Do old feeds get deleted?

I scrolled down my feeds and wanted to see my first feed to see a comment  someone made. So I can search the name on MDL.  I was surprised to see my first feed not there. I rarely post on feeds, and was wondering if this was a feature on MDL where feeds get deleted after a certain period of time. 

 Ji-N:

Nope, but there is a bug that makes the post not displaying randomly.

Thanks. Glad to know they don't get deleted. ^_^