So I just had a post asking why bailey had a bad smell on her but area and I learned it was her anal gland. and with my research I learned that they constantly lick their bum trying to releive the itchyness/pain it cause.
Causes of Pet Anal Gland Problems: Loose Stools, Improper Draining Leads to Infection | Suite101.com
I am no expert and changing food could be the cause but figured I would throw my thoughts out there
thanks