It is free of fly larvae. Cool game meat is stored out of the sun at all times. Air is allowed to freely circulate around it. The microorganisms that spoil meat multiply more rapidly in warm temperatures. Dry game meat is not allowed to become wet after initial drying.
Moisture is another key element for the growth of microorganisms.
If meat can be kept dry, their growth will be retarded. In rare circumstances you will be able to remove an animal from the field whole. In most cases' field butchering is the only means of transportation and you need to be prepared. Strong fly-proof game bags are a necessity for the pieces of the animal you have butchered. Meat will usually keep for a week or more in the field if kept cool and dry.