And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind; and it was so.
And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind. (1) God did not permit Adam and his wife to kill a creature and to eat its flesh. Only every green herb shall they all eat together. (2)
You are permitted to use the animals and employ them for work, have dominion over them in order to utilize their services for your subsistence, but must not hold their life cheap nor slaughter them for food. Your natural diet is vegetarian.
Tsa'ar ba'alei chayim - the Torah mandate, not to cause "pain to any living creature."