Meeting the complex nutritional needs of hippopotamuses in zoological settings.
Hippo dietary welfare in captivity requires careful balance between providing the extensive low-quality grass-based diet the species evolved for and managing obesity in animals with naturally high intake drives confined in environments where the energy expenditure of wild hippos cannot be replicated. Zoo hippos provided abundant high-quality hay and supplementary vegetables often become obese, with associated joint, cardiovascular, and reproductive welfare consequences. Dietary management programs based on controlled hay quantities and limited supplementary feeding, while challenging to enforce with species that show strong appetitive behavior, produce better long-term welfare outcomes than unrestricted provision.