What we know about their nutritional need is that they vary between birds, at different stages of growth, times of year, and levels of activity.
My hope is that this method will better provide for those requirements.
And we also know that those differences are generally small. However, the base nutritional needs in certain key nutrients is well above what they can obtain from natural plant sources.
Here's one of the better metastudies, collecting a large number of other's research on amino acids and at times comparing results. Let's poke around table three, for isntance.
Here we compare the recommendations for a number of similar commercial layers.
At first glance, there aren't huge differences there. Hyline Browns and Isa Browns are pretty needy, to support their modern expectations. The classic, -lite and W36 allmuch closer to the old NRCS recommends.
But all of them are looking for roughly 700 mg/b/day of lysine or more, and roughly half as much Met. They are based on feeding about 100g/day of feed, meaning met levels of about .35% and Lys levels of about 0.7% of total intake.
Table 5 looks at daily energy intakes. Generally from about 11.5 to 12.25 MJ/kg.
Now we think abvout ingredients.
Soft wheat averages just .2 Met and .36 Lys. with an MJ/kg around 13.8.
That means a bird trying to meet its daily energy needs with soft wheat reaches its target with less than 100g of wheat (about 90 g, actually) but has met barely half its Met requirement, and less than half its Lys needs.
Triticale? .18, .45, 14.5 Better on Lys (but still not nearly enough), worse on Met, and hits energy needs event sooner.
Sorghum .18, .23, 15.7 Even worse than Triticale
Rye .17, .40, 13.3 (similar to soft wheat, though with far more anti-nutritional factors)
Oats .19, .47, 11.9 - roughly 2/3 of the key amino levels when the energy needs are met.
Corn .2, .3, 15.1 - only sorghum fares worse.
Grass, because of its high moisture content (and thus low nutritional density) underperforms every one of these grains, substantially. That means that just to meat the energy needs, the bird has to eat far more weight of the stuff, and will still be massively sub par on key aminos.
THAT is why I can say a backyard monculture doesn't work, withotu needing to try it.
Nor will any combination of corn, oats, rye, sorghum, tritale, and wheat allow a bird to balance its needs. I can even throw in the near grains, amaranth [.37, .90, now we are getting somewhere... 16.9 oh], flax (seed) [.47, .97. 16.1) and tef [.54, .48, 15.7], the answer remains the same.
In order to have a hope of balancing just two amino acids and daily energy, my birds also need something like cottonseed meal (.66, 1.9, 10.6), soy meal, (.69, 3.0 yes 3!, 10.6), Brewer's Yeast (.73, 3.1, 9.3), Corn Gluten meal (1.6, 1.1, 16.9) Fish meal (2.1, 5, 16) or similar.
Now as it turns out, if you get the crude protein to a minimum level, and the first two amino acids right, you will probably get the next two important aminos right in a grain based diet. So we'll call that good enough. Calcium you can suppliment independently, since there are calcium dense sources containing almost nothing else, that's easy. Now you just need a non-phytate phosphorus source (which you already have if you used the fish meal, porcine blood meal, crab meal, insect protein meal, etc) and a bunch of vitamins to consider (some of which you get easily with the grains, some of which are easier to get with the animal stuff). others are better from the legumes (I have four different clovers growing, for instance).
So yes, with
enough variety always available, it can be done. I've not said otherwise.
Science has shown that. Experience supports the conclusion. But that same science and experience demonstrably concludes that a backyard lawn doesn't suffice. Just as you don't find feral flocks of self sufficent chickens over most of the planet.
Chickens, by the way,
don't regulate individual amino acid intake well.
.
