ThainaYu said:
The actual reason I think about this is to resurrect... horse and cow farming around the world. To have green energy and preserve friendly animal relationship
Then focus on the "efficiency" of the animal feed lol, or maybe more specifically on the efficiency of the animal to turn feed into food
How does an efficiently mobile farm animal improve the profitability of farming? Even in wealthy N.America green farming or "Organic" is not profitable (comparatively, often literally), this is food, not politics.
My hungry stomach doesn't give two hoots about how "dirty" it was to get food on my plate; my stomach only cares if and how much food there is, and for me and most people (hopefully) that's $$ related, not good for the environment related.
A long shot of an analogy, but drug addicts don't typically care where the drugs come from or if they were produced in an environmental friendly manner, just that there is an abundance

.
"Green" food production is more of a "culture" thing then an economics thing, because abundant food production requires and abundance of "fuel" of all types. In other words until the fuel "issue" is resolved "dirty" will always be much cheaper than "clean", nearly by definition of clean/dirty in this context (a comparative).
...I wonder what the "carbon footprint" difference is between an individual of "healthy" weight and one of obese weight, maybe the "carbon footprint" of food production per capita of your "homeland" is already comparatively "Green".
just a very general spewing of my opinion.