EN
An adult female budgerigar (Melopsittacus undulatus) was presented with severe dyspnea and microscopically diagnosed with advanced Trichomonas infection. The bird was bought two weeks before presentation and kept with two males in the same room. Because of the negative prognosis the budgerigar was euthanized. Further investigation revealed massive yellow caseous masses in the oropharynx which caused upper larynx blockage, liver massive necrosis and small intestine haemorrhagic inflammation. Psittacine circovirus infection was confirmed with PCR method, while Clostridium perfringens, Enterococcus sp., Enterobacter sp. were cultured from intestine samples. These mixed protozoal and bacterial infections were most probably the effect of immunosuppression caused by Psittacine Beak and Feather Disease.