If you print the actionlist and use it in the stable to note for example treatments at farrowing, then it is possible to remove til zeros from the action list. 



Click on the green symbol "Layout setup" or right-click on the title columns. Then click on the tab "Printout":



Then find the column where you do not want the zeros and in the dropdown menu you choose "Blank":



Then the zeros will not be shown on the printed actionlist.