How to make Fermented feed

This article is just the writer's opinion and doesn't give any scientific explanation on how fermenting processed feed improves an already balanced diet, especially if probiotics are already listed as ingredient in the feed bag. The concept that fermenting feed makes you save money is misinformation, because inflating dry feed with water and gas doesn't add calories to it.
Fermentation is great on whole seeds (reduction of anti nutrients, improved bioavailability of locked nutrients, whole seeds never rot) , fermentation is pointless or even harmful on processed feed (no anti nutrients in processed feed, no locked nutrients to unlock, all vitamins already available, often probiotics are already added plus as the writer stated it might rot instead of fermenting).
Processed (crumbles and pellets) feed already has all the nutrients a chicken need. The nutritional values are written in the bag. Fermentation changes the nutritional value of an already balanced feed to something we don't know. It is highly probable, from studies on other ferment like Kefir and kombucha, that the probiotic bacteria will consume certain nutrients from the bag to grow. Therefore, the author needs to prove, with before and after lab analysis, that processed feed, at least doesn't lose the nutrients stated in the feed label.
For a probiotic effect on chickens, it is much safer and more beneficial to add yogurt or Kefir to their crumble feed and make a mash, so you're sure that you're adding beneficial bacteria and you don't give these bacteria enough time to consume the vitamins in the feed, so the feed stay balanced as stated in the bag label, plus you have all the benefits of yogurt probiotics and extra protein.