If you're lucky enough to pack elk out with livestock--horses or mules, one would typically use canvas panniers. It's important to cut and load the carcass so the bone ends face out and don't poke the pack animal. With a pack animal you don't need to save weight by deboning in the field which is time consuming and risks contamination. Keeping the meat (and hide) on the bone and using game bags helps keep the meat clean until it gets into refrigeration and on to the butcher table.

A bone saw is used in the field to cut the carcass into carry sized pieces. Eight sections plus the head works well for efficient loading. After removing the legs, I cut the across the ribs about 6" from the backbone in order to keep the backstraps intact. Then the spine is cut in half through the vertebra between the 4th and 5th rib bones. I do this at the time of field dressing whether packing out on my frame backpack or bringing in the pack animals.