Absolutely! Not pasteurized, though. Raw unfiltered probiotics goodness :D
That'll kick start the fermentation process, and add in some extra nutrients as well :) Shouldn't need too much; depending on how much feed you're fermenting, a cup would innouculate a 5 gallon bucket with enough to keep...
Just a tip; using RAW Apple cider vinegar will boost the probiotics count by like, a million, lol. ;)
It's a starter enzyme in the "mother" that you want. It'll ferment WAY faster and have more microflora in it :)
Edit* or brewers yeast, that's another good microbe starter :)
Yep, they need calories in winter to help them stay warm :)
As long as the feed isn't moldy, you can sure ferment it; it would increase nutritional value since it seems that the feed has obviously lost most if its nutrients by now. Since it IS questionable what quality the feed us, I would also...