Fermented feed for chickens

[Shadrach]

The crop acts as a natural fermentation chamber,

In the studies I've read there seems to be some doubt that digestive enzymes from the birds mouth survive in the crop. I'm not saying you're wrong, just worth mentioning.

 

[CabritaChicks]

In the studies I've read there seems to be some doubt that digestive enzymes from the birds mouth survive in the crop. I'm not saying you're wrong, just worth mentioning.

Im not wrong. Never talked about the mouth. Let me know next time you have to do 5-10 crop cultures a day for the last 10 years. Chickens already handle this process on their own. The crop naturally performs mild fermentation, thanks to resident lactic-acid bacteria, so there really isn’t a biological requirement to ferment feed beforehand. In many cases it simply adds another variable to manage, and if conditions aren’t ideal it can actually create more problems than benefits, especially when feed sits wet in heat or humidity.

The other piece people sometimes overlook is how the avian digestive system is designed to control nutrient absorption. Birds have a fairly precise flow through the crop, proventriculus, gizzard, and small intestine that regulates how nutrients are released and absorbed. Certain nutrients—particularly fat-soluble vitamins like A, D, E, and K—are absorbed through lipid digestion pathways and stored in the body, so they are normally delivered in controlled amounts through formulated feeds. Water-soluble nutrients move through the system differently and excess is typically excreted. This staged digestive process is one reason balanced feeds are formulated the way they are (and yes- they may move faster): nutrients are meant to be available at specific points in the digestive tract rather than pre-processed unpredictably by uncontrolled fermentation handed to them on a silver platter that they were born to accept as 'food'.

So while fermentation can soften grains and may work for some keepers, chickens already perform the necessary microbial breakdown themselves, and their digestive system is designed to regulate nutrient absorption without needing that extra step.

 

[Rillowen]

Let me start with chickens have been doing just fine in the digestion department for thousands of years without humans fermenting their food.

Somewhere in your post you write that human and chicken digestive systems are similar; I'm just not seeing this. Even if one ignores those odd tacked on bits like the crop and the ceca glands, there is one major difference that stands out like a bag of stones...and that's because that's what it is. Granted, it's very strong bag. Give it time it will crush a whole corn and fire it out as a paste. Some pictures of what goes in at one end of the gizzard and what comes out at the other are instructive, or even a look next time one does a necropsy or butchers a bird to eat.


Then there is this.
It was found in studies (a few linked to in my article) that commercial feed which even in pelleted form traveled through a chickens digestive system faster than any other offered feeds. One suggested reason for this was the gizzard was doing a pass through rather than a grinding process. Now that's efficient, but it isn't very good for the chicken. Their gizzard muscles get weak, the digestive enzymes don't get enough time before the gizzard to do their chemical breakdown. It's a point I've mentioned in the past to people who have taken in Ex Battery hens, feed them commercial feed on arrival and gradually introduce whole grains, seeds etc.
I could draw a parallel between the current nutrition drive in the UK health system for humans, where it seems we are not eating nearly enough fiber in our diets because we're eating a lot of processed slop. It gives rise to numerous gut health related problems apparently.
Same for the chickens. They need strong gizzards and left to grind down dry whole grains and seeds that's what they develop.

As the commercial feed manufacturers have discovered, if you can get a bird to eat more they'll grow faster. Similar for egg production, there are ratios of nutrients that effect the number of eggs a hen will lay,

So, efficiency; is this a good thing or a bad thing for the chicken when it comes to their digestion. Fine I suppose if the bird is never going to eat anything else, but if stuff like this goes on for long enough generation to generation it seems possible that we will have breeds of chickens that can no longer digest natural food.

Also often over looked in some of the more enthusiastic advocates of fermented feed is the chemical changes from fermentation do increase some nutrients but they decrease others. How does one work out what nutrients from one particular grain or seed one wants to boost or reduce for a chicken? Seems a bit like throwing darts blindfold.

If keepers want to ferment wholefoods for the birds I think it's fine. I've done it myself and may do it again. What I would suggest is as wide a variety of components as one can manage. It's a bit of a learning process and the keepers I know who feed wholefoods, dry or fermented, find themselves adjusting the components over time; one can even make seasonal adjustments.

