Non-Invasive Assessment of the Seasonal Stress Response to Veterinary Procedures and Transportation of Zoo-Housed Lesser Anteater (Tamandua tetradactyla)

SIMPLE SUMMARY: Wild mammals under human care are routinely exposed to management procedures that could be stressful and affect their welfare. Besides, wild animals in captivity are frequently housed under natural climatic conditions, which could also be a year-round challenge that affects how they cope with human intervention. Therefore, stress responses to seasons and management procedures of zoo-housed lesser anteaters (Tamandua tetradactyla) were non-invasively monitored. Behavioural and physiological stress responses differed between seasons. Then, lesser anteaters were studied during winter and summer by exposing them to a routine veterinary check and transportation. Behaviour before and after the procedures was video-recorded and analysed for possible alterations of activity. Faecal glucocorticoid metabolites were measured to evaluate adrenocortical activity. Both procedures altered only behavioural activities, and the response was stronger in summer than winter. We conclude that routine procedures may only slightly compromise the welfare of zoo-housed lesser anteaters, affecting them less in winter than in summer. ABSTRACT: Management procedures affect behavioural and physiological stress responses of wild mammals under human care. According to the Reactive Scope Model, normal values are presumed to exist within predictive and reactive ranges. First, stress parameters of zoo-housed adult Tamandua tetradactyla were evaluated in winter and summer (29 days each), determining the level of behaviour and/or physiological parameters needed to respond to predictable environmental changes. Secondly, the effects of veterinary procedures and transportation were studied in both seasons. Non-invasive methods were applied, assessing behaviour through videos and adrenocortical activity by faecal glucocorticoid metabolites (FGMs). Lesser anteaters exhibited seasonality (summer > winter) in some behavioural parameters, such as nocturnal activities, as well as in the activity cycle (e.g., acrophase) and FGMs. A veterinary check elicited an increase in total activity (TA), natural behaviours and repetitive locomotion and affected the activity cycle, particularly in summer. Transport produced changes in TA, nocturnal and natural activity and some variables of the activity cycle, mostly during summer. Although the effects of routine management procedures were different from each other and presumably stressful, they elicited changes only at the behavioural level, which was greater during summer. The differences observed according to non-invasive methodologies highlight the importance of a multidisciplinary approach in this context and suggest that it is unlikely that individual welfare was affected.