Use of salivary cortisol to evaluate the influence of rides in dromedary camels

- Validated EIA for salivary cortisol in camels via ACTH challenge.
- Found salivary cortisol is effective for measuring short term responses to stressors.
- Ruminant saliva decreases after refrigeration and multiple freeze thaw cycles.
- Performing rides is not a stressful experience on camels.
- Evidence suggests rides are a form of environmental enrichment.

Animals in captivity and in the wild face numerous challenges, including the risk of enduring acute or chronic stress. In captivity, facilities attempt to alleviate the risk of chronic stress by providing environmental enrichment, shown to minimize behavioral disorders and stress in several species. One potential form of enrichment in zoos is training animals to provide rides for guests, however, the effect of this activity on the welfare of individual animals has never been examined. We validated the use of saliva for assessing stress in dromedary camels (Camelus dromedarius), an animal commonly used for rides. We then measured variation in salivary cortisol in four male camels while providing rides of differing frequency for guests at the Toronto Zoo. The camels were sampled during the ride season (June to September) using four treatments: (1) in their pasture, (2) at the ride area when not performing rides, (3) while providing a low number of rides (n = 50/day) and (4) while providing a high number of rides (n = 150/day). Furthermore, samples were taken before and after the ride season for comparison. There was a significant difference between the post-ride season treatment and the three treatments involving guest presence during the ride season (ride area, low rides, high rides). In general, cortisol concentrations were lower during the ride season and higher during the non-ride season. Based on the metrics we used, performing rides is not a stressful experience for these dromedary camels and suggests that rides may be a form of enrichment.