ARTICLE | doi:10.20944/preprints202003.0132.v1
Online: 8 March 2020 (04:40:36 CET)
Body temperature responses were recorded during phases of work (waiting to work in close proximity to search site, active work in a search site, and post-work recovery crated in vehicle) in human remains detection dogs during search training. State or federally certified human remains detection dogs (n = 8) completed eight iterations of searching, rotating through six different types of search environments to detect numerous scent sources including partial and complete, buried, hidden, or fully visible human remains. Internal temperature (Tgi) of the body was measured continuously using an ingestible thermistor in the gastrointestinal tract. Mean total phase times were: waiting to work: 9.17 minutes (± 2.27); active work: 8:58 minutes (± 2:49); and post work recovery: 24:04 minutes (± 10.59). Tgi was impacted by phase of work (P < 0.001) with a small increase during active work, with mean peak temperature 39.4 °C (± 0.34 ºC) during that period. Tgi continued to increase for a mean of 7:37 (± 6:04) minutes into the post-work recovery phase in the handler’s vehicle with a mean peak Tgi of 39.66 °C (± 0.41 ºC). No significant increase in temperature was measured during the waiting to work phase, suggesting anticipation of work did not appear to contribute to overall body temperature increase during the waiting to work recovery cycle. Continued increase of gastrointestinal body temperature several minutes after cessation of exercise indicates that risk of heat injury does not immediately stop when the dog stops exercising, although none of the dogs in this study reached clinically concerning body temperatures or displayed any behavioral signs suggestive of pending heat injury. More work is needed to better understand the impact of vehicle crating on post-work recovery temperatures in dogs.