A multimodal approach to treatment and management of rumination syndrome in a California sea lion (Zalophus californianus) (2025)

Ramos, A. M., McClain, A., Dunham, J. M. et al.

Abstract

The management of chronic rumination syndrome in professionally cared-for animals requires a comprehensive and individualized approach. In this case study, a multimodal approach incorporating pharmacological treatment, feeding modifications, and behavioral management was applied to a California sea lion (Zalophus californianus) with rumination syndrome, megaesophagus, and hypothyroidism. Behavioral observations were collected through video recordings both prior to and post-intervention. Interventions included oral naltrexone and contingent reinforcement post-feed to provide alternative enrichment activities after feeding sessions to reduce rumination syndrome, as well as levothyroxine for hypothyroidism. Additionally, dietary modifications involved offering smaller food portions, spreading meals across longer time periods, and feeding in a more upright position to facilitate esophageal passage. Results showed a reduction in the frequency of rumination syndrome, with no visible regurgitated material observed five months post-intervention. The sea lion demonstrated improved engagement in training sessions, voluntary husbandry tasks, and open-water activities, as well as improved interactions with conspecifics. The combination of pharmacological, dietary, and behavioral strategies reduced rumination behavior and improved the animal’s overall quality of life, reinforcing the value of individualized care strategies and multimodal treatment plans in addressing complex medical and behavioral comorbidities. These findings show the importance of individualized, multimodal care plans in managing complex behavioral and medical conditions, and they contribute to advancing animal-welfare practices across species.