: 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.
Maggots work because they eat dead tissue (debridement) within the wound, which can promote infection. This treatment seems to help reduce the risk of infection after surgery because the larvae are thought to secrete substances that fight infection.