Hi again Marko:
Check this web site out. It could be the answer you are looking for.
I remember seeing things like this many years ago and thought they would be handy to have around in a multi animal household where food was an issue.
Scroll well down the page to watch the video........tells and shows you how it works.
https://www.amazon.com/Our-Pets-Inte...PQCZZY4SYYYWZC