An outbreak of severe Macrorhabdus ornithogaster infection in common canaries (Serinus canarius domesticus), Molecular and pathological assay

Infection by Macrorhabdus ornithogaster (MO) formerly called Megabacteriosis has been diagnosed as the cause of depression, wasting, regurgitation, fluffed feathers, lethargy, and soft watery bulky feces and also the cause of mortality in a flock of breeding canaries over a long period of time (3 months) in Mashhad, Iran. Large numbers of Macrorhabdus ornithogaster were detected in wetmount fecal preparations of the feces and direct smears from mucosal scrapings of proventrilculus of one bird under light microscopy. The diagnosis was confirmed by demonstrating a chronic proventriculitis histologically which was associated with MO organisms along with molecular tests.