There are roughly 1 billion head of cattle in the world, depending on the soil and climate you need anywhere from 2-25 acres per head of cattle to 100% grass fe

There are roughly 1 billion head of cattle in the world, depending on the soil and climate you need anywhere from 2-25 acres per head of cattle to 100% grass feed them (in areas where this is done, obviously 25 acres of desert isn't going to feed a cow). Even if we assume an average of 3 acres per head, you're looking at 3 billion acres of land just to keep beef going (never mind the 785 million pigs and 33 billion chickens). If you entirely pasture feed, you're going to get lower slaughter weights too as their weight at slaughter averages about 1,200 pounds compared with about 1,350 pounds for feedlot animals, you'd end up needing something like 30% more cattle to get the same amount of meat https://awellfedworld.org/grazing/ https://awellfedworld.org/grazing/