If a food without preservatives is being used (or if one with a preservative which has a shorter time frame is being used) then people need to be extra careful about food storage time both at stores and home, please. (We have and have had food with and without.) The fungi which can start can have incredibly serious health consequences. (One interesting piece of history is about a walled city which wound up with it's gates locked and the city turned into a refuge for the insane inhabitants after fungus contaminated bread flour was used. Think that problem was Ergot if memory serves, but not sure.) BTW, some components of toxins produced by some of the fungi as well as those produced by some bacteria which can set in are demonstrated to have carcinogenic properties. The simple fact is that when tackling risk factors there is NO such thing as being completely safe, just in looking at the rates and making your own personal choices, and that's true for all. So, if you avoid preservatives just be extra careful about time-frames and storage conditions of your ferret food, okay? [Posted in FML issue 2613]