Megabacteria have recently been shown to be novel anamorphic ascomycetous yeasts and not bacteria.The name Macrorhabdus ornithogaster has been given to the organism and the disease is referred to as “avian gastric yeast infectionThe organism causes a progressively debilitating, gastrointestinal disease typical of malnutrition characterized by emaciation, prostration, anorexia, cachexia, and death (2). Mortality can be as high as 90%