This manual describes the use of the transfer model to estimate the concentration of dioxins (total TEQ) in milk of the dairy cow. This model has several input fields (left side) and output fields (right side). The input and results can be saved using the button “Report (*.docx)”. Source information and a citation suggestion are provided (top).
Step1: Contamination level of feed
The user can provide the contamination level (expressed in ng total TEQ/kg feed) in the contamination field.
Step 2: Feed intake
The user has to select the type of feed that was contaminated with dioxins. For this, the user chooses first between a summer or winter feed regimen and then the relevant type of feed.
a) This can either be:
- Total feed intake
- Grass silage
- Maize silage
- Total compound feed (blend of various raw materials and additives)
- Compound feed ingredients
When compound feed ingredients are selected, the user has to select the contaminated compound feed ingredient from a drop down menu
b) After selecting the contaminated feed (ingredient), a default feed intake value is provided (in kg dry matter per day)1. The user can adjust this default value to the value corresponding to the actual feeding regime. The user should be aware that whether the feed of the dairy cow is protein rich or protein poor can influence the default feed ingredient intake. The default values for compound feed ingredients used here are based on a protein-rich diet
Step 3: Milk production
To estimate the concentration of dioxins in milk, a default value for milk production is provided (expressed in L/day)1. The user can adjust this default value to the value corresponding to the actual milk production.
Step 4: Exposure period of dairy cow to contaminated feed
To estimate the concentration of dioxins in milk, the user has to enter the duration of exposure of the animals to the contaminated feed (ingredient) (expressed in days).
Step 5: Regulatory limit (optional)
Regulatory limits (for instance maximum levels) (expressed in pg TEQ/g milk fat or body fat) can be inserted. These limits will be displayed in the output graphs on the screen, but not yet in the report.
Step 6: Results
A graph with the total TEQ concentration versus time will be generated for milk (expressed in pg TEQ/g milk fat) and body fat (expressed in pg TEQ/g body fat).
Step 7: Saving input and output
Using a “Report (*.docx)” button present in the left corner, input data and the results of the model run can be stored locally as a report file in word. The optional regulatory limits are not yet visible in the report. Input data and results are not stored at the website.
Step 8: Citation suggestion
At the top of the model page the references that describe the model are listed, as well as a citation suggestion. Please use the suggested citation at the bottom of the webpage, when referring to the model.
1 Van Raamsdonk LWD, Kan CA, Meijer GAL, Kemme PA (2007) Key figures for some farm animals and their consumption patterns [in Dutch]; https://research.wur.nl/en/publications/kengetallen-van-enkele-landbouwhuisdieren-en-hun-consumptiepatron.