- The Chicken on the other hand, is something else. After a moment, the Fresh Egg can hatch and a Chick will replace it. It'll grow later to a chicken, that isn't really useful. This looks like a kind of way to tell you to not let your inventory packed with recovery items.
There a few things around the egg though : boil it in a hot spring in Mother 3 and it'll turn into a better health item, and chicken can be sold to a profit (even if it's minor against grinding enemies)