YV 3.6o

He cuts off eleven portions; ten are the vital airs of the beast, the body is the eleventh, he cuts off as much as is the size of the beast [3]. First he makes a portion of the heart, then of the tongue, then of the breast: what he conceives with the heart, that he says with the tongue; what he says with the tongue, that he utters from the breast. That is the order in the case of the beast. If he cuts off thus and then cuts from the rest at will, still the cutting off from that animal has been made in order. In the middle he makes a portion of the intestines, for breath is in the middle; he makes a portion of the upper part [4], for breath is in the upper part; whether he does one, or the other, there is variation in both cases. A Brahman on birth is born with a threefold debt, of pupilship to the Rsis, of sacrifice to the gods, of offspring to the Pitrs. He is freed from his debt who has a son, is a sacrificer, and who has lived as a pupil: this (debt) he performs (ávadayate) by these cuttings off', and that is why the cuttings-off (avadána) have their name. The gods and the Asuras were in conflict. The gods said to Agni, 'With thee as our hero let us overcome the Asuras' [5]. He said, 'Let me choose a boon; let me have a choice part of the beast.' He chose that choice part (of the beast), the shoulder from the fore part, the intestines from the middle, the hip from the hind part. Then the gods prospered, the Asuras were defeated; in that he makes portions of three members it is for the overcoming of his foe; he prospers himself, his foe is defeated. He cuts off transversely; therefore cattle move forward their limbs transversely, for support. He covers the dipping-spoons with fat; cattle are distinguished by fat; verily he bestows on cattle their distinguishing mark. He covers (them) after putting (the fat) on the soup; the soup is the sap of cattle; verily he bestows sap upon cattle.