Assessment of Adrenocortical Activity and Behavior of the Collared Anteater (Tamandua tetradactyla) in Response to Food‐Based Environmental Enrichment

摘要

One of the current standard approaches to the study of animal welfare is measuring hypothalamic-pituitary-adrenal activity, frequently in association with behavioral assessment. We studied the effects of food‐based environmental enrichment on adrenocortical activity and behavior in zoo‐housed collared anteaters (Tamandua tetradactyla; n?5). We successfully validated measurements of fecal cortisol metabolites (FCMs) using an 11‐oxoetiocholanolone enzyme immunoassay by stimulating (ACTH injection) and suppressing (dexamethasone administration) adrenocortical activity. Three months later, we subjected animals to an ABA‐type experiment (three 6‐week periods): pre‐enrichment (routine diet: A), enrichment (modified diet: B), and post‐enrichment (routine diet: A) periods. We assessed adrenocortical activity by collecting individual feces three times a week (total number of samples: 228), and evaluated behavior by performing 3 days of behavioral observations per period (with a total of 3,600 behavioral data points for the individuals studied). Statistical analysis revealed changes in FCM concentrations (μg/g) over the periods (3.04±0.68, 2.98±0.66, and 4.04±0.90, respectively). Additionally, it showed that the number of FCM peaks was highly reduced during enrichment; meanwhile active natural behaviors were significantly increased. We consider that these changes in response to food‐based environmental enrichment improved the welfare of individual zoo‐housed collared anteaters. This research might contribute to in situ and ex situ studies on the physiology and behavior of this endemic South American species. Zoo Biol. 32:632-640, 2013.