On 17 May 1991, a female beluga whale presented clinically with inappetence. Hematology and chemistries were unremarkable. She was kept under observation and nutrition was provided by assisted feeding. On 19 May, endoscopic examination revealed ulcerative lesions in the distal third of the esophagus. The mucosal lining of the first gastric compartment was intact. Approximately a square foot section of gastric mucosa was regurgitated on 22 May and a second smaller section on 24 May. The animal remained alert but anorexic. The first dramatic changes in the hematology and chemistries were not observed until 31 May at which time the hemoglobin started to drop while the white blood cell count and erythrocyte sedimentation rate became elevated. There was also a slight rise in the serum creatine phosphokinase. Prior to these changes, the serum protein had dropped to 4.8 gm/dl on 23 May, returning to 6.4 gm/dl on 31 May. The animal was treated symptomatically for a severe, acute ulcerative esophagitis and gastritis. Endoscopy revealed dramatic healing of both the esophagus and stomach by 27 May. Only three small unhealed areas remained in the cardia region of the stomach on 18 June 1991. The entire esophagus and forestomach were completely healed on 15 August 1991.

Gastric erosions and ulcerations are not uncommon in mammals. It would be considered rare however, for lesions as extensive as those observed in this beluga whale to completely resolve without any observable complications.