You could try the attahed script. Upload to Catalogs -> Extra Files -> Monitor Programs. Then create a new Monitor of type "External program monitor" under Catalogs -> Monitors.
By default the monitor will use tcp, so you need to add an argument of "proto" to the monitor and set it to "udp", you will also need to provide a "send" and "expect" argument which contain the string to send and the response to expect. The "expect" string can be PCRE regex if needed. If the port you are monitoring is different to the port on which the service runs, then you will also need to set that in "monport".
The params you can add are: send. expect, monport, and proto