of milking parlor, and utility room were positively correlated with superior product quality, mainly with respect to SCC, TBC, BAB, FPD, FFA, and SED. Animal health or veterinary drugs management (i.e., drug treatment recording, marking of treated animals, and storage of veterinary drugs) related to SCC, FPD, FFA, and SED. The availability of drinking water was related to TBC, BAB, FFA, and SED, whereas maintenance of the milking equipment was related mainly to SCC, FPD, and FFA. In summary, bulk milk quality and farm audit outcomes are, to some degree, associated: if dairy farms are assessed negatively on specific audit aspects, the bulk milk quality is more likely to be inferior. However, the proportion of the total variance in milk test results explained by audits ranged between 4 and 13% (depending on the specific bulk milk test), showing that auditing dairy farms provides additional information but has a limited association with the outcome of a product quality control program. This study suggests that farm audits could be streamlined to include only relevant checklist items and that bulk milk quality monitoring could be used as a basis of selecting farms for more or less frequent audits.

Stochastic Simulation of Catastrophic Hail and Windstorm Indemnities in the Dutch Greenhouse Sector

A risk analysis was performed to examine the effect of changes in the Dutch greenhouse sector on the probability of occurrence and magnitude of indemnities induced by catastrophic natural hazards. Analyzed historical indemnities, which included direct and consequential losses resulting from severe hail and windstorms, were used as input in a stochastic simulation model. Applications of the stochastic simulation model were illustrated under alternative risk conditions. A comparison was made between the current structure of greenhouse production and the expected structure in the next decade that differs with respect to the spatial distribution and average size.

Risk-based audit selection of dairy farms.

Dairy farms are audited in the Netherlands on numerous process standards. Each farm is audited once every 2 years. Increasing demands for cost-effectiveness in farm audits can be met by introducing risk-based principles. This implies targeting subpopulations with a higher risk of poor process standards. To select farms for an audit that present higher risks, a statistical analysis was conducted to test the relationship between the outcome of farm audits and bulk milk laboratory results before the audit. The analysis comprised 28,358 farm audits and all conducted laboratory tests of bulk milk samples 12 mo before the audit. The overall outcome of each farm audit was classified as approved or rejected. Laboratory results included somatic cell count (SCC), total bacterial count (TBC), antimicrobial drug residues (ADR), level of butyric acid spores (BAB), freezing point depression (FPD), level of free fatty acids (FFA), and cleanliness of the milk (CLN). The bulk milk laboratory results were significantly related to audit outcomes. Rejected audits are likely to occur on dairy farms with higher mean levels of SCC, TBC, ADR, and BAB. Moreover, in a multivariable model, maxima for TBC, SCC, and FPD as well as standard deviations for TBC and FPD are risk factors for negative audit outcomes. The efficiency curve of a risk-based selection approach, on the basis of the derived regression results, dominated the current random selection approach. To capture 25, 50, or 75% of the population with poor process standards (i.e., audit outcome of rejected), respectively, only 8, 20, or 47% of the population had to be sampled based on a risk-based selection approach. Milk quality information can thus be used to preselect high-risk farms to be audited more frequently.

Break-even analysis of costs for controlling Toxoplasma gondii infections in slaughter pigs via a serological surveillance program in the Netherlands

Toxoplasma gondii (T. gondii) is a food safety hazard which causes a substantial human disease burden and cost-of-illness. Infected pig meat is a common source of toxoplasmosis. A break-even analysis was conducted to estimate the point for which the intervention cost at fattening pig farms equaled the cost of averted human disease burden and cost-of-illness minus the costs of a T. gondii surveillance program. The surveillance program comprised serological testing of blood samples taken at slaughter. Break-even points were determined given alternative levels of the effectiveness of the intervention program (10% up to 90% in steps of 10%), the value of an averted DALY (20,000, 50,000 and 80,000 Euro), and threshold of sample prevalence for a farm to be under intervention (5% up to 50% out of 20 samples in steps of 5%). Since test characteristics are a determining factor in the break-even analysis, and literature is inconclusive concerning sensitivity (se) and specificity (sp) of the serological test kit used, two alternative sets of assumptions were analysed. The estimated maximum costs of an intervention if only benefits for domestic consumers were accounted amounted approximately 2981 Euro (se=98.9% and sp=92.7%) versus 4389 Euro (se=65.2% and sp=97.4%) per year per fattening pig farm under intervention assuming an effectiveness of 50%, 50,000 Euro per averted DALY and threshold T. gondii sample prevalence of 5% for a farm to be under intervention. Since almost 80% of the gross domestic production is exported corresponding break-even values increased up to 12,034 Euro and 18,366 Euro if benefits for consumers abroad were included as well. Empirical research to strengthen the knowledge about the efficacy of a farm intervention measures is recommended.

Modelling of Catastrophic Farm Risks Using Sparse Data

This paper compares alternative ways of conducting a farm risk analysis using sparse data with a special reference to catastrophe events. For this purpose kernel and multivariate normal smoothing procedures are proposed and applied to generate (simulate) the joint distributions of crop yields and prices. The analysis showed that the functional forms chosen to generate the joint distribution substantially impacted the density in the tail of the distribution, although they were parameterised with the same data. The differences in the optimal farm plan (i.e. activity levels) resulting from the optimisation of net farm income, obtained from a utility-efficient programming model, were less profound.