This is for starting fermentation? What about established, back-slopping established batches? And how does cereal grain translate to chicken feed?
"Cereal grain" in question is maize and sorghum. Maize is corn. Sorghum may or may not be found in individual chicken feed recipes, but virtually all chicken feed recipes have grains in them. The principle of fermenting corn is highly relevant ...
Did I miss what the composition of the greul is? In the US, most packaged baby cereal is just rice. (And if they are breastfeeding, how critical is the fermentation? What would happen if they used a breastmilk based ferment? ) Heh.
I'm going to completely ignore the question of breast feeding for brevity ... I'm typing in my iPhone and honestly don't have/will never have kids so that isn't my area of expertise.

Understanding the conversation at this point relies on reading the links ... or we risk me re typing the all and adding a bunch of mistakes and misunderstandings.
But here goes a starter course ...
Two studies ... both that I linked to today for overlapping reasons.
The first study I linked to today was for grain-based pig feed where starter culture was used, the feed was allowed to ferment for 5 days, then it was fed out and "refreshed" with 80% new feed and 20% backslopping for 5 days with measures if the properties of the colonies in the feed. That study showed some control of some undesirables due to the ferment/starter, but a lack of control of yeast cultures ... meaning the starter did not prevent yeast cultures from growing.
The second study I linked to today was for traditional fermented baby food in Nigeria where fermented cereal gruel -- made from soaked, ground, strained and then fermented maize and/or sorghum -- is used for weening babies (and continues to be eaten through life). Health organizations have two primary concerns with the traditional fermented baby food: 1) is it nutritionally adequate to be used as a primary diet for babies; 2) is it hygienic. The question about nutrition is due to the rather poor nutritional value of the base ingredients. The hygiene concern is because with lack of controlled environments and lack of refrigeration, etc., there is lots of death due to diarrhea, particularly with infants. The interest in the traditional fermented food is because it seems a much more practical solution to hunger/poverty than imported baby foods ...
This second study is interesting to me primarily because it quantifies the nutritional boost that is achieved by fermenting grains ... the base ingredients in the rations we are fermenting to feed our chickens. There is a pretty big boost in nutrition when grains are fermented! Though the study suggest the big boost comes from ferments where a specific starter was used (a combination of two specific strains of L.) instead of "natural" ferment. This study was also interesting because it showed a decrease in the undesirables through fermentation ... that relates back to the first study I linked to.
So ... I'm wondering if it is possible to get one's hands on these specific starters. It seems it could be worth it!