Hello Giorgio,

Yes. You can make the built-in "publish from" field mandatory for a certain document type; please follow the steps below:

1) Go to Site Manager -> Development -> Document types and edit your document type
2) On General tab uncheck Use publish from/publish to: (set to false), save and switch to Fields tab
3) use the gear icon to add a system attribute
4) Use Document attributes and from the second drop down list select desired attribute - DocumentPublishTo
5) Uncheck "Allow emtpy value"
6) Set other settings like Field type - set it to calendar, field caption, etc.
7) Save it.

You may need to do the same for DocumentPublishFrom field.

Best Regards,
Edward Hillard