Hi, I noticed today that one of my budgieís vent has become stained green because of feces, and every couple of seconds heíll open his mouth. I originally thought he was adjusting his crop but heís not closing his eyes or stretching his neck, heís also been doing it for a long time. I did switch to a new food the other week but heís only just started showing signs so I donít think itís that. Can some people please give me some ideas of what it could be? Iíve already contacted the regular vet and asked if anyone specialises in birds and Iím waiting for a reply. Apart from the mouth opening and dirty vent, he is acting normally.