3.5 once for 22 pounds of feed
The fermentation of the feed is made by a group of Bacteria that do lactic fermentaion, which is different than the Ethanol fermentation in wine that is made by yeasts. This bacteria, especially the lactobacilus genus, is part of the microbiom that are the trilion bacteria and other, thst live in and on the chicken (or human!) And help preventing disease by producing vitamins, and preventing establishment of Pathogens. In fact fermented feed is acting like daily dose of probiotics .