: 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 are attracted to rotting material, particularly rotting or decaying vegetation or flesh. If garbage is left out in a home, it is not uncommon to find maggots in the garbage within days. They thrive in warm, moist environments, and thus maggot infestations are most common in homes with poor moisture control and high temperatures.