: an act of showing someone how something is used or done : demonstration. 1  I saw a demo on how to use the computer program. 2  The salesman gave us a demo of the vacuum cleaner, and it seemed to work very well. [+] more examples [-] hide examples [+] Example sentences [-] Hide examples 3
If however, you are talking about some maggots in a bowl of wet food (either canned food or dry food which got wet or which you deliberately added fluid to) it is a different matter. Maggots come from flies eggs and they take some set period of time to hatch from the eggs.
I know of two practical routes. First is by mouth, through direct ingestion of maggot-laden foods. In this case, the maggots do not live for very long before the digestive acids kill them and strip them of nutrients for the human's use. Second, an open wound visited by flies, if not cleaned, will grow maggots hatched from the flies' eggs, laid in the wound.