Abstract: A package for feed material comprising a package body consisting of sheet plastic and a de-aerating means having a de-aerating area, where an inner sheet layer and an outer sheet layer are provided to form a de-aeration channel to connect an inner de-aeration opening in connection with the interior of the package body with at least one outer de-aeration opening in connection with the environment of the package body. The de-aeration channel comprises two separate chambers interconnected through an overflow opening wherein the inner de-aeration opening is provided at the first chamber and the outer de-aeration opening, at the second chamber so as to increase water tightness.