I ferment my feed with excellent results. I ferment crumble or pellet organic feed with some scoops of some additions I want them to be eating. I do just 3 days. Any longer and the chickens don't eat it as quick. I always keep the "juice" after I drain my feed , I always have two intches of water on top, for the next batch.
The main thing to remember is that "There are two primary types of fermentation - yeast fermentation and lacto-fermentation. Yeast fermentation produces alcohol, but lacto-fermentation produces lactic acid. Yeast tends to dominate when there are lots of simple sugars (such as in fruit, or adding molasses to barley) and lactic acid bacteria tend to dominate when there are more complex carbohydrates or lower amounts of sugar (such as in cabbage or dairy products)."
The fermentation you are doing for chicken feed is lacto-fermentation, we are converting the carbs in the feed to lactic acid, which produces great probiotic effects, and improves the nutritional intake of the feed. This is how you make kimchi, krout, and pickles. Which no matter how hard you try, can't get you drunk D:
Interestingly some fermentation methods are a mix of both fermentations, like kombucha, great probiotic that does create alcohol in trace ammounts, or if you leave it on the counter long enough and keep giving it sugar, lots of alcohol!