From an essay by Scott Corales, first published in Paranoia Magazine and reprinted at Inexplicata.  (h/t David Metcalfe):

At sunrise, when it was no longer a sacrilege to approach the patches of desert where the gods had made their presence felt, the shamans would check to see if their offering had been accepted, and it always was: the carcass was now completely drained of blood, with the tell-tale puncture mark visible somewhere on the body–neck, hindquarters, stomach–indicating that the gods’ thirst had been slaked. It was now time for the priests and the tribe to share the meal with the gods by eating the sacrifice’s flesh, whose remains would ultimately be buried under a cairn as reminder of the bond between mortals and their deities.