I've been looking for answers for 2 years, but nothing. Not even vets can explain these symptoms and where I live I can't make blood/poop tests, so I'm looking for people who have encountered these symptoms before and have some idea of what causes them. I have a male lovebird of about 6 years of age. About 2 years ago he started to have weird symptoms like vomiting a white foam, regurgitating food, trying to mate every single day with what he can, producing some sort of growling sounds from his abdomen area like people when we're hungry, eating his own poop and my other birds' poop and papers, and finally losing weight (I can feel his front bone area became sharp). I did an AVB test with chest feathers at Avian Biotech UK but it came out negative. I also had a budgerigar who was vomiting frequently and had his crop/proventriculus extremely dilated and you could see millet from his skin (his abdomen was full of liquid and undigested seeds), who died after two surgeries and 4 years later since the symptoms began to show. The budgerigar wasn't tested for anything. Nobody knows what he had. The dilatation started to develop at about the age of 2. I suspect it was PDD but no vet could confirm it. We don't have avian vets here. So, if anyone knows what causes the growling sounds in his abdomen, or has seen similar cases before, please spend some minutes to tell me what the cause is and maybe the treatment used to cure this. My lovebird was recently treated with Linco-Spectin, Duphalyte, and Enroxil (enrofloxacin) and there's no improvement.