Metabolic profiles of captive Asian elephants (Elephas maximus) in Lao PDR and Thailand

Abstract

This study compared metabolic health biomarkers, lipid profiles, body condition scores (BCS), and adrenocortical function of 78 captive Asian elephants ( Elephas maximus ) managed under contrasting systems in Laos and Thailand. In Laos, elephants are primarily managed in naturalistic forest environments with limited tourist interaction, while many Thai elephants participate in tourism activities like riding and are fed calorie-dense supplemental foods, with restricted access to natural forage. Serum and fecal samples were collected for 1 year to assess serum glucose, insulin, cholesterol, triglycerides, lipoproteins, fecal glucocorticoid metabolites (fGCM), and BCS across seasons, sexes, and management regimens. Thai elephants exhibited significantly higher glucose, insulin, lipid levels, and BCS, reflecting the effects of high-calorie diets and reduced exercise, while Lao elephants displayed healthier metabolic profiles and BCS, attributed to natural foraging and physical activity. In Thai elephants, BCS was positively correlated with insulin, and negatively correlated with the glucose-to-insulin ratio, total cholesterol, HDL, and LDL, suggesting overweight elephants in Thailand are at risk of metabolic derangements. None of those parameters were significantly correlated with BCS in the Laotian population. A surprising finding was higher fGCM in Lao elephants, which could have been related to new social opportunities and pandemic-driven management disruptions at the Elephant Conservation Center. These findings underscore how management practices, particularly diet composition, exercise opportunities, and degree of naturalistic living, can influence the health and welfare of captive elephants and support the adoption of more naturalistic management strategies to improve elephant welfare in captivity.