Medical and Behavioral Management of Chronic Regurgitation in a Pacific Walrus (Odobenus rosmarus divergens)
Over a 2-year period, an immature female walrus began to routinely regurgitate her food. This behavioral problem ultimately resulted in a weight loss that was leading to a life-threatening situation. Medical causes for regurgitation were ruled out based on the sporadic nature of the problem, physical examination, radiographic evaluation, and normal blood parameters.
A variety of training, feeding, and enrichment techniques were employed in an attempt to extinguish the aberrant behavior. One method the trainers tried initially was a technique that had been used successfully in a similar case at another facility called satiation.1 The trainers attempted to satiate the animal by increasing the amount of food offered each feed. The regurgitation improved initially with each enrichment or dietary change and then worsened in spite of new creative attempts to eliminate the behavior. When these techniques proved unsuccessful and the walrus continued to lose weight, the animal was treated with haloperidol (Haldol, Roxane Laboratories, Inc., Columbus, OH), a tranquilizer used in human medicine in the management of manifestations of psychotic disorders. An oral dose of 20 mg in the morning and 15 mg in the afternoon proved effective in controlling the regurgitation problem in this animal; however, it had several undesirable side effects, most notably involuntary muscle spasms especially in the facial muscles and lips, and occasional spasms in the abdominal muscles. A variation on the first satiation technique was then tried whereby the walrus was separated from the other walruses and fed fish from a tub until she was satiated. This technique was successful and the animal gained substantial weight. Once the regurgitation problem had resolved, the haloperidol was slowly discontinued over a 4-month period. The walrus still regurgitated sporadically but continued to gain weight on the satiation program and is now the same size as the other three walruses with which it was raised.
We thank Dr. Jim McBain, Dr. Michael Walsh, Dr. Tom Reiderson, Bill Winhall and Dana Wynn from the Sea World Adventure Parks for their valuable contributions to this case.
1. Flynn T. Conditions and treatment of an eating disorder in a pacific walrus—an anecdotal report. In: Proceedings from the 15th Annual Conference of the International Marine Animal Trainers Association. 1987:39–46.