"Chickens have been doing just fine in the digestion department for for thousands of years without humans fermentation their feed" Ummmm, you know what they eat in the wild right? whether they were largly eating free range with scraps on a farm (as they have been doing for thousands of years) or living in the jungle large portions of their food would be fermented. Wild fermented, and by default often half rotten, OR the fermented leftovers from the farm, since every culture in the world relied heavily on the preservation powers of fermentation all the way until the invention of the freezer and industrial canning. If we are talking about what they eat in the wild you have definitely lost the battle here.

It helps with efficiency in terms of available nutrient extraction, doesnt actually lessen the grinding need by much more than you would get from soaked feed, or simply not dried wild fodder. I would like to clarify that i do not think simply fermenting commercial feed is reall the best course. You are correct that many have crop weaknesses due to a "lack of fiber". Commercial feeds often have many shortcommimgs and problems and thisnis one of them. Fermenting does nothing for or against this, except that the probiotics you are fostering are the same ones that transform that fiber into the enzymes and nutrients needed, and the entire reason for soluble fiber needs in the first place. (Look it up if you don't believe me, "tributyrin" is a good example).

As for increasing the amount the chicken eats, that actually has more to do with how much of the calories, protien, fats, and nutrients they get than food consumed. In this way fermented food helps, since half the nutrients they couldnt extract before and just went right back out the other end can now actually be digested. For the point about bacteria using up some of the nutrient, yes that woild be a concern, if we weren't fostering the exact bacteria they and we were designed to use for digestion. Its really kind of "too convenient", but its real! Further evidence of Devine planning if you ask me. Either way the nutrients lost are ones not needed or synthesized in other ways, most of what is lost is actually just straight calories. The nutrients not added or subtracted change form to a more absorbable form. (almost like we and they were meant to work together... ..)

The "bag of rocks" actually performs pretty similar tasks to our teeth and saliva. Incidentally their are completely necessary probiotics for pre-digestion and immune protection in both. Some, even most, of those necessary probiotics are the ones we foster during fermentation.

I whole heartedly agree with whole foods and variety! I think more of the chickens diet should be this anyway. However I do think the fermentation process helps reverse some of the damage caused by commercial feed, such as changing some of the toxic but shelf stable versions of the vitamins into better forms.

 

[Perris]

Im not wrong. Never talked about the mouth. Let me know next time you have to do 5-10 crop cultures a day for the last 10 years. Chickens already handle this process on their own. The crop naturally performs mild fermentation, thanks to resident lactic-acid bacteria, so there really isn’t a biological requirement to ferment feed beforehand. In many cases it simply adds another variable to manage, and if conditions aren’t ideal it can actually create more problems than benefits, especially when feed sits wet in heat or humidity.

The other piece people sometimes overlook is how the avian digestive system is designed to control nutrient absorption. Birds have a fairly precise flow through the crop, proventriculus, gizzard, and small intestine that regulates how nutrients are released and absorbed. Certain nutrients—particularly fat-soluble vitamins like A, D, E, and K—are absorbed through lipid digestion pathways and stored in the body, so they are normally delivered in controlled amounts through formulated feeds. Water-soluble nutrients move through the system differently and excess is typically excreted. This staged digestive process is one reason balanced feeds are formulated the way they are (and yes- they may move faster): nutrients are meant to be available at specific points in the digestive tract rather than pre-processed unpredictably by uncontrolled fermentation handed to them on a silver platter that they were born to accept as 'food'.

So while fermentation can soften grains and may work for some keepers, chickens already perform the necessary microbial breakdown themselves, and their digestive system is designed to regulate nutrient absorption without needing that extra step.

This is very interesting; thank you.

I miss any mention of the caeca. Is that because scientific studies of chicken digestion have typically worked with caecetomized birds?

My understanding is that quite a lot more microbial activity goes on in the caeca, and that the chickens are then able to absorb more nutrients as bacterial/viral/fungal metabolites. I believe that fermentation of grains etc. feeds various microbes in the gut beyond the crop; it is not just about the lactobacilli.

 

[Altairsky]

I ferment a lot of stuff for myself (kombucha, tempeh, kefir, gingerbug, tepache, etc.).
It is pointless to ferment commercial feed. Commercial feed is nutritionally balanced, since nothing can be created from nothing, you're just going to transform a balanced feed to something with a different nutritional profile that you don't know if it's still balanced or not. Fermentation increases certain nutrients, but consume others.
Nothing is created, nothing is destroyed, everything is transformed.

Commercial feed is also ultra processed and a dead substance. You want to ferment live things, things that have life, like sauercraut, soy, raw milk, or whole seeds for chickens for example.
Fermenting whole seeds helps removing a few anti nutrients, and the acidic environment with Lactobacillus help the chicken gut.

