Chronic Vomiting in Budgie, please help
I know this is a bit long, but I really don't know who else to ask at this point
What could be causing my budgie's chronic vomiting?
For almost a year now, my budgie Simon has been vomiting up whole seeds mixed with mucous and it's recently been getting worse. The mucous is clear, and when he vomits he usually stretches out his neck once, then moves his beak a bit as a small amount of mucous gathers around the tip of his beak, then he shakes his head from side to side and flings it. I usually find it dried around his head feathers. I have not noticed a pattern to when he vomits (for example, after eating). He still has a decent appetite and his droppings seem normal, but sometimes he vomits multiple times a day.
I've taken him at least three times to see exotic and/or avian veterinarians and all three times they couldn't find the problem. I took him to the vet just a few weeks ago because he was not only vomiting up seeds and mucous, but making a sort of kicking motion near his vent with his foot. The vet examined him, looking in his mouth, around his crop area, and his vent, but didn't find anything. His vent was clean. She recommended a diet of Lafaber Nutri-berries because they won't eat pellets, so that's what I have been giving them for the past few weeks. Also lettuce and other vegetables.
Although tonight I have them in separate cages because Simon was having a fit of vomiting, he is usually housed with another parakeet that has never exhibited these symptoms and is a high-energy, healthy bird. I do separate them when Simon starts vomiting and clean out their water & food dishes, and any object the vomit touched just in case it is contagious (although it really doesn't seem to be).
I'm starting to think he might have some sort of tumor since the symptoms seem to be getting a bit worse.