Diarrhea associated with small-intestinal cryptosporidiosis in a budgerigar and in a cockatiel.

Small-intestinal cryptosporidiosis has not been described in budgerigars or cockatiels. Organisms of the genus Cryptosporidium were found during histologic examination of segments of small intestine from a budgerigar with chronic weight loss and from a cockatiel that died acutely. Parasitism was accompanied by non-purulent inflammation (lymphocytes and plasma cells predominated). Bacterial and viral pathogens were not isolated. The death of the budgerigar was attributed to malassimilation interpreted to have been caused by Cryptosporidium. The cause of death in the cockatiel was inhalation pneumonia. Because the index of suspicion for cryptosporidiosis was low, samples for isolation of Cryptosporidium were not collected. In the future, cryptosporidiosis should be included as a differential diagnosis for weight loss and death in pet birds, and isolation and speciation of Cryptosporidium sp. should be attempted and reported.