This is a common question, but cows and chickens eat lots of plants too.
"All the fertilizer, tractor fumes, transportation, ground tilling, you name it, that go into producing a pound of grain are literally multiplied by 4.5 to produce a pound of chicken breasts, or by 20 to produce a pound of ground beef."
"All the fertilizer, tractor fumes, transportation, ground tilling, you name it, that go into producing a pound of grain are literally multiplied by 4.5 to produce a pound of chicken breasts, or by 20 to produce a pound of ground beef."
https://stanfordmag.org/contents/can-vegetarianism-save-the-...