If you don't want to feed your chickens whole fermented seeds, just give them their regular commercial feed and moisten it with white, full fat, unsweetened yoghurt and a spoon of apple cider vinegar once or twice a week. They'll get the exact same benefits of fermented feed without the risk of serving them a bowl of feed that has turned into a smelly rotten slime - with botulism risk.

 

[Altairsky]

So @Rillowen please explain how fish, for example, survive in water if it is an anaerobic environment.

if you put a fish in a jar, and make the jar air tight, the fish will suffocate and die from lack of oxygen. So in this specific case, the water is anaerobic.
This is why you can get botulism from eating canned stuff that has not been preserved in the correct way (enough acid/salt/sugar).

If the jar is open the fish won't die. So the water in an open jar is aerobic.

 

[Perris]

if you put a fish in a jar, and make the jar air tight, the fish will suffocate and die from lack of oxygen. So in this specific case, the water is anaerobic.
This is why you can get botulism from eating canned stuff that has not been preserved in the correct way (enough acid/salt/sugar).

If the jar is open the fish won't die. So the water in an open jar is aerobic.

thanks. I understand that. It's Rillowen's understanding I was probing.

 

[CabritaChicks]

This is very interesting; thank you.

I miss any mention of the caeca. Is that because scientific studies of chicken digestion have typically worked with caecetomized birds?

My understanding is that quite a lot more microbial activity goes on in the caeca, and that the chickens are then able to absorb more nutrients as bacterial/viral/fungal metabolites. I believe that fermentation of grains etc. feeds various microbes in the gut beyond the crop; it is not just about the lactobacilli.

That’s a great point — and you’re absolutely right, the caeca are busy little fermentation hubs.

I didn’t focus on them earlier because, in terms of fermented feed, most of what people are trying to influence happens upstream. By the time feed reaches the caeca, the bird has already absorbed the bulk of the “good stuff.” The caeca step in to ferment what’s left — mostly fiber and leftovers — producing short-chain fatty acids that support gut health and provide a bit of extra energy.

A couple key points:

• The crop and caeca are not the same game — crop = early, simple fermentation (Lactobacillus), caeca = deeper, anaerobic cleanup crew.
• Most critical nutrients are absorbed before the caeca, so they’re not the main driver of nutrition.
• The microbiome is already well-adapted — adding fermented feed doesn’t “upgrade” it, it just changes the inputs, sometimes in messy ways.

And yes — some research used caecectomized birds, but even in intact birds, the consensus holds: properly formulated feed is designed to be digested before the caeca even get involved.

Chickens are not hindgut/butt gut fermenters in the way sheep or even rabbits are. They’re still primarily designed to extract nutrition upstream:

• Proteins → digested and absorbed in the small intestine
• Fats → absorbed early via bile-mediated pathways
• Most vitamins and minerals → absorbed before the caeca

By the time feed reaches the caeca, what’s left is essentially the “leftovers bin” — useful, but not the main meal.

So when people say “the caeca are the most critical,” they’re usually talking about fiber fermentation specifically, not overall nutrition. That distinction gets lost.

So yes, the caeca mater — a lot. But they don’t need our help fermenting things ahead of time. Chickens already have a full, layered system dialed in. Sometimes we step in thinking we’re helping… and just end up complicating something that was working perfectly fine on its own, and apologies- Im just really geeky over avian nutrition. lol.

It’s not to say you can’t ferment feed — if your chickens enjoy it, eat well, stay hydrated, and you don’t mind the extra step, then it can absolutely be part of your routine. The issue, in my opinion, is the growing idea that it’s somehow required, which isn’t supported by poultry nutrition science.

I’ll also admit I have some questions about how quickly chicken feed “ferments” in home settings. In my own experience, feed can turn into a bubbly, active mix within 24–48 hours, while other true fermentation processes take much longer to stabilize. My theory commercial feeds already carry naturally occurring microbes, and once you add water and warmth, you’re essentially accelerating microbial growth — not necessarily creating a controlled or consistent fermentation. Research shows rapid microbial proliferation under warm, moist conditions, but that doesn’t always mean it’s stable or beneficial. And yes, I have made my own yogurt, kefir, kimchi, alcohol

So yes — ferment if it works for you. I just don’t view it as necessary, and in some cases it becomes more of an uncontrolled microbial experiment than a consistent nutritional strategy. Okay… I was bored and just wrote a novel. Sorry.