Genesis 1:29

It shall be for meat— It is evident from this grant of food to man, in the present verse, and from that to the brute animals in the next, that the use of flesh in the beginning was allowed to neither: and, consequently, that the now carnivorous animals then fed upon grass, &c. as the tame ones amongst us do at present. The ancients mention this as one characteristic of the golden age:

"Not so the golden age, who fed on fruit, Nor durst with bloody meals their hands pollute."