Files of the Zoo/Exotic Pathology Service for 1984 to 2002 contain over 20,000 accessions of which over 15,000 are birds. Of these accessions 6.95% have been diagnosed with neoplastic disease. Birds from eight families are represented, including Anseriformes, Ciconiiformes, Columbiformes, Falconiformes, Galliformes, Passeriformes, Psittaciformes, and Struthioniformes.
The ten most common species with a diagnosis of neoplasia are Psittaciformes (9) or Passeriformes (1). The bird with the most neoplasia diagnoses is the cockatiel, which is the fourth most commonly submitted species. Although the literature indicates that tumors are most often found in budgerigars there has been concern that this simply reflects the fact that more budgerigars are seen. In our data, budgerigars are the seventh most common species, but the second most prevalent with tumor diagnoses. Our single most common species submitted is the cockatoo (all types), but it is the fifth most common with a diagnosis of neoplasia.
The organ system with the most tumors diagnosed is the skin and subcutis. The gastrointestinal tract and liver are the next most common systems/organs with tumors. The skin and subcutis is also the most commonly involved organ in five of the ten birds most frequently diagnosed with tumors. For three of the most commonly submitted birds (Amazon parrot, macaw, and conure) the cloaca is the single most commonly involved organ, with the liver and proventriculus respectively being the most common in the other two most frequently submitted species.
The most commonly diagnosed tumor, regardless of site of origin, is the papilloma. Carcinomas (all sites) and fibrosarcomas are the next most common tumor types diagnosed.