If you want to change the default setting of due date on the sow you can either change the period for all sows or you can choose an average due date, based on earlier farrowing (only possible from 2nd parity) 

If you want to change the length of the pregnancy period for all sows you go to “General”, then “Setup”, “Service groups” and then you see this window 




Then you change the number in the box next to “Pregnancy period” to the desired number. To avoid changes in your service groups you must alter e.g., the “Suckling period” so the “Total days” are still the same – here 149 days.  Then click “Ok” and your farrowing dates on the sow cards will change 



If you want the program to calculate an average due data for each sowthen you go to “General”, then “Setup”then “Calculation and then “Other and you will see this window: 




Here you click the small arrow in the “Fixed” box next to “Exp farrow pregnancy period” and change it into “Average”. Your window will then look like this: 




Then click “Ok” and your farrowing dates will be re-calculated and changed on the sow cards