Yes, I am afraid that's a problem that's common with Ape 2.5. (grrr cat... biting ... my feet) I am afraid, if you need the original text, that you would have to copy and paste it somewhere save. Then re-open your project and paste it back in. If you save it again, then it will remain.
Beware, if you save without text (and uca number in short description/name). Then open the project in ZT, ZT will crash if you mouse over your animal/object. You have to save your project again with your own name filled in, in the description/name. Then it won't crash.
Does that make sense? Sigh.