Working Dogs Drinking a Nutrient-Enriched Water Maintain Cooler Body Temperature and Improved Pulse Rate Recovery After Exercise

Abstract

Exercise-related physiological changes were evaluated in hydrated, exercise-conditioned working dogs with free access to tap water (TW) with or without a nutrient-enriched water supplement (NW). Physiological samples and measures were collected before and after work-related field tasks in a warm and moderately humid ambient environment. In a cross-over design study, 12 dogs (age range 8–23 months) were evaluated on 3 separate occasions within each period with exercise bouts up to 30 min, on days −4, 3, and 11. Dogs were offered either ad libitum TW or portion-controlled NW daily plus ad libitum TW. Prior to and serially after exercise, pulse rate (PR), core (BTcore) and ear (BTear) temperature were recorded. Urine was collected first thing in the morning, whereas blood samples collected and body weight (BW) recorded pre- and immediately post exercise. Ambient temperature was above 21.7°C (71°F) and relative humidity ranged from 36 to 76%. Activity parameters, AM urine measures, post-exercise percent change of BW, resting PR and resting BTcore did not differ between treatment groups on any exercise day. At the completion of exercise, mean BTcore for all dogs ranged from 104.8 to 105.6°F. Immediate post-exercise BTear was always lower compared to BTcore and means ranged from 103.3 to 104.0°F. The effect of time was highly significant (P < 0.001) for both BT measures with both BTcore and BTear recovering to resting levels by 60 min post exercise. PR and several blood values showed a significant main effect of time. Over the recovery period, dogs in the NW group had lower mean BTear and PR by 0.6°F and 3.4 bpm, respectively. Daily ingestion of a NW in combination with free access to TW can reduce the post-exercise-related BTcore and BTear hyperthermia, and improve pulse rate recovery following exercise in this population of working dogs undergoing 30 min bout of exercise.

Changes in Body Surface Temperature Associated with High-Speed Treadmill Exercise in Beagle Dogs Measured by Infrared Thermography

“…A study based on sport dogs, which measured core body temperature with ingestible sensors and ear temperature with IRT, reported temperature returning to resting levels 60 min after exercise [19]. In our study, however, the surface temperature in all regions was not significantly elevated above pre-exercise levels beyond the cessation of exercise on the treadmill.…”

“…Studies based on a group of baboons indicated that excitement increased the heart rate from 75 ± 4 to 208 ± 14 beats/min and mean arterial pressure from 92 ± 3 to 144 ± 9 mmHg (p < 0.01) [27]. In the literature, it is well documented that any type of positive stress caused by excitement induces an increase in core body temperature, leading to an elevated surface temperature in dogs [13,19]. A study on the emotional state of Beagles concluded that the dogs were excited not only by the expectation of a reward, but also by the realization that they themselves can control access to the reward [26].…”

Expert Perspectives on the Performance of Explosive Detection Canines: Performance Degrading Factors

“…Other factors are unknown beforehand (e.g., novel floor surface), may have an inconsistent effect (e.g., wind speed and direction), and may not result in changes in performance apparent to the handler (e.g., helicopter transport) [25]. Whatever form these factors may take, further exploration is needed to identify the specific impact on performance, develop monitoring tools, and devise mitigations to sustain performance wherever possible [26,27].…”

The Animal Welfare Science of Working Dogs: Current Perspectives on Recent Advances and Future Directions

“…Working dogs have increased nutritional demands due to the nature of their work. Detection and protection dogs often work in adverse environments and are engaged in physical activity that can lead to dehydration (78)(79)(80). Even 15 min of retrieving a ball can lead to fluid loss and detectable dehydration (81).